Pub Date : 2024-09-05DOI: 10.1186/s41479-024-00137-9
Johannes Rukyaa, Martha F Mushi, Vitus Silago, Prisca Damiano, Katherine Keenan, Wilber Sabiiti, Matthew T G Holden, Jeremiah Seni, Stephen E Mshana
Background: Bacterial pneumonia is among the leading causes of morbidity and mortality worldwide. The extensive misuse and overuse of antibiotics observed during the Corona Virus Disease 2019 (COVID-19) pandemic may have changed the patterns of pathogens causing bacterial pneumonia and their antibiotic susceptibility profiles. This study was designed to establish the prevalence of culture-confirmed bacterial pneumonia and describe their antimicrobial susceptibility profile in adult patients who presented with signs and symptoms of lower respiratory tract infections (LRTIs) during the COVID-19 pandemic.
Methodology: This hospital-based cross-sectional study was conducted from July 2021 to July 2022 at a zonal referral hospital and two district hospitals in Mwanza, Tanzania. Demographic and clinical data were collected using a standardized questionnaire. Sputum samples were processed by conventional culture followed by the identification of isolates and antibiotic susceptibility testing. Descriptive data analysis was performed using STATA version 15.0.
Results: A total of 286 patients with a median age of 40 (IQR 29-60) years were enrolled in the study. More than half of the patients enrolled were females (52.4%, n = 150). The overall prevalence of bacterial pneumonia was 34.3% (n = 98). The majority of the bacterial pathogens isolated were Gram-negative bacteria (GNB) (61.2%, 60/98), with a predominance of Klebsiella spp., 38.8% (38/98), followed by Streptococcus pyogenes (21.4%, 21/98). Multi drug resistant (MDR) bacteria were detected in 72/98 (73.5%) of the isolates. The proportions of GNB-resistant strains were 60.0% (36/60) for ciprofloxacin, 60% (36/60) for amoxicillin, 60% (36/60) for amoxicillin, 68.3% (41/60) for trimethoprim-sulfamethoxazole and 58.3% (35/60) for ceftriaxone.
Conclusion: One-third of the patients with signs and symptoms of LRTIs had laboratory-confirmed bacterial pneumonia with a predominance of Gram negative MDR bacteria. This calls for continuous antimicrobial resistance (AMR) surveillance and antimicrobial stewardship programs in the study setting and other settings in developing countries as important strategies for tackling AMR.
{"title":"Etiology and antimicrobial susceptibility patterns of bacteria causing pneumonia among adult patients with signs and symptoms of lower respiratory tract infections during the COVID-19 pandemic in Mwanza, Tanzania: a cross-sectional study.","authors":"Johannes Rukyaa, Martha F Mushi, Vitus Silago, Prisca Damiano, Katherine Keenan, Wilber Sabiiti, Matthew T G Holden, Jeremiah Seni, Stephen E Mshana","doi":"10.1186/s41479-024-00137-9","DOIUrl":"10.1186/s41479-024-00137-9","url":null,"abstract":"<p><strong>Background: </strong>Bacterial pneumonia is among the leading causes of morbidity and mortality worldwide. The extensive misuse and overuse of antibiotics observed during the Corona Virus Disease 2019 (COVID-19) pandemic may have changed the patterns of pathogens causing bacterial pneumonia and their antibiotic susceptibility profiles. This study was designed to establish the prevalence of culture-confirmed bacterial pneumonia and describe their antimicrobial susceptibility profile in adult patients who presented with signs and symptoms of lower respiratory tract infections (LRTIs) during the COVID-19 pandemic.</p><p><strong>Methodology: </strong>This hospital-based cross-sectional study was conducted from July 2021 to July 2022 at a zonal referral hospital and two district hospitals in Mwanza, Tanzania. Demographic and clinical data were collected using a standardized questionnaire. Sputum samples were processed by conventional culture followed by the identification of isolates and antibiotic susceptibility testing. Descriptive data analysis was performed using STATA version 15.0.</p><p><strong>Results: </strong>A total of 286 patients with a median age of 40 (IQR 29-60) years were enrolled in the study. More than half of the patients enrolled were females (52.4%, n = 150). The overall prevalence of bacterial pneumonia was 34.3% (n = 98). The majority of the bacterial pathogens isolated were Gram-negative bacteria (GNB) (61.2%, 60/98), with a predominance of Klebsiella spp., 38.8% (38/98), followed by Streptococcus pyogenes (21.4%, 21/98). Multi drug resistant (MDR) bacteria were detected in 72/98 (73.5%) of the isolates. The proportions of GNB-resistant strains were 60.0% (36/60) for ciprofloxacin, 60% (36/60) for amoxicillin, 60% (36/60) for amoxicillin, 68.3% (41/60) for trimethoprim-sulfamethoxazole and 58.3% (35/60) for ceftriaxone.</p><p><strong>Conclusion: </strong>One-third of the patients with signs and symptoms of LRTIs had laboratory-confirmed bacterial pneumonia with a predominance of Gram negative MDR bacteria. This calls for continuous antimicrobial resistance (AMR) surveillance and antimicrobial stewardship programs in the study setting and other settings in developing countries as important strategies for tackling AMR.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"16"},"PeriodicalIF":8.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11375869/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142134157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-25DOI: 10.1186/s41479-024-00136-w
Linda Yamba Yamba, Karin Hansen, Lisa Wasserstrom, Yu-Ching Su, Jonas Ahl, Kristian Riesbeck
Background: Haemophilus influenzae community-acquired pneumonia (CAP) is common, and it is equally common to Streptococcus pneumoniae in some settings. The purpose of this study was to provide additional data on patients affected by H. influenzae CAP and their outcomes.
Methods: Streptococcus pneumoniae-caused CAP (111 cases) was compared to CAP with H. influenzae (53 cases). Patients were adults (≥ 18 years) from the prospective study "Etiology of community acquired pneumonia in Sweden" (ECAPS), which was established during the years 2016-2018.
Results: Cases with H. influenzae CAP were significantly older compared to S. pneumoniae CAP (median 77 vs 70 years, p = 0.037) albeit similar comorbidities. Haemophilus influenzae was generally absent in the bloodstream compared to S. pneumoniae (18% vs 2%, p = 0.01) but clinical presentations were comparable. Only a minority of patients, 34% with H. influenzae and 41% with S. pneumoniae CAP had underlying lung disease.
Conclusion: In the light of childhood immunization campaigns against S. pneumoniae and the increasing numbers of pneumococcal vaccinations among the elderly, coupled with an aging population, the incidence of CAP caused by H. influenzae may increase. Further research is needed to understand the impact of H. influenzae CAP and to a development of a vaccine against this emerging microbe.
背景:流感嗜血杆菌社区获得性肺炎(CAP)很常见,在某些情况下与肺炎链球菌同样常见。本研究旨在提供更多有关流感嗜血杆菌社区获得性肺炎患者及其治疗效果的数据:方法:将肺炎链球菌引起的 CAP(111 例)与流感嗜血杆菌引起的 CAP(53 例)进行比较。患者均为成人(≥ 18 岁),来自 2016-2018 年期间开展的前瞻性研究 "瑞典社区获得性肺炎病因学"(ECAPS):结果:尽管合并症相似,但流感嗜血杆菌 CAP 病例的年龄明显高于肺炎链球菌 CAP 病例(中位数 77 岁 vs 70 岁,p = 0.037)。与肺炎双球菌相比,流感嗜血杆菌一般不出现在血流中(18% 对 2%,p = 0.01),但临床表现相似。只有34%的流感嗜血杆菌和41%的肺炎双球菌CAP患者有潜在的肺部疾病:结论:鉴于肺炎双球菌的儿童免疫接种活动和老年人接种肺炎球菌疫苗的人数不断增加,再加上人口老龄化,由流感嗜血杆菌引起的 CAP 发病率可能会增加。要了解流感嗜血杆菌 CAP 的影响,并开发出针对这种新出现微生物的疫苗,还需要进一步的研究。
{"title":"The importance of Haemophilus influenzae in community-acquired pneumonia: an emerging pathogen in the elderly regardless of comorbidities compared to Streptococcus pneumoniae.","authors":"Linda Yamba Yamba, Karin Hansen, Lisa Wasserstrom, Yu-Ching Su, Jonas Ahl, Kristian Riesbeck","doi":"10.1186/s41479-024-00136-w","DOIUrl":"10.1186/s41479-024-00136-w","url":null,"abstract":"<p><strong>Background: </strong>Haemophilus influenzae community-acquired pneumonia (CAP) is common, and it is equally common to Streptococcus pneumoniae in some settings. The purpose of this study was to provide additional data on patients affected by H. influenzae CAP and their outcomes.</p><p><strong>Methods: </strong>Streptococcus pneumoniae-caused CAP (111 cases) was compared to CAP with H. influenzae (53 cases). Patients were adults (≥ 18 years) from the prospective study \"Etiology of community acquired pneumonia in Sweden\" (ECAPS), which was established during the years 2016-2018.</p><p><strong>Results: </strong>Cases with H. influenzae CAP were significantly older compared to S. pneumoniae CAP (median 77 vs 70 years, p = 0.037) albeit similar comorbidities. Haemophilus influenzae was generally absent in the bloodstream compared to S. pneumoniae (18% vs 2%, p = 0.01) but clinical presentations were comparable. Only a minority of patients, 34% with H. influenzae and 41% with S. pneumoniae CAP had underlying lung disease.</p><p><strong>Conclusion: </strong>In the light of childhood immunization campaigns against S. pneumoniae and the increasing numbers of pneumococcal vaccinations among the elderly, coupled with an aging population, the incidence of CAP caused by H. influenzae may increase. Further research is needed to understand the impact of H. influenzae CAP and to a development of a vaccine against this emerging microbe.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"15"},"PeriodicalIF":8.5,"publicationDate":"2024-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11344911/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142056822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Introduction: Ethiopia is one of those countries with higher burden of community acquired pneumonia among its people, under five children are the members of society that are highly affected by pneumonia particularly Severe Community Acquired Pneumonia. However, there are limited studies on time to recovery and its predictors in under-five children and most of them are retrospective which fails to address important variables that affect the time to recovery. Therefore, the aim of this study was to estimate the median time to recovery and its predictors among under five children admitted to South Wollo zone public hospitals, North East Ethiopia.
Methods: An institution-based prospective cohort study was conducted from March 10 to May 10, 2021, with 270 study subjects. A systematic random sampling technique was used. Data was collected by interview and chart review. The data were entered and analyzed using Epi Data version 3.1 and STATA version 14.0, respectively. Kaplan-Meier and Cox regression models were used to test the time and predictors of recovery from severe community-acquired pneumonia.
Results: The overall incidence of recovery rate (95% confidence interval) from Severe Community-Acquired Pneumonia was 20.45(17.84-23.46) per 100 person days observation with median (IQR) time to recovery of [3, 5] days. The predictors of time to recovery from Severe Community-Acquired Pneumonia were having comorbidities on admission [AHR = 0.49 (95%CI: 0.32,0.75)], reaching hospitals after 5 days of onset of symptoms [AHR = 0.35 (95%CI: 0.20,0.60)], having Middle Upper Arm Circumference < = 12.5 cm [AHR = 0.21 (95%CI: 0.12,0.37)], the presence of smoker in the house [AHR = 0.21 (95%CI: 0.10,0.42)] and being not fully immunized for age [AHR = 0.35 (95%CI: 0.24,0.53)].
Conclusion and recommendations: Generally the recovery time of children with Severe Community Acquired Pneumonia in the study area was within the recommended national standards. Due attention should be given to children with the identified predictors while treating them.
{"title":"Time to recovery from severe community-acquired pneumonia and its predictors among 6 to 59 months of age children admitted to South Wollo zone public hospitals, North East Ethiopia: a prospective follow-up study.","authors":"Mekonnen Teferi, Elsabeth Addisu, Shambel Wodajo, Amare Muche, Abel Endawekie, Bezawit Adane, Tilahun Dessie, Natnael Kebede","doi":"10.1186/s41479-024-00135-x","DOIUrl":"10.1186/s41479-024-00135-x","url":null,"abstract":"<p><strong>Introduction: </strong>Ethiopia is one of those countries with higher burden of community acquired pneumonia among its people, under five children are the members of society that are highly affected by pneumonia particularly Severe Community Acquired Pneumonia. However, there are limited studies on time to recovery and its predictors in under-five children and most of them are retrospective which fails to address important variables that affect the time to recovery. Therefore, the aim of this study was to estimate the median time to recovery and its predictors among under five children admitted to South Wollo zone public hospitals, North East Ethiopia.</p><p><strong>Methods: </strong>An institution-based prospective cohort study was conducted from March 10 to May 10, 2021, with 270 study subjects. A systematic random sampling technique was used. Data was collected by interview and chart review. The data were entered and analyzed using Epi Data version 3.1 and STATA version 14.0, respectively. Kaplan-Meier and Cox regression models were used to test the time and predictors of recovery from severe community-acquired pneumonia.</p><p><strong>Results: </strong>The overall incidence of recovery rate (95% confidence interval) from Severe Community-Acquired Pneumonia was 20.45(17.84-23.46) per 100 person days observation with median (IQR) time to recovery of [3, 5] days. The predictors of time to recovery from Severe Community-Acquired Pneumonia were having comorbidities on admission [AHR = 0.49 (95%CI: 0.32,0.75)], reaching hospitals after 5 days of onset of symptoms [AHR = 0.35 (95%CI: 0.20,0.60)], having Middle Upper Arm Circumference < = 12.5 cm [AHR = 0.21 (95%CI: 0.12,0.37)], the presence of smoker in the house [AHR = 0.21 (95%CI: 0.10,0.42)] and being not fully immunized for age [AHR = 0.35 (95%CI: 0.24,0.53)].</p><p><strong>Conclusion and recommendations: </strong>Generally the recovery time of children with Severe Community Acquired Pneumonia in the study area was within the recommended national standards. Due attention should be given to children with the identified predictors while treating them.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"14"},"PeriodicalIF":8.5,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11299310/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141890391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-25DOI: 10.1186/s41479-024-00134-y
Mercy Wendy Wanyana, Richard Migisha, Patrick King, Abraham Kibaba Muhesi, Benon Kwesiga, Daniel Kadobera, Lilian Bulage, Alex Riolexus Ario
Background: Pneumonia is one of the leading causes of infant mortality globally, particularly in sub-Saharan Africa. In Uganda, pneumonia was the fourth leading cause of death in children <5 years in 2018. Analysis of 2013-2022 data for children <5 years from the District Health Information System indicated a high incidence of severe pneumonia in Kasese District, Uganda. We investigated to identify factors associated with severe pneumonia among children <5 years in Kasese District to inform prevention and control strategies.
Methods: We conducted a 1:1 hospital-based case-control study among children aged 2-59 months presenting with pneumonia at five high-volume facilities in Kasese District from January to April 2023. A case was defined as pneumonia with ≥1 of the following danger signs: low oxygen saturation, central cyanosis, severe respiratory distress, feeding difficulties, altered consciousness, and convulsions. Controls were outpatient children aged 2-59 months with a diagnosis of non-severe pneumonia. We reviewed medical records at facilities and used an interviewer-administered questionnaire with caregivers to obtain information on socio-demographic and clinical characteristics. Logistic regression was used to identify factors associated with severe pneumonia.
Results: We enrolled 199 cases and 174 controls. The odds of severe pneumonia were higher among children with diarrhoea only (adjusted odds ratio [aOR] = 2.9, 95%CI: 1.7-4.9), or malaria and diarrhoea (aOR = 3.4, 95%CI: 2.0-5.9), than those without a co-existing illness at the time of pneumonia diagnosis. Not being exclusively breastfed for ≥ 6 months (aOR = 2.0, 95%CI: 1.1-3.3) and exposure to indoor air pollution from cooking combustion sources (aOR = 2.9, 95%CI: 1.8-4.7) increased odds of severe pneumonia.
Conclusion: The findings highlight the significance of comorbidities, lack of exclusive breastfeeding, and exposure to indoor air pollution in the development of severe pneumonia. Promoting exclusive breastfeeding for ≥ 6 months and advocating for the use of clean energy sources, could mitigate morbidity attributable to severe pneumonia in the region.
{"title":"Factors associated with severe pneumonia among children <5 years, Kasese District, Uganda: a case-control study, January-April 2023.","authors":"Mercy Wendy Wanyana, Richard Migisha, Patrick King, Abraham Kibaba Muhesi, Benon Kwesiga, Daniel Kadobera, Lilian Bulage, Alex Riolexus Ario","doi":"10.1186/s41479-024-00134-y","DOIUrl":"10.1186/s41479-024-00134-y","url":null,"abstract":"<p><strong>Background: </strong>Pneumonia is one of the leading causes of infant mortality globally, particularly in sub-Saharan Africa. In Uganda, pneumonia was the fourth leading cause of death in children <5 years in 2018. Analysis of 2013-2022 data for children <5 years from the District Health Information System indicated a high incidence of severe pneumonia in Kasese District, Uganda. We investigated to identify factors associated with severe pneumonia among children <5 years in Kasese District to inform prevention and control strategies.</p><p><strong>Methods: </strong>We conducted a 1:1 hospital-based case-control study among children aged 2-59 months presenting with pneumonia at five high-volume facilities in Kasese District from January to April 2023. A case was defined as pneumonia with ≥1 of the following danger signs: low oxygen saturation, central cyanosis, severe respiratory distress, feeding difficulties, altered consciousness, and convulsions. Controls were outpatient children aged 2-59 months with a diagnosis of non-severe pneumonia. We reviewed medical records at facilities and used an interviewer-administered questionnaire with caregivers to obtain information on socio-demographic and clinical characteristics. Logistic regression was used to identify factors associated with severe pneumonia.</p><p><strong>Results: </strong>We enrolled 199 cases and 174 controls. The odds of severe pneumonia were higher among children with diarrhoea only (adjusted odds ratio [aOR] = 2.9, 95%CI: 1.7-4.9), or malaria and diarrhoea (aOR = 3.4, 95%CI: 2.0-5.9), than those without a co-existing illness at the time of pneumonia diagnosis. Not being exclusively breastfed for ≥ 6 months (aOR = 2.0, 95%CI: 1.1-3.3) and exposure to indoor air pollution from cooking combustion sources (aOR = 2.9, 95%CI: 1.8-4.7) increased odds of severe pneumonia.</p><p><strong>Conclusion: </strong>The findings highlight the significance of comorbidities, lack of exclusive breastfeeding, and exposure to indoor air pollution in the development of severe pneumonia. Promoting exclusive breastfeeding for ≥ 6 months and advocating for the use of clean energy sources, could mitigate morbidity attributable to severe pneumonia in the region.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"13"},"PeriodicalIF":8.5,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270805/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141761513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-05DOI: 10.1186/s41479-024-00133-z
Josef Yayan, Karl-Josef Franke, Melanie Berger, Wolfram Windisch, Kurt Rasche
Tuberculosis remains a significant global health challenge. Tuberculosis affects millions of individuals worldwide. Early detection of tuberculosis plays a relevant role in the management of treatment of tuberculosis. This systematic review will analyze the findings of several published studies on the topic of the early detection of tuberculosis. This systematic review highlights their methodologies and limitations as well as their contributions to our understanding of this pressing issue. Early detection of tuberculosis can be achieved through tuberculosis screening for contacts. Comprehensive health education for household contacts can be used as early detection. The in-house deep learning models can be used in the X-ray used for automatic detection of tuberculosis. Interferon gamma release assay, routine passive and active case detection, portable X-ray and nucleic acid amplification testing, and highly sensitive enzyme-linked immunosorbent assay tests play critical roles in improving tuberculosis detection.
结核病仍然是全球健康面临的重大挑战。结核病影响着全球数百万人。结核病的早期发现在结核病的治疗管理中发挥着重要作用。本系统综述将分析已发表的几项关于结核病早期检测主题的研究结果。本系统综述将重点介绍这些研究的方法和局限性,以及它们对我们了解这一紧迫问题所做的贡献。结核病的早期发现可以通过对接触者进行结核病筛查来实现。针对家庭接触者的全面健康教育可作为早期检测手段。内部深度学习模型可用于自动检测结核病的 X 射线。伽马干扰素释放检测、常规被动和主动病例检测、便携式 X 射线和核酸扩增检测以及高灵敏度酶联免疫吸附检测在改进结核病检测方面发挥着至关重要的作用。
{"title":"Early detection of tuberculosis: a systematic review.","authors":"Josef Yayan, Karl-Josef Franke, Melanie Berger, Wolfram Windisch, Kurt Rasche","doi":"10.1186/s41479-024-00133-z","DOIUrl":"10.1186/s41479-024-00133-z","url":null,"abstract":"<p><p>Tuberculosis remains a significant global health challenge. Tuberculosis affects millions of individuals worldwide. Early detection of tuberculosis plays a relevant role in the management of treatment of tuberculosis. This systematic review will analyze the findings of several published studies on the topic of the early detection of tuberculosis. This systematic review highlights their methodologies and limitations as well as their contributions to our understanding of this pressing issue. Early detection of tuberculosis can be achieved through tuberculosis screening for contacts. Comprehensive health education for household contacts can be used as early detection. The in-house deep learning models can be used in the X-ray used for automatic detection of tuberculosis. Interferon gamma release assay, routine passive and active case detection, portable X-ray and nucleic acid amplification testing, and highly sensitive enzyme-linked immunosorbent assay tests play critical roles in improving tuberculosis detection.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"11"},"PeriodicalIF":8.5,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11225244/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141535647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.1186/s41479-024-00132-0
Fernando García-García, Dae-Jin Lee, Mónica Nieves-Ermecheo, Olaia Bronte, Pedro Pablo España, José María Quintana, Rosario Menéndez, Antoni Torres, Luis Alberto Ruiz Iturriaga, Isabel Urrutia
<p><strong>Background: </strong>There exists consistent empirical evidence in the literature pointing out ample heterogeneity in terms of the clinical evolution of patients with COVID-19. The identification of specific phenotypes underlying in the population might contribute towards a better understanding and characterization of the different courses of the disease. The aim of this study was to identify distinct clinical phenotypes among hospitalized patients with SARS-CoV-2 pneumonia using machine learning clustering, and to study their association with subsequent clinical outcomes as severity and mortality.</p><p><strong>Methods: </strong>Multicentric observational, prospective, longitudinal, cohort study conducted in four hospitals in Spain. We included adult patients admitted for in-hospital stay due to SARS-CoV-2 pneumonia. We collected a broad spectrum of variables to describe exhaustively each case: patient demographics, comorbidities, symptoms, physiological status, baseline examinations (blood analytics, arterial gas test), etc. For the development and internal validation of the clustering/phenotype models, the dataset was split into training and test sets (50% each). We proposed a sequence of machine learning stages: feature scaling, missing data imputation, reduction of data dimensionality via Kernel Principal Component Analysis (KPCA), and clustering with the k-means algorithm. The optimal cluster model parameters -including k, the number of phenotypes- were chosen automatically, by maximizing the average Silhouette score across the training set.</p><p><strong>Results: </strong>We enrolled 1548 patients, each of them characterized by 92 clinical attributes (d=109 features after variable encoding). Our clustering algorithm identified k=3 distinct phenotypes and 18 strongly informative variables: Phenotype A (788 cases [50.9% prevalence] - age <math><mo>∼</mo></math> 57, Charlson comorbidity <math><mo>∼</mo></math> 1, pneumonia CURB-65 score <math><mo>∼</mo></math> 0 to 1, respiratory rate at admission <math><mo>∼</mo></math> 18 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 21%, C-reactive protein CRP <math><mo>∼</mo></math> 49.5 mg/dL [median within cluster]); phenotype B (620 cases [40.0%] - age <math><mo>∼</mo></math> 75, Charlson <math><mo>∼</mo></math> 5, CURB-65 <math><mo>∼</mo></math> 1 to 2, respiration <math><mo>∼</mo></math> 20 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 21%, CRP <math><mo>∼</mo></math> 101.5 mg/dL); and phenotype C (140 cases [9.0%] - age <math><mo>∼</mo></math> 71, Charlson <math><mo>∼</mo></math> 4, CURB-65 <math><mo>∼</mo></math> 0 to 2, respiration <math><mo>∼</mo></math> 30 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 38%, CRP <math><mo>∼</mo></math> 152.3 mg/dL). Hypothesis testing provided solid statistical evidence supporting an interaction between phenotype and each clinical outcome: severity and mortality. By computing their corresponding odds ratios, a clear t
{"title":"Obtaining patient phenotypes in SARS-CoV-2 pneumonia, and their association with clinical severity and mortality.","authors":"Fernando García-García, Dae-Jin Lee, Mónica Nieves-Ermecheo, Olaia Bronte, Pedro Pablo España, José María Quintana, Rosario Menéndez, Antoni Torres, Luis Alberto Ruiz Iturriaga, Isabel Urrutia","doi":"10.1186/s41479-024-00132-0","DOIUrl":"10.1186/s41479-024-00132-0","url":null,"abstract":"<p><strong>Background: </strong>There exists consistent empirical evidence in the literature pointing out ample heterogeneity in terms of the clinical evolution of patients with COVID-19. The identification of specific phenotypes underlying in the population might contribute towards a better understanding and characterization of the different courses of the disease. The aim of this study was to identify distinct clinical phenotypes among hospitalized patients with SARS-CoV-2 pneumonia using machine learning clustering, and to study their association with subsequent clinical outcomes as severity and mortality.</p><p><strong>Methods: </strong>Multicentric observational, prospective, longitudinal, cohort study conducted in four hospitals in Spain. We included adult patients admitted for in-hospital stay due to SARS-CoV-2 pneumonia. We collected a broad spectrum of variables to describe exhaustively each case: patient demographics, comorbidities, symptoms, physiological status, baseline examinations (blood analytics, arterial gas test), etc. For the development and internal validation of the clustering/phenotype models, the dataset was split into training and test sets (50% each). We proposed a sequence of machine learning stages: feature scaling, missing data imputation, reduction of data dimensionality via Kernel Principal Component Analysis (KPCA), and clustering with the k-means algorithm. The optimal cluster model parameters -including k, the number of phenotypes- were chosen automatically, by maximizing the average Silhouette score across the training set.</p><p><strong>Results: </strong>We enrolled 1548 patients, each of them characterized by 92 clinical attributes (d=109 features after variable encoding). Our clustering algorithm identified k=3 distinct phenotypes and 18 strongly informative variables: Phenotype A (788 cases [50.9% prevalence] - age <math><mo>∼</mo></math> 57, Charlson comorbidity <math><mo>∼</mo></math> 1, pneumonia CURB-65 score <math><mo>∼</mo></math> 0 to 1, respiratory rate at admission <math><mo>∼</mo></math> 18 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 21%, C-reactive protein CRP <math><mo>∼</mo></math> 49.5 mg/dL [median within cluster]); phenotype B (620 cases [40.0%] - age <math><mo>∼</mo></math> 75, Charlson <math><mo>∼</mo></math> 5, CURB-65 <math><mo>∼</mo></math> 1 to 2, respiration <math><mo>∼</mo></math> 20 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 21%, CRP <math><mo>∼</mo></math> 101.5 mg/dL); and phenotype C (140 cases [9.0%] - age <math><mo>∼</mo></math> 71, Charlson <math><mo>∼</mo></math> 4, CURB-65 <math><mo>∼</mo></math> 0 to 2, respiration <math><mo>∼</mo></math> 30 min<sup>-1</sup>, FiO<sub>2</sub> <math><mo>∼</mo></math> 38%, CRP <math><mo>∼</mo></math> 152.3 mg/dL). Hypothesis testing provided solid statistical evidence supporting an interaction between phenotype and each clinical outcome: severity and mortality. By computing their corresponding odds ratios, a clear t","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"12"},"PeriodicalIF":8.5,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637184/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141447271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: The Covid-19 pandemic has caused immense pressure on Intensive Care Units (ICU). In patients with severe ARDS due to Covid-19, respiratory mechanics are important for determining the severity of lung damage. Lung auscultation could not be used during the pandemic despite its merit. The main objective of this study was to investigate associations between lung auscultatory sound features and lung mechanical properties, length of stay (LOS) and survival, in adults with severe Covid-19 ARDS.
Methods: Consecutive patients admitted to a large ICU between 2020 and 2021 (n = 173) were included. Digital stethoscopes obtained auscultatory sounds and stored them in an on-line database for replay and further processing using advanced AI techniques. Correlation and regression analysis explored relationships between digital auscultation findings and lung mechanics or the ICU outcome. The resulting annotated lung sounds database is also publicly available as supplementary material.
Results: The presence of squawks was associated with the ICU LOS, outcome and 90-day mortality. Other features (age, SOFA score & oxygenation index upon admission, minimum crackle entropy) had significant impact on outcome. Additional features affecting the 90-d survival were age and mean crackle entropy. Multivariate logistic regression showed that survival was affected by age, baseline SOFA, baseline oxygenation index and minimum crackle entropy.
Conclusions: Respiratory mechanics were associated with various adventitious sounds, whereas the lung sound analytics and the presence of certain adventitious sounds correlated with the ICU outcome and the 90-d survival. Spectral features of crackles sounds can serve as prognostic factors for survival, highlighting the importance of digital auscultation.
{"title":"Back to the future: the novel art of digital auscultation applied in a prospective observational study of critically ill Covid-19 patients.","authors":"Evangelos Kaimakamis, Serafeim Kotoulas, Myrto Tzimou, Christos Karachristos, Chrysavgi Giannaki, Vassileios Kilintzis, Leandros Stefanopoulos, Evangelos Chatzis, Nikolaos Beredimas, Bruno Rocha, Diogo Pessoa, Rui Pedro Paiva, Nicos Maglaveras, Militsa Bitzani","doi":"10.1186/s41479-024-00131-1","DOIUrl":"10.1186/s41479-024-00131-1","url":null,"abstract":"<p><strong>Background: </strong>The Covid-19 pandemic has caused immense pressure on Intensive Care Units (ICU). In patients with severe ARDS due to Covid-19, respiratory mechanics are important for determining the severity of lung damage. Lung auscultation could not be used during the pandemic despite its merit. The main objective of this study was to investigate associations between lung auscultatory sound features and lung mechanical properties, length of stay (LOS) and survival, in adults with severe Covid-19 ARDS.</p><p><strong>Methods: </strong>Consecutive patients admitted to a large ICU between 2020 and 2021 (n = 173) were included. Digital stethoscopes obtained auscultatory sounds and stored them in an on-line database for replay and further processing using advanced AI techniques. Correlation and regression analysis explored relationships between digital auscultation findings and lung mechanics or the ICU outcome. The resulting annotated lung sounds database is also publicly available as supplementary material.</p><p><strong>Results: </strong>The presence of squawks was associated with the ICU LOS, outcome and 90-day mortality. Other features (age, SOFA score & oxygenation index upon admission, minimum crackle entropy) had significant impact on outcome. Additional features affecting the 90-d survival were age and mean crackle entropy. Multivariate logistic regression showed that survival was affected by age, baseline SOFA, baseline oxygenation index and minimum crackle entropy.</p><p><strong>Conclusions: </strong>Respiratory mechanics were associated with various adventitious sounds, whereas the lung sound analytics and the presence of certain adventitious sounds correlated with the ICU outcome and the 90-d survival. Spectral features of crackles sounds can serve as prognostic factors for survival, highlighting the importance of digital auscultation.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"9"},"PeriodicalIF":6.8,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11151547/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rationale: The prevalence, clinical characteristics, and outcomes of invasive pulmonary aspergillosis in patients with severe community-acquired pneumonia (CAP) in intensive care units remain underestimated because of the lack of a disease-recognition scheme and the inadequacy of diagnostic tests.
Objectives: To identify the prevalence, risk factors, and outcomes of severe CAP complicated with invasive pulmonary aspergillosis (IPA) in intensive care units (ICUs).
Methods: We conducted a retrospective cohort study including recruited 311 ICU-hospitalized patients with severe CAP without influenza or with influenza. Bronchoalveolar lavage fluid (BALF) samples were from all patients and subjected to mycological testing. Patients were categorized as having proven or probable Aspergillus infection using a modified form of the AspICU algorithm comprising clinical, radiological, and mycological criteria.
Measurements and main results: Of the 252 patients with severe CAP and 59 influenza patients evaluated, 24 met the diagnostic criteria for proven or probable Aspergillus infection in the CAP group and 9 patients in the influenza group, giving estimated prevalence values of 9.5% and 15.3%, respectively. COPD and the use of inhaled corticosteroids were independent risk factors for IPA. IPA in patients with severe CAP was significantly associated with the duration of mechanical support, the length of ICU stay, and the 28-day mortality.
Conclusions: An aggressive diagnostic approach for IPA patients with severe CAP and not only influenza or COVID-19 should be pursued. Further randomized controlled trials need to evaluate the timing, safety, and efficacy of antifungal therapy in reducing IPA incidence and improving clinical outcomes.
理由:由于缺乏疾病识别方案以及诊断测试的不足,重症监护病房重症社区获得性肺炎(CAP)患者中侵袭性肺曲霉菌病的发病率、临床特征和预后仍被低估:目的:确定重症监护病房(ICU)中并发侵袭性肺曲霉菌病(IPA)的重症CAP的发病率、风险因素和预后:我们进行了一项回顾性队列研究,共招募了 311 名重症监护病房住院的重症 CAP 患者,这些患者既没有患流感,也没有患流感。对所有患者的支气管肺泡灌洗液(BALF)样本进行了真菌学检测。采用改良版的 AspICU 算法(包括临床、放射学和霉菌学标准),将患者分为已证实或可能感染曲霉菌:在接受评估的 252 名重症 CAP 患者和 59 名流感患者中,CAP 组有 24 人符合证实或可能感染曲霉菌的诊断标准,流感组有 9 人,估计感染率分别为 9.5% 和 15.3%。慢性阻塞性肺病和吸入皮质类固醇是导致 IPA 的独立风险因素。重症CAP患者的IPA与机械支持的持续时间、重症监护室的住院时间和28天的死亡率有显著相关性:结论:对于患有重症 CAP 的 IPA 患者,应采取积极的诊断方法,而不仅仅是流感或 COVID-19。需要进一步开展随机对照试验,评估抗真菌治疗在降低 IPA 发病率和改善临床预后方面的时机、安全性和有效性。
{"title":"Invasive pulmonary aspergillosis among patients with severe community-acquired pneumonia and influenza in ICUs: a retrospective cohort study.","authors":"Wei-Chun Lee, Che-Chia Chang, Meng-Chin Ho, Chieh-Mo Lin, Shaw-Woei Leu, Chin-Kuo Lin, Yu-Hung Fang, Shu-Yi Huang, Yu-Ching Lin, Min-Chun Chuang, Tsung-Ming Yang, Ming-Szu Hung, Yen-Li Chou, Ying-Huang Tsai, Meng-Jer Hsieh","doi":"10.1186/s41479-024-00129-9","DOIUrl":"10.1186/s41479-024-00129-9","url":null,"abstract":"<p><strong>Rationale: </strong>The prevalence, clinical characteristics, and outcomes of invasive pulmonary aspergillosis in patients with severe community-acquired pneumonia (CAP) in intensive care units remain underestimated because of the lack of a disease-recognition scheme and the inadequacy of diagnostic tests.</p><p><strong>Objectives: </strong>To identify the prevalence, risk factors, and outcomes of severe CAP complicated with invasive pulmonary aspergillosis (IPA) in intensive care units (ICUs).</p><p><strong>Methods: </strong>We conducted a retrospective cohort study including recruited 311 ICU-hospitalized patients with severe CAP without influenza or with influenza. Bronchoalveolar lavage fluid (BALF) samples were from all patients and subjected to mycological testing. Patients were categorized as having proven or probable Aspergillus infection using a modified form of the AspICU algorithm comprising clinical, radiological, and mycological criteria.</p><p><strong>Measurements and main results: </strong>Of the 252 patients with severe CAP and 59 influenza patients evaluated, 24 met the diagnostic criteria for proven or probable Aspergillus infection in the CAP group and 9 patients in the influenza group, giving estimated prevalence values of 9.5% and 15.3%, respectively. COPD and the use of inhaled corticosteroids were independent risk factors for IPA. IPA in patients with severe CAP was significantly associated with the duration of mechanical support, the length of ICU stay, and the 28-day mortality.</p><p><strong>Conclusions: </strong>An aggressive diagnostic approach for IPA patients with severe CAP and not only influenza or COVID-19 should be pursued. Further randomized controlled trials need to evaluate the timing, safety, and efficacy of antifungal therapy in reducing IPA incidence and improving clinical outcomes.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"10"},"PeriodicalIF":6.8,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11127357/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141094531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-05DOI: 10.1186/s41479-024-00130-2
Alexander J Adamson, Constantinos Kallis, Ian Douglas, Jennifer K Quint
Background: In primary care, identifying pneumonia events in people with chronic obstructive pulmonary disease (COPD) may be challenging due to similarities in symptoms with COPD exacerbations and lack of diagnostic testing. This study explored the accuracy of pneumonia diagnosis coded in primary care by comparing diagnosis in primary care with diagnosis in hospital.
Methods: A study population of people with COPD in England was created using the Clinical Practice Research Datalink Aurum database linked with Hospital Episode Statistics inpatient data. Pneumonia codes only, and pneumonia code with associated clinical and/or treatment codes (chest x-ray, symptoms, antibiotics, sputum and blood culture) were used to determine pneumonia events in primary care. Events that were followed by hospitalisation within 7 days were used to estimate the positive predictive value (PPV) of pneumonia coding in primary care, using primary diagnosis of pneumonia in secondary care as the gold standard. The PPV of primary care recording of hospitalised pneumonia was also calculated.
Results: Two hundred seventy-four thousand one hundred fifty-six COPD patients were eligible for inclusion, of whom 7,560 had an eligible pneumonia event in primary care diagnosed between 2015-2019 which was not 'hospital-acquired' and was diagnosed and entered on the same day. Of the 2,094 events which were followed by hospitalisation within 7 days, 1,208 had a primary diagnosis of pneumonia in hospital, representing a PPV of pneumonia coding in primary care of 57.7% (95% CI 55.6%-59.8%). Another 284 (13.6%) were diagnosed as a COPD exacerbation and 114 (5.4%) were diagnosed as another respiratory disease. Use of additional pneumonia clinical and treatment codes had a modest effect on the PPV but substantially lowered the number of events. Of the 33,603 eligible pneumonia events identified in secondary care, only 11,445 were recorded in primary care within 42 days, representing a sensitivity of 34.1% (95% CI 33.6%-34.6%).
Conclusions: Use of primary care pneumonia codes and associated clinical and treatment codes to determine pneumonia is not recommended due to significant levels of misdiagnosis and many hospitalised events failing to be recorded in primary care.
{"title":"Accuracy of the recording of pneumonia events in English electronic healthcare record data in patients with chronic obstructive pulmonary disease.","authors":"Alexander J Adamson, Constantinos Kallis, Ian Douglas, Jennifer K Quint","doi":"10.1186/s41479-024-00130-2","DOIUrl":"https://doi.org/10.1186/s41479-024-00130-2","url":null,"abstract":"<p><strong>Background: </strong>In primary care, identifying pneumonia events in people with chronic obstructive pulmonary disease (COPD) may be challenging due to similarities in symptoms with COPD exacerbations and lack of diagnostic testing. This study explored the accuracy of pneumonia diagnosis coded in primary care by comparing diagnosis in primary care with diagnosis in hospital.</p><p><strong>Methods: </strong>A study population of people with COPD in England was created using the Clinical Practice Research Datalink Aurum database linked with Hospital Episode Statistics inpatient data. Pneumonia codes only, and pneumonia code with associated clinical and/or treatment codes (chest x-ray, symptoms, antibiotics, sputum and blood culture) were used to determine pneumonia events in primary care. Events that were followed by hospitalisation within 7 days were used to estimate the positive predictive value (PPV) of pneumonia coding in primary care, using primary diagnosis of pneumonia in secondary care as the gold standard. The PPV of primary care recording of hospitalised pneumonia was also calculated.</p><p><strong>Results: </strong>Two hundred seventy-four thousand one hundred fifty-six COPD patients were eligible for inclusion, of whom 7,560 had an eligible pneumonia event in primary care diagnosed between 2015-2019 which was not 'hospital-acquired' and was diagnosed and entered on the same day. Of the 2,094 events which were followed by hospitalisation within 7 days, 1,208 had a primary diagnosis of pneumonia in hospital, representing a PPV of pneumonia coding in primary care of 57.7% (95% CI 55.6%-59.8%). Another 284 (13.6%) were diagnosed as a COPD exacerbation and 114 (5.4%) were diagnosed as another respiratory disease. Use of additional pneumonia clinical and treatment codes had a modest effect on the PPV but substantially lowered the number of events. Of the 33,603 eligible pneumonia events identified in secondary care, only 11,445 were recorded in primary care within 42 days, representing a sensitivity of 34.1% (95% CI 33.6%-34.6%).</p><p><strong>Conclusions: </strong>Use of primary care pneumonia codes and associated clinical and treatment codes to determine pneumonia is not recommended due to significant levels of misdiagnosis and many hospitalised events failing to be recorded in primary care.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"8"},"PeriodicalIF":6.8,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11070075/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140855560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.1186/s41479-024-00126-y
Patrick Hervé Diboue Betote, Esther Del Florence Ndedi Moni, Sonia Raïssa Gayap Matchuenkam, Sandrine Suzanne Bayengue Beack, Rodrigue Fifen, Raogo Ouedraogo, Gabriel A Agbor, Rasmané Semde, Nga Nnanga, Maximilienne Ascension Nyegue
Background: Klebsiella pneumoniae has become one of the major threats to public health as it causes nosocomial and community-acquired infections like lobar pneumonia. This infection causes acute inflammation in the lung, characterized by the recruitment of polymorphonuclear cells, generating free radicals, and decreasing the endogenous antioxidant balance system. Many experimental studies have focused on the induction, progression and resolution of infection up to its peak, but these documented processes remain highly random and their sex dependence un-elicited. These fluctuations of physiopathological parameters would impact disease progression depending on the animal's model and bacterial strain used. The present study investigated the sex-dependent vulnerability of Wistar rats to K. pneumoniae ATCC 43816 lobar pneumonia induced by the intranasal instillation method.
Methods: Experimental pneumonia was induced by K. pneumoniae ATCC 43816 in male and female Wistar rats following intranasal instillation. The physiopathogenesis of the disease was studied by bacteriological and histopathological exams, histomorphometric analysis of the blood and/or lung tissue, and body weight loss in infected animals. In addition, the overall severity of lesions was determined by the total score obtained by averaging the individual scores from the same group of animals.
Results: The K. pneumoniae ATCC 43816 strain showed inoculation dose-, incubation time of the disease- and sex-dependent- differences in its ability to induce lobar pneumonia. Evaluation of different parameters showed that the disease peaked on day 15 post-inoculation, with more pathogenic effects on female rats. This observed sex-dependence difference in Wistar rats was mainly highlighted by the determined lethal dose 50 (LD50), bacterial load count in whole blood and lung tissues, body weight loss, inflammatory granulomas forming and diffuse alveolar damages. The pathogenicity was confirmed by scoring the severity of pathologic lesions of lung tissues.
Conclusions: The results obtained highlighted the gender-dependency in the physiopathogenesis processes of K. pneumoniae ATCC 43816 induced-lobar pneumonia, in Wistar rats. Female Wistar rats' susceptibility is useful in studying pathology and in preclinical trial investigations of new treatments for infectious pneumonia.
{"title":"Sex-dependent vulnerability for Wistar rats model following intranasal instillation with Klebsiella pneumoniae ATCC 43816 causing lobar pneumonia.","authors":"Patrick Hervé Diboue Betote, Esther Del Florence Ndedi Moni, Sonia Raïssa Gayap Matchuenkam, Sandrine Suzanne Bayengue Beack, Rodrigue Fifen, Raogo Ouedraogo, Gabriel A Agbor, Rasmané Semde, Nga Nnanga, Maximilienne Ascension Nyegue","doi":"10.1186/s41479-024-00126-y","DOIUrl":"10.1186/s41479-024-00126-y","url":null,"abstract":"<p><strong>Background: </strong>Klebsiella pneumoniae has become one of the major threats to public health as it causes nosocomial and community-acquired infections like lobar pneumonia. This infection causes acute inflammation in the lung, characterized by the recruitment of polymorphonuclear cells, generating free radicals, and decreasing the endogenous antioxidant balance system. Many experimental studies have focused on the induction, progression and resolution of infection up to its peak, but these documented processes remain highly random and their sex dependence un-elicited. These fluctuations of physiopathological parameters would impact disease progression depending on the animal's model and bacterial strain used. The present study investigated the sex-dependent vulnerability of Wistar rats to K. pneumoniae ATCC 43816 lobar pneumonia induced by the intranasal instillation method.</p><p><strong>Methods: </strong>Experimental pneumonia was induced by K. pneumoniae ATCC 43816 in male and female Wistar rats following intranasal instillation. The physiopathogenesis of the disease was studied by bacteriological and histopathological exams, histomorphometric analysis of the blood and/or lung tissue, and body weight loss in infected animals. In addition, the overall severity of lesions was determined by the total score obtained by averaging the individual scores from the same group of animals.</p><p><strong>Results: </strong>The K. pneumoniae ATCC 43816 strain showed inoculation dose-, incubation time of the disease- and sex-dependent- differences in its ability to induce lobar pneumonia. Evaluation of different parameters showed that the disease peaked on day 15 post-inoculation, with more pathogenic effects on female rats. This observed sex-dependence difference in Wistar rats was mainly highlighted by the determined lethal dose 50 (LD<sub>50</sub>), bacterial load count in whole blood and lung tissues, body weight loss, inflammatory granulomas forming and diffuse alveolar damages. The pathogenicity was confirmed by scoring the severity of pathologic lesions of lung tissues.</p><p><strong>Conclusions: </strong>The results obtained highlighted the gender-dependency in the physiopathogenesis processes of K. pneumoniae ATCC 43816 induced-lobar pneumonia, in Wistar rats. Female Wistar rats' susceptibility is useful in studying pathology and in preclinical trial investigations of new treatments for infectious pneumonia.</p>","PeriodicalId":45120,"journal":{"name":"Pneumonia","volume":"16 1","pages":"5"},"PeriodicalIF":6.8,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10962189/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140207803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}