Journal of Infection in Developing Countries最新文献

Introduction: Rheumatoid arthritis (RA) remission remains a key treatment goal, but remission rates vary. Emerging evidence suggests that gut microbiota modulation via probiotics may influence systemic inflammation and improve outcomes in RA. The objective was to evaluate the effects of adjunctive probiotic supplementation on clinical outcomes in patients with newly diagnosed RA receiving conventional disease-modifying antirheumatic drugs (cDMARDs) over 12 months.

Methodology: In this randomized, placebo-controlled trial, 100 patients with newly diagnosed RA were assigned to receive either probiotics containing Lactobacillus casei BLn2401, Lactobacillus salivarius BL2201, and Bifidobacterium breve BL3406 plus cDMARDs (experimental group); or cDMARDs alone (control). Clinical outcomes including disease activity score using 28 joints (DAS28), inflammatory markers (C-reactive protein, CRP; erythrocyte sedimentation rate, ESR), pain (visual analogue scale, VAS), functional disability (health assessment questionnaire, HAQ), and RA quality of life (RAQoL) questionnaire were assessed at baseline and follow-up. Remission rates and corticosteroid use were evaluated.

Results: The probiotic group demonstrated faster and more sustained reductions in DAS28, CRP, ESR, pain, and disability scores; compared to controls. The probiotic group achieved near-remission (DAS28 2.3 ± 0.4) by 12 months, while the control group reverted to baseline disease activity. Probiotic use was the independent predictor of remission or low disease activity (HR = 2.703, p < 0.001). Patient-reported quality of life improved significantly, and corticosteroid dependence decreased in the probiotic group.

Conclusions: Adjunctive probiotic supplementation with specific strains may enhance clinical outcomes, reduce inflammation, and increase remission rates in early RA, supporting probiotics as a safe, accessible adjunctive therapy.

Introduction: Sepsis is a major cause of morbidity and mortality in premature infants. Rapid diagnosis and initiation of treatment are of great importance. This study aims to evaluate the role of the Neonatal Sequential Organ Failure Assessment (nSOFA) score in predicting the causal agents and outcomes of late-onset sepsis in preterm neonates.

Methodology: In this single-center, retrospectively designed study, nSOFA scores of preterm infants born before 32 gestational weeks and weighing under 1500 g with a diagnosis of culture-proven late-onset sepsis (LOS) were compared at different timepoints in relation to mortality.

Results: Thirteen of 117 preterms included in the study died. At all the timepoints examined, the median nSOFA score was found to be higher in the mortality group (all p < 0.001). A 3.5 cutoff value of nSOFA showed the best differentiation, with AUC = 0.97 (95% CI: 0.94-1.00), 100% sensitivity, and 91.4% specificity. When nSOFA scores were compared in patients grouped as gram-positive sepsis and gram-negative sepsis, scores at T0, T6, T12, and T24 timepoints were determined to be significantly higher in the exitus group (all p < 0.008). In preterm infants born before 28 gestational weeks, mortality was predicted with the 3.5 cutoff value at T6, T12, T24, and T48 timepoints (AUC = 0.947, 0.943, 0.972, and 0.940, respectively, all p < 0.001).

Conclusions: The results showed that the nSOFA score is useful for predicting sepsis-related mortality in preterm infants and correlates with the severity of gram-negative sepsis.

Introduction: Timely and effective diagnosis plays a pivotal role in schistosomiasis control efforts. This study aims to assess the utility of combined Schistosoma haematobium soluble egg antigen (Sh SEA) and S. mansoni worm antigen (Sm SWA) in serological diagnosis of urogenital schistosomiasis.

Methodology: Admixtures containing 10 µg/mL of both Sm SEA and Sh SEA, as well as Sm SWA and Sh SWA, were employed to detect S. haematobium infection via an indirect enzyme-linked immunosorbent assay (ELISA) using sera and urine from microscopically confirmed positive samples from an endemic population, along with confirmed negative samples from both endemic (NE) and non-endemic (NNE) populations.

Results: The diagnostic performance of Schistosoma eggs and worm antigen mixtures varied depending on sample type and negative endemicity. The Sm SEA and Sh SEA mixtures performed poorly with sera and urine from the pair of positive vs negative endemic samples, as well as positive vs non-endemic samples, but excellently with positive vs negative endemic urine samples pair (sensitivity 91.67%; specificity 66.67%). Conversely, SWA mixtures showed superior performance, particularly with the positive vs negative non-endemic sera samples pair (sensitivity 93.75%; specificity 72.92%). Other SWA-based mixtures, except SWA admixture using urine in positive vs NE samples, exhibited acceptable performance. Antibody titers varied significantly, with higher titers generally observed in negative endemic samples for SWA mixtures and in negative non-endemic urine samples for SEA mixtures (p < 0.05).

Conclusions: Combined antigens improve Schistosoma diagnostics: SEA admixtures suit endemic urine samples, while SWA admixtures aid non-endemic sera detection.

Objective: This study aimed to compare the Helicobacter pylori (Hp) infection rate and serum gastric function among patients with chronic atrophic gastritis (CAG) of different pathological types and to determine the value of combining these tests in assessing the extent and severity of CAG atrophy.

Methodology: We retrospectively analyzed 60 patients with CAG and 46 patients with chronic non-atrophic gastritis (CNAG) who underwent gastroscopy between July 2023 and June 2024. Endoscopic findings, histopathology, Hp status and serum gastric function indices were compared.

Results: Compared with the CNAG group, the CAG group showed a significantly higher Hp positivity rate, lower serum group I pepsinogen (PG I) and group II pepsinogen (PG II) levels and higher gastrin 17 (G-17) levels (p < 0.01). In patients with CAG, open-type cases had a significantly higher Hp positivity rate (p < 0.05), lower PG I and PG II levels and higher G-17 levels (p < 0.01) than closed-type cases. The positive Hp rate was significantly higher in the atrophic gastritis with intestinal metaplasia group than in the glandular reduction atrophic gastritis group (p < 0.05), with the contents of PG I and PG II significantly lower in the former than in the latter and the content of G-17 significantly higher in the former than in the latter (p < 0.01).

Conclusions: Helicobacter pylori infection is strongly associated with CAG, with marked differences in Hp rates and serum gastric function across pathological and microscopic types. Combined serum gastric function and Hp testing can help assess the extent and severity of atrophy.

Introduction: The emergence of extended-spectrum β-lactamases (ESBLs), AmpC β-lactamases, and carbapenemases; and their co-existence among Enterobacterales uropathogens present new diagnostic and therapeutic challenges. This study aimed to elucidate the phenotypic detection and co-occurrence of ESBL-, AmpC-, and carbapenemase-producing uropathogens.

Methodology: A cross-sectional study was conducted from 3 January to 26 July 2024, at the Department of Microbiology, Basic Medical Sciences Institute, in collaboration with the Department of Urology at Jinnah Postgraduate Medical Center and National Medical Centre, Karachi, Pakistan. A total of 260 non-repetitive urine samples were collected from hospitalized and community patients. Antimicrobial susceptibility was determined by disc diffusion; ESBL, AmpC, and carbapenemase producers were identified using the double disc synergy test (DDST), modified three-dimensional method, and lateral flow immunochromatographic (LFI) assay, respectively.

Results: Among the 260 cases, 207 (80%) showed positive growth, yielding 240 isolates. Out of 189 Enterobacterales, E. coli (131; 69.3%) was the most prevalent, followed by K. pneumoniae (46; 24.3%), P. mirabilis (3; 1.6%), E. cloacae (3; 1.6%), K. oxytoca (2; 1.1%), C. freundii (2; 1.1%), C. werkmanii (1; 0.5%), and P. rettgeri (1; 0.5%). There were 89 (47.1%) ESBL producers, 10 (5.2%) AmpC producers, and 59 (31.2%) carbapenem-resistant isolates. New Delhi metallo-beta-lactamase (NDM) was the dominant carbapenemase (33; 56%). Co-production of ESBL and NDM was the most common, and detected in 30 (19%) isolates.

Conclusions: The prevalence of ESBLs and carbapenemase producers was high, with frequent co-production of ESBL and NDM. Rapid, cost-effective phenotypic methods are crucial for timely detection and appropriate antimicrobial treatment.

Introduction: Adherence to guideline-based monitoring (GBM) for chronic hepatitis B (CHB) in China remains understudied. This mixed-methods study assessed GBM adherence and explored patient-reported barriers.

Methodology: A mixed study was conducted at the Zhongshan Hospital (Xiamen), Fudan University, China. Patients visiting the outpatient department of the hospital between January 2018 and December 2018 were included for the quantitative component. Clinical and biochemical data were retrieved from the hospital's electronic medical record system. Adherence to GBM was defined as regular monitoring of alanine aminotransferase (ALT), hepatitis B virus DNA (HBV-DNA), alpha-fetoprotein (AFP), and liver imaging; at least annually during the 2-year follow-up period. The qualitative component involved semi-structured interviews with thematic and content analysis.

Results: Among the 402 eligible CHB outpatients, only 103 (25.6%) patients presented good adherence to GBM. Specifically, 171 (42.5%) patients were monitored at least annually for ALT and HBV-DNA, while 107 (26.6%) were monitored for AFP and liver imaging. The factors associated with adherence to GBM included receiving antiviral treatment (OR = 3.54 (1.59-7.86)) and completing initial liver imaging (OR = 4.78 (2.04-9.83)). The reasons for non-adherence included inadequate monitoring tests and health education by healthcare providers, patients' perception of not needing frequent monitoring, forgetfulness, cost concerns, and complex hospital visit procedures.

Conclusions: Adherence to GBM among CHB patients was suboptimal despite guideline recommendations. Enhanced efforts and interventions, such as combining technology-driven tools, targeted education for providers and patients, and primary care integration are essential.

Introduction: Abortion in livestock can have a significant impact on animal husbandry, as well as raise public health concerns when caused by zoonotic pathogens. Thus, the involvement of bacterial (e.g., Brucella spp. and Enterobacteriaceae) and fungal infections in livestock abortions in Armenia was explored.

Methodology: From 2018 to 2022, 168 aborted foetal tissues from cattle and small ruminants in Armenia were tested for fungal and Enterobacteriaceae infections by culture. The API 20E biochemical test was performed on bacteria-positive samples. Culture-negative samples were further tested by qPCR to detect Brucella DNA. In all qPCR-positive aborted foetuses, maternal blood samples (n = 129) were collected ≥ 30 days post-abortion for serological diagnosis.

Results: Overall, 33 foetal samples were positive by culture: 28 for Aspergillus spp. and 5 for Salmonella spp. Brucella DNA was detected in 129 out of 135 culture-negative samples; in addition, anti-Brucella antibodies were found in 124 maternal blood samples. A total of 6 (3.5%) samples were classified as indeterminate by any assay.

Conclusions: Our results suggest that Brucella is the major cause of abortions in cattle and small ruminants in Armenia, while other bacterial and fungal infections were involved in less than 20% of cases. Based on these findings, it is recommended to test all samples first by serology and qPCR to detect Brucella infections. For Brucella-negative samples, additional methods can be used to detect other abortifacient agents. This protocol will be useful for laboratories that operate at Biosafety Level 2 and are unable to isolate this bacterium.

Introduction: Shedding of Coxiella burnetii through milk is significant, particularly in dairy cattle, making milk a potential source of infection for humans. The aims of this study were to estimate the individual and herd-level prevalence of C. burnetii on dairy cattle, and to assess potential public health risk.

Methodology: The study was conducted as a screening study in 95 randomly selected dairy herds from Montenegro from March to May 2019. No abortions, reproductive disorders, or human diseases were reported in these farms. In order to identify positive farms, anti-C. burnetii antibodies and C. burnetii DNA were detected in bulk tank milk (BTM) using enzyme-linked immunosorbent assay (ELISA) and quantitative polymerase chain reaction (qPCR), respectively. All animals from the positive farms were sampled twice, 2 months apart; the presence of C. burnetii DNA in individual milk samples and the presence of anti-C. burnetii antibodies in milk and blood serum was detected using qPCR and ELISA.

Results: The overall herd-level prevalence of C. burnetii was 9.47% (9/95). Analysis of individual milk samples in the positive farms revealed anti-C. burnetii antibodies and C. burnetii DNA in 13.48% and 4.49% of the cows, respectively. Antibodies were also detected in 15.73% of the blood samples. No significant differences were observed between the results obtained through serological and molecular examination on the same farm two months later.

Conclusions: Although a low presence was detected in the farms, public health risk cannot be excluded. Further research is needed for unravelling the current epidemiological situation in the country.

Introduction: Sub-minimal inhibitory concentrations (sub-MICs) of antibiotics can modulate the expression of virulence factors in bacterial pathogens. This study aimed to assess the impacts of sub-MICs of tedizolid on virulence gene expression in Staphylococcus aureus (S. aureus) and compare them with those of linezolid.

Methodology: Two S. aureus strains (N315 and Newman) possessing the selected virulence genes were analyzed. The MICs of tedizolid and linezolid were determined, and sub-MICs for subsequent experiments were selected based on bacterial growth kinetics. Using qRT-PCR, we assessed the expression of 23 virulence genes, including 7 cell wall-anchored (CWA) protein genes, 4 exoenzyme genes, 6 toxin genes, and 6 regulatory genes, before and after exposure to tedizolid and linezolid.

Results: Growth kinetics indicated that 1/8 and 1/4 MICs were optimal for evaluating the influence of drugs on gene expression. The qRT-PCR results revealed that sub-MICs of tedizolid and linezolid primarily enhanced the expression of the studied virulence genes in both strains. In Newman, tedizolid upregulated the expression of more genes encoding CWA proteins, regulators, and toxins than linezolid. In N315, tedizolid stimulated the expression of more toxin-coding genes but fewer regulatory genes compared to linezolid.

Conclusions: Sub-MIC of tedizolid and linezolid could increase the mRNA levels of different types of virulence genes in S. aureus, with strain-dependent variations. These findings provide new insights into the potential role of oxazolidinones in bacterial virulence regulation.

Introduction: Transmission of parasitic agents through transfusion can endanger the availability of safe blood and blood components for patients in need. The aim of this research was to describe the current status of transfusion-transmitted parasitic infections (TTPIs) in Iran and propose strategies to minimize their transmission risk.

Methodology: This narrative review included all studies that estimated the prevalence of TTPIs in Iranian blood donors based on parasitological, serological, and molecular techniques. A literature search was conducted for the period between 1960 and 2023 using medical subject headings (MeSH) terms in 11 English and Persian electronic databases. The extracted data were recorded on a pre-prepared checklist, and analyzed using SPSS.

Results: Twenty-nine studies were eligible for inclusion. A total of 12,643 blood donors were examined for malaria, visceral leishmaniasis (VL), and toxoplasmosis in endemic and non-endemic areas. The overall serological prevalence of malaria, Leishmania infantum, and Toxoplasma gondii infections among blood donors was 9.60%, 1.96%, and 35.75%, respectively. The results of molecular techniques were positive in 0.71%, 39.22% (only seropositive samples), and 8.73% for malaria, VL, and toxoplasmosis, respectively.

Conclusions: Considering the detection of parasitic DNA causing malaria, VL, and toxoplasmosis; and the presence of anti-T. gondii IgM antibodies among Iranian blood donors; their transmission through blood and blood components transfusion cannot be ruled out, particularly in endemic areas. Therefore, it is essential to adopt and implement appropriate strategies to minimize the risk of TTPIs and ensure the availability of safe and sufficient blood and blood components for patients in need.