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Oesophageal aspergillosis is a rare occurrence primarily documented in hematologic malignancies, and only rarely occurring among patients with solid tumours. In this case report, we present the unique case of an 81-year-old Lebanese man who had a remarkable medical history, including four solid tumours. The patient sought medical attention due to dysphagia and weight loss, prompting a gastroscopic examination that revealed a necrotic abscess at the oesophagogastric junction. Initial treatment with fluconazole and esomeprazole was administered, but the recurrence of similar symptoms led to a repeat gastroscopy, unveiling a diagnosis of Aspergillus oesophagitis. Intravenous voriconazole was promptly initiated; however, the patient developed a significant pericardial effusion and expired, with Aspergillus species identified in the pericardial fluid prior to patient expiring. This exceptional case emphasizes the importance of considering oesophageal aspergillosis in cancer patients who present with refractory symptoms such as epigastric pain, dysphagia, nausea, and vomiting, despite symptomatic treatment. Our findings underscore the need for increased awareness and the inclusion of gastrointestinal endoscopy as part of the diagnostic approach for this rare but potentially life-threatening condition.

Acute respiratory infections (ARIs) are a serious public health concern across the world, causing considerable morbidity and mortality. Every year, around 13 million children under the age of five die. Approximately 95% of them are from developing nations, and ARIs are responsible for one-third of all deaths. Human Metapneumovirus (hMPV) is one of the causative agents associated with respiratory tract infections. There is lack of information about hMPV from the eastern region of Uttar Pradesh. At Indian Council of Medical Research- Regional Medical Research Centre, Gorakhpur (ICMR-RMRC, Gorakhpur) in Uttar Pradesh, India; we tested respiratory pathogens in under-five patients presenting with ARI and severe acute respiratory illness (SARI) through semi nested PCR. A total of 100 nasal and throat specimens were collected from the outdoor and indoor patient Departments (OPD) and (IPD) of Department of Paediatrics, BRD Medical College, Gorakhpur during February to April 2022. Out of 100 enrolled paediatric patients, 4(4%) were found to be hMPV positive. Among the patients who tested positive for hMPV, 25%(1/4) unfortunately died. The phylogenetic analysis of hMPV showed the close resemblance with the clade of Singapore and USA hMPV isolates. The study underlines the importance of hMPV as the cause of acute respiratory infections in children and the highlight the need for routine testing for this virus in laboratories. Further more comprehensive detailed study on various aspects of hMPV in this area is needed.

The Bad Bugs Bookclub is a public engagement initiative that enables scientists (microbiologists) and non-scientists to discuss the role of infectious disease and microorganisms in novels of fiction. The bookclub began in 2009, but since 2020, the meetings have taken place online, enabling international membership and occasional author participation. The bookclub has been shown, through peer-reviewed publications, to have impact and value to its members. For each book (the number now exceeds 100), a reading guide (questions to provoke discussion) and a meeting report (narrative of the discussion) were produced. Previously hosted on a website, the reading guides from this rich archive and resource are now presented alongside this paper, which provides tips on how to run a similar reading group.

Present case report describes a case of an atypical oesophageal actinobacillosis in an adult cow presented to the university hospital with a history of inability to drink and swallow. Clinical examination revealed a five-inch swelling in the jugular groove. Skiagram revealed the presence of a small and slightly radio opaque round growth. Exploratory surgical excision of the growth was adapted as palliative treatment and the extirpated tissue was fixed in 10% buffered formalin. Histopathological examination revealed pyogranulomatous inflammation with radiating eosinophilic club shaped bodies surrounding small colonies of coccobacilli. Gram and Ziehl-Neelsen stains confirmed the presence of Gram-negative and non-acid-fast coccobacilli. Histopathology confirmed the pathognomonic lesion and proved to be a modality of choice for pathologists to reach at a diagnosis of atypical oesophageal actinobacillosis in a cow. After the exhaustive search of relevant literature on atypical actinobacillosis, the authors claim this to be the second report of oesophageal actinobacillosis worldwide.

In 2011, a novel methicillin resistance gene, mecC, was described in human and bovine Staphylococcus aureus isolates. mecC-positive S. aureus is most commonly associated with livestock and wildlife populations across Europe and is particularly prevalent in hedgehogs, but only occasionally causes human infections. In this study, we characterize and investigate the origin of two human S. aureus isolates containing mecC genes from New Zealand. The two isolates were identified from patients with severe invasion infections as part of an S. aureus bacteraemia study. Whole-genome sequencing was used to characterize staphylococcal cassette chromosome mec (SCCmec) elements and perform phylogenetic comparisons with publicly available strains from mecC-associated clonal complexes, including isolates from hedgehogs from New Zealand and Europe/United Kingdom (UK), and livestock, wildlife and human isolates from Europe/UK. The two isolates from our study have almost identical SCCmec type XI elements containing a mecC gene. However, this gene contains a premature stop codon, consistent with the methicillin-susceptible phenotype observed for these isolates. Core genome SNP analyses showed that the two isolates are 234 SNPs apart and are most closely related to an isolate obtained from a New Zealand hedgehog. However, there are considerable differences in the mecC mobile element between the human and hedgehog isolates, indicating the presence of an as-yet-unknown reservoir of mecC S. aureus in the New Zealand environment.

Introduction. Mycobacterium tuberculosis (MTB) infections continue to have a high mortality and morbidity burden globally. Interferon-gamma release assays such as Quantiferon Gold Plus (QFG-Plus) aid in diagnosis of latent TB but diagnosis of pleural TB remains challenging. We present a case of active pleural MTB infection with reversion from positive to negative of IGRA result as well as negative Xpert MTB/RIF Ultra PCR result from tissues obtained from pleural biopsy. Case summary. A 52-year-old otherwise healthy male presented in August 2022 with a 2 week history of pleuritic chest pain associated with modest elevation in inflammatory markers. The patient had had a positive QFG-Plus result in 2018, however QFG-Plus during this admission was negative. Computed-tomography pulmonary angiogram and needle thoracocentesis showed an exudative left pleural effusion with predominant lymphocytes. The patient's symptoms failed to resolve with empiric antimicrobial therapy for community-acquired pneumonia. Broncho-alveolar lavage as well as biopsies of pleural tissues via video-assisted thoracoscopic surgery from the left lower lobe yielded negative results on routine microbiological culture as well as Xpert Ultra PCR. Growth of acid-fast bacilli was noted from mycobacterial cultures of pleural tissues which was identified as MTB. Conclusion. Despite significant technological advances, microbiological diagnosis of MTB infections remains challenging. We document QFG-Plus reversion during development from latent to active pleural TB. Decline in the ability of CD4⁺ and CD8⁺ T cells to produce interferon gamma in response to TB antigens (ESAT-6 and CFP-10) was likely associated with loss of host control of latent MTB. This case serves as a reminder that despite exhaustive testing with state-of-art diagnostic platforms, MTB infections can still elude discovery.

Auxins, mainly in the form of indole-3-acetic acid (IAA), regulate several aspects of plant and algal growth and development. Consequently, plant and algae-associated bacteria developed the ability to modulate IAA levels, including IAA catabolism. In this work, we present and analyse the genome sequence of the IAA-degrading and marine algae-associated bacterium, Marinomonas sp. NFXS50, analyse its IAA catabolism gene cluster and study the prevalence of IAA catabolism genes in other Marinomonas genomes. Our findings revealed the presence of homologs of the Pseudomonas iac gene cluster, implicated in IAA catabolism, in the genome of strain NFXS50; however, differences were observed in the content and organization of the Marinomonas iac gene cluster when compared to that of the model iac-containing Pseudomonas putida 1290. These variations suggest potential adaptations in the IAA catabolism pathway, possibly influenced by substrate availability and evolutionary factors. The prevalence of iac genes across several Marinomonas species underscores the significance of IAA catabolism in marine environments, potentially influencing plant/algae-bacteria interactions. This study provides novel insights into the IAA catabolism in Marinomonas, laying the groundwork for future investigations into the role of iac genes in Marinomonas physiology and the regulation of marine plant/algae-bacteria interactions.

Objectives. This study aimed to determine patterns of respiratory, blood-borne and uropathogenic microbial pathogens among SARS-CoV-2-infected patients in a COVID-19-(coronavirus disease 2019) dedicated tertiary care hospital in Dhaka, Bangladesh. Design.This was a cross-sectional study. Setting. In a COVID-19-dedicated tertiary care hospital in Dhaka, Bangladesh, conducted from March to June 2021. Participants. Hospitalized individuals with COVID-19 infection regardless of age or sex. Primary and secondary outcome measures. The percentage of co-infected COVID-19 patients and the characterization of the micro-organisms responsible for co-infection served as the primary outcome measures. Finding any associations between co-infection and age, co-infection and sex and co-infection and comorbidity was the secondary outcome variable. Interventions. Not applicable. Results.Out of 79 patients, 61 % were male, and the mean age was 49.53 years. Co-infection was seen in 7.7 % of patients, out of which 5.1 % of isolates were from urine samples, followed by 2.6 % from blood. Bacteria isolated from urine were Enterococcus (2.6 %), coagulase-negative Staphylococcus (CONS) (1.3 %) and Enterobacter spp. (1.3 %). Pseudomonas spp. was the only organism isolated from blood sample. Mixed growth was found in nasopharyngeal and throat swabs, with the predominant species being Staphylococcus aureus and Streptococcus spp. At the time of data collection, 55.7 % of patients had been given antimicrobials, and 30.4 % of patients had been given a single antimicrobial. HBsAg was positive in 1.3 % of patients and none were anti-hepatitis C or dengue NS1Ag positive. Conclusion. Microbial infection has been seen to be associated with SARS-CoV-2 infections and is of great value in prescribing antimicrobials and reducing fatal outcomes of hospitalized patients.

Papillomaviruses (PVs) are double-stranded, circular, epitheliotropic DNA viruses causing benign warts (papillomas) or inducing dysplasia that can progress to cancer. Although they have been identified in all vertebrate taxa, most classified types are human PVs (HPVs); relatively little is known about PVs in other species. Here we characterize a novel Gammapapillomavirus type, PtepPV1, from a nasal swab of a wild red colobus (Piliocolobus tephrosceles) in Kibale National Park, Uganda. The virus has a genome of 6576 bases, encoding the seven canonical early (E) ORFs (E6, E7, E1, E2, E4, E1^E4 and E8^E2) and two late (L) ORFs (L1 and L2) of the gammapapillomaviruses, and is 81.0% similar to HPV-mSK_118, detected in a cutaneous wart from an immunocompromised human patient, in the L1 gene at the amino acid level. Alphapapillomaviruses (genus Alphapapillomavirus) cause anogenital carcinomas such as cervical cancer and have been described previously in several nonhuman primates. However, the first gammapapillomavirus (genus Gammapapillomavirus), which cause transient cutaneous infections, was not described until 2019 in a healthy rhesus macaque (Macaca mulatta) genital swab. The new virus from red colobus, PtepPV1, has many genomic features encoded by high-risk oncogenic PVs, such as the E7 gene LXSXE and CXXC motifs, suggesting potential for pRb and zinc-finger binding, respectively. To our knowledge, PtepPV1 is also the first reported nonhuman primate PV found in the nasal cavity. PtepPV1 expands the known host range, geographical distribution, tissue tropism and biological characteristics of nonhuman primate PVs.

Introduction. Mycotic aneurysms, characterized by vessel wall dilation resulting from infections including bacteria, fungi, and viruses, are a rare but severe consequence of systemic infections. The term 'mycotic' was coined by William Osler to describe the first instance of a fungal-induced infected aneurysm. These aneurysms, accounting for 0.6% of aneurysms in Western countries, carry a higher risk of rupture compared to uninfected aneurysms. While the femoral artery, aorta, and intracranial arteries are commonly affected, pathogens causing mycotic aneurysms vary across regions. Diagnostic challenges arise from nonspecific symptoms such as fever, and discomfort. To prevent the substantial morbidity and mortality associated with mycotic aneurysms, timely identification and treatment are paramount. We present a case series highlighting mycotic aneurysms caused by some rare pathogens - Salmonella Paratyphi A, Streptococcus pneumoniae, and Pseudomonas aeruginosa. Methods. This case series involves three patients diagnosed with mycotic aneurysms due to unusual pathogens. We describe each patient's clinical presentation, medical history, physical examination findings, laboratory results, imaging studies, and the diagnostic process leading to the identification of the causative pathogens. Results. The first patient is a 70-year-old gentleman who presented with a ruptured infra-renal abdominal aortic pseudoaneurysm caused by Salmonella Paratyphi A. The second patient is a 66-year-old gentleman with a Streptococcus pneumoniae-associated descending thoracic aortic pseudoaneurysm. The third patient is a 70-year-old gentleman with a ruptured descending thoracic aortic aneurysm with an occult aorto-oesophageal fistula due to Pseudomonas aeruginosa infection. The description highlights unique clinical features, laboratory findings, imaging results, and the management approaches undertaken in each patient. Conclusion. Mycotic aneurysms, pose diagnostic challenges due to their nonspecific symptoms. Early identification and intervention are essential to mitigate the severe complications associated with these aneurysms. The presented cases underscore the need for a comprehensive approach to diagnosis and management, ensuring optimal outcomes for patients affected by mycotic aneurysms.