Indian Journal of Medical Microbiology最新文献

Diagnosing fastidious organisms like Legionella pneumophila is difficult in peripheral laboratories due to the unavailability of specialized media such as BCYE agar and the delayed results of serological tests, which are mainly epidemiological. Rapid multiplex PCR platforms, such as the BioFire® Pneumonia Panel, enable timely detection of rare pathogens including L. pneumophila. A 45-year-old female with fever, chest pain, breathlessness, and productive cough was admitted with pneumonia and sepsis. BioFire testing of a mini-BAL sample confirmed L. pneumophila. Early molecular diagnosis ensures targeted therapy, improves outcomes, and supports antimicrobial stewardship.

Invasive fungal infection (IFI) simultaneously due to three fungi is rare. IFI caused by two fungal agents is relatively commoner in transplant patients. Most common IFI worldwide is candidiasis, whereas in India, aspergillosis and mucormycosis infections are commoner. Severe dengue viral infection has been linked with invasive fungal infections. Following case report exemplifies more than two fungi can together cause pneumonia as confirmed by similar findings in 3 respiratory samples from the dengue shock syndrome patient. High clinical suspicion and prompt initiation of aggressive, high-dose, guideline-recommended antifungal therapy is essential at the slightest doubt of mucormycotic pneumonia.

Purpose: The interplay between the local microbiome and inflammatory environment is crucial in modulating the immune response. This research addresses the paucity of studies in the Indian context by mapping the cervical microbiome and associated inflammatory milieu in 43 apparently healthy women and evaluating its perturbations with various asymptomatic vaginal infections.

Methods: Cervical microbiome was mapped for forty three participants, aged 18-45, who were enrolled from a community clinic as a part of longitudinal contraceptive study from October 2021 to September 2023. Sociodemographic data, clinical history, and cervical and cervicovaginal lavage specimens were collected. Microbiome analysis involved nanopore sequencing of the entire 16S rRNA region amplicon, while cytokine assessment in cervicovaginal lavage specimens utilized multiplex immunoassays.

Results: Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, and Fusobacteria appeared as dominant phyla with 32.55% having asymptomatic bacterial vaginosis (BV),16.27% asymptomatic Candida, and 13.95% coinfections. The cervical microbiome was dominated by Lactobacillus iners (45.69%), followed by Lactobacillus helveticus (6.53%) and Lactobacillus reuteri (5.86%). Women with BV exhibited an increased abundance of Prevotella and Streptococcus, while Candida infections were associated with elevated Atopobium and Collinsella species. Pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-8) showed variable levels, with Lactobacillus positively correlating with the regulatory cytokine TNF-α in in Candida infections. In BV Lactobacillus species such as L. agilus, L.iners and L. salivarius showed positive correlation with TNF-α. Additionally, Lactobacillus manihotivoranswas negatively associated with IL-1β, while Lactobacillus brevis and Lactobacilluszeae showed negative correlations with IL-8 .

Conclusion: This study maps the cervical microbiome and cytokine profile of healthy Indian women and demonstrates that asymptomatic bacterial vaginosis and Candida infections induces variations, highlighting the complex host-microbe interactions that govern vaginal health.

Melioidosis, caused by Burkholderia pseudomallei, is an emerging infection in the tropics. Most of the melioidosis patients have underlying co-morbidities or occupational exposures. Hemoglobinopathies, such as thalassemia, are established risk factors for melioidosis; however, the association of SCD with melioidosis is infrequently reported. We report two culture-confirmed melioidosis cases from eastern India: a 58-year-old male with SCD on hydroxyurea and another 44-year-old with sickle cell trait, both presenting with cavitary lung lesions mimicking tuberculosis. SCD-related functional asplenia may heighten susceptibility. These cases emphasise the need for clinical vigilance in endemic areas and further research into SCD/SCT-associated immune vulnerabilities.

Background: Enteric fever remains a major health problem in India. Continuous monitoring of antimicrobial resistance (AMR) is essential to guide therapy and control emerging threats.

Methods: This study aims at analysing the data of Salmonella isolates reported in Delhi NCR over past five years (2020-24). The study has data from 24 laboratories participating in the antimicrobial resistance surveillance network of Delhi. The identification of pathogen and antimicrobial susceptibility testing was performed in each lab using standard methods and the data was compiled and collated using WHONET software and shared to the network on a monthly basis.

Results: A total of 10,689 isolates were analysed: 8371 (78.3%) S. Typhi; 2295 (21.5%) S. Paratyphi A; and 23 (0.2%) S. Paratyphi B. Annual isolates rose from 522 (during 2020) to 3679 (during 2024). Children aged 1-12 years accounted for 46% of cases. Over 5 years period, among S. Typhi, resistance declined for ampicillin (9.6% to 4.1%) and trimethoprim-sulfamethoxazole (8.7% to 3.5%).Chloramphenicol resistance remained ≤5.3%, however, ciprofloxacin non-susceptibility persisted (≈48-60%). Ceftriaxone resistance was rare (3 isolates). Multidrug resistance fell to 1% by 2024. S. Paratyphi A showed similar but generally lower resistance to first-line drugs, yet higher fluoroquinolone resistance (88-98%). No isolate was confirmed by nodal centre as being resistant to azithromycin or carbapenems.

Conclusion: Susceptibility to traditional first-line agents is improving, and multidrug resistance is low; however, fluoroquinolone resistance remains high. Ongoing AMR surveillance and prudent antibiotic use are essential to sustain treatment efficacy.

Background: The emergence of multidrug-resistant (MDR) strains, including those producing metallo-β-lactamases (MBL), necessitates the development of effective therapeutic strategies. The combination of ceftazidime-avibactam (CZA) and aztreonam (ATM) has shown promise as a potential treatment option. This study aimed to evaluate practical and accessible antimicrobial susceptibility testing (AST) methods for assessing the synergy of CZA and ATM in carbapenemase-producing Enterobacterales species, particularly in resource-limited settings with high patient volumes.

Methods: This cross-sectional study was conducted at a tertiary care hospital in Central India from October 2023 to July 2024. It compared different synergy testing methods to the gold-standard broth microdilution (BMD) method in genotypically confirmed carbapenemase-producing isolates. The study evaluated various synergy methods, such as the E-strip, disk replacement, inverse D-zone, and disk approximation.

Results: Of the 60 Enterobacterales isolates, most carried the bla_NDM gene (88.33%, 53/60). Using the BMD method, 73.33% (44/60) of the isolates showed synergy between CZA and ATM. The E-strip method was found to have almost perfect agreement (κ = 1) with BMD, making it highly reliable. However, it may be impractical for high-volume laboratories due to cost and complexity. On the other hand, the disk replacement and inverse D-zone methods demonstrated high sensitivity and specificity, with perfect (κ = 0.874) and substantial (κ = 0.803) agreement with BMD, respectively, providing more practical and cost-effective alternatives. However, the disk approximation method showed lower sensitivity and moderate agreement with BMD (κ = 0.510), making it less reliable.

Conclusion: The combination of CZA and ATM demonstrated significant synergistic results in MBL and serine carbapenemase-producing Enterobacterales species. The disk replacement and inverse D-zone methods are feasible and cost-effective for CZA and ATM synergy testing in routine AST within resource-limited settings, guiding treatment decisions.

There is recent resurgence in incidence of congenital syphilis (CS) in developing and developed countries. Diagnosis of CS can be difficult because approximately two-thirds infants affected are asymptomatic at birth. Pseudoparalysis due to bony pain is often not a sign but symptom, obvious not only to healthcare providers but also parents. We report a case of CS, observed to have excessive crying episodes on handling with no obvious changes on radiograph. Evaluation with 'SCORTCH' profile clinched the diagnosis. Neonate was treated with ceftriaxone due to non-availability of crystalline or procaine penicillin with good outcome at 1year of age.

Purpose: Acute respiratory infections (ARIs) are a major global health concern, causing over 4 million deaths annually, particularly in developing countries. Traditional diagnostic methods, such as microbial culture, are slow, leading to delayed treatment and increased antimicrobial resistance (AMR). This study evaluates the BIOFIRE Pneumonia Plus panel, a multiplex PCR-based assay, for detecting bacterial and viral pathogens and AMR genes in bronchoalveolar lavage (BAL) specimens.

Methods: A method-comparison study was conducted in a tertiary care setting using identified clinical data over one year. BAL specimens were analyzed using the BIOFIRE Pneumonia Plus panel and standard culture, and their results and turnaround times were compared.

Results: Among 303 specimens, the BIOFIRE Pneumonia Plus panel detected pathogens in 70.3 % of cases, significantly outperforming standard culture (14.85 %). The most frequently identified bacteria were Pseudomonas aeruginosa (20.08 %), Klebsiella pneumoniae (17.15 %), and Haemophilus influenzae (16.31 %). The most common viruses detected were human rhinovirus/enterovirus (18.81 %) and influenza A (9.24 %). AMR genes were found in 24.09 % of cases, with CTX-M and NDM being the most prevalent. The BIOFIRE panel provided results in 2 h 35 min, compared to 56 h 46 min for standard culture.

Conclusion: The BIOFIRE Pneumonia Plus panel enables rapid and accurate pathogen detection, improving clinical decision-making and supporting antimicrobial stewardship. Despite limitations such as the detection of colonizers or non-viable microorganisms, it is a valuable tool for enhancing ARI diagnostics and guiding targeted therapy.