Spectrum of Bacterial Pathogens in Critical COVID-19 Patients Admitted in Intensive Care Units of a Tertiary Care Hospital During the First and Second Wave of the Pandemic

Objective: This study intends to compare the clinical characteristics and the prevalence and spectrum of bacterial pathogens in COVID-19 patients admitted to ICU during the first and second waves at a tertiary care, teaching and referral hospital of eastern India. Method: This is a hospital-based retrospective study which analysed demographic details, clinical profile and bacterial culture results of severe and critically ill COVID-19 patients admitted in intensive care units (ICU) during April -Oct 2020 (1 st wave) and April –July 2021 (2 nd wave). Result: The patients admitted during the 2 nd wave were comparatively older and had multiple comorbidities compared to the 1 st wave. (23.8%) (45/189) and 50% (173/346) of the COVID-19 patients admitted to ICU developed bacterial infection during the 1 st and 2 nd wave respectively. Overall, there was predominance of multidrug resistant Gram negative bacilli in both the waves. There was increased isolation of intrinsic colistin resistant microorganisms. Conclusion: Multidrug resistant Gram negative bacterial infections, remain a dreaded complication in severe and critically ill hospitalised COVID-19 patients requiring ICU care and high usage of colistin spirals the emergence and spread of pathogens intrinsically resistant to colistin.

Neonatal septicaemia caused by diverse clones of Klebsiella pneumoniae & Escherichia coli harbouring blaCTX-M-15.

Background & objectives: Information about the genetic diversity of the extended-spectrum β-lactamases (ESBLs) and the clonal relationship of the organisms causing neonatal infections is limited, particularly from India where neonatal mortality is high. This study was undertaken to investigate the molecular epidemiology and risk factors associated with neonatal septicaemia caused by ESBL-producing Klebsiella pneumoniae and Escherichia coli. Methods: Bloodstream isolates (n=26) of K. pneumoniae (n=10) and E. coli (n=16) from the neonates admitted in a tertiary care hospital in New Delhi during January to May 2008 were characterized. Antimicrobial susceptibility tests were carried out and ESBL production was assessed phenotypically. PCR was carried out for ESBL and ampC genes. Genotyping was performed by pulsed-field gel electrophoresis (PFGE). Conjugation experiments were done to determine the mobility of ESBL genes. Risk factors associated with ESBL-producing K. pneumoniae and E. coli infections were analysed. Results: Resistance rates to most of the antibiotics tested were high, except for imipenem. Among the isolates tested, 60 per cent of K. pneumoniae and 75 per cent of E. coli were ESBL producers. PFGE of the isolates demonstrated a vast diversity of genotypes with no epidemic clones. Despite the clonal diversity, blaCTX-M-15 was detected in 100 per cent of ESBL-positive isolates. The other genes present in ESBL-positive isolates were blaTEM-1, blaSHV-1, blaSHV-28, blaSHV-11, and blaSHV-12. Class 1 integrons were detected in 7 of 18 ESBL-positive isolates. Moreover, the plasmid carrying blaCTX-M-15, in E. coli and K. pneumoniae were self transferable. Feeding through an enteral tube was identified as the only risk factor for sepsis by ESBL-producing organisms. Interpretation & conclusions: The study emphasises the presence of blaCTX-M-15 in clonally diverse isolates indicating probable horizontal transfer of this gene. The widespread dissemination of CTX-M-15 is of great concern as it further confines the limited therapeutic interventions available for neonates.

Interobserver variation in the interpretation of Nugent scoring method for diagnosis of bacterial vaginosis.

Background & objectives: Bacterial vaginosis (BV) is the most common form of vaginal infection and an important cause of morbidity in women of reproductive age. This study was carried out to examine the interobserver variation on interpretation of Nugent scoring method in the diagnosis of BV. Methods: This prospective study was conducted in a rural primary health care center of north India from May 2003 to April 2004 and included 601 married, sexually active women between 18-49 yr of age presented with self-reported symptoms of vaginal discharge and/or genital itching and/or genital burning. Specimens collected from the lateral wall of vagina were subjected to Gram staining and the microscope slide smears were examined by 3 independent observers. Each of the three observers scored and interpreted the slides for diagnosis of bacterial vaginosis using the Nugent method. Results: Complete agreement amongst the three observers was found in 76.2 per cent of cases. In 22.13 per cent cases, two observers were in agreement while interpretation of the slides were in complete disagreement only in 1.66 per cent of cases. The interrater reproducibility was found to be excellent between observers 1 and 3, while between observers 1 and 2, and 2 and 3 it was good to fair. Interpretation & conclusions: Nugent scoring system appears to be a reliable and convenient method for laboratory evaluation of cases of bacterial vaginosis. At the same time, one must be aware of the factors that might lead to discrepant results.

Prevalence & susceptibility to fluconazole of Candida species causing vulvovaginitis.

BACKGROUND & OBJECTIVE: Vulvovaginal candidiasis is an important cause of morbidity in women of reproductive age. This study was carried out to determine the species prevalence and susceptibility pattern to fluconazole of yeasts isolated from the vagina of symptomatic women. METHODS: This prospective study was conducted in a rural primary health care center of north India from May 2003 to April 2004 and included 601 married, sexually active women (18-49 yr) with the self reported symptoms of vaginal discharge and/or genital itching and/or genital burning. Specific aetiology of the genitourinary symptoms including candidal infection were determined. Specimens from the lateral wall of vagina were subjected to direct wet mount microscopy and fungal culture on Sabouraud's dextrose agar. Susceptibility testing to fluconazole was carried out using broth microdilution method. RESULTS: Yeasts were isolated in 111 (18.5%) women and these consisted of Candida glabrata (56, 50.4%), C. albicans (39, 35.1%), C. tropicalis (12, 10.8%), C. krusei (3, 2.7%) and C. parapsilosis (1, 0.9%). Susceptibility testing carried out on 30 representative isolates (15 C. glabrata, 10 C. albicans, 4 C. tropicalis and 1 C. parapsilosis) revealed that 21 isolates (70%) were susceptible (MIC, < or = 8 microg/ml) to fluconazole while 9 (30%) were susceptible-dose dependent (S-DD, MIC 16-32 microg/ml). INTERPRETATION & CONCLUSION: Our findings suggest a low prevalence of fluconazole resistance in vaginal candida isolates in our population. However, a high prevalence of non-albicans candida species and increased dose-dependent resistance in these isolates necessitates vigilance since this may warrant a change in the optimal therapy of non-albicans candida vaginitis.

InPouch TV culture for detection of Trichomonas vaginalis.

BACKGROUND & OBJECTIVE: Trichomonas vaginalis accounts for almost half of all curable sexually transmitted infections and has also been associated with adverse outcomes of pregnancy and increased risk of HIV in women. Diagnosis of the condition by direct wet mount examination has a low sensitivity. Herein, we describe our experience with InPouch culture system for the detection of T. vaginalis. METHODS: This prospective study was carried out from May 2003 to April 2004 among women presenting with genitourinary symptoms attending a primary health center clinic in Ballabhgarh, India. Two vaginal swabs (cotton tips) were obtained from each woman. The first swab was obtained from the lateral wall of vagina and was used to make a wet mount preparation. The second swab was obtained from the posterior fornix of the vagina and inoculated in the InPouch for culture of T. vaginalis. RESULTS: Of the 601 women, 22 were positive by direct microscopy for T. vaginalis while 40 were positive by culture. Overall, T. vaginalis accounted for 6.7 per cent of reproductive tract infections. INTERPRETATION & CONCLUSION: The InPouch TV culture system is a simple, cost-effective and a sensitive method for diagnosing T. vaginalis and may be recommended for routine use in diagnosing genital tract infections.

Emerging resistance to carbapenems in a tertiary care hospital in north India.

BACKGROUND AND OBJECTIVES: Carbapenems are beta-lactam antibiotics, presently considered as most potent agents for treating multi-drug resistant Gram-negative bacilli infections. In India carbapenems available for use are meropenem and imipenem, introduced recently. Resistance to these has been reported in a few bacteria especially Pseudomonas spp. We therefore retrospectively evaluated the antibiotic susceptibility pattern to these agents amongst various clinical isolates in a tertiary care hospital in north India. METHODS: In this study Gram-negative bacterial pathogens isolated from clinical samples were tested for extended spectrum beta lactamase (ESBL) production. All ESBL positive bacteria were tested for meropenem and imipenem activity pattern using NCCLS guidelines. A total of 2626 consecutively isolated Gram-negative bacteria, which tested positive for ESBL production by the double disk diffusion method, were included. RESULTS: The different bacteria isolated were Pseudomonas spp. 759, Acinetobacter spp. 676, Escherichia coli 569, Klebsiella spp. 343, Enterobacter spp. 150, Citrobacter spp. 57 and Proteus spp. 72. Overall resistance to meropenem was more (22.16%) than imipenem (17.32%). Maximum resistance was seen in Pseudomonas spp. M(R) 37.6 per cent, I(R) 30 per cent. In isolates from intensive care units (ICU) resistance to carbapenems was significantly higher than non-ICU patients. INTERPRETATION AND CONCLUSION: Resistance to meropenem and imipenem was seen in various clinical isolates of Gram-negative ESBL-positive bacteria. There is a need to alarm our clinicians for judicious use of antibiotics.

Case report vancomycin -resistant Enterococcus faecium VanA phenotype: first documented isolation in India.

In recent years, vancomycin-resistant enterococci, especially Enterococcus faecium has emerged as an important nososcomial pathogen and represents a serious threat to patients with impaired host defences. We report infection with vancomycin-resistant Enterococcus faecium in a 3-year-old child with patent ductus arteriosus. The organism, isolated from a central venous catheter tip, exhibited a high-level resistance to vancomycin (minimum inhibitory concentration > or = 256 microg/ ml) and was also resistant to teicoplanin. The child probably died due to sepsis from this highly resistant organism. To the best of our knowledge, this is the first reported isolation of VanA phenotype Enterococcus faecium in India.

Comparative in vitro activity of beta-lactam/beta-lactamase inhibitor combinations against gram negative bacteria.

BACKGROUND & OBJECTIVE: Currently, the use of beta-lactamase inhibitors in combination with beta-lactam antibiotics represents an effective measure to combat a specific resistance mechanism of beta-lactamase producing organisms. Knowledge about the susceptibility profile of bacteria to different combination agents available is essential to guide appropriate treatment of severe infections in hospitalized patients. The present study compares the in vitro activity of three commercially available beta-lactam/beta-lactamase inhibitor combinations (piperacillin/tazobactam, cefoperazone/sulbactam, ticarcillin/clavulanic acid) against beta-lactamase producing gram negative bacteria in a tertiary care hospital in north India. METHODS: A total of 9004 consecutively isolated extended spectrum beta-lactamase (ESBL) producing gram negative bacteria isolated from various clinical samples from patients admitted to the All India Institute of Medical Sciences, New Delhi, from September 2003 to August 2004 were included in the study. These isolates were screened for ESBL production by the inhibitor based test recommended by the National Committee for Clinical Laboratory Standards (NCCLS). Antibiotic susceptibility testing was carried out by disc diffusion method as per NCCLS guidelines. RESULTS: Of the 9004 isolates tested, 3232 (35.89%) were sensitive and 568 (6.31%) were resistant to all three combination agents, and rest 5204 (57.80%) were resistant to at least one of the combinations. Susceptibility to piperacillin/tazobactam, cefoperazone/sulbactam, and ticarcillin/clavulanic acid was 81.37, 76.06 and 45.48 per cent respectively. Piperacillin/tazobactam exhibited significantly (P<0.05) greater antimicrobial activity against Pseudomonas spp., Escherichia coli and Klebsiella spp. compared to cefoperazone/sulbactam. INTERPRETATION & CONCLUSION: Overall piperacillin/tazobactam was observed to be the best combination agent followed by cefoperazone/sulbactam in our setting. This difference in activities of these combination agents needs to be evaluated further by ascertaining their efficacy in clinical studies.

Species prevalence and antimicrobial susceptibility of enterococci isolated in a tertiary care hospital of North India.

The present prospective study was carried out to determine the species distribution and antimicrobial susceptibilities of enterococci isolated from clinical samples in a tertiary care hospital of North India. Enterococcus species isolated from blood, urine, pus, sterile fluids and the hospital environment from October 2003 to January 2004 were identified by standard biochemical tests. Antimicrobial susceptibility testing was performed by the disk diffusion method as per NCCLS guidelines. Out of a total of 105 Enterococcus species recovered during the study period, E. faecium (42.90%) and E. faecalis (40.00%) constituted the predominant isolates. Enterococcus faecium was the commonest blood culture isolate while E. faecalis predominated pus and urine samples. Other species isolated were E. mundtii, E dispar, E. durans, E. avium, E. raffinosus and E. gallinarum. High-level aminoglycoside resistance was detected in 73.3% of isolates. Resistance to vancomycin, teicoplanin and linezolid was not detected. Prevalence of a wide variety of Enterococcus species in clinical samples together with their variable antimicrobial susceptibility patterns emphasizes the need for routinely carrying out detailed speciation and in vitro susceptibility testing of enterococcal isolates in the clinical bacteriology laboratory.

Enterococcal bacteraemia in a tertiary care hospital of North India.

A prospective study was conducted to determine clinical and bacteriologic features and antibiotic resistance pattern of enterococci isolated from cases of bacteraemia over a 7-month period. A total of 103 patients were identified during the study period whose blood culture was found to be positive for Enterococcus species. Bacteraemia was nosocomially acquired in 100 patients and community acquired in three. Enterococcus faecalis was isolated in 99 patients and E faecium in four. Bacteraemia was polymicrobial in 34 patients. Majority of patients had serious underlying diseases and were on prior therapy with cephalosporins. A source of bacteraemia was found in 59 patients (57.2%); intravascular catheters being the most common identifiable source. Overall mortality rate was 5.8%. High level aminoglycoside resistance was found in 76 (73.8%) of the enterococcal isolates. Vancomycin resistance was not found in any of the isolates. Bacteraemia due to enterococci is emerging as a significant clinical problem in hospital settings. A watchful vigilance is therefore required as regards their antibiotic resistance pattern particularly high level aminoglycoside resistance and vancomycin resistance. In addition hospital practices like prolonged use of in situ catheters and inadvertent antibiotic usage need to be minimised.

Group C streptococcal bacteremia: a case report from India.

Group C streptococci are a common cause of infection in animals and a rare cause of bacteremia in human beings. The entity is often seen in elderly people with a severe underlying illness. We report here the only case of Group C streptococcal bacteremia reported in our hospital, caused by Streptococcus equisimilis, a beta-hemolytic Group C streptococcus. The patient was a 10-year old male with a known history of aplastic anemia. In spite of specific therapy with penicillin, the outcome was fatal.

Prevalence of Aspergillus species in clinical samples isolated in an Indian tertiary care hospital.

CONTEXT (BACKGROUND): In recent times, it has become important to determine the prevalence of different Aspergillus species in clinical samples in view of difference in antifungal susceptibility noted in some species. AIMS: To determine the species prevalence of Aspergillus isolates in various clinical samples received in the Mycology Laboratory at our institute. METHOD: Over a period of 4-years, a total of 18,731 samples were processed, and species identification carried out by standard microbiological methods. RESULTS: Four hundred and fifty six samples (2.43%) were culture positive for Aspergillus species. A.flavus (46.93%) was the most common isolate, followed by A.fumigatus (37.72%) and A.niger (15.35%). It was observed that A.fumigatus was the predominant species isolated from blood and respiratory specimens, A.flavus was predominantly isolated from nasal polyps whereas A.niger predominated in nail specimens. Culture positivity was highest in the age group 12-65 years and in males. Sixty-nine patients (15.13%) were admitted to the intensive care unit. CONCLUSIONS: The study highlights the diverse manifestations caused by Aspergillus species in human beings and also throws light on the different species prevalent locally. The knowledge would prove useful in selecting empirical antifungal therapy and formulating prophylactic and pre-emptive strategies.