Whole genome sequence-based molecular characterization of blood isolates of carbapenem-resistant Enterobacter cloacae complex from ICU patients in Kolkata, India, during 2017-2022: emergence of phylogenetically heterogeneous Enterobacter hormaechei subsp. xiangfangensis.

Blood-borne infections caused by the carbapenem-resistant Enterobacter cloacae complex (CR-ECC) are major public threats with respect to the challenges encountered during treatment. This study describes the whole genome sequencing-based molecular characteristics of blood isolates (n = 70) of CR-ECC from patients admitted to the intensive care unit of tertiary care hospitals in Kolkata, India, during 2017-2022 with respect to species identification, antimicrobial resistance (AMR) profiling, mechanism of drug resistance, and molecular subtypes. Vitek2 MALDI and species-specific PCR identified Enterobacter hormaechei subsp. xiangfangensis (47.14%) as the emerging CR-ECC subspecies in Kolkata. The predominating carbapenemase and extended-spectrum ß-lactamase genes found were blaNDM-1 (51.42%) and blaCTX-M-15 (27%), respectively. Besides, blaNDM-4, blaNDM-5, blaNDM-7, blaCMH-3, blaSFO-1, blaOXA-181, blaOXA-232, blaKPC-3, and blaDHA-7 genes were also detected, which were not previously reported from India. A multitude of Class 1 integrons (including In180, In4874, In4887, and In4888, which were novel) and plasmid replicon types (IncFIB, IncFII, IncX3, IncHI1-HI2, IncC, and IncR) involved in AMR dissemination were identified. Reverse transcription-PCR and western blot revealed that carbapenem resistance in non-carbapenemase-producing CR-ECC isolates was contributed by elevated levels of ampC, overexpression of acrAB, and loss of ompF. A total of 30 distinct sequence types (STs) were ascertained by multi-locus sequence typing; of which, ST2011, ST2018, ST2055, ST2721, and ST2722 were novel STs. Pulsed-field gel electrophoresis analysis showed heterogeneity (69 pulsotypes with a similarity coefficient of 48.40%) among the circulating isolates, suggesting multiple reservoirs of infections in humans. Phylogenetically and genetically diverse CR-ECC with multiple AMR mechanisms mandates close monitoring of nosocomial infections caused by these isolates to forestall the transmission and dissemination of AMR.IMPORTANCEThe emergence and extensive dissemination of the carbapenem-resistant Enterobacter cloacae complex (CR-ECC) have positioned it as a critical nosocomial global pathogen. The dearth of a comprehensive molecular study pertaining to CR-ECC necessitated this study, which is the first of its kind from India. Characterization of blood isolates of CR-ECC over the last 6 years revealed Enterobacter hormaechei subsp. xiangfangensis as the most prevalent subsp., exhibiting resistance to almost all antibiotics currently in use and harboring diverse transmissible carbapenemase genes. Besides the predominating blaNDM-1 and blaCTX-M-15, we document diverse carbapenemase and AmpC genes, such as blaNDM-4, blaNDM-7, blaOXA-181, blaOXA-232, blaKPC-3, blaCMH-3, blaSFO-1, and blaDHA-7, in CR-ECC, which were not previously reported from India. Furthermore, novel integrons and sequence types were identified. Our findings emphasize the need for strengthened vigilance for molecular epidemiological surveillance of CR-ECC due to the presence of epidemic clones with a phylogenetically diverse and wide array of antimicrobial resistance genes in vulnerable populations.

Current Trends in Antimicrobial Resistance Patterns in Bacterial Pathogens among Adult and Pediatric Patients in the Intensive Care Unit in a Tertiary Care Hospital in Kolkata, India.

Nosocomial infections by multidrug-resistant (MDR) bacteria are among the main causes of morbidity and death in patients hospitalized in intensive care units (ICUs) worldwide. Antibiotic resistance has become a major concern for treating the patients with nosocomial infections. The aim of this study was to describe the antibiotic resistance patterns of pathogens causing infections in adult and pediatric patients in the ICUs of a tertiary care hospital in Kolkata, India. A cross-sectional, retrospective study was conducted from January 2022 to October 2022 on a total of 139 adult and 146 pediatric patients. Depending on clinical symptoms of the patients, samples were collected and subjected to antibiotic sensitivity testing. The culture and sensitivity pattern of clinical isolates from blood, urine, sputum, endotracheal tube (ET) aspirate, and central line catheter insertion site swabs were analyzed. A total of 695 and 556 specimens were obtained from adult and pediatric ICU, respectively. Culture positivity rate among adults and pediatric patients were 37% and 40%, respectively. The most commonly isolated organisms were Gram-negative Enterobacterales and non-fermenters. Most of the bacterial isolates showed very high resistance against multiple antibiotics. Escherichia coli from adult and pediatricpatients were found to be resistant to second generation cephalosporins (95% and 96%, respectively), beta-lactams (95% and 63%, respectively), fluoroquinolones (95% and 81%, respectively), and cotrimoxazole (85% and 78%, respectively). Klebsiella spp. from adult patients were found to be resistant to aminoglycosides (75%), second generation cephalosporins (100%), beta-lactams (94%), fluoroquinolones (92%), carbapenems (88%), and cotrimoxazole (83%). Proteus spp., Acinetobacter baumannii, and Pseudomonas spp. werefound to be resistant to multiple antibiotics. Enterococcus spp. from ICUs showed more than 90% resistance against ampicillin and more than 75% resistance against fluoroquinolones. MDR bacterial infections are increasing in both adult and pediatric ICUs, leading to significant therapeutic challenges. A frequent study of antimicrobial resistance patterns is imperative for antibiotic stewardshipin combatting the deadly effect of the MDR bacteria in critically ill patients.

Microbiological Profile in Patients Having Keratitis in a Tertiary Care Hospital in India.

Background Corneal ulcer or keratitis is defined as a loss of corneal epithelium with underlying stromal infiltration and suppuration associated with signs of inflammation. Corneal blindness is a significant public health problem worldwide; infectious keratitis is one of the predominant preventable causes of blindness. Several studies have evaluated microbial infectious keratitis's etiology, management, and outcome. However, there are regional variations in corneal ulcers' prevalence, risk factors, and outcome. The objective of this study was to isolate and identify the bacterial, fungal, viral, and protozoal etiological organisms causing infectious corneal ulcers along with their prevalence and antimicrobial sensitivity pattern. Methods A prospective observational study was done in the Department of Microbiology and RIO, Medical College & Hospital, Kolkata, for a period of 1 year (February 2019 to January 2020) after obtaining clearance from the Institutional Ethics Committee. Informed consent, demographic data, history of disease onset, duration of symptoms, associated co-morbidities, etc., were taken from the patients fulfilling the inclusion criteria. Corneal scraping samples were collected sterilely to detect bacterial, fungal, parasitic, and viral isolates and identified by standard laboratory procedures. Results A total of 80 patients were included in the study. The risk factors included foreign body in 24 (30%), blunt trauma in 10 (12.5%), steroid use in 8 (10%), contact lens user 4 (5%), and spontaneous in 34 (42.5%). Among these 80 patients, 18 showed growth of bacteria, including Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, and Pseudomonas aeruginosa; four had growth of fungi, including Aspergillus spp. and Fusarium spp, and two were positive for Herpes simplex virus by IFA. Conclusion Early diagnosis and prompt keratitis treatment are critical for preventing visual loss. The identification of the various causative agents of keratitis is essential for the proper management of the cases.

Epidemiology and Antifungal Susceptibility of Candida Species causing Blood Stream Infections: An Eastern India Perspective.

INTRODUCTION: Candidemia is the fourth common cause of blood stream infection worldwide leading to increased mortality and morbidity. A paradigm shift of Candida albicans to Non-albicans candida (NAC) had led to the increase in resistance to empirically used antifungals. So, an epidemiological study and antifungal susceptibility is essential for meticulous use of antifungals. AIMS AND OBJECTIVES: To find out the prevalence and antifungal susceptibility of Candida species causing candidemia. METHODS: automated blood culture done in BACTEC system followed by its identification and susceptibility testing in VITEK-2 system. RESULTS: Non-albicans candida was isolated from 73% cases of candidemia. The commonest isolate among neonates and adults were C.krusei and C.tropicalis respectively. C.haemulonii was significantly high among adult population while C.krusei was significantly high among the neonates. 10.4% NAC isolates were resistant to amphotericin B, flucytosine resistance among 37% NAC isolates and among 44% C.albicans isolates, fluconazole resistance was found among 13% and 15% of NAC and C. albicans respectively. Echinocandins were comparatively sensitive to the candida spp.

Isolated splenic abscess due to melioidosis in type 1 diabetes mellitus: laboratory diagnosis of Burkholderia pseudomallei in resource-restricted setting.

Diabetes mellitus, type 1 in particular, is a well-recognised risk factor for melioidosis, a disease caused by Burkholderia pseudomallei Melioidosis is endemic in Southeast Asia and in northern Australia and has a variety of clinical presentation, isolated splenic abscess being one of them. B. pseudomallei, however, is an uncommon aetiology of splenic abscess. The diagnosis of melioidosis is often overlooked unless the clinician and the microbiologist are suspicious of the condition. Multiple splenic abscesses and perisplenic collection were noted in CT scan of the abdomen in a patient of type 1 diabetes, presenting with fever for preceding 4 weeks. B. pseudomallei was isolated from the splenic aspirate and the diagnosis was made based on gram stain and routine biochemical tests. He was successfully treated with antibiotics. We postulate that the likely route of infection was inoculation through skin, the integrity of which was compromised by multiple subcutaneous insulin injections.

Analysis of blood stream infections, antibiograms and clinical outcomes in haematological patients with febrile neutropenia: data from a tertiary care haematology institute in India.

Timely administration of appropriate empirical antibiotics in febrile neutropenia is crucial for favourable patient outcomes. There are guidelines in place recommending such antibiotics. However, regional variations and local epidemiological data must be evaluated to tailor the antibiotics for best possible and rational use. In this study, we audited the clinical and microbiological data of febrile neutropenic episodes occurring at a tertiary care haematology institution. Three hundred and ninety-three febrile neutropenic episodes occurring in 123 patients over a 1-year period were analysed for microbial profile, sensitivity and resistance patterns, and finally clinical outcomes. Gram-negative bacilli (GNB) blood stream infections (46.9%) were more prevalent as compared to gram-positive infections (41.9%). Overall mortality due to complicated neutropenic sepsis was 19.5% (24/123 patients). Increased resistance to carbapenems, beta-lactam beta-lactamase inhibitor combinations, aminoglycosides, fluoroquinolones, and cephalosporins were observed. Cefepime and tigecycline resistance were seen in 20% and 15% GNB isolates, respectively. Chest was the most frequent focus of infection, and acute myeloid leukaemia (AML) was the most common underlying disorder which correlated with the likelihood of death (p < 0.01). Multidrug-resistant GNB (esp. Klebsiella sp.) are still most worrisome isolates in neutropenic patients. Single-agent cefepime or piperacillin-tazobactam/tigecycline combination may be considered empirical agents. Chest infections and AML were independent predictors of poor clinical outcome in neutropenic patients. Regular audit of infections and antibiotic susceptibility data is needed to improve clinical outcomes in patients with febrile neutropenia.

Accuracy of Quick Sequential Organ Failure Assessment Score to Predict Sepsis Mortality in 121 Studies Including 1,716,017 Individuals: A Systematic Review and Meta-Analysis.

We performed a meta-analysis to assess whether the newly introduced quick Sequential Organ Failure Assessment score could predict sepsis outcomes and compared its performance to systematic inflammatory response syndrome, the previously widely used screening criteria for sepsis. DATA SOURCES: We searched multiple electronic databases including MEDLINE, the Cochrane Library, Embase, Web of Science, and Google Scholar (up to March 1, 2019) that evaluated quick Sequential Organ Failure Assessment score, systemic inflammatory response syndrome, or both (International Prospective Register of Systematic Reviews [PROSPERO]: CRD42018103327). STUDY SELECTION: Studies were included if the outcome was mortality, organ dysfunction, admission to ICU, ventilatory support, or prolonged ICU stay and if prediction performance was reported as either area under the curve, odds ratio, sensitivity, or specificity. DATA EXTRACTION: The criterion validity of the quick Sequential Organ Failure Assessment score and systemic inflammatory response syndrome criteria were assessed by measuring its predictive validity for primary (mortality) and secondary outcomes in pooled metrics as mentioned. The data were analyzed using random effects model, and heterogeneity was explored using prespecified subgroups analyses. DATA SYNTHESIS: We screened 1,340 studies, of which 121 studies (including data for 1,716,017 individuals) were analyzed. For mortality prediction, the pooled area under the curve was higher for quick Sequential Organ Failure Assessment score (0.702; 95% CI, 0.685-0.718; I 2 = 99.41%; p < 0.001) than for systemic inflammatory response syndrome (0.607; 95% CI, 0.589-0.624; I 2 = 96.49%; p < 0.001). Quick Sequential Organ Failure Assessment score consistently outperformed systemic inflammatory response syndrome across all subgroup analyses (area under the curve of quick Sequential Organ Failure Assessment vs. area under the curve of systemic inflammatory response syndrome p < 0.001), including patient populations (emergency department vs ICU), study design (retrospective vs prospective), and countries (developed vs resource-limited). Quick Sequential Organ Failure Assessment score was more specific (specificity, 74.58%; 95% CI, 73.55-75.61%) than systemic inflammatory response syndrome (specificity, 35.24%; 95% CI, 22.80-47.69%) but less sensitive (56.39%; 95% CI, 50.52-62.27%) than systemic inflammatory response syndrome (78.84%; 95% CI, 74.48-83.19%). CONCLUSIONS: Overall, quick Sequential Organ Failure Assessment score outperforms systemic inflammatory response syndrome in predicting sepsis outcome, but quick Sequential Organ Failure Assessment score has relative strengths/weaknesses (more specific but less sensitive) compared with systemic inflammatory response syndrome.

Mitochondrial dysfunction in peripheral blood mononuclear cells in early experimental and clinical acute pancreatitis.

BACKGROUND/OBJECTIVES: Mitochondrial dysfunction occurs in vital organs in experimental acute pancreatitis (AP) and may play an important role in determining severity of AP. However, obtaining vital organ biopsies to measure mitochondrial function (MtF) in patients with AP poses considerable risk of harm. Being able to measure MtF from peripheral blood will bypass this problem. Furthermore, whether mitochondrial dysfunction is detectable in peripheral blood in mild AP is unknown. Therefore, the objective was to evaluate peripheral blood MtF in experimental and clinical AP. METHOD: Mitochondrial respiration was measured using high resolution oxygraphy in an experimental study in caerulein induced AP and in a separate study, in patients with mild AP. Superoxide, cytochrome c, mitochondrial membrane potential (ΔΨ) and adenine triphosphate (ATP) were also measured as other markers of MtF. RESULTS: Even though some states of mitochondrial respiration were increased in both experimental and clinical AP, this did not lead to an increase in net ATP in patients with AP. The increased leak respiration in both studies was further proof of dyscoupled mitochondria. In the clinical study there were also features of mitochondrial dysfunction with increased leak flux control ratio, superoxide, ΔΨ and decreased cytochrome c. CONCLUSION: There is evidence of mitochondrial dysfunction with dyscoupled mitochondria, increased superoxide and decreased cytochrome c in patients with mild acute pancreatitis. Further studies should now determine whether mitochondrial function alters with severity in AP and whether mitochondrial dysfunction responds to treatments.

MicroRNAs in mesenteric lymph and plasma during acute pancreatitis.

OBJECTIVE: To isolate microRNAs (miRNAs) from mesenteric lymph (ML) and peripheral blood and identify those that change with experimental acute pancreatitis (AP). To assess identified AP-associated miRNAs in patient plasma to evaluate them as clinical biomarkers of AP. BACKGROUND: miRNAs, small non-protein-coding molecules that regulate gene expression, are present in many biological fluids. They are increasingly interesting as biomarkers of disease and as novel signaling molecules in pathogenesis. METHODS: Affymetrix miRNA profiling was performed on ML collected from 3 groups of rats with either mild or moderate taurocholate-induced AP and sham controls. Quantitative reverse transcription-polymerase chain reaction was used to validate selected miRNAs in matched rat lymph and plasma and then measured in patients with mild or moderate AP and in healthy volunteers. RESULTS: Eighty-five miRNAs were detectable in rat ML, and many were abundant in all animals irrespective of the presence of AP. Seven miRNAs, comprising miR-375, -217, -148a, -216a, -122, -214, and -138, were increased in ML from rats with AP (P < 0.01). Their abundance also altered with disease severity. miRNAs miR-217, -375, -122, and -148a were also increased in matched rat plasma samples by quantitative reverse transcription-polymerase chain reaction. In the clinical studies, plasma miR-216a was significantly increased in both mild and moderate AP. CONCLUSIONS: This study is the first to demonstrate both the presence of circulating miRNAs in lymph and the alteration of specific miRNAs in AP. Furthermore, these miRNAs alter in rat and human AP plasma and have potential to be explored as novel biomarkers of pancreatitis.

Organ failure and infection of pancreatic necrosis as determinants of mortality in patients with acute pancreatitis.

BACKGROUND & AIMS: There is no consistency between the individual studies in the literature on whether organ failure (OF) or infected pancreatic necrosis (IPN) is the main determinant of severity in acute pancreatitis. We aimed to statistically aggregate the available data and determine the pooled influence of OF and IPN on mortality in patients with acute pancreatitis. METHODS: The search for relevant observational studies was undertaken in the MEDLINE, EMBASE, and Scopus electronic databases, as well as in the proceedings of major gastroenterology meetings. The summary estimates are presented as relative risk (RR) and 95% confidence interval (CI). RESULTS: Fourteen studies comprising 1478 patients with acute pancreatitis were meta-analyzed. A total of 600 patients developed OF and 179 of them died (mortality, 30%); 314 patients developed IPN and 102 of them died (mortality, 32%). In a stratified analysis, patients with OF and IPN had a significantly higher risk of death in comparison with patients with OF and no IPN (RR = 1.94; 95% CI: 1.32-2.85; P = .0007) and in comparison with patients with IPN and no OF (RR = 2.65; 95% CI: 1.30-5.40; P = .0007). CONCLUSIONS: In patients with acute pancreatitis, the absolute influence of OF and IPN on mortality is comparable and thus the presence of either indicates severe disease. The relative risk of mortality doubles when OF and IPN are both present and indicates extremely severe disease or critical acute pancreatitis.