Regional variations in antimicrobial susceptibility of community-acquired uropathogenic Escherichia coli in India: Findings of a multicentric study highlighting the importance of local antibiograms.

Objectives: Evidence-based prescribing is essential to optimize patient outcomes in cystitis. This requires knowledge of local antibiotic resistance rates. Diagnostic and Antimicrobial Stewardship (DASH) to Protect Antibiotics (https://dashuti.com/) is a multicentric mentorship program guiding centers in preparing, analyzing and disseminating local antibiograms to promote antimicrobial stewardship in community urinary tract infection. Here, we mapped the susceptibility profile of Escherichia coli from 22 Indian centers. Methods: These centers spanned 10 Indian states and three union territories. Antibiograms for urinary E. coli from the outpatient departments were collated. Standardization was achieved by regional online training; anomalies were resolved via consultation with study experts. Data were collated and analyzed. Results: Nationally, fosfomycin, with 94% susceptibility (inter-center range 83-97%), and nitrofurantoin, with 85% susceptibility (61-97%), retained the widest activity. The susceptibility rates were lower for co-trimoxazole (49%), fluoroquinolones (31%), and oral cephalosporins (26%). The rates for third- and fourth-generation cephalosporins were 46% and 52%, respectively, with 54% (33-58%) extended-spectrum ß-lactamase prevalence. Piperacillin-tazobactam (81%), amikacin (88%), and meropenem (88%) retained better activity; however, one center in Delhi recorded only 42% meropenem susceptibility. Susceptibility rates were mostly higher in South, West, and Northeast India; centers in the heavily populated Gangetic plains, across north and northwest India, had greater resistance. These findings highlight the importance of local antibiograms in guiding appropriate antimicrobial choices. Conclusions: Fosfomycin and nitrofurantoin are the preferred oral empirical choices for uncomplicated E. coli cystitis in India, although elevated resistance in some areas is concerning. Empiric use of fluoroquinolones and third-generation cephalosporins is discouraged, whereas piperacillin/tazobactam and aminoglycosides remain carbapenem-sparing parenteral agents.

Are we missing the silver lining of COVID-19 pandemic: An analytical study to determine effects of three COVID-19 peaks on antimicrobial susceptibility of Staphylococcus aureus isolates.

Background: Given the evolving nature of COVID-19, for better understanding of its effect on antimicrobial resistance of Staphylococcus aureus (S. aureus), it becomes crucial that we follow the resistance patterns across different surges of COVID-19 cases. Methods: This prospective surveillance study extended over two years from January 2020-March 2022 and was conducted in a healthcare center of North India. Susceptibility patterns of Staphylococcus aureus during January-March 2020 were considered as prepandemic patterns. Processing of clinical specimens, identification of S. aureus, and in-vitro antibiotic susceptibility testing were performed in accordance with standard microbiological testing procedures and Clinical Laboratory Standard Institute guidelines. Results: Lowest prevalence (38.9%) of Methicillinresistant S. aureus was reported during January-March 2021 and July-September 2021. More than 50% S. aureus isolates were susceptible to linezolid, cotrimoxazole, tetracycline, and gentamicin in January-March 2020. In January-March 2021, ≥50% of S. aureus isolates from clinical specimens were additionally susceptible to clindamycin and erythromycin. Antibiotic agents of linezolid, tetracycline, clindamycin, and cotrimoxazole were susceptible in ≥50% of S. aureus isolates in January-March 2022. Conclusions: This study reveals a sharp decline in overall resistance to commonly prescribed antibiotic agents for S. aureus isolates after first peak of COVID-19 cases. However, same trend was not observed in subsequent peaks and probably we are approaching the same resistance levels that were seen prior to COVID-19 pandemic.

Colistin Susceptibility Testing by Colistin Broth Disk Elution MIC Method among Carbapenem-resistant Gram-negative Blood Culture Clinical Isolates in a Tertiary Care Setting, East Delhi, India.

Background: Antibiotic resistance is a growing concern for bloodstream infections (BSIs), especially with the emergence of multidrug-resistant (MDR) gram-negative bacteria. In this study, we aimed to assess the pattern of colistin susceptibility using the colistin broth disc elution (CBDE) method among carbapenem-resistant gram-negative clinical isolates from blood cultures in a high burden tertiary healthcare setting in East Delhi. Methods: A total of 106 carbapenem-resistant gram-negative clinical isolates were tested. The most common isolates were Klebsiella pneumoniae, Escherichia coli, Enterobacter species, and Klebsiella oxytoca by CBDE method. Result: All the carbapenem resistant gram-negative bacterial blood culture isolates showed intermediate colistin susceptibility. This was statistically significant by chi-square test (p<0.5). Conclusion: This study highlights the need to monitor colistin resistance trends in the face of increasing antimicrobial resistance. Accurate surveillance of emerging colistin resistance is crucial for effective management of BSIs caused by carbapenem-resistant gram-negative bacteria.

Amoebal Tubulin Cleavage Late during Infection Is a Characteristic Feature of Mimivirus but Not of Marseillevirus.

Mimivirus and Marseillevirus infections of Acanthamoeba castellanii, like most other viral infections, induce cytopathic effects (CPE). The details of how they bring about CPE and to what extent and how they modify the host cytoskeletal network are unclear. In this study, we compared the rearrangement of the host cytoskeletal network induced by Mimivirus and Marseillevirus upon infection. We show that while both Mimivirus and Marseillevirus infections of A. castellanii cells cause retraction of acanthopodia and depolymerization of the host actin filament network, the Mimivirus infection also results in characteristic cleavage of the host tubulin, a phenomenon not previously reported with any intracellular pathogens. Furthermore, we show that the amoebal tubulin cleavage during Mimivirus infection is a post-replicative event. Because time-lapse microscopy showed that Mimivirus infection leads to the bursting of cells, releasing the virus, we hypothesize that tubulin cleavage together with actin depolymerization during the later stages of Mimivirus assembly is essential for cell lysis due to apoptotic/necrotic cell death. We also characterize the Mimivirus-encoded gp560, a Zn metalloprotease, however, the purified gp560 protein was unable to cleave the commercially available porcine brain tubulin. While protein synthesis is essential for causing the morphological changes in the case of Mimivirus, the proteins which are packaged in the viral capsid along with the genome are sufficient to induce CPE in the case of Marseillevirus. IMPORTANCE In general, intracellular pathogens target the cytoskeletal network to enable their life cycle inside the host. Pathogen-induced changes in the host cell morphology usually accompany global changes in the cytoskeleton resulting in cytopathic effects. While viruses have been shown to use the host actin cytoskeleton for entry and transport during early infection, the role of microtubules in the viral life cycle is only beginning to emerge. Here, we show that the giant viruses Mimivirus and Marseillevirus both induce depolymerization of the actin filament, Mimivirus also causes a characteristic cleavage of tubulin not previously reported for any intracellular pathogen. Because tubulin cleavage occurs late during infection, we hypothesize that tubulin cleavage aids in cell death and lysis rather than establishing infection. The different strategies used by viruses with similar host niches may help them survive in competition.

Vulnerability of financial markets in India: The contagious effect of COVID-19.

This study aims to examine the impact of COVID-19 on financial markets, using emerging market data. Specifically, panel data regression is applied on 3200 observations for daily market returns during lockdown in India. The event study methodology is adopted to show abnormal returns registered in the lockdown period. A contrasting breakdown effect of COVID-19 on various Indian industries has been observed through sectoral analysis. The study also provides empirical evidence for lockdown measures taken by the government on stock market returns and post lockdown impact of COVID-19 on daily market returns for over 6550 observations.

Incidence and Medicolegal Significance of Wormian Bones in Human Skulls in North India Region.

INTRODUCTION: Wormian bones (Wbs) are small bones located in or near the sutures of the skull which are irregular in size, shape, and number. The present study is to look into the morphological details of such supernumerary bones of skull with regards to their incidence, number, and topography in skulls from the Haryana region. MATERIALS AND METHODS: This observational study was carried out in the tertiary care hospital, in the region of Haryana and the total of 147 human skulls were examined during routine autopsy procedures with respect to sutures and topographic distribution of Wbs. The data were statistically analyzed. RESULTS: In the present study, the overall incidence of Wbs was seen in 52 skulls (35.3%) with males having 23.8% and females having 11.5%. CONCLUSION: The knowledge of incidence and distribution of Wbs in the skull could be useful to radiologists, causality medical officers, and autopsy surgeons in successfully differentiating a skull fracture from normal suture with Wbs or exit gunshot wound from fractured small Wb and thus ruling out the possibilities of presence or absence of fractures due to physical abuse, brittle bones, and exit gunshot wounds. It is also helpful to neurosurgeons in timely diagnosis and management of diseases or fractures in relation to the Wbs.

Cartridge-based nucleic acid amplification test: a novel rapid diagnostic tool to study the burden of tuberculosis from a tertiary care hospital.

Despite efforts to limit the morbidity and mortality from tuberculosis (TB), it continues to be an important cause of death. There is an urgent need for a diagnostic test that accurately and quickly diagnoses TB, especially if it is also a near-point-of-care test. The GeneXpert polymerase chain reaction test (known in India as CBNAAT [cartridge-based nucleic acid amplification test] and is capable of diagnosing TB and rifampicin resistance within 2 h) is a promising tool. The duration of our study was two years and was carried out in the DOTS centre of a tertiary care hospital in India. A total of 5449 samples were processed using CBNAAT. Of the total samples tested, 2068 were extra-pulmonary. The following information was collected: number of extra-pulmonary samples processed; number of Mycobacterium tuberculosis (M. tuberculosis)-positive samples; patterns of rifampicin sensitivity; number of people living with HIV (PLHIV); and number of children. Of the samples, 62.1% were from suspected pulmonary TB patients. Out of the total samples tested using CBNAAT, 21.8% were positive for M. tuberculosis. Rifampicin resistance was seen in 9.2%, 8.5% and 10.3% of the total, pulmonary and extra-pulmonary samples, respectively, in M. tuberculosis-positive samples. Overall, 36.9% samples were from the paediatric population and 5.7% belonged to PLHIV. Rifampicin resistance was seen in 8.8% and 8.3% of the M. tuberculosis-positive paediatric and PLHIV samples, respectively.

Evaluation of Treponema pallidum Hemagglutination Assay among Varying Titers of the Venereal Disease Research Laboratory Test.

BACKGROUND AND OBJECTIVE: Syphilis, besides being a significant cause of perinatal morbidity and mortality, is a substantial cause of adult morbidity. A discordant serological result can present a diagnostic challenge; hence, a fundamental knowledge about the diagnostic limitations or interpretation of these assays becomes imperative for the clinicians to avoid management dilemma. The study was proposed to see the usefulness and correlation of Treponema pallidum hemagglutination assay (TPHA) with varying titers of Venereal Disease Research Laboratory (VDRL) test. MATERIALS AND METHODS: Over a period of 2 years, 22,351 sera were subjected to screening for syphilis by VDRL test. TPHA test was performed for confirmation in 243 of the total sera. RESULTS: VDRL reactivity was seen in 0.77% of the tested sera. TPHA positivity was 58.85% among the sera tested. Calculated sensitivity, specificity, positive predictive value, and negative predictive value of VDRL against TPHA were 87.41%, 52%, 72.25%, and 74.29%, respectively. TPHA positivity was found to be 100% and 55% in VDRL reactive cases with titers ≥32 and <8, respectively. CONCLUSION: Screening and diagnostic serological tests for syphilis should be reviewed in routine by the treating physician in the light of clinical presentation and the history of infection and treatment.

Ophthalmic Presentation of Disseminated Tuberculosis with Relapse-Immunological Profile.

TB as the cause of uveitis varies from 0.5 to 10.5%; low sensitivity of confirmatory laboratory investigations and inconsistency of diagnostic criteria leads to paucity of data. Diagnosis requires a high level of suspicion and is often presumptive based on indirect evidences. Interferon gamma, Interleukin-2 and Neopterin are key biomarkers in immuno-regulation of Mycobacterium tuberculosis infection. The relative shift from Interleukin-2 towards Interferon gamma (Interferon gamma/Interleukin-2) is more discriminatory for active tuberculosis. Protein carbonyl and Malondialdehyde, as oxidative stress markers, characterize active tuberculosis. A case of disseminated TB presenting with acute uveitis had a recurrent tubercular lymphadenitis after completing category I treatment under revised national tuberculosis control programme. The present study evaluates the potential utility of above mentioned biomarkers to predict atypical presentation in difficult cases of tuberculosis. Though tuberculous uveitis is amenable to treatment in early course of disease, the delay in diagnosis can have serious consequences for the patient.

Diagnostic Potential of Circulating Biomarkers in Adenosine Deaminase Diagnosed Pleural Tuberculosis Cases.

Pleural tuberculosis accounts for nearly 20% of Extra pulmonary tuberculosis. Adenosine deaminase, commonly used biomarker for the diagnosis, is non specific and there is paucity of literature on its correlation with conventional or newer methods for the diagnosis of extra pulmonary forms of TB. The aim of the study was to assess diagnostic potential of T cell function markers [interferon (IFN-γ), interleukin (IL-2) and IFN-γ/IL-2 ratio]; macrophage activation marker [neopterin]; and oxidative stress markers [protein carbonyl and malondialdehyde (MDA)] in pleural tuberculosis. 26 pleural TB cases diagnosed on the basis of suggestive chest X-ray and raised serum ADA levels and healthy controls were included in the study. Pleural fluid specimens were subjected to Zeihl Neelsen staining and culture on Lowenstein Jensen medium. Serum IFN-γ, IL-2, neopterin and protein carbonyl levels detection were done by ELISA and MDA levels were determined by measuring the thiobarbituric acid reactive substances. Median serum levels of IFN-γ, IL-2, IFN-γ/IL-2 ratio, neopterin, protein carbonyl and MDA were significantly different between cases and controls. Levels of all biomarkers except IL-2 were significantly higher in cases with contact history. Mean levels of ADA and ESR were 46.27 U/L and 46.62 mm/hr in PTB cases. AUC for IFN-γ, IL-2, IFN-γ/IL-2 ratio, neopterin, protein carbonyl and MDA were significantly discriminative for cases and controls. IFN-γ/IL-2 ratio was best discriminatory biomarker with highest area under ROC curve. Though no correlation was seen between ADA and any of the six biomarkers, ESR levels correlated significantly with all biomarkers except IL-2 by spearman's correlation coefficient. Though all the circulating biomarkers under study provide useful supportive evidence for the diagnosis of PTB, further studies involving diverse control groups particularly non-PTB effusion are needed to validate these results.

Comparative Diagnostic Utility of Neopterin and IFN-γ/IL-2 in Extrapulmonary Tuberculosis.

Resurgence of TB has emphasized the need for newer methods of diagnosis. Extrapulmonary tuberculosis (EPTB), being paucibacillary, is a diagnostic dilemma. The aim of the present study was to correlate IFN-γ/IL-2 with neopterin in diagnosis of EPTB. Extrapulmonary specimens from 69 clinically diagnosed cases were stained by Ziehl-Neelsen and cultured on Lowenstein-Jensen medium for Mycobacterium tuberculosis. ELISA was used to assess serum IFN-γ, IL-2 and neopterin levels. Median serum levels of IFN-γ/IL-2 and neopterin were 3.22 and 21.6 nmol/L in clinically diagnosed EPTB cases and 0.52 and 4.20 nmol/L in healthy controls respectively (p < 0.001). Both IFN-γ/IL-2 and neopterin were significantly higher in culture positive (14.64 and 49.8 nmol/L) than culture negative cases (3.01 and 17.5 nmol/L) respectively (p < 0.05). IFN-γ/IL-2 was significantly higher in AFB smear positive cases (8.63) than smear negative cases (3.04) (p = 0.003), whereas no significant difference in neopterin levels was seen (p = 0.307). A positive correlation between IFN-γ/IL-2 and neopterin was seen in EPTB cases (spearman's rho = 0.453, p < 0.001), whereas in healthy controls no such correlation existed (spearman's rho = 0.018, p = 0.884). An urgent need for research in the field of biomarkers exists to utilize them as point of care test in the diagnosis of EPTB.

Neopterin and oxidative stress markers in the diagnosis of extrapulmonary tuberculosis.

BACKGROUND: Extrapulmonary tuberculosis (EPTB) often presents with nonspecific signs and symptoms. Further the paucibacillary nature of extrapulmonary specimens and irregular distribution of bacilli lower the sensitivity of conventional diagnostic methods making EPTB, a diagnostic dilemma. OBJECTIVE: To study neopterin, protein carbonyl and malondialdehyde (MDA) in EPTB. METHODS: Sixty nine clinically confirmed cases with an equal number of age and sex matched healthy controls were enrolled. Ziehl-Neelsen staining for acid fast bacilli and culture on Lowenstein-Jensen medium were performed on all the extrapulmonary specimens. Serum neopterin and protein carbonyl levels were estimated using commercial ELISA kits. Malondialdehyde was determined by measuring thiobarbituric acid reactive substances. RESULTS: Serum neopterin, protein carbonyl and MDA levels were significantly discriminative for cases of EPTB from healthy controls (p < 0.05). Levels of all the three biomarkers under study significantly differed between culture as well as smear positive and negative cases. A positive correlation between neopterin and protein carbonyl was seen among the cases. CONCLUSIONS: So far few studies have integrated combination of validated host biomarkers for active disease in EPTB. Our study suggests the potential diagnostic role of neopterin, protein carbonyl and MDA in EPTB.

Lactobacillus rhamnosus GG antagonizes Giardia intestinalis induced oxidative stress and intestinal disaccharidases: an experimental study.

The present study describes the in vivo modulatory potential of Lactobacillus rhamnosus GG (LGG), an effective probiotic, in Giardia intestinalis-infected BALB/c mice. Experimentally, it was observed that oral administration of lactobacilli prior or simultaneous with Giardia trophozoites to mice, efficiently (p < 0.05) reduced both the severity and duration of giardiasis. More specifically, probiotics fed, Giardia-infected mice, showed a significant increase in the levels of antioxidants [reduced glutathione (GSH) and superoxide dismutase (SOD)] and intestinal disaccharidases [sucrase and lactase] and decreased levels of oxidants in the small intestine, in comparison with Giardia-infected mice. Histopathological findings also revealed almost normal cellular morphology of the small intestine in probiotic-fed Giardia-infected mice compared with fused enterocytes, villous atrophy and increased infiltration of lymphocytes in Giardia-infected mice. The results of the present study has shed new light on the anti-oxidative properties of LGG in Giardia mediated tissue injury, thereby suggesting that the effects of probiotic LGG are biologically plausible and could be used as an alternative microbial interference therapy.

Probiotic Lactobacillus rhamnosus GG modulates the mucosal immune response in Giardia intestinalis-infected BALB/c mice.

BACKGROUND: Gut homeostasis can be altered by the oral administration of health-promoting microorganisms, namely probiotics that are known to reinforce the host immune response. AIM: The aim of this study was to elucidate the immunomodulatory effect of orally administered probiotic Lactobacillus rhamnosus GG (LGG) in Giardia-infected mice. METHODS: BALB/c mice were fed orally with probiotic LGG either 7 days prior to or simultaneously with the challenge dose of Giardia trophozoites. The administration of the probiotic was continued for 25 days, and immunomodulatory potentials in terms of secretory immunoglobulin A (IgA) levels, CD8+ and CD4+ T lymphocytes, and expression of pro-inflammatory [tumor necrosis factor-alpha, interferon-gamma (INF-γ)] and anti-inflammatory cytokines [interleukin (IL)-4, IL-6, IL-10] were studied. RESULTS: Oral feeding of LGG prior to or simultaneously with the test dose of Giardia seems to have modulated both arms (humoral and cellular) of the mucosal immune system since a significant increase in the levels of specific secretory IgA antibody, IgA+ cells, and CD4+ T lymphocytes were observed in contrast with the decreased percentage of cytotoxic CD8+ T lymphocytes. The stimulated mucosal immune response in probiotic fed Giardia-infected mice was further correlated with the enhanced levels of anti-inflammatory cytokines IL-6 and IL-10 and reduced levels of pro-inflammatory cytokine INF-γ. CONCLUSIONS: This is the first study to show that oral administration of the effective probiotic LGG to Giardia infected mice could be used as a bacterio-therapy that restores the normal gut microflora and modulates the mucosal immune response.

Lactobacillus rhamnosus GG as an Effective Probiotic for Murine Giardiasis.

The gut microflora is an important constituent in the intestinal mucosal barrier and has been introduced as the concept of probiotic therapy that beneficially affects the host by improving its intestinal microbial balance. Therefore, the main objective of the study was to explore the protective potential of various lactobacilli strains for murine giardiasis. By experimentation, it was found that the probiotic supplementation of either Lactobacillus casei, L. acidophilus, L. plantarum, or L. rhamnosus GG, 7 days prior to inoculation with G. lamblia trophozoites, reduced the rate of cyst excretion compared with Giardia-infected mice. Interestingly, L. GG was found to be the most effective probiotic in reducing the duration of giardia cycle and acts as an effective prophylactic probiotic for murine giardiasis but needs to be clinically correlated due to entirely different human microflora.

A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles.

BACKGROUND: The synthesis of gold nanoparticles (GNPs) has received considerable attention with their potential applications in various life sciences related applications. Recently, there has been tremendous excitement in the study of nanoparticles synthesis by using some natural biological system, which has led to the development of various biomimetic approaches for the growth of advanced nanomaterials. In the present study, we have demonstrated the synthesis of gold nanoparticles by a novel bacterial strain isolated from a site near the famous gold mines in India. A promising mechanism for the biosynthesis of GNPs by this strain and their stabilization via charge capping was investigated. RESULTS: A bacterial isolate capable of gold nanoparticle synthesis was isolated and identified as a novel strain of Stenotrophomonas malophilia (AuRed02) based on its morphology and an analysis of its 16S rDNA gene sequence. After 8 hrs of incubation, monodisperse preparation of gold nanoparticles was obtained. Gold nanoparticles were characterized and found to be of ~40 nm size. Electrophoresis, Zeta potential and FTIR measurements confirmed that the particles are capped with negatively charged phosphate groups from NADP rendering them stable in aqueous medium. CONCLUSION: The process of synthesis of well-dispersed nanoparticles using a novel microorganism isolated from the gold enriched soil sample has been reported in this study, leading to the development of an easy bioprocess for synthesis of GNPs. This is the first study in which an extensive characterization of the indigenous bacterium isolated from the actual gold enriched soil was conducted. Promising mechanism for the biosynthesis of GNPs by the strain and their stabilization via charge capping is suggested, which involves an NADPH-dependent reductase enzyme that reduces Au3+ to Au0 through electron shuttle enzymatic metal reduction process.

Retraction: A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles.

[This retracts the article on p. 39 in vol. 8, PMID: 19619318.].