Distribution of MecA and Erm Genes among Methicillin-resistant Staphylococcus Aureus with Inducible Resistance to Clindamycin.

BACKGROUND: The emergence of Methicillin-resistant Staphylococcus aureus and its ability to confer cross-resistance to macrolide-lincosamide-streptogramin B has complicated the treatment against it. Gene-based studies among phenotypic methicillin-resistant isolates with inducible resistance to clindamycin are less available in Nepal. This work was undertaken to detect the mecA and erm genes among such phenotypes isolated from clinical samples. METHODS: S. aureus isolated from different clinical samples was identified by standard microbiological procedures (Gram-staining, colony morphology, and different biochemical tests). Methicillin-resistant and inducible resistant to clindamycin phenotypes were detected by using cefoxitin disc (30 µg) and a double disk diffusion test according to the Clinical and Laboratory Standards Institute guidelines and mecA and erm genes were detected by polymerase chain reaction. RESULTS: Among 120 S. aureus isolates, 51.67% (n=62) were MRSA, and the prevalence of inducibly-resistant, constitutively-resistant and Macrolide-Streptogramin phenotypes were 15.83% (n=19), 28.33% (n=34) and 15.83% (n=19) respectively. While 35.84% (n=43) of isolates showed sensitivity to both antibiotics, erythromycin and clindamycin. Out of 14 inducibly-resistant phenotypes, 57.14% (n=8) were found carrying ermC and 28.57% (n=4) phenotypes contained both ermA and ermC. All phenotypes were positive for the mecA gene. CONCLUSIONS: Macrolides-Lincosamide-Streptogramin B resistance was predominant among methicillin-resistant S. aureus. While all isolates with inducible clindamycin resistance harbored mecA gene, most of them also harbored ermC gene. The higher prevalence of inducible-resistant to clindamycin indicated the need for rational use of antimicrobial agents.

Hand and nasal carriage of Staphylococcus aureus and its rate of recolonization among healthcare workers of a tertiary care hospital in Nepal.

Background: Carriers of Staphylococcus aureus among healthcare workers (HCWs) can spread the bacteria to patients and the environment, in addition to their own risk of infection. Objectives: To determine the prevalence of S. aureus carriers among HCWs and the rate of recolonization after decolonization therapy with mupirocin. Methods: Nasal and hand swabs from HCWs of a tertiary care hospital in Nepal were cultured on mannitol salt agar and S. aureus isolated were identified using standard microbiological procedures. Detection of MRSA and mupirocin-resistant S. aureus (MupRSA) isolates were done phenotypically. Identified S. aureus carriers were decolonized with 2% mupirocin nasal ointment. Recolonization of the carriers was assessed monthly for the next 5 months. Results: Among the 213 HCWs, 18.3% were S. aureus carriers (35 nasal carriers, 4 both nasal and hand carriers, and no hand carriers). Overall, 9.4% of the HCWS were MRSA carriers and none were MupRSA carriers. After decolonization, 25.6% of them were recolonized and 50.0% of the recolonization was detected after 3 months of decolonization. All recolonized carriers had only MSSA strains (which colonized only nose), and none were recolonized with MupRSA. Conclusions: HCWs are frequent carriers of S. aureus and MRSA. Due to their continuous exposure to the hospital environment, they are at risk of colonization by this MDR organism. Regular screening and decolonization of HCWs working with high risk, vulnerable patients would reduce the risk of MRSA transmission from HCWs to patients.

Antimicrobial Resistance in Typhoidal Salmonella in Nepal: Surveillance for Enteric Fever, 2016-2019.

BACKGROUND: Enteric fever (caused by Salmonella enterica) has been associated with poor hygiene and is endemic in the South-Asian countries. The increase in resistance to first line antimicrobials has been observed, while the emergence of multi/extremely drug resistance cases have been identified in several countries. The objective of this study is to analyze the current trend of antimicrobial resistance in Salmonella isolates in Nepal, and to identify the status of multi- and extremely- drug resistant isolates. METHODS: We recruited individuals at study hospitals with suspected enteric fever between September 2016 and August 2019 and performed blood cultures. The Salmonella isolates were tested for antimicrobial susceptibility and the antimicrobial resistance trend was evaluated. RESULTS: 1438 positive blood culture isolates were studied for antimicrobial resistance. 88% were culture positive for Salmonella Typhi and 12% for Salmonella Paratyphi. Multidrug resistant S. Typhi cases appeared mostly in December 2018 and January 2019, while there were no multidrug resistant S. Paratyphi cases. Also, extremely drug resistant S. Typhi cases were not observed during the study period. CONCLUSIONS: The Salmonella isolates were mostly susceptible to first-line antimicrobials, cephalosporins and others. Many fluoroquinolones non-susceptible Salmonella were obtained, nevertheless their overall trend seems to be declining. In addition, the S. Paratyphi total cases are reducing since September 2017. Among S. Typhi isolates, only few were multidrug resistant and there were no extremely drug resistant isolates.

A hospital based surveillance of metallo-beta-lactamase producing gram negative bacteria in Nepal by imipenem-EDTA disk method.

BACKGROUND: A rising threat of the rapid spread of acquired metallo-beta-lactamases (MBLs) among major Gram-negative pathogens is a matter of public health concern worldwide. Hence, for a low income nation like Nepal, surveillance data on MBL producing clinical isolates via a cost effective technique is necessary to prevent their dissemination as well as formulation and regulation of antimicrobial stewardship policy. METHODS: The prospective study was conducted at Nepal Medical College, Kathmandu from May to October, 2014 to assess the prevalence of MBL production among ceftazidime-resistant Gram-negative rods (GNRs) isolates. The samples were processed according to standard microbiological procedure following the Manual of clinical Microbiology. Isolated GNRs were subjected to susceptibility testing against the selected panel of antibiotics by Kirby- Bauer disc diffusion method and interpretation made in conformity with the Clinical and Laboratory Standards Institute (CLSI) guidelines. Ceftazidime-resistant isolates were subjected to the detection of MBL production by imipenem-EDTA combined disc (CD) method. RESULTS: Among the Gram-negative isolates, 5.80% (21/362) were found to be MBL positive with Acinetobacter spp. showing the highest prevalence i.e. 85.71% (18/21), followed by P. aeruginosa i.e. 14.29% (3/21). None of the other cefazidime resistant gram negative bacteria tested were found to be positive for MBL production with all the positive isolates determined to be Multidrug resistant (MDR) strains. CONCLUSION: This study demonstrated a higher rate of resistance among P. aeruginosa and Acinetobacter spp. to a wide variety of antibiotic categories with an additional burden of MBL production within them, warranting a need for strict surveillance and rapid detection of MBL production among the GNRs.

Frequency of Blood Culture Isolates and their Antibiogram in a Teaching hospital.

INTRODUCTION: Bloodstream infections are associated with significant patient morbidity and mortality. Antimicrobial susceptibility patterns should guide the choice of empiric antimicrobial regimens for patients with bacteremia. METHODS: Blood sample received from the patient attending Nepal Medical College and Teaching Hospital from March, 2012 - August, 2012 were subjected to culture. Isolate identification and antimicrobial susceptibility testing was done by standard microbiological method. RESULTS: Out of the total 2,766 blood samples, 368 (13.3%) showed bacterial growth. The percentage of neonatal septicemia was 368 (13.3%). Staphylococcus aureus (28%) was the most common isolates followed by Salmonella enterica Serotype Typhi (22%), Coagulase negative Staphylococci (9.5%), Salmonella enterica Serotype Paratyphi ((7.6%) and Klebsiella pneumoniae (7.6%). 26.3% of the isolates of Staphylococcus aureus were oxacillin resistant. Most of the gram positive organisms were susceptible to amikacin and vancomycin and showed high level resistance to cefuroxime and cotrimoxazole. Out of 109 isolates of typhoid bacilli, 95.3% were resistant to nalidixic acid,79% to ciprofloxacin and 60.5% to ofloxacin. More than 50% of the isolates of Klebsiella pneumoniae and Escherichia coli showed resistance to cephalosporins and cotrimoxazole. Acinetobacter sp. showed high resistance (more than 60%) to ceftriaxone and ofloxacin. More than 20% of the isolates of Pseudomonas aeruginosa were resistant to ciprofloxacin and amikacin. CONCLUSIONS: Ongoing surveillance for antimicrobial susceptibility remains essential, and will enhance efforts to identify resistance and attempt to limit its spread.

Effect of urogenital cleaning with paper soap on bacterial contamination rate while collecting midstream urine specimens.

CONTEXT: Urinary tract infection (UTI) is one of the major health problems. Urine culture is considered as a gold standard method for the diagnosis of UTI. But, improper sample collection can lead to contamination with normal urogenital flora. Use of any portable disinfectant that can reduce contamination rate would be the significant help in urine culture interpretation. AIMS: To observe the effect of urogenital cleaning with paper soap on bacterial contamination rate while collecting specimens. MATERIALS AND METHODS: A cross-sectional comparative study was done in 600 patients aged 15-45 years, equally divided into three groups. The first group was given sterile container and instructed to collect midstream clean catch urine (MSU) after urogenital cleaning with provided piece of paper soap. The second group was given sterile container and strictly instructed to collect the MSU sample after urogenital cleansing by tap water only. The third group was given the sterile container and asked for midstream urine. Collected specimens were inoculated in CLED media, incubated aerobically for overnight at 37°C. Reporting of culture was done according to the guideline of American Society of Microbiology. RESULTS: The contamination rate in the three groups were 6.0%, 13.0%, and 27.5%, respectively (P value < 0.05), which was statistically significant. CONCLUSIONS: Contamination rate was significantly lower in group who provided urine specimen after urogenital cleaning with paper soap. Thus, cleaning the urogenital area may reduce the need of the repeat sample to rule out actual contamination and prevent from the unnecessary antibiotic treatment.

Prevalence of cryptosporidium species in paediatric patients in Eastern Nepal.

Cryptosporidium species have been implicated as an important cause of childhood diarrhoea. We determined the prevalence of cryptosporidiosis in HIV seronegative children 15 years of age and below presenting with diarrhoea in the BP Koirala Institute of Health Sciences, Nepal. Faeces were collected over a 12-month period. Coccidian oocysts were detected using modified acid-fast staining. Intestinal parasites were found in 9.15% of diarrhoeal stool. Coccidian parasites were observed in 4.4% (with 4.1% cryptosporidium and two cyclospora). Coccidia were the most recurrent parasite found in this study. The detection was throughout the year with clustering during the rainy season.

Intestinal parasitosis in school going children of Dharan municipality, Nepal.

This community-based investigation was carried out to estimate the prevalence of intestinal parasitosis in primary school-going children of the Dharan municipality, Sunsari, Nepal from 2007 through 2008. A total of 182 stool samples were collected from 101 male and 81 female children of ages 4 to 10 years. A questionnaire including the factors predisposing to parasitosis, was filled up by the parents of each child. Parasitic examination was carried out by direct wet mount examination and concentration method using 10% formol-ether. The prevalence rate was found to be 22.5%. The result revealed preponderance of Giardia lamblia (11.5%) followed by Entamoeba histolytica/dispar (4.4%), Ascaris lumbricoides (3.3%), hookworm (1.6%) and Enterobius vermicularis (0.5%). Statistically significant difference in the prevalence with respect to age and gender was not seen. However, socioeconomic status, type of toilet used and the practice of hand washing had a strong correlation (p < 0.05) with the prevalence of parasitic infection. Abdominal discomfort also had a strong statistical association (p < 0.05) with the prevalence of parasitic infection. Proportionally higher infection rate was seen in participants not using filtered or boiled water. Lack of education of mothers and children, improper toilets and failure to practice proper hand washing were perceived from this study as contributors to the acquisition of intestinal parasitic infections.

Profile of bacterial isolates from suspected cases of infective endocarditis (IE): a retrospective study in a north Indian tertiary care hospital.

Infective Endocarditis (IE) is an emerging infection of the twenty-first century. This chronic Infection is mainly caused by bacteria, although fungi can also be associated with it. It is Important to know the profile of bacteria causing IE in a given region so as to suggest the empirical therapy for this serious illness. Blood culture isolates of clinically diagnosed or suspected cases of IE admitted to various wards of the All India Institute of Medical Sciences were analyzed retrospectively from January 2000 to June 2004. Standard techniques were used for the isolation and identification of the bacteria. Our study has demonstrated the predominance of Gram-negative bacilli, especially, Acinetobacter species and Pseudomonas aeruginosa, which are notorious for antimicrobial resistance, as the aetiological agents of IE. Amongst Gram-positive cocci, Enterococci exhibiting HLAR comprised the predominant species. Methicillin resistance among staphylococcal strains in this Tertiary care hospital is adding to the therapeutic challenge in the management of this serious illness. Although antimicrobial treatment should not be delayed in such cases, we cannot undermine the importance of isolation and identification of the etiological agents and the determination of the antimicrobial susceptibility for the management of these life-threatening conditions as well as for the formulation of guidelines for empirical therapy of these cases.

Lymphocyte immunophenotype reference ranges in healthy Indian adults: implications for management of HIV/AIDS in India.

With the advent and application of standard and sensitive flow cytometry methods, it became essential to establish reference intervals in healthy individuals to demarcate between health and disease. A reference range of lymphocyte populations for normal individuals is important in the diagnosis and prognosis of immunodeficiency diseases like AIDS. We tried to accomplish this by studying the values for T lymphocyte subsets for 200 healthy North Indian adults between 18 and 55 years. We obtained the following reference ranges for various T lymphocyte subsets: CD4 count (304-1864 cells/microl with the median of 666 cells/microl), CD4% (17.5-50.6% with the median of 35%), CD8% (14-53% with the median of 32.3%), CD3% (43-89% with the median of 70.5%), and CD4/CD8 ratio (0.04-3.5 with the median of 1.04). Significant variations were observed for normal reference intervals for T lymphocyte subsets according to the race, ethnic origin, age group, and gender.