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Introduction Hepatitis B virus (HBV) infection is an endemic in many Asian countries, and among the major routes of transmission, transfusion is the one that should be prevented. Occult HBV infection (OBI) is defined as the presence of HBV DNA in the absence of detectable HBsAg, with or without anti-HBV antibodies. The aim of this study was to detect the prevalence of anti-HBc total antibodies among the HB surface antigen (HBsAg) negative individuals by way of enzyme-linked immunosorbent assay (ELISA), and detect the presence of HBV DNA among the anti-HBc seropositives by polymerase chain reaction (PCR). Anti-HBs among the HBV DNA positives were also found out by enzyme-linked fluorescent assay (ELFA). Materials and Methods A total of 910 serum samples was subjected to initial screening for HBsAg by MERILISA HBsAg ELISA kits. The anti-HB core (HBc) total antibody titer was evaluated using MONOLISA ELISA (Biorad) kits. If found negative, the samples were discarded. If found positive, the samples underwent HBV DNA testing by nested PCR. Antibody to hepatitis B surface antigen (anti-HBs) was calculated among the DNA positives by ELFA. Results A total of 133 samples were positive for anti-HBC total antibody, resulting in an overall prevalence of 14.6%. Overall prevalence of HBV DNA among the anti-HBc seropositives was 2.2%. Conclusion Among the three HBV DNA positive patients, two belonged to the preoperative screening group, which is an alarming situation. Screening of blood for HBsAg has reduced the incidence of posttransfusion hepatitis, but HBV still remains the major source of transfusion transmitted infection in India.
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BACKGROUND AND OBJECTIVES: Resistance to methicillin in methicillin resistant strains of Staphylococcus aureus (MRSA) is due to the presence of mec-A gene, which encodes a low affinity penicillin binding protein (PBP)-2a or PBP2. Accurate and rapid identification of MRSA in clinical specimens is essential for timely decision on effective treatment. The aim of the study was to compare three different methods for detection of MRSA namely cefoxitin disc diffusion, CHROM agar MRSA and VITEK-2 susceptibility with PCR which is the gold standard reference method and to find the antibiotic susceptibility pattern of these isolates by VITEK-2. MATERIALS AND METHODS: A Total of 100 non-duplicate S. aureus isolates were collected from different clinical samples among both outpatient and inpatients. Detection of MRSA among these isolates was done by cefoxitin disc diffusion, VITEK-2, CHROM agar MRSA and PCR. RESULTS: The sensitivity and specificity of cefoxitin disc diffusion and Vitek was found to be 97.2% and 100%, while that of CHROM agar was found to be 100% and 78.6%. The overall prevalence of MRSA in our study by PCR was 72%. CONCLUSION: Based on the findings in our study, isolates which show cefoxitin zone diameter < 22 mm can be reported as MRSA. However, those isolates which have a zone diameter between 22-24 mm, should ideally be confirmed by PCR.
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BACKGROUND AND OBJECTIVES: Hepatitis C is the most common hepatotropic viral infection that affects patients on maintenance hemodialysis. Most of the laboratories in India depend on HCV antibody detection by ELISA. PCR based studies on detection of HCV RNA among haemodialysis patients are very scanty in India. The current study was undertaken to find the prevalence of HCV among haemodialysis patients by ELISA and PCR. MATERIALS AND METHODS: This prospective study was conducted from January to May 2018 in a total of 100 samples. Patients more than 18 years of age, who had undergone at least 15 sessions of dialysis were enrolled in the study. All samples were screened for HCV antibody by ELISA and HCV RNA by PCR. Data regarding age and gender of the patients, history of blood transfusion, duration of hemodialysis, total bilirubin levels were collected from medical records. RESULTS: Among the 100 samples, only one was positive for HCV antibody by ELISA. Eight samples were positive for HCV RNA by PCR. In this study 62.5% of the HCV positives had a previous history of blood transfusion. Duration of dialysis was more among the HCV positive group but there was no statistical significance. CONCLUSION: This is the first study from the southern state of Kerala in India showing the prevalence of HCV among hemodialysis patients by PCR. Our study showed an overall HCV prevalence of 8% by PCR. All the PCR positive samples were negative by 3rd generation ELISA which is an alarming finding and further justifies the need for PCR for detecting HCV.
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BACKGROUND AND OBJECTIVES: Shigellosis is one of the most common causes of morbidity and mortality in children in developing countries. To the best of our knowledge, there is no published data in the study area on the antimicrobial susceptibility pattern and prevalence of Shigella species among diarrheagenic cases. Therefore, a retrospective analysis was done to find the Shigella serotypes, common age group affected, and antimicrobial resistance pattern of Shigella isolates in South Kerala. METHODS: Stool samples collected from cases of dysentery and diarrhea from January 2011 to December 2016 were processed. Standard bacteriological methods were used to isolate, identify, and determine the antimicrobial susceptibility pattern of Shigella isolates. The data were analyzed using SPSS version 16. RESULTS: Among 1585 stool samples, 48(3%) yielded Shigella. The most common serogroup isolated was Shigella sonnei (62.5%) followed by Shigella flexneri. Of 48 isolates, 44(91.6%) isolates were found to be multidrug resistant. Over the 5-year period, the isolates show 100% resistance to nalidixic acid, ciprofloxacin, and cotrimoxazole. Eight isolates were found to be resistant to ceftriaxone and cefotaxime. The presence of Extended spectrum betalactamase (ESBL) was phenotypically confirmed in five isolates. CONCLUSION: Even though S. flexneri is the most common Shigella-causing diarrhea, S. sonnei was found to be the most important species responsible in our study. Multidrug resistance was common (91.6%) and the most common multidrug resistance profile was ampicillin-nalidixic acid-cotrimoxazole-ciprofloxacin. Regular monitoring of antibiotic susceptibility pattern including detection of beta lactamases should be done in all microbiology laboratories. Guidelines for therapy should be monitored and modified based on regional susceptibility reports.