Molecular characterization of hepatitis A virus strains in a tertiary care health set up in north western India.

Background & objectives: Hepatitis A virus usually causes acute viral hepatitis (AVH) in the paediatric age group with a recent shift in age distribution and disease manifestations like acute liver failure (ALF). This has been attributed to mutations in 5’non-translated region (5’NTR) which affects the viral multiplication. The present study was aimed to carry out the molecular detection and phylogenetic analysis of hepatitis A virus strains circulating in north western India. Methods: Serum samples from in patients and those attending out patient department of pediatric gastroenterology in a tertiary care hospital in north India during 2007-2011 with clinically suspected AVH were tested for anti-hepatitis A virus (HAV) IgM antibodies. Acute phase serum samples were subjected to nested PCR targeting the 5’NTR region followed by sequencing of the representative strains. Results: A total of 1334 samples were tested, 290 (21.7%) were positive for anti-HAV IgM antibody. Of these, 78 serum samples (< 7 days old) were subjected to PCR and 47.4% (37/78) samples showed the presence of HAV RNA. Children < 15 yr of age accounted for majority (94%) of cases with highest seropositivity during rainy season. Sequencing of 15 representative strains was carried out and the circulating genotype was found to be III A. The nucleotide sequences showed high homology among the strains with a variation ranging from 0.1-1 per cent over the years. An important substitution of G to A at 324 position was shown by both AVH and ALF strains. The cumulative substitution in AVH strains Vs ALF strains as compared to GBM, Indian and prototype strain in the 200-500 region of 5’ NTR was comparable. Interpretation & conclusion: Our results showed hepatitis A still a disease of children with III A as a circulating genotype in this region. The mutations at 5’NTR region warrant further analysis as these affect the structure of internal ribosomal entry site which is important for viral replication.

Role of reverse transcriptase polymerase chain reaction for the diagnosis of human rabies.

Background & objectives: Traditionally, rabies diagnosis is made by demonstration of rabies viral antigen by direct immunofluorescence (DIF) and mouse inoculation test (MIT). The present study was carried out to evaluate the role of reverse transcriptase-polymerase chain reaction (RT-PCR) in comparison with these conventional techniques for the diagnosis of rabies. Methods: Skin biopsies, corneal impression smears and saliva sample were collected ante-mortem and brain tissue and CSF were collected post-mortem from ten clinically suspected rabies patients. DIF, Seller staining, MIT and RT-PCR were performed on the patients’ samples for the diagnosis of rabies. The ability of RT-PCR to detect rabies virus earlier as compared to other assays was tested both for reference virus as well as clinical isolates. Results: All samples taken ante-mortem were negative for DIF test. Six of 10 post-mortem brain tissues of the clinically suspected patients were positive both by RT-PCR and MIT, of these six, five were positive by DIF test and four were positive by Seller stain. RT-PCR could detect the rabies virus earlier as compared to DIF, both from clinical isolates and fixed rabies virus. Interpretation & conclusions: The present results showed 100 per cent sensitivity and specificity of RT-PCR as compared to 83.3 per cent of DIF and 66.7 per cent of Sellers stain for diagnosis of rabies. RT-PCR also detected rabies viral infection earlier as compared to conventional tests and can also be used on ante-mortem samples. Thus, the present study shows the usefulness of RT-PCR as an alternative to MIT for the confirmation of rabies diagnosis.

Viral markers in patients with hemophagocytosis: A prospective study in a tertiary care hospital.

Background : Hemophagocytic syndrome (HPS) is a rare clinicopathological condition characterized by the activation of macrophages with prominent hemophagocytosis in bone marrow and other reticulo-endothelial systems. HPS can be familial or secondary to infections including viruses. Aim : To study the viral markers in patients with HPS. Materials and Methods : Serum samples of patients with HPS and control group were screened for anti EBV VCA IgM, and IgG, anti-Parvo B19 IgM, and anti-CMV IgM antibodies using commercially available ELISA kits and CMV and ParvoB19 DNA by polymerase chain reaction (PCR). Results and Discussion : The present prospective study reports the profile of viral markers in HPS cases from north India. Among the 14 HPS cases 43% (6/14) were positive for at least one viral marker tested, of which EBV was found to be the most prevalent (3/6: 50%) followed by parvovirus B19(2/6: 33%) and cytomegalovirus (1/6: 17%). Mortality was noted in 33% of virus associated HPS patients. Our study highlights the higher association of Epstein-Barr virus (EBV) with HPS as compared to other viruses along with higher rate of mortality in both parvovirus B 19 and EBV associated HPS.

Epidemiologic lessons: Chickenpox outbreak investigation in a rural community around Chandigarh, North India.

Purpose: Primary infection with Varicella Zoster virus (VZV) leads to Varicella or chickenpox. The epidemiology of Varicella has changed dramatically since the introduction of the Varicella vaccine in 1995. The routine childhood immunization in a few countries in the western world like Germany and the United States has reduced the incidence of the disease, associated complications, hospital admissions and deaths related to its complications. However, chickenpox outbreaks are common in naive unvaccinated communities in India. Materials and Methods: We report an outbreak of chickenpox that occurred in a village situated on the outskirts of Chandigarh city in North India in the winter of 2007. The outbreak was confirmed by the detection of VZV IgM by enzyme-linked immunosorbent assay (ELISA) on serum samples from the patients. In patients showing active lesions, Giemsa and indirect immunofluorescence was carried out on scrapings from vesicular lesions. Results: A total of 162 cases occurred in the present outbreak. The serum samples were collected from 20 patients, and all of them showed positive serology for VZV IgM antibodies while 19 showed a positive VZV IgG result by ELISA. The scrapings were collected from two patients showing active lesions, and both were positive by the Tzanck smear examination, and VZV antigen could be demonstrated by immunofluorescence. Conclusions: There is an urgent need to identify naive communities and unvaccinated individuals at risk. Also, there is a need for regular training programmes of health workers posted in peripheral centers so that highly contagious communicable diseases can be picked up in time and such outbreaks can be prevented.

Congenital rubella and cytomegalovirus infections in and around Chandigarh.

AIMS: This study has analyzed the role of rubella and cytomegalovirus (CMV) in infections of children and pregnant women. SETTINGS AND DESIGN: The study was carried out in a tertiary care hospital. Data from blood samples from pregnant women (asymptomatic and also women with obstetric problems) and children (suspected of intrauterine infections) that were received in the laboratory over a period of 8 years were analysed. MATERIALS AND METHODS: The samples were tested for rubella- and CMV-specific IgM antibodies by capture enzyme linked immunosorbent assay. RESULTS: In children, the overall positivity for rubella- and CMV-specific IgM antibodies was 2.8% and 12.5%, respectively. In asymptomatic pregnant females, rubella positivity was 0.7% while in women with obstetric complications it was 3.4%. IgM antibody positivity in cases of CMV was 7.8% in both asymptomatic pregnant women and also in women with obstetric complications. CONCLUSIONS: The study indicated that infection with CMV is more common than the rubella virus. The incidence of rubella has reduced over the past few years. Hence, screening for rubella infection may be reserved for women with obstetric complications only. The routine screening for CMV among all antenatal cases is a debatable issue.

Herpetic meibomianitis: an unusual case report.

Herpes simplex virus (HSV) infection of the eye can vary from mild blepharitis to sight threatening choreoretinitis. Primary infection of the eye is usually sub-clinical but reactivation of a latent infection can lead to recurrent disease. Although, herpetic blepharitis is a well documented entity, this virus has so far not been incriminated in the causation of meibomianitis, an inflammatory condition of the meibomian gland. This paper reports a case of meibomianitis due to Herpes simplex virus.

Otosclerosis--do we have a viral aetiology?

The etiology of otosclerosis remains an enigma though there are evidences suggesting a viral involvement. This study aimed to find out the relationship between viral infections and otosclerosis. Twenty two patients with otosclerosis and 10 healthy controls were included in the study. IgM antibodies to varicella zoster virus (VZV), measles, rubella, human cytomegalovirus (HCMV) and herpes simplex virus (HSV) were detected using micro ELISA. Paul Bunnel Davidsohn test was performed to rule out Ebstein Barr virus (EBV) infection. Overall, 5(22.7%) patients showed antibodies to one or more viruses. IgM antibodies against measles and VZV could be demonstrated in 4(18.1%) and 1(4.5%) patients respectively. None of the samples were found to be positive for HSV, HCMV, rubella and EBV antibodies. Controls were negative for all the viruses tested. The difference in seropositivity between the patient and control group was not statistically significant (p>0.05). Thus, this study suggests that otosclerosis is not commonly associated with a systemic viral infection.

Acute liver failure and severe hemophagocytosis secondary to parvovirus B19 infection.

Parvovirus infection presenting as severe hemophagocytosis is extremely rare. We report a 13-year-old girl with acute parvovirus infection who had severe hemophagocytosis resulting in severe pancytopenia and hepatic failure.