Association between human leukocyte antigen-DRB1 and human leukocyte antigen-DQB1 alleles and pemphigus vulgaris in Indian patients: A case–control study

Background: HLA-DRB1*04, -DRB1*08, -DRB1*14, -DQB1*03 and -DQB1*05 are reported to have significant association with pemphigus vulgaris; however, this is partially dependent on ethnicity. This study was done to determine the HLA-DR and -DQ types prevalent in Indian patients with pemphigus vulgaris. Methods: A prospective case–control study was done for a period of 9 months in Christian Medical College Vellore, India. HLA typing was done by PCR-SSOP method in 50 cases and 50 healthy controls. Allele frequencies in cases and controls were compared and odds ratios with 95% confidence interval were calculated. Results: The mean age of the patients (29 females, 21 males) and that of controls (36 males, 14 females) were 41.3 ± 13.65 and 35.42 ± 11.09 years, respectively. HLA-DRB1*14 was present in 47 patients and 18 controls (OR, 27.85; 95% CI, 7.57–102.42) and HLA-DQB1*05 was seen in 47 patients and 24 controls (OR, 16.97; 95% CI, 4.66–61.80). The haplotype DRB1*14, DQB1*05 was present in 44 patients and 14 controls (OR, 18.86; 95% CI, 6.58–54.05). DRB1*15 was present in 7 cases and 16 controls (OR, 0.35; 95% CI, 0.13–0.94) and DQB1*06 was present in 8 cases and 19 controls (OR, 0.31; 95% CI, 0.12–0.80). HLA-DQB1*03 was associated with significantly higher pemphigus disease area index scores. Limitations: The main limitations were that the numbers studied were small as the study was conducted at a single center, and the haplotype analysis was limited only to the proband. PDAI scores could have been influenced by prior treatment. Conclusion: There was a significant association between HLA-DRB1*14 and HLA-DQB1*05 and pemphigus vulgaris in our patients. A negative association was seen with DRB1*15 and DQB1*06.

Red cell alloimmunization among antenatal women attending a tertiary care hospital in south India.

Red cell alloimmunization among antenatal women attending a tertiary care hospital in south India Jophy Varghese, Mary P. Chacko, Molly Rajaiah & Dolly Daniel Department of Transfusion Medicine & Immunohaematology, Christian Medical College & Hospital, Vellore, India Received December 13, 2011 Background & objectives: Detection of maternal alloimmunization against red cell antigens is vital in the management of haemolytic disease of the foetus and newborn (HDFN). This study was conducted to measure the presence of allosensitization to blood group antibodies in the antenatal women attending a tertiary care hospital and to observe the proportion of minor blood group antibodies to assess the benefit of screening for the same. Methods: All antenatal women registered in the hospital between January 2008 and January 2009, were screened for irregular antibodies using a commercial 3-cell antibody screening panel. Antibody identification was performed on samples found positive using a commercial 11 cell-panel. Results: Screening was performed on 5347 women, 339 (6.34%) of whom were Rh negative. Allosensitization was found in 79 women (1.48%; confidence interval 1.17 -1.84). In 29 of these 79 (37%) women the allo-antibodies could not be identified. In the remaining 50 women, 54 antibodies were characterized. A total of 40 clinically significant antibody specificities were identified among 36 women, of whom four were Rh(D) positive. Allosensitization with clinically significant antibodies was found in 9.43 per cent (confidence interval 6.55-13.06) Rh(D) negative and in 0.08 per cent (confidence interval .02-0.2) Rh(D) positive women. Anti D was the most frequent antibody found in 8.85 per cent Rh(D) negative women. The remaining clinically significant antibodies identified included anti-C, c, E, Jka, Jkb, M and S. In Rh(D) negative women, anti-D and antibodies of the Rh system contributed 83.3 and 94.4 per cent of clinically significant antibodies. However, in Rh(D) positive women, non-Rh antibodies comprised three out of four clinically significant antibodies. Interpretation & conclusions: The presence of alloimmunization in our study corroborated with data reported from India. The most frequent antibody was anti-D. However, a significant fraction was non-D. Alloimmunization among Rh(D) positive women though low as compared to Rh(D) negative women, included clinically significant antibodies, and most of these were non Rh.

Correlation between hepatitis B genotypes, 1896 precore mutation, virus loads and liver dysfunction in an Indian population.

BACKGROUND/OBJECTIVES: Hepatitis B virus (HBV) genotypes may differ in pathogenicity. However, the interplay between different virus characteristics such as genotypes, mutants and virus loads has not been well studied . We investigated the association between HBV genotype, presence of 1896 precore mutation and HBV viral loads in patients with HBV-related liver disease. METHODS: One hundred and sixteen HBV DNA-seropositive patients attending a gastroenterology outpatient clinic and 107 HBV DNA-seropositive blood donors were recruited. The subjects were stratified as those with normal (Group I, n=164) and elevated (Group II, n=59) ALT levels. The HBV genotype and the presence of the 1896 precore mutation were determined, and plasma HBV DNA levels measured. RESULTS: Genotype C was more common in Group II than in Group I (10 (17%) vs. 4 (2.4%); p< 0.005). There was no relationship between the 1896 precore mutation and the HBV DNA levels. Subjects with genotype C (n=14) had higher HBV DNA levels than those with genotypes A (n=33) or D (n=158). CONCLUSIONS: The infecting genotype, but not the presence of 1896 precore mutation, correlates with HBV load. The association of genotype C with higher virus loads and with elevated ALT may point to a greater pathogenicity of this genotype.

A pilot study on the seroprevalence of parvovirus B19 infection.

BACKGROUND & OBJECTIVES: Human parvovirus B 19 (PVB 19) causes aplastic crisis in children with congenital haemolytic anaemia, erythema infectiosum, abortion and stillbirth. Since data on PVB 19 prevalence is lacking in India, a pilot study was undertaken to estimate the prevalence of IgG antibody in children and adults. METHODS: The samples were obtained from children attending our hospital and from volunteer blood donors, majority of whom were from south India. They included 45 children aged 1-5 yr, 39 aged 6-10 yr, 42 aged 11-15 yr and 100 healthy blood donors > 15 yr of age. Sera were tested for the presence of antibody to PVB 19 using a commercial enzyme immuno assay (EIA). RESULTS: Of 226 samples tested, 113 (50%) were positive for PVB 19 IgG. The prevalence of antibody increased from 8.9 per cent at 1-5 yr to 70 per cent in those > 15 yr: the median age of infection was between 6 and 15 yr. Sex and domiciliary status did not have significant effect on the prevalence of antibody. The IgG antibody index increased significantly with age, suggesting repeated exposure to the virus. INTERPRETATION & CONCLUSION: This seroprevalence study indicates that large numbers of individuals show exposure to PVB 19 virus. The exposure as indicated by IgG positivity is seen to increase with age. The IgG negative individuals may be considered to be at risk of developing infections due to PVB 19.