The prevalence and clinical significance of irregular antibodies other than ABO in Rh negative pregnant women in tertiary care hospital

Introduction: Routine pre transfusion testing consists of ABO and Rh typing, antibody screening and compatibility testing. The purpose of the antibody screen is to detect red blood cell antibodies other than Anti-A or Anti-B. These antibodies are called ‘unexpected’ because only 0.3 to 2% of the general population have positive antibody screen. Objective: This study was undertaken to know the prevalence of irregular antibodies in Rh negative pregnant women and also to analyse the clinical significance of these antibodies in the form of neonatal outcome. Materials and method: A Prospective study was conducted on the study population from September 2011 to Feuary 2013. During this period all the antenatal cases reporting in the department of Obstetrics and Gynaecology, Safdarjung hospital, New Delhi were typed for ABO and D antigen. Out of these antenatal cases 500 Rh negative pregnant women were included in the study and were screened for red blood cell alloantibodies by performing Indirect Coomb’s test(ICT). The specificity of the antibody was identified by further testing of those samples that gave positive reaction on initial screening.All these Rh negative antenatal cases were followed up and their neonates were examined for the evidence of hemolysis in the form of anaemia, jaundice, splenomegaly. Results: This study noted the prevalence of irregular red cell antibodies in 4.2% of pregnant women. Anti-D is the most common Antibody identified. accounting for 66.7%. Anti-C and anti-D together accounted for 23.9%. Anti-Kell and Anti-Jkb were identified in 0.4%. Incidence of neonatal anemia is significantly higher in babies born to mothers with RBC antibodies. Conclusion: The prevalence of irregular Red Cell Antibodies in Rh negative women is 4.2%.

Emergence of pandemic 2009 influenza A H1N1, India.

Background & objectives: Pandemic H1N1 caused deluge of cases from 74 countries and prompted World Health Organization to raise warning to phase 6. The present study was conducted on throat and nasal swab samples received and tested at National Centre for Disease Control, Delhi, India during 2009-2010 to collect epidemiological and clinical information on positive cases. Methods: Throat and nasopharyngeal swabs from category C influenza A H1N1 patients during May 2009-September 2010 along with their clinico-epidemiological details were collected from identified hospitals from Delhi and other States. Samples were tested by Real time reverse transcriptase PCR using primers and probes developed at CDC, Atlanta for four influenza target genes. Results: A total of 33,751 samples, both throat and nasal swab samples from each patient were tested for H1N1 influenza virus, of which, 7943 (23.5%) were positive for pandemic influenza A H1N1 and 3759 (11.1%) were positive for influenza A (seasonal flu). Maximum number of positive cases (N=2792, 35.1%) were from 20-39 yr age group, comprising 1790 (22.5%) males and 1182 (14.8%) females. Only 2620 (33%) positive cases were close contact of influenza A H1N1 positive patient. Majority cases presented (N=2792, 35.1%) with fever 7005 (88.1%), followed by 6133 cases (77.2%) exhibiting fever and cough, 377 (4.7%) complained of fever, cough, nasal catarrh and 362 (4.5%) cases had fever with shortness of breath. Interpretation & conclusions: The study showed a peak of cases of pandemic influenza A H1N1 in December 2009 and indicated predominance of H1N1 positive cases among 20-39 yr age group and among males compared to females.

Development of TaqMan real-time polymerase chain reaction for the detection of the newly emerging form of carbapenem resistance gene in clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii.

Purpose: The newly emerging form of the so-called New Delhi Metallo-beta-lactamases (NDM-1) has been reported recently from patients worldwide and broadly thought as a potential source for the major global health problem. Thus, it is important to study the epidemiology of the so-called NDM-1 harbouring bacteria to prevent its further spread and to place effective control measures. The present study describes the use of the real-time polymerase chain reaction (PCR) assay for the detection of the bla NDM-1 gene using TaqMan probes among clinical isolates. Materials and Methods: Clinical isolates of Escherichia coli (11 strains), Klebsiella pneumoniae (17 strains) and Acinetobacter baumannii (six strains) that were resistant to either of the carbapenems (meropenem or imipenem) were included in the study. The presence of carbapenemases in such strains was confirmed using the modified Hodge test. A real-time PCR assay was optimized for the detection of NDM-1 using a cloned synthetic gene fragment followed by testing of the clinical isolates. The findings were further confirmed using PCR and gene sequencing. Results: TaqMan probe assay displayed a good detection limit with analytical sensitivity of the assay up to 10 copies of bla NDM-1 gene per reaction. The isolates of E. coli and K. pneumoniae revealed narrow range crossing point values (Cp values) between (12-17) cycles (mean Cp value 14), indicating number of bla NDM-1 gene copies of 106-108. The wider range of Cp values (15-34) cycles with a higher mean Cp value (23.6) was observed in A. baumannii with number of bla NDM-1 gene copies of 103-108. Conclusions: The study demonstrates that real-time PCR assay based on TaqMan chemistry is a useful technique for the detection of bla NDM-1 harbouring clinical isolates of E. coli, K. pneumoniae and A. baumannii. The assay has great precision in measuring the number of bla NDM-1 gene copies per specimen of DNA.

Pandemic Influenza A (H1N1) 2009 in India: Duration of virus shedding in patients under antiviral treatment.

Background: National Centre for Disease Control (NCDC), Delhi, is a national nodal centre for surveillance of pandemic Influenza A (H1N1) in India. The present study was undertaken to see the period of infectivity in positive cases undergoing antiviral therapy. Objective: To assess the duration of virus shedding by real-time polymerase chain reaction (real-time PCR) in some of the positive patients taking Oseltamivir treatment. Materials and Methods: Clinical samples (throat swabs, nasal swabs and nasopharyngeal swabs) collected by the clinicians from patients quarantined in government hospitals in different parts of India are being sent to the designated reference laboratory at Delhi for screening presence of pandemic Influenza virus. The samples are tested by Real-Time PCR using CDC recommended reagents and protocol for confirmation of the H1N1 novel influenza virus. In 150 of the positive cases, we requested the clinicians to send samples for 5 consecutive days after administration of antiviral therapy, to see the trend of therapy response on viral shedding. Samples for more than 5 days were received from patients till they showed no amplification for any of the three target genes (Influenza A, Swine Influenza A or Swine H1). Results and Conclusion: In 99.33% (149/150) cases, the influenza infection resolved within 10 days. Sixty-four percent (96/150) of the positive patients turned negative within 5 days of the start of antiviral treatment. Only one patient belonging to high risk group showed prolonged virus shedding (19 days).

Histone as future drug target for malaria.

Malaria continues to be a major cause of mortality and morbidity in tropical countries and affecting around 100 countries of the world. As per WHO estimates, 300-500 million are being infected and 1-3 million deaths annually due to malaria. With the emerging knowledge about genome sequence of all the three counterparts involved in the disease of malaria, the parasite Plasmodium, vector Anopheles and host Homo sapien have helped the scientists to understand interactions between them. Simultaneous advancement in technology further improves the prospects to discover new targets for vaccines and drugs. Though the malaria vaccine is still far away in this situation there is need to develop a potent and affordable drug(s). Histones are the key protein of chromatin and play an important role in DNA packaging, replication and gene expression. They also show frequent post-translation modifications. The specific combinations of these posttranslational modifications are thought to alter chromatin structure by forming epigenetic bar codes that specify either transient or heritable patterns of genome function. Chromatin regulators and upstream pathways are therefore seen as promising targets for development of therapeutic drugs.

Relationship of Xba1 and EcoR1 polymorphisms of apolipoprotein-B gene to dyslipidemia and obesity in Asian Indians in North India.

BACKGROUND: Genetic investigation of dyslipidemia and obesity prevalent in the Indian population form the basis of this study. METHODS AND RESULTS: The frequency of restriction fragment length polymorphisms (Xba1 and EcoR1) of the apolipoprotein-B gene was investigated in a case-control study of 30 hyperlipidemic and 40 normolipidemic subjects. By univariate analysis, old age, higher body mass index, waist-hip ratio and sum of four skinfolds were found to be significantly associated with hyperlipidemia. The frequencies of X- and E+ alleles of the apolipoprotein-B gene were significantly higher in North Indians in the state of New Delhi (0.83 and 0.91, respectively) as compared to the observations made in Caucasians in previous studies, but was similar to the frequency reported in Indians settled in Singapore and the UK. There were no significant differences in the allele or genotype frequencies of either Xba1 or EcoR1 polymorphisms between the hyperlipidemic and normolipidemic groups. On multiple logistic regression analysis considering body mass index, waist-hip ratio, percentage body fat and genotypes as independent variables, no association was observed between the apolipoprotein-B genotypes and serum lipid components. Further, there were no associations between apolipoprotein-B polymorphisms and generalized obesity (as assessed by body mass index, sum of four skinfolds, and percentage total body fat) and abdominal obesity (as measured by waist circumference and waist-hip ratio). CONCLUSIONS: We conclude that apolipoprotein-B (Xba1 and EcoR1) polymorphisms do not appear to influence serum lipid levels and parameters of generalized andregional obesity in the study sample.