Establishment of T-lymphocyte subset reference intervals in a healthy adult population in Chennai, India.

Estimation of CD4+ T-lymphocytes continues to be an important aspect for monitoring HIV disease progression and response to antiretroviral therapy. Most of the diagnostic laboratories often rely on western text books for CD4+ T-lymphocyte reference values, which could, often be unreliable for usage in local settings. Therefore, we attempted to establish the reference values for T-lymphocyte subsets among healthy adults in a cross-sectional study carried out at the YRG Centre for AIDS Research and Education (YRG CARE) in Chennai, south India, in 213 (84 female and 129 male) healthy, HIV-1/2 seronegative adults as volunteers. Whole blood specimens were processed for CD4+, CD8+ T-lymphocyte estimation and haematological parameters. The established range of CD4+ T-lymphocyte counts for men and women were 383-1347 cells/microl (mean 865 and median 845 cells/microl) and 448-1593 cells/microl (mean 1021 and median 954 cells/microl), respectively. Women had significantly higher absolute CD4+ Tlymphocyte counts (P<0.001) and CD4+:CD8+ T-lymphocyte ratio as compared to men. The established normal range of CD4+ T-lymphocyte % was 21-59 (mean 40.2 and median 40.1). The influence of age was not observed in any of the parameters except CD4+/CD8+ T-lymphocyte ratio with the >45 yr age group. Further studies with greater sample size may be required to define the staging of HIV disease in relation to the normal CD4 T-lymphocyte count in the general population.

Diagnostic utility of serologic markers for genital chlamydial infection in STD patients in Chennai, India.

OBJECTIVES: To evaluate the diagnostic utility of serological markers for C. trachomatis in different clinical groups of STD patients. METHODS: Blood and genital swab specimens were collected from symptomatic STD patients (n=143) attending the STD out patient clinic at the Institute of STDs, Government General hospital, Chennai who enrolled for the study. Serological determination for IgM, IgA and IgG antibodies to C. trachomatis was done using commercial kits. PCR analysis was performed on genital swab samples by using plasmid and major outer membrane protein (MOMP) based primers and patients who were positive by both PCR assays were considered as proven cases of C. trachomatis infection. The serological marker positivity was analysed with PCR positivity. RESULTS: Serologic positivity by IgM, IgA and IgG was 22.4%, 28.7% and 58.7% respectively. The PCR analysis showed 44 (30.8%) cases with confirmed C. trachomatis infection. Seropositivity for IgM (34.1% (15/44) vs. 17.2% (17/99); P<0.05) as well as for IgA (40.9% (18/44) vs. 23.2% (23/99); P<0.05) significantly correlated to PCR positivity, while significant correlation was not seen with IgG positivity. The overall seropositivity (IgM/IgA/IgG) in the study population was 68.5%. CONCLUSIONS: The observations of the present study indicate a high exposure rate to chlamydial infection in STD clinic patients in India. The study also suggests the usefulness of serology instead of PCR to trace chlamydial etiology, especially in deep-seated upper genital tract diseases and to facilitate better clinical management as there was good correlation between serology and PCR positivity.

HIV-1 western blot assay: What determines an indeterminate status?

BACKGROUND: The Western blot assay is the gold standard for the detection of antibodies to human immunodeficiency virus type 1 (HIV-1). However, indeterminate Western blot reactivity to HIV-1 proteins may occur in individuals, who may not be infected with HIV. AIM: This retrospective study was aimed to determine the diagnostic value of the interpretation criteria in relation to commercial kits for HIV-1 diagnosis. METHODS AND MATERIALS: A total of 556 serum/plasma specimens collected from high-risk population attending our HIV clinic from 2000-2004 were tested by three different western blot kits: NEW LAV BLOT I (n=244), HIV BLOT 2.2; (n=112), Genetic Systems HIV-1 (n=237). And the results of western blot strips were analyzed using the various interpretation criteria: WHO/NACO, CDC/ ASTPHLD, ARC, FDA, CRSS and JHU. Some specimens were run on more than one kit. RT-PCR assay was performed on 5 specimens, which were indeterminate with LAV BLOT I. RESULTS: The discrepancy in LAV BLOT I positive results were between 157(64)-176(72), and indeterminate results were between 44(18) to 63(25). No such variations were observed in genetic systems. There are some HIV negative (by PCR) specimens were indeterminate in LAV BLOT I revealing the kit more sensitive and less effective for diagnostic purpose. CONCLUSION: The genetic systems kit is superior to other kits we analyzed and its results are concordant with HIV-1 PCR results. To report, the choice of western blot commercial kit is paramount important than the use of particular interpretation criteria for the diagnosis of HIV-1.

Community prevalence of hepatitis B infection and modes of transmission in Tamil Nadu, India.

BACKGROUND AND OBJECTIVE: There have been very few community based studies on prevalence of hepatitis B virus (HBV) infection in India. We undertook this study to determine the prevalence of HBV infection in a southern State of India, Tamil Nadu and to describe the important factors related to transmission of the virus in the community. METHODS: Analysis of stored blood samples from a representative population of Tamil Nadu from an earlier community cluster survey on sexually transmitted diseases (STD) prevalence using proportionate to population size (PPS) technique was done. Serum markers of HBV viz., hapatitis B surface antigen (HBsAg), hepatitis B e antigen (HBe Ag) and antibody to surface antigen (anti-HBs) were performed. RESULTS: 1981 subjects were screened in the study. HBsAg prevalence was 5.7 per cent (CI 4.6- 6.8) with 23.5 per cent (25/106) of these having positive HBe-antigen. Community seroprevalence (HbsAg + anti-HBs) of hepatitis B infection was 27.4 per cent (CI: 25.3-29.5) with the highest prevalence of 32.7 per cent (CI: 30.2-35.2) noted in the 15-20 yr age group. Significant independent association (OR 1.4; P=0.006) was detected with family history of exposure to HBV infection by logistic modeling. Other risk factors noted to have significant association were use of disposable needles during injection (OR 0.5; P=0.02) in men, smoking (OR 3; P=0.04) and use of condom (OR 0.6; P=0.08) in women. INTERPRETATION AND CONCLUSION: This community based study shows a high prevalence of hepatitis B infection in the state of Tamil Nadu with the highest prevalence being in the younger (15-20 yr) age group. High prevalence rate in childhood with e-antigenemia seen in 23.5 per cent of HBsAg positive subjects suggest childhood transmission. Poor injection practices and high-risk sexual behavior were found to be additional risk factors for transmission of the disease in the community.

Genital chlamydial infection in STD patients: its relation to HIV infection.

In the present report, we have analysed C.trachomatis infection and HIV positivity among patients (n-143) who attended the STD clinic at the Institute of STDs, Government General Hospital, Chennai. HIV positivity rate was significantly high among those with chlamydial infection than in those without chlamydial infection (29.5% (13/44) vs. 11.1% (11/99); p<0.05). The results of the present study suggest the association between C.trachomatis and HIV infections and reinforce the need for routine screening for C.trachomatis as a necessary intervention to reduce the burden of chlamydial diseases and to reduce the risk of HIV and its spread in India.

Evaluation of immunogenicity and safety of Genevac B: A new recombinant hepatitis b vaccine in comparison with Engerix B and Shanvac B in healthy adults.

PURPOSE: Genevac B, a new indigenous recombinant hepatitis B vaccine was evaluated for its immunogenicity and safety in comparison with Engerix B (Smithkline Beecham Biologicals, Belgium) and Shanvac B (Shantha Biotechnics, India) in healthy adult volunteers. METHODS: While 240 study subjects were included in the Genevac B group, 80 each were the subjects for Engerix B and Shanvac B. A three dose regimen of 0,1,2 months was adopted with 20 gm dosage uniformly in all the three groups. Vaccinees were assessed during prevaccination, followup and post vaccination periods for clinical, haematological, biochemical and immunological parameters for safety and immunogenicity. RESULTS: Successful follow-up in all parameters for four months could be achieved in 92.5% (222/240) for Genevac B study subjects and the same was 85% (68/80) and 80% (64/80) for Engerix B and Shanvac B respectively. While 100% seroconversion was observed in all the three groups, the rate of seroprotectivity was 99.5% by Genevac B, 98.5% by Engerix B and 98.4% for Shanvac B. However the difference was not statistically significant (p>0.05). The GMT values of anti HBs after one month of completion of the vaccination were 735.50, 718.23 and 662.20 mIU/mL respectively. No systemic reaction was either seen or reported by the volunteers during the vaccination process of Genevac B and other two vaccines. Clinical, haematological and biochemical safety parameters remained within normal limits throughout the study period. CONCLUSION: The study confirms that Genevac B, the new recombinant Hepatitis B vaccine has the acceptable international standards of safety and immunogenicity.

Relationship of plasmid profile with the antibiotic sensitivity pattern of helicobacter pylori isolates from peptic ulcer disease patients in Chennai.

PURPOSE: One hundred and ten Helicobacter pylori isolates from peptic ulcer disease patients and matched controls were analysed for any possible relationship between the presence of cryptic plasmids and their antibiotic sensitivity pattern. METHODS: Antral biopsies of patients with gastric and duodenal ulcer, gastric cancer, non ulcer dyspepsia and matched controls were cultured for H.pylori. Antibiotic susceptibility and MIC analysis of the clinical isolates was done by E-test. Plasmid profiles of the isolates were analysed using mini ultra prep plasmid kit. RESULTS: Out of the 110 isolates tested, 89.1% isolates were resistant to metronidazole, 10.9 % were resistant to clarithromycin and 0.9% were resistant to multiple drugs. Isolates harbouring plasmids were seen in all the groups and constituted 5.4% of total isolates. CONCLUSIONS: The presence of plasmids in the clinical isolates of H.pylori did not have any correlation with their antibiotic resistance pattern.

Need for specific & routine strategy for the diagnosis of genital chlamydial infection among patients with sexually transmitted diseases in India.

BACKGROUND & OBJECTIVES: With increasing burden of human immunodeficiency virus (HIV) infection acquired immunodeficiency syndrome (AIDS) in India, documentation on the epidemiology of genital chlamydial infections in high-risk patients with sexually transmitted diseases (STD) is of significant public health value. Specific diagnosis is essential to prevent the morbidity due to the chlamydial infection and to reduce the risk of acquiring HIV infection. The present study was undertaken to analyse the usefulness of culture and antigen detection by direct fluorescent antibody (DFA) test for assessing the rate of Chlamydia trachomatis infection in symptomatic patients and feasibility of these tests for routine adoption in Indian setting. METHODS: Clinically diagnosed patients of both sex (n=143) attending the Institute of Sexually Transmitted Diseases, Government General Hospital, Chennai who consented for the study, were enrolled. Clinical and demographic details were recorded on a stratified proforma. Genital swab specimens collected from them were subjected for culture using McCoy cell line and for antigen detection by DFA testing. RESULTS: C. trachomatis was isolated in 27 of the total 143 patients (18.9%). Culture positivity was seen in 11 of the 63 (17.5%) males and in 16 of 80 (20%) females. DFA detected C. trachomatis specific antigen in 35 patients (24.5%); 15 (23.8%) males and 20 (25%) females. The rate of C. trachomatis diagnosis increased to 25.2 per cent by adopting both the methods as against 18.9 per cent by culture only and 24.5 per cent by DFA only. No association of C. trachomatis infection with any predictable genitourinary symptom (s), was seen. INTERPRETATION & CONCLUSION: The findings show a high infection rate for C. trachomatis in symptomatic patients with STD. Clinical symptoms alone can be unreliable in specifically predicting infections with C. trachomatis. Specific diagnostic tests need to be recommended for routine inclusion in the STD diagnosis to facilitate risk reduction of HIV infection in STD patients.

Serodiagnosis of syphilis in a community: An evaluatory study.

PURPOSE: To analyse the prevalence of syphilis in the apparently healthy population and to provide data for implementation of the joint STD/HIV control programme, a population based study was undertaken by using 'probability proportional to size' cluster survey method in three randomly chosen districts of Tamil Nadu, India namely Dindigul, Ramnad and Tanjore. METHODS: Blood samples were collected from adults (n=1873) aged 15-45 years, from the selected households enrolled in this study. The sera were tested parallelly by rapid plasma reagin (RPR) and Treponema pallidum haemagglutination (TPHA) tests. Reactive samples by RPR and/or TPHA were later analysed by fluorescent treponemal antibody absorption (FTA-ABS) test. RESULTS: The prevalence of syphilis in the community of Tamil Nadu as per RPR positivity was 2.7% (50/1873) as against 0.7% by TPHA (13/1873). FTA-ABS positivity was observed in only 12 out of 48 (25%) RPR/TPHA reactive samples tested. By taking the positivity by two of the three tests, the community prevalence of acute ongoing syphilis in Tamil Nadu was determined as 1.1% (20/1873). CONCLUSIONS: The results confirmed that no single serological test for syphilis can act as the marker of ongoing acute infection in an apparently healthy population. The study suggests that for specific diagnosis of ongoing syphilis, the FTA-ABS test may be performed along with RPR and TPHA.

Prevalence of antibodies to hepatitis A and hepatitis E virus in urban school children in Chennai.

With similar feco-oral mode of transmission of Hepatitis A and E viruses, and improving levels of personal hygiene among higher socioeconomic population, periodic surveillance on HAV/HEV exposure pattern may be of immense public health value. One such attempt was made in Tamilnadu, India by analysing the presence of antibodies to HAV and HEV in 185 healthy children of 6 months to 12 years of age. While anti HAV positivity was 96.9% by 12 years of age, anti HEV positivity fluctuated between 5.3-16.7%. The study suggests the necessity for developing a vaccine for HEV to prevent the frequent occurrence of HEV outbreaks in India, since natural HEV exposure does not bestow significant protection as observed in HAV.

A study on the comparison between clinical and microbiological diagnoses of sexually transmitted diseases.

The efficacy of microbiological diagnosis in sexually transmitted diseases (STDs) has been evaluated in comparison with the clinical diagnosis. Amongst the clinical diagnoses of single STDs, syphilis, genital warts, gonorrhoea and herpes genitalis were the predominant ones. Syphilis was the most predominant infection in both the single and mixed STD infections in Chennai. Clinical diagnoses of trichomoniasis, genital chlamydiasis and genital herpes were more accurate and correlated well with laboratory investigations. On the other hand, clinical diagnoses of gonorrhoea, candidiasis and syphilis were less accurate. More over many of these cases, clinically diagnosed as single, infection, were also positive for other STDs in the laboratory investigations. Double infections were clinically diagnosed only in 7 cases as against 11 cases in microbiological tests and one triple infection diagnosed in microbiological tests was diagnosed only as single disease clinically. Therefore, the laboratory/microbiological investigations have been emphasised to have better accuracy of diagnosis of STDs.

Community prevalence of sexually transmitted diseases and human immunodeficiency virus infection in Tamil Nadu, India: a probability proportional to size cluster survey.

BACKGROUND: Human immunodeficiency virus (HIV) infection and AIDS is threatening the survival of many nations. To evaluate ongoing interventional strategies and burden of illness estimates, valid data on the prevalence of HIV are required. Often, in the absence of community prevalence data, estimates are based on surrogate markers such as prevalence of HIV in antenatal clinics. Even though the antenatal prevalence of HIV is easier to measure and can be repeated for evaluation, it is important to establish the association between antenatal and community prevalence of sexually transmitted diseases (STDs) and HIV, so that the validity of the estimates can be verified. METHODS: A 'probability proportional to size' cluster survey was conducted in three randomly selected districts of Tamil Nadu in India. The basic unit of the survey was households from rural and urban clusters. Adults 15-45 years of age from the selected households were eligible for recruitment. Demographic, behavioural and laboratory data were collected. Clinical examination was done to identify STD syndromes and blood, urine, vaginal/urethral and endocervical swabs were taken for laboratory diagnosis of STDs from the subjects. Direct smear examination for Trichomonas vaginalis; serological tests for syphilis, hepatitis B, HIV, herpes simplex virus 2, Chlamydia trachomatis; and culture of Neisseria gonorrhoeae and Haemophilus ducreyi were performed on the collected specimens. The data were analysed adjusting for cluster effect. RESULT: We selected and screened 1981 individuals (1157 women and 824 men) for STDs and HIV from 1114 households representing the 25 million projected adult population of Tamil Nadu. The overall community prevalence of STDs including HIV and hepatitis B in Tamil Nadu was 14.6% (CI: 14.1-15.1), and 8.3% (CI: 7.9-8.6) when HIV and hepatitis B were excluded. Community prevalence of HIV and hepatitis B infection was 1.8% (CI:1.7-1.9) and 5.3% (CI: 5.1-5.5), respectively. The distribution of HIV involved both rural and urban regions of Tamil Nadu. On clinical examination, at least one STD syndrome was noted in 486 (24.5%) of the women subjects; vaginal discharge was the most common and found in 421 women (38.4%). CONCLUSION: The prevalence of STD and HIV in Tamil Nadu is higher than expected and has extended into the non-high risk population (generalized epidemic).

Correlation of autoimmune reactivity with hepatitis B and C virus (HBV and HCV) infection in histologically proven chronic liver diseases.

PURPOSE: To comprehensively study the possibility of autoimmune reactivity by hepatitis viruses B and C (HBV &HCV) in Indian chronic liver disease (CLD) patients. METHODS: One hundred and sixty histopathologically proven CLD cases and 100 matched controls were analysed for viral serology for HBV and HCV and autoimmune serology for antinuclear antibody (ANA), anti smooth muscle antibody (ASMA) and Liver kidney microsomal antibody (LKM) using standard immunofluorescence technique. RESULTS: 43.7% of cases were chronic hepatitis B while 16.2% were positive for HCV. CLD-B cases showed ANA positivity in 27.1% and ASMA positivity in 25.7%. CLD-C cases revealed 26.9%, 46.1% and 11.1% positivity for ANA, ASMA and LKM antibodies respectively. These rates and titres of autoantibodies were statistically significant (p=< 0.02) when compared with that of controls. Conclusions: Based on the pattern of autoantibody positivity, it could be concluded that chronic HBV infection may induce autoimmune hepatitis (AIH) type I and chronic HCV infection might trigger AIH - Type II in Indian CLD cases.

Asymptomatic malarial parasitaemia in Tamil Nadu.

AIM: The aim of the study was to determine the community prevalence of asymptomatic malarial parasitaemia in the state of Tamil Nadu. METHODS: Free medical camps were organised in three randomly selected districts of Tamil Nadu, namely Dindigul, Ramnad and Thanjavur districts in November, 1997. Proportionate to population size cluster survey method was followed to collect peripheral blood smear by finger prick from 30 clusters in each district. Fifteen households were randomly selected from each district with the target age group of 15-45 years. Peripheral blood smears were stained by Leishman's stain and the slides were examined end to end by two independent experts to diagnose malarial parasites. RESULTS: The male:female ratio of the population studied was 1:1.6. Asymptomatic malaria was identified in 17 out of 569 individuals screened with a positive rate of 2.9% (CI 1.5-4.3). Out of the 17 malarial positive peripheral smears 15 were P. vivax and only two were P. falciparum with the predominance of gametocyte stage. CONCLUSION: This study reaffirms the prevalence of asymptomatic malaria in Tamil Nadu especially with P. vivax.

Identification of Pneumocystis carinii in induced sputum of AIDS patients in Chennai (Madras).

Induced sputum samples were collected from 32 AIDS patients with respiratory ailments. Pneumcystis carinii was demonstrated in 9 out of 32 AIDS cases by Indirect Immunofluorescence technique (HF). Four cases were positive by all the three techniques namely Giemsa staining, Toluidine blue staining and IIF, three were positive by both toluidine blue and IIF, and two were positive only by IIF. Among other microbial pathogens, acid fast bacilli was demonstrated in all the P carinii positive cases and Candida albicans in 53% AIDS cases from the induced sputum sample.

Study on cephalopod's ink for anti-retroviral activity.

Aqueous extracts of ink from four cephalopods, adult and young Sepiella inermis and Loligo duvaucelli were tested against Moloney murine leukaemia virus reverse transcriptase (MMLV RT). Ink from young cephalopods, S. intermis and L. duvaucelli showed strong inhibition of MMLV RT.

Antiretroviral drugs in the treatment of people living with human immunodeficiency virus: experience in a south Indian tertiary referral centre.

OBJECTIVE: A decrease in the number of new acquired immunodeficiency syndrome (AIDS) cases and AIDS--related deaths was seen in developed countries since 1996 due to the use of new combination of antiretroviral drugs. This retrospective study discusses the use of antiretroviral drugs in the treatment of people living with human immunodeficiency virus (HIV) in a developing country setting. METHODS: A retrospective case note analysis was done of patients receiving antiretroviral therapy at YRG Centre for AIDS Research and Education between Aug. 1996 and Feb. 1999. Out of 936 persons with HIV treated at this centre, 6.1% of the patients were prescribed three groups of drugs: Group A was the combination of the reverse transcriptase inhibitors (nRTI) zidovudine 600 mg daily and lamivudine 300 mg daily, Group B was the combination of zidovudine 600 mg daily, lamivudine 300 mg daily with protease inhibitor (PI) ritonavir 1200 mg daily and Group C was the combination of zidovudine 600 mg daily and lamivudine 300 mg daily with indinavir 2400 mg daily. Twenty HIV positive pregnant women were given zidovudine 500 mg daily during the third trimester (Group D) to reduce the vertical transmission of HIV. RESULTS: The mean CD4 gain was 188.0 cells/micro litre in Group A, 118.8 cell/microlitre in Group B and 223.3 cells/microlitre in Group C with a mean duration of 4.3, 3.1 and 3.5 months respectively. Many patients stopped antiretroviral drugs due to high cost of therapy. CONCLUSION: Hence, physicians should prescribe antiretroviral drugs only after ensuring that the patients can afford and will comply with a longterm treatment. Prescribing guidelines should be available to those working in this field and should be adhered to so that emergence of resistant strains could be prevented.