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S P Thyagarajan

Publications and source records attributed to S P Thyagarajan.

At least 19 recordsLinked to original sources
PubMed2005

Performance of two commercial enzyme-linked immunosorbent assay kits using recombinant glycoprotein G2 antigen for detection of herpes simplex virus type 2 specific antibodies.

For 93 stored serum samples tested by HerpeSelect2 and the Euroimmun enzyme-linked immunosorbent assay for detection of herpes simplex virus type 2-specific immunoglobulin G antibodies, the concordance of positive and negative results was 100%. Moreover, all the results that were equivocal by HerpeSelect2 (negative by Euroimmun) were confirmed as being negative by a Western blot assay.

Antibodies, Viral↗
PubMed2005

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.

Adult↗
PubMed2005

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.

Adolescent↗
PubMed2005

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.

Blotting, Western↗
PubMed2004

Chlamydia trachomatis genital infection in apparently healthy adult population of Tamil Nadu, India: a population-based study.

Since the epidemiology of Chlamydia trachomatis infection in apparently healthy population has not been studied in India, a population-based study was conducted in the state of Tamil Nadu, India in order to analyse the prevalence of genital chlamydial infections in the community and to implement control programmes. A representative sample was taken from three randomly selected districts by using the 'probability proportional to size' cluster survey method. Households were the basic units of clusters. Adults aged 15-45 years, pre-identified from the selected households were enrolled during the medical camps conducted for a major study on community prevalence of sexually transmitted diseases in Tamil Nadu. Blood and urine samples collected from the study subjects were tested by enzyme-linked immunosorbent assay (ELISA) for anti-chlamydial IgM antibodies and by the commercial Amplicor polymerase chain reaction (PCR) test for chlamydial DNA. The prevalence of anti-C. trachomatis antibodies determined by IgM-ELISA was 2.4% (95% CI 1.6%-3.2%). The prevalence of genital chlamydial infection determined by PCR was 1.1% (95% CI 0.5%-1.7%). Majority of the detected infections (68.8%) were asymptomatic. This is the first Indian report on the prevalence of genital chlamydial infections in the general population. It is concluded that this study provides evidence for a substantial burden of approximately 10 million asymptomatic genital chlamydial infection cases in the sexually active age groups in the general population of India.

Adolescent↗
PubMed2004

Genital syndromes and syndromic management of vaginal discharge in a community setting.

The objective of the study was to determine the community prevalence of genital syndromes in women and evaluate the syndromic management of vaginal discharge in this setting. A representative sample for the state of Tamilnadu was chosen using probability proportional to size cluster technique. Thirty clusters were selected from three districts. Demographic, sexual behaviour, risk factors, clinical and laboratory data were collected from the selected population using a structured questionnaire. Direct smear examination for Trichomonas vaginalis, culture for Neisseria gonorrhoeae and Haemophilus ducreyi, serological tests for syphilis (RPR and TPHA), hepatitis B (Hbs Ag ELISA), IgM and IgG antibodies to HSV2 (Novum diagnostics, Germany) and PCR test for detection of C. trachomatis from urine were done. There were 1157 women in the selected population. On examination, vaginal discharge was the most common genital syndrome (38.4%). The sensitivity, specificity, positive and negative predictive value of vaginal discharge as a marker for STD in women was found to be 43.3%, 61.6%, 10.7% and 91.1%, respectively. We concluded that treatment on the basis of syndromic management would result in over-treatment of 90% of women with vaginal discharge.

Adult↗
PubMed2003

Geographical difference in antimicrobial resistance pattern of Helicobacter pylori clinical isolates from Indian patients: Multicentric study.

AIM: To assess the pattern of antimicrobial resistance of Helicobacter pylori isolates from peptic ulcer disease patients of Chandigarh, Delhi, Lucknow, Hyderabad and Chennai in India, and to recommend an updated anti-H. pylori treatment regimen to be used in these areas. METHODS: Two hundred and fifty-nine H. pylori isolates from patients with peptic ulcer disease reporting for clinical management to the Post Graduate Institute of Medical Education and Research, Chandigarh; All India Institute of Medical Sciences, New Delhi; Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow; Deccan College of Medical Sciences and Allied Hospitals, Hyderabad; and hospitals in Chennai in collaboration with the Dr ALM Post Graduate Institute of Basic Medical Sciences were analyzed for their levels of antibiotic susceptibility to metronidazole, clarithromycin, amoxycillin, ciprofloxacin and tetracycline. The Epsilometer test (E-test), a quantitative disc diffusion antibiotic susceptibility testing method, was adopted in all the centers. The pattern of single and multiple resistance at the respective centers and at the national level were analyzed. RESULTS: Overall H. pylori resistance rate was 77.9% to metronidazole, 44.7% to clarithromycin and 32.8% to amoxycillin. Multiple resistance was seen in 112/259 isolates (43.2%) and these were two/three and four drug resistance pattern to metronidazole, clarithromycin, amoxycillin observed (13.2, 32 and 2.56%, respectively). Metronidazole resistance was high in Lucknow, Chennai and Hyderabad (68, 88.2 and 100%, respectively) and moderate in Delhi (37.5%) and Chandigarh (38.2%). Ciprofloxacin and tetracycline resistance was the least, ranging from 1.0 to 4%. CONCLUSION: In the Indian population, the prevalence of resistance of H. pylori is very high to metronidazole, moderate to clarithromycin and amoxycillin and low to ciprofloxacin and tetracycline. The rate of resistance was higher in southern India than in northern India. The E-test emerges as a reliable quantitative antibiotic susceptibility test. A change in antibiotic policy to provide scope for rotation of antibiotics in the treatment of H. pylori in India is a public health emergency.

Amoxicillin↗
PubMed2003

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.

Age Distribution↗
PubMed2003

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.

Adult↗
PubMed2002

Natural history of human immunodeficiency virus disease in southern India.

There are few reports of the natural history of human immunodeficiency virus (HIV) infection from Asia. In a retrospective analysis of 594 patients (72.9% male; baseline CD4 cell count, 216 cells/microL) receiving care at YRG Center for AIDS Research and Education, a tertiary HIV referral center in southern India, the mean duration of survival from serodiagnosis was 92 months. Ninety-three percent of the patients acquired infection through heterosexual contact. The most common acquired immune deficiency syndrome-defining illnesses were pulmonary tuberculosis (49%; median duration of survival, 45 months), Pneumocystis carinii pneumonia (6%; median duration of survival, 24 months), cryptococcal meningitis (5%; median duration of survival, 22 months), and central nervous system toxoplasmosis (3%; median duration of survival, 28 months). Persons with a CD4 lymphocyte count of <200 cells/microL were 19 times (95% confidence interval [CI], 5.56-64.77) more likely to die than were those with CD4 cell count of >350 cells/microL. Patients who had > or =1 opportunistic infection were 2.6 times more likely to die (95% CI, 0.95-7.09) than were those who did not have an opportunistic infection. Antiretroviral therapy for patients with low CD4 lymphocyte counts improved the odds of survival (odds ratio, 5.37; 95% CI, 1.82-15.83).

Adolescent↗
PubMed2002

Total lymphocyte count (TLC) is a useful tool for the timing of opportunistic infection prophylaxis in India and other resource-constrained countries.

BACKGROUND: In most resource-constrained countries, CD4 cell count testing is prohibitively expensive for routine clinical use and is not widely available. As a result, physicians are often required to make decisions about opportunistic infection (OI) chemoprophylaxis without a laboratory evaluation of HIV stage and level of immunosuppression. OBJECTIVES To evaluate the correlation of total lymphocyte count (TLC), an inexpensive and widely available parameter, to CD4 count. To determine a range of TLC cutoffs for the initiation of OI prophylaxis that is appropriate for resource-constrained settings. METHODS: Spearman correlation between CD4 count and TLC was assessed in patients attending an HIV/AIDS clinic in South India. Positive predictive value (PPV), negative predictive value (NPV), and sensitivity and specificity of various TLC cutoffs were computed for CD4 count <200 cells/mm3 and <350 cells/mm3. Correlation and statistical indices computed for all patients and for patients dually infected with HIV and active tuberculosis. RESULTS: High degree of correlation was noted between 650 paired CD4 and TLC counts (r = 0.744). TLC <1400 cells/mm3 had a 76% PPV, 86% NPV, and was 73% sensitive, 88% specific for CD4 count <200 cells/mm3. TLC <1700 cells/mm3 had a 86% PPV, 69% NPV, and was 70% sensitive, 86% specific for CD4 count <350 cells/mm3. The cost of a single CD4 count in India is approximately 30 US dollars, whereas the cost of a single TLC is 0.80 US dollars. CONCLUSION: TLC could serve as a low-cost tool for determining both a patient's risk of OI and when to initiate prophylaxis in resource-constrained settings. PPV, NPV, sensitivity, and specificity maximally aggregated at TLC <1400 cells/mm3 for CD4 <200 cell/mm3 and TLC <1700 cells/mm3 for CD4 <350 cells/mm3. Selection of appropriate TLC cutoffs for prophylaxis administration should be made on a regional basis depending on OI incidence, antimicrobial resistance patterns, and availability of the antimicrobials.

AIDS-Related Opportunistic Infections↗
PubMed2002

Herbal medicines for liver diseases in India.

The use of natural remedies for the treatment of liver diseases has a long history, starting with the Ayurvedhic treatment, and extending to the Chinese, European and other systems of traditional medicines. The 21st century has seen a paradigm shift towards therapeutic evaluation of herbal products in liver diseases by carefully synergizing the strengths of the traditional systems of medicine with that of the modern concept of evidence-based medicinal evaluation, standardization of herbal products and randomized placebo controlled clinical trials to support clinical efficacy. The present review provides the status report on the scientific approaches made to herbal preparations used in Indian systems of medicine for the treatment of liver diseases. In spite of the availability of more than 300 preparations for the treatment of jaundice and chronic liver diseases in Indian systems of medicine using more than 87 Indian medicinal plants, only four terrestrial plants have been scientifically elucidated while adhering to the internationally acceptable scientific protocols. In-depth studies have proved Sylibum marianum to be anti-oxidative, antilipidperoxidative, antifibrotic, anti-inflammatory, immunomodulating and liver regenerative. Glycyrrhiza glabra has been shown to be hepatoprotective and capable of inducing an indigenous interferon. Picrorhiza kurroa is proved to be anti-inflammatory, hepatoprotective and immunomodulatory. Extensive studies on Phyllanthus amarus have confirmed this plant preparation as being anti-viral against hepatitis B and C viruses, hepatoprotective and immunomodulating, as well as possessing anti-inflammatory properties. For the first time in the Indian systems of medicine, a chemo-biological fingerprinting methodology for standardization of P. amarus preparation has been patented.

Humans↗
PubMed2002

Dried blood spots (DBS): a valuable tool for HIV surveillance in developing/tropical countries.

Dried blood spots (DBS) on filter paper have been used as a practical method of sample collection in sero-surveillance studies of numerous diseases. DBS may be particularly useful for HIV screening in remote areas, in which unrefrigerated transfer time to a laboratory may take a number of days. In this study, we evaluate the ability to detect human immunodeficiency virus (HIV) type-1 antibodies from DBS that have been subjected to a tropical climate in southern India for 6 days. DBS were prepared from blood samples of 59 known HIV-positive individuals and 30 known HIV-negative individuals. ELISA and Western blot results from DBS that were subjected to a mean temperature of 35.8 degrees C and humidity of 73% for 6 days had a sensitivity of 100% and 92%, respectively, and a specificity of 100% and 100%, respectively. Based on these findings, we conclude that DBS sampling could serve as a cost-effective and convenient tool for widespread HIV sero-surveillance in remote areas within tropical countries.

AIDS Serodiagnosis↗
PubMed2002

Molecular typing of Neisseria gonorrhoeae from hospital and community isolates by restriction fragment length polymorphism.

Strains of Neisseria gonorrhoeae are generally characterized by auxotyping, serotyping, plasmid profile, antibiotic sensitivity and deoxyribonucleic acid (DNA) amplification fingerprinting. The aim of this study was to analyse the generation of restriction fragment length polymorphism (RFLP) patterns by BgIII digestion of total genomic DNA of N. gonorrhoeae isolated from the community (n =30) and the hospital (n =15) and to establish an association with serogrouping and antibiogram. The RFLP patterns produced by BgIII restriction digestion showed 7 different patterns among 30 community isolates and 9 different patterns among 15 hospital isolates. 66.7% of isolates belonged to serogroup WI. Penicillin resistance was observed in 46.7% of community isolates and 66.7% hospital isolates. However, penicillinase producing N. gonorrhoeae (PPNG) were lower in the community (6.6%) than in the hospital isolates (53.3%). PPNG strains were more often seen in serogroup WI. This is the first Indian report on RFLP genotype pattern in N. gonorrhoeae. We noted differences in RFLP genotypes of the community (RFLP types 1, 2, 3, 4, 5 and 7) and hospital strains (RFLP types 6 and 8), while no differences in the serogroup were observed. Ciprofloxacin resistance was 20.0% and 26.6% in the community and hospital isolates, respectively. Ceftriaxone emerges as the current drug of choice for an effective policy of antibiotic treatment of gonorrhoea through syndromic management in developing countries.

Anti-Bacterial Agents↗
PubMed2002

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.

Adolescent↗
PubMed2001

Efficacy of fluconazole and itraconazole in the treatment of oral candidiasis in HIV patients.

A total of 46 strains of Candida were collected from HIV infected patients, of which 25 strains were isolated from patients with oral candidiasis, and 21 strains were from mouthwash samples of asymptomatic carriers. The most common species isolated was Candida albicans (73.9%), followed by Candida tropicalis (21.7%). In vitro susceptibility of the strains to fluconazole and itraconazole was tested using minimum inhibitory concentration (MIC) studies by agar dilution technique. Out of the 18 strains of C. albicans isolated from mouthwash samples, four were resistant to fluconazole whereas only two were resistant to itraconazole. Out of 16 strains of C. albicans isolated from oral lesions, one was resistant to fluconazole where as all were sensitive to itraconazole. Among the other species of Candida tested, C. tropicalis gave higher MIC values to both drugs than other species such as Candida guillermondii and Candida krusei. In vitro MIC values correlated well with in vivo responses in patients. Hence, itraconazole may be used as an alternative in the treatment of candidiasis, which does not respond to fluconazole therapy.

AIDS-Related Opportunistic Infections↗
PubMed2001

Profile of hepatocellular carcinoma in India: an insight into the possible etiologic associations.

BACKGROUND: Several etiologic factors including hepatitis viruses, alcohol and aflatoxin have been implicated in the pathogenesis of hepatocellular carcinoma (HCC). There is, however, limited information from the Indian subcontinent. METHODS: Seventy-four consecutive cases of HCC were studied. A detailed history, tests for hepatitis B virus (HBV; HBsAg, HBeAg, anti-HBe, IgG anti-HBc, anti-HBs and HBV-DNA), hepatitis C virus (HCV; anti-HCV and HCV-RNA) infection, liver histopathology and HBV-DNA integration by using Southern blot hybridization were studied. A p53 gene mutation was also studied by using PCR and single-strand conformation polymorphism. RESULTS: Hepatocellular carcinoma patients were predominantly males (mean age 49.5 +/- 14.0 years). Portal hypertension and cirrhosis were seen in 56 (76%) patients, more often (P < 0.05) in viral marker positive cases. Forty-five percent of patients had features of hepatic decompensation at presentation. Evidence of HBV infection was present in 53 (71%) patients. Twenty-six (49%) of these patients had either HBeAg + ve, HBV-DNA + ve (n = 12), or HBsAg - ve, HBV-DNA + ve (n = 14) forms of HBV infection. Hepatitis B virus DNA integration in the liver tissue was seen in 10 of 17 (59%) patients. Infection with HCV alone was detected in three (4%) and dual HBV and HCV infection in six (8%) patients. A majority (78.5%) of the chronic alcoholics had associated viral infection. The etiology of HCC remained undetermined in 15 (20%) patients. The p53 gene mutations were detected only in three of 21 (14%) liver tissues. Aflatoxin toxicity, oral contraceptive use or metabolic disorder were not seen. CONCLUSIONS: In India: (i) HBV infection is the predominant factor for the development of HCC, often related to mutant forms of HBV; (ii) a majority of the HCC patients have overt cirrhosis of the liver; and (iii) HCV and alcohol per se are uncommonly associated.

Aflatoxin B1↗