Publications (21)38.88 Total impact
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Article: Dengue fever with papilledema: a case of dengue-3 virus infection in central nervous system.
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ABSTRACT: Neurological manifestations of dengue fever are rarely reported during acute illness and clinical presentation commonly observed is of acute encephalitis or one of the post-infectious immune mediated manifestations. We describe a case of dengue fever having mild encephalopathy and papilledema at presentation. Twenty-year-old female presented with fever, headache and vomiting. On examination she did not have classical signs of dengue fever and was found to have bilateral papilledema on fundus examination. Detailed work-up did not reveal any other cause of papilledema. Diagnosis of dengue fever was established by blood IgM antibody test on day 7 of illness. Retrospective analysis of CSF (drawn on day 5 of illness) by RT-PCR assay showed a characteristic band of dengue-3 virus. Papilledema was transient and subsided following symptomatic treatment. The patient recovered from acute illness and follow-up was unremarkable. Especially in dengue endemic areas, in the patients having acute febrile illness with subtle signs and symptoms suggestive of CNS involvement, dengue virus infection should also be ruled out early in the clinical course.Journal of Clinical Virology 10/2006; 37(1):65-7. · 3.97 Impact Factor -
Article: Role of CSF serology in follow-up of subacute sclerosing panencephalitis patients on treatment.
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ABSTRACT: Subacute sclerosing panencephalitis (SSPE) is a progressive inflammatory disease of the central nervous system with poor prognosis and high mortality. No effective treatment has a proven role; oral isoprinosine and intrathecal administration of alpha-interferon may prolong survival. We report an unusual case of adult onset SSPE patient on treatment with significant clinical improvement, even in the absence of conversion to seronegativity in either CSF or serum, on follow-up serological examination.Indian Journal of Medical Microbiology 05/2006; 24(2):131-2. · 0.99 Impact Factor -
Article: Expression and humoral immune response to Hepatitis C virus using a plasmid DNA construct
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ABSTRACT: PURPOSE: The objective of this study was to clone a c-DNA fragment of hepatitis C virus in a eukaryotic expression vector and to measure the efficacy of humoral immune responses in mice inoculated with this recombinant plasmid. This study was an attempt to lay a foundation for HCV nucleic acid vaccine development in the future. METHODS: A c-DNA fragment of BK146, a clone of HCV type 1b, was sub-cloned into an eukaryotic expression vector pMT3. HepG2 and COS cells were transfected with this construct, named pMT3-BK146. The expression of HCV mRNA and proteins was studied by reverse transcribed polymerase chain reaction, radio Immunoprecipitation (RIPA) and immunofluorescence (IFA). The DNA of this construct was injected into the footpad of BALB/c mice and antibody response was tested by enzyme immunoassay and indirect immunofluorescence. RESULTS: COS and HepG2 cells transiently transfected with the recombinant plasmid pMT3-BK146 showed the expression of HCV proteins by RT-PCR, RIPA and immunofluorescence. This DNA clone when injected into Balb/c mice was able to generate specific antibody response to hepatitis C virus by ELISA and IFA. CONCLUSIONS: A c-DNA fragment of HCV cloned in an eukaryotic expression vector was able to express core protein. This DNA clone was also able to elicit antibody response in mice. This can be an initial step towards the development of a potential DNA vaccine for hepatitis C virus infection.Indian Journal of Medical Microbiology. 01/2003; -
Article: Foodborne outbreak caused by a Norwalk-like virus in India.
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ABSTRACT: An outbreak of acute gastroenteritis occurred in the nurses' hostel of a civil hospital in Delhi, after a farewell party involving 130 nurses and some of the housekeeping staff. All affected persons had eaten salad sandwiches at the party. Stool samples were collected from six of these patients on the second day of infection. All six samples, when tested for the presence of common bacteria, parasites, and rotavirus, were found to be negative. The clinical features of this outbreak matched the criteria set for outbreaks caused by Norwalk-like viruses (NLVs). Reverse transcription-polymerase chain reaction (RT-PCR) was carried out on these six samples, using primers from the RNA-dependent RNA polymerase (RdRp) gene of NLVs. Immunoelectron microscopy was carried out on two of the samples, using convalescent phase serum. All six samples were positive for genogroup (GG) II NLVs by RT-nested PCR. Aggregates of 32-nm viral particles were visualized by immunoelectron microscopy in one of the two samples. Sequencing of the RdRp gene was done on amplicons from three samples; phylogenetic analysis placed the isolates NDV/1999 in a Toronto virus cluster of GG II NLVs. This is the first report of a food-borne outbreak attributable to NLVs from India.Journal of Medical Virology 09/2002; 67(4):603-7. · 2.82 Impact Factor -
Article: Predominace of a novel Mycobacterium tuberculosis genotype in the Delhi region of India.
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ABSTRACT: Using IS 6110 -restriction fragment length polymorphism (RFLP) and spoligotyping, genetic variations of 83 Mycobacterium tuberculosis strains isolated from tuberculosis patients from two wards in a hospital in Delhi and a rural chest clinic near Delhi were analysed. The vast majority of the isolates (75%) were closely related and this novel genogroup was designated the 'Delhi type'. Both drug-sensitive and drug-resistant strains were found among strains of this genogroup. A minority of the strains harboured a single IS 6110 copy and only one strain belonged to the Beijing genotype, a genotype that is predominant in other parts of Asia. A comparison of the RFLP and spoligotype with existing data suggests that the predominance of Delhi genogroup is geographically limited to the Indian subcontinent and perhaps to specific regions in India. Despite the high prevalence of the M. tuberculosis strains of the Delhi type, the strains could easily be discriminated due to polymorphisms in the IS 6110 patterns. Future studies may disclose the genetic characteristics of strains belonging to the Delhi genotype, analogous to the recently observed virulence among the Beijing genogroup.Tuberculosis 02/2002; 82(2-3):105-12. · 3.47 Impact Factor -
Article: Polymerase chain reaction in clinically suspected genitourinary tuberculosis: comparison with intravenous urography, bladder biopsy, and urine acid fast bacilli culture.
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ABSTRACT: To evaluate the role of urinary polymerase chain reaction (PCR) in the detection of Mycobacterium tuberculosis (MTb) in patients with a clinical suspicion of genitourinary tuberculosis (GUTB) and to compare its sensitivity with intravenous urography (IVU), bladder biopsy, and urine culture for acid fast bacilli (AFB). The study was carried out between September 1997 and December 1998 in 42 patients with a clinical suspicion of GUTB. Their clinical features, organ involvement, and investigation results were studied. The diagnostic yield of urinary PCR for MTb and its sensitivity in comparison with routine urine AFB culture, bladder biopsy, and IVU were assessed. There were 25 male and 17 female patients, with a mean age of 31.04 years. Patients suspected of having GUTB most often presented with irritative voiding symptoms. Two patients had abnormal renal parameters. Of the 42 patients clinically suspected of having GUTB, radiologic abnormalities suggestive of GUTB were found in 37 (88.09%); MTb was isolated in the urine AFB culture in 13 (30.95%); bladder biopsy was positive in 11 (45.83%); and urinary PCR for MTb was positive in 34 cases (80.95%). Of 35 cases of proven GUTB, IVU was suggestive of the diagnosis in 32 (91.42%) and MTb was isolated in the urine AFB culture in 13 cases (37.14%). Bladder biopsy was positive in 11 (45. 83%) of 24 patients in whom biopsy was taken, and urinary PCR for MTb was positive in 33 (94.29%). A high index of suspicion is necessary for a diagnosis of GUTB. In clinically suspected cases, IVU may be suggestive of GUTB, but it is not specific. In the present study, IVU was suggestive in 88.09% of patients. MTb was isolated in the urine AFB culture in only 37.14% of patients, and bladder biopsy was positive in 45.83%. Urinary PCR for MTb was the most sensitive indicator and was positive in 94.29% of patients. It is evident from this series that PCR provides a much faster diagnosis of urinary MTb. It is a rapid, sensitive, and specific diagnostic method and avoids a delay in starting treatment.Urology 11/2000; 56(4):570-4. · 2.43 Impact Factor -
Article: Rapid detection of respiratory viruses by centrifugation enhanced cultures from children with acute lower respiratory tract infections.
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ABSTRACT: Acute respiratory tract infection (ARI) is the major cause of morbidity and mortality in young children in developing countries. Information on viral aetiology in ARI in India is very limited. The aim of the study was to define the role of viruses in acute lower respiratory tract infections (ALRTI) in children in India using centrifugation enhanced cultures followed by indirect immunofluorescence (IIF). Nasopharyngeal aspirates (NPAs) were collected from children from September 1995 to April 1997, attending paediatric clinic of All India Institute of Medical Sciences (AIIMS) with symptoms of ALRTI. Virus isolation was done by centrifugation enhanced cultures using HEp-2, LLC-MK2 and MDCK cells. The viruses were identified at 24-48 h post inoculation by IIF staining using monoclonal antibodies to respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus and adenovirus. Of 200 NPA samples, 89 (44.5%) were positive for one or more viral pathogens. RSV was detected in 34 (17%) of all ALRTI cases followed by influenza viruses in 29 (14.5%), PIVs in 23 (11.5%) and adenoviruses in three (1.5%). In 79 children with bronchiolitis, RSV was most frequently isolated (25%) pathogen, while in bronchopneumonia cases (101) the most common viral pathogen was influenza virus (17%). In eight cases (4%) of ALRTI dual infections were detected. In 100 NPA specimens IIF staining on direct cell smears was carried out and viruses were detected in only 17%. RSV and influenza virus infection peaked from September to December, where as PIV infections were more frequent from January to April. Respiratory viruses accounted for 44.5% of cases of ALRTI in India and the results of viral aetiology could be given in 24-48 h using centrifugation enhanced cultures. RSV was the most common viral agent associated with ALRTI in children under 5 years of age with greater association with bronchiolitis.Journal of Clinical Virology 03/2000; 16(1):41-7. · 3.97 Impact Factor -
Article: Dengue virus infection during post-epidemic period in Delhi, India.
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ABSTRACT: Dengue fever (DF) and dengue hemorrhagic fever (DHF) are major public health problems in India. During the period following an epidemic, a study was carried out using virological and serological tests for confirmation of suspected cases of dengue virus infection in fever cases presenting to the All India Institute of Medical Sciences. Serum samples of suspected DF/DHF cases were processed from January to December 1997. In 37 samples from patients with fever of less than 5-day duration, received on ice, virus isolation was attempted in C6/36 clone of Aedes albopictus cell line, followed by indirect fluorescent antibody staining with monoclonal antibodies to dengue viruses 1 to 4. One hundred and forty-three serum samples from patients with more than 5 days fever were tested for dengue specific IgM antibody by either MAC-ELISA or a rapid immunochromatographic assay. Dengue virus type 1 was demonstrated by culture in 8 (21.6%) of 37 serum samples and IgM antibody could be detected in 42 (29.4%) of the 143 serum samples by the serological methods. The peak of dengue virus infection was seen from September to November 1997.The Southeast Asian journal of tropical medicine and public health 10/1999; 30(3):507-10. · 0.60 Impact Factor -
Article: Role of platelet transfusion in dengue hemorrhagic fever.
Indian pediatrics 06/1998; 35(5):452-5. · 1.05 Impact Factor -
Article: Evaluation of polymerase chain reaction for rapid diagnosis of clinically suspected tuberculous meningitis.
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ABSTRACT: Since conventional bacteriological methods rarely detect Mycobacterium tuberculosis in cerebrospinal fluid (CSF) and are of limited use in the diagnosis of tuberculous meningitis (TBM), clinical features suggestive of TBM supported by indirect evidence such as CSF examination and computerized tomography (CT) of the head have been used for the early diagnosis of TBM. We evaluated the efficacy of polymerase chain reaction (PCR) in the diagnosis of TBM. Coded CSF samples from 40 patients with TBM and from 49 patients with other neurological disorders were processed. In the absence of a reliable sensitive and specific test for M. tuberculosis in CSF, we used a set of established clinical criteria as the gold standard. Accordingly, the patients were divided into definite, highly probable, probable and possible TBM. The samples were decoded only after completion of the laboratory tests. PCR was positive in 2/4, 19/20, 13/16 patients with highly probable, probable and possible TBM respectively. None of the samples were positive by conventional bacteriological methods. However, 3/49 CSF samples from non-TBM patients were also found positive by PCR. PCR detected M. tuberculosis genomic DNA in the CSF of 85% of clinically suspected TBM cases and 6.1% of non-tuberculous controls. PCR, along with the suggested clinical criteria, offers a rapid and fairly accurate diagnosis of TBM.Tubercle and Lung Disease 09/1996; 77(4):353-7. -
Article: Classification of rotavirus into G and P types with specimens from children with acute diarrhea in New Delhi, India.
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ABSTRACT: Sixty rotavirus-positive stool specimens from children with diarrhea were classified into G and P genotypes. G typing was done by PCR and then by hybridization with G type-specific (G1 to G4) oligonucleotide probes, whereas nested PCR was performed for P typing. Thirty-nine samples could be classified into both G and P types, of which P8G1 and P4G2 (33% each) genotypes were predominant. The P6 genotype was detected in four children with diarrhea.Journal of Clinical Microbiology 07/1996; 34(6):1592-4. · 4.15 Impact Factor -
Article: Concurrent infection by two dengue virus serotypes among dengue patients.
Indian Journal of Medical Microbiology 26(4):402-3. · 0.99 Impact Factor -
Article: Acute hemorrhagic conjunctivitis due to enterovirus 70 in India.
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ABSTRACT: An outbreak of acute hemorrhagic conjunctivitis occurred in Delhi, India, during August and September 1996. The etiologic agent was confirmed as enterovirus type 70 by a modified centrifugation-enhanced culture method followed by immunofluorescence and neutralization tests. After nearly a decade, this virus is reemerging as a cause of acute hemorrhagic conjunctivitis in India.Emerging infectious diseases 5(2):267-9. · 6.17 Impact Factor -
Article: Diagnosis of pulmonary tuberculosis by polymerase chain reaction for MPB64 gene: an evaluation in a blind study.
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ABSTRACT: Polymerase chain reaction (PCR) has been found to be a sensitive and rapid method to confirm a clinical diagnosis of tuberculosis. We evaluated PCR for M. tuberculosis complex specific MPB64 gene for the diagnosis of pulmonary tuberculosis, in a double blind study. One hundred and eighty-two clinical samples (sputum, bronchioalveolar lavage and pleural fluid) from patients with a clinical diagnosis of pulmonary tuberculosis and 72 samples from patients with non-tubercular pulmonary lesions and normal healthy individuals were included. The samples were coded and clinical details were concealed from the laboratory, where conventional diagnostic methods and PCR were carried out independent of each other. On decoding and analysing the data, PCR was positive in 59% of single sputum samples from clinically diagnosed pulmonary tuberculosis, while M. tuberculosis could be grown in 18% of the samples. PCR could identify M. tuberculosis in 81.8% of the culture positive sputum samples. PCR was also positive in 71.4% of bronchioalveolar lavage (BAL) fluid and 60.7% pleural fluid samples from clinically suspected cases, which were mostly culture negative. On comparison with response to treatment, PCR was positive in 79.5% of patients who improved on anti-tuberculosis treatment, with a positive predictive value of 92%. PCR for MPB64 gene provides a useful alternative for the diagnosis of pulmonary tuberculosis from sputum and paucibacillary samples like BAL and pleural fluid in which conventional methods show low sensitivity, especially in areas from which strains show a low copy number of other PCR targets like the IS 6110 insertion sequence.The Indian journal of chest diseases & allied sciences 40(1):5-16. -
Article: Vaccines against enteric infections.
Tropical gastroenterology: official journal of the Digestive Diseases Foundation 13(3):96-101. -
Article: Multidrug resistant Salmonella typhi in Delhi.
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ABSTRACT: In 1990, we isolated 158 strains of Salmonella typhi from blood cultures of patients suffering from typhoid fever. Seventy nine (50%) of these isolates were found to be simultaneously resistant to chloramphenicol, ampicillin and cotrimoxazole. These strains were also resistant to streptomycin and tetracycline, but sensitive to gentamicin, amikacin and cephalexin. The minimum inhibitory concentrations of chloramphenicol and trimethoprim for a representative number of these strains were found to be greater than 1024 micrograms/ml and greater than 128 micrograms/ml respectively. Majority of the multidrug resistant (MDR) strains tested against cefotaxime (23/23), ciprofloxacin (38/38) and amoxycillin plus clavulanic acid (23/24) were sensitive to these drugs.The Indian Journal of Pediatrics 59(2):221-4. · 0.52 Impact Factor -
Article: Polymerase chain reaction in clinically suspected genitourinary tuberculosis: comparison with intravenous urography, bladder biopsy, and urine acid fast bacilli culture
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ABSTRACT: Objectives. To evaluate the role of urinary polymerase chain reaction (PCR) in the detection of Mycobacterium tuberculosis (MTb) in patients with a clinical suspicion of genitourinary tuberculosis (GUTB) and to compare its sensitivity with intravenous urography (IVU), bladder biopsy, and urine culture for acid fast bacilli (AFB).Methods. The study was carried out between September 1997 and December 1998 in 42 patients with a clinical suspicion of GUTB. Their clinical features, organ involvement, and investigation results were studied. The diagnostic yield of urinary PCR for MTb and its sensitivity in comparison with routine urine AFB culture, bladder biopsy, and IVU were assessed.Results. There were 25 male and 17 female patients, with a mean age of 31.04 years. Patients suspected of having GUTB most often presented with irritative voiding symptoms. Two patients had abnormal renal parameters. Of the 42 patients clinically suspected of having GUTB, radiologic abnormalities suggestive of GUTB were found in 37 (88.09%); MTb was isolated in the urine AFB culture in 13 (30.95%); bladder biopsy was positive in 11 (45.83%); and urinary PCR for MTb was positive in 34 cases (80.95%). Of 35 cases of proven GUTB, IVU was suggestive of the diagnosis in 32 (91.42%) and MTb was isolated in the urine AFB culture in 13 cases (37.14%). Bladder biopsy was positive in 11 (45.83%) of 24 patients in whom biopsy was taken, and urinary PCR for MTb was positive in 33 (94.29%).Conclusions. A high index of suspicion is necessary for a diagnosis of GUTB. In clinically suspected cases, IVU may be suggestive of GUTB, but it is not specific. In the present study, IVU was suggestive in 88.09% of patients. MTb was isolated in the urine AFB culture in only 37.14% of patients, and bladder biopsy was positive in 45.83%. Urinary PCR for MTb was the most sensitive indicator and was positive in 94.29% of patients. It is evident from this series that PCR provides a much faster diagnosis of urinary MTb. It is a rapid, sensitive, and specific diagnostic method and avoids a delay in starting treatment.Urology. -
Article: Expression and humoral immune response to hepatitis C virus using a plasmid DNA construct.
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ABSTRACT: The objective of this study was to clone a c-DNA fragment of hepatitis C virus in a eukaryotic expression vector and to measure the efficacy of humoral immune responses in mice inoculated with this recombinant plasmid. This study was an attempt to lay a foundation for HCV nucleic acid vaccine development in the future. A c-DNA fragment of BK146, a clone of HCV type 1b, was sub-cloned into an eukaryotic expression vector pMT3. HepG2 and COS cells were transfected with this construct, named pMT3-BK146. The expression of HCV mRNA and proteins was studied by reverse transcribed polymerase chain reaction, radio Immunoprecipitation (RIPA) and immunofluorescence (IFA). The DNA of this construct was injected into the footpad of BALB/c mice and antibody response was tested by enzyme immunoassay and indirect immunofluorescence. COS and HepG2 cells transiently transfected with the recombinant plasmid pMT3-BK146 showed the expression of HCV proteins by RT-PCR, RIPA and immunofluorescence. This DNA clone when injected into Balb/c mice was able to generate specific antibody response to hepatitis C virus by ELISA and IFA. A c-DNA fragment of HCV cloned in an eukaryotic expression vector was able to express core protein. This DNA clone was also able to elicit antibody response in mice. This can be an initial step towards the development of a potential DNA vaccine for hepatitis C virus infection.Indian Journal of Medical Microbiology 21(2):93-7. · 0.99 Impact Factor -
Article: Myocardial dysfunction in children with dengue haemorrhagic fever.
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ABSTRACT: Dengue fever/dengue haemorrhagic fever/dengue shock syndrome is a serious health problem in tropical countries. Intravascular fluid depletion due to capillary leak is presumed to be the cause of hypotension in dengue haemorrhagic fever. The treatment guidelines of the World Health Organization lay stress primarily on monitoring and fluid replacement therapy. During the 1996 epidemic in New Delhi, we observed problems in fluid management of such children and prospectively looked for myocardial dysfunction as an additional factor for hypotension. Fifty-four children (< 12 years old) admitted to the All India Institute of Medical Sciences, New Delhi after 15 October 1996 with various grades of the disease, who were fit to be shifted to the echocardiography laboratory, were examined clinically and subjected to a detailed M-mode, 2-dimensional and colour doppler echocardiography. Ejection fractions (Teichholz/Modified Simpson's) and shortening fractions were calculated. Ejection fraction by modified Simpson's rule was reduced (< 50%) in 9/54 (16.7%) children; 2 of these had significant reductions (< 35%). These 9 children belonged to all stages of clinical severity. Three of these 9 children who had a repeat echocardiogram within 2 months of the illness had improved ejection fractions. The role of myocardial dysfunction remains to be defined as there was no correlation with clinical severity. Myocardial functions need to be assessed in patients with this disease, especially those who have persistent hypotension in spite of adequate hydration.The National medical journal of India 11(2):59-61. · 0.60 Impact Factor -
Article: The first major outbreak of dengue hemorrhagic fever in Delhi, India.
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ABSTRACT: India An outbreak of dengue hemorrhagic fever/dengue shock syndrome (DHS/DSS) occurred in 1996 in India in and near Delhi. The cause was confirmed as dengue virus type 2, by virus cultivation and indirect immunofluorescence with type-specific monoclonal antibodies. This is the largest such outbreak reported from India, indicating a serious resurgence of dengue virus infection.Emerging infectious diseases 5(4):589-90. · 6.17 Impact Factor
Top co-authors
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Institutions
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1999–2002
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All India Institute of Medical Sciences
- • Department of Microbiology
- • Department of Urology
New Delhi, NCT, India
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