Serological & molecular approaches for diagnosis of leptospirosis in a tertiary care hospital in north India: a 10-year study.

BACKGROUND & OBJECTIVES: Leptospirosis, a spirochetal zoonosis, is underreported from the northern States of India. This study reports results of a 10-year retrospective sero-epidemiological survey of leptospirosis conducted in a tertiary care hospital in New Delhi, India. METHOD: A total of 1453 patients clinically suspected for leptospirosis were included and investigated initially by IgM ELISA. A proportion of these were subjected to culture, microscopic agglutination test (MAT) and polymerase chain reaction (PCR). RESULTS: Of the 1453 patients, 391 (26.90%) were positive serologically by IgM ELISA. Seropositive and seronegative patients revealed no significant difference in clinical features and laboratory parameters. Amongst the IgM seropositive cases, culture for leptospires was positive in 5 of 192 (2.6%), MAT in 50 of 138 (36.23%), PCR from blood and urine in 10 of 115 (8.7%) and 10 of 38 (26.31%) cases, respectively. In Leptospira spp. positive patients co-infections with viral hepatitis E, malaria and dengue fever were diagnosed in 27 cases. INTERPRETATION & CONCLUSIONS: The overall seropositivity for leptospirosis was 26.9 per cent in our study. A decreasing trend in seropositivity was observed in recent years. Co-infections with malaria, dengue, hepatitis A and E were also seen. Since leptospirosis is a treatable disease, correct and rapid diagnosis may help in effective management of patients.

Neonatal sepsis in rural India: timing, microbiology and antibiotic resistance in a population-based prospective study in the community setting.

OBJECTIVE: To examine the timing and microbiology of neonatal sepsis in a population-based surveillance in the Indian community setting. STUDY DESIGN: All live born infants in 223 villages of Odisha state were followed at home for 60 days. Suspect sepsis cases were referred to study hospitals for further evaluation including blood culture. RESULTS: Of 12 622 births, 842 were admitted with suspected sepsis of whom 95% were 4 to 60 days old. Culture-confirmed incidence of sepsis was 6.7/1000 births with 51% Gram negatives (Klebsiella predominating) and 26% Gram positives (mostly Staphylococcus aureus). A very high level of resistance to penicillin and ampicillin, moderate resistance to cephalosporins and extremely low resistance to Gentamicin and Amikacin was observed. CONCLUSION: The bacterial burden of sepsis in the Indian community is not high. Judicious choice of empiric antibiotics, antibiotic stewardship and alternate modalities should be considered for the management or prevention of neonatal sepsis in India.

Role of molecular typing in an outbreak of Salmonella paratyphi A.

During the post monsoon season of 1996 an outbreak of human Salmonellosis caused by Salmonella serovar-paratyphi A occurred in New Delhi and had continued for over 2 months. A total of 36 clinically diagnosed enteric-fever cases were reported during this outbreak. The isolates were compared following their characterisation by biotyping, antibiogram-analysis, plasmid-profiling and IS200 probing, to study the relatedness in order to delineate a common source. The study included representative strains from both outbreak (15) and sporadic (7) cases for comparative analysis. Biotyping, antibiogram, whole cell protein-analysis and plasmid-profiling could not discriminate sporadic cases from outbreak strains, suggesting that a single clone/type (PT-1) may be prevalent in our region. In contrast, molecular-typing using IS200-probing revealed 2 clonally related strains circulating during the outbreak, as compared to the unrelated sporadic strains which exhibited considerable genetic diversity. Molecular analysis by IS200-probing, helped to assign an index case which provided a history of later outbreaks, since paratyphi A was repeatedly cultured in later outbreaks also. The study also suggests that genetic rearrangements can occur during the emergence of outbreaks. It reaffirmed the usefulness of IS200-probing in epidemiological investigations of Salmonella enterica serovars.

Drug-resistant Salmonella enterica serotype paratyphi A in India.

The incidence of enteric fever caused by Salmonella enterica serotype Paratyphi A has been increasing in India since 1996. In 1998, the incidence of enteric fever caused by drug- resistant S. Paratyphi A abruptly increased in the New Delhi region. In the first 6 months of 1999, 32% of isolates were resistant to both chloramphenicol and cotrimoxazole and another 13% were resistant to more than two antibiotics.