The utility of multiplex polymerase chain reaction for diagnosis of infectious diarrhoea in a tropical country.

PURPOSE: The etiology of infective diarrheaoften remains undiagnosed. We studied the role of multiplex polymerase chain reaction (PCR) for detection of etiological agents of diarrhoea. METHODS: Fast track diagnostics (FTD)gastroenteritis panel for bacterial and viral pathogens was used to test stool samples from patients with diarrhoea. RESULTS: Stool samples from 276 patients (138 immunocompetent and 138 immunocompromised) with diarrhoea and 138 healthy controls were tested. Bacterial culture was positive in 5 samples. Following agents were isolated: Shigella sonnei(2), Shigella dysentriae(1), SalmonellaParatyphi B(1) and Vibrio cholerae (1). Multiplex PCR panel did not include Vibrio cholerae in its panel. A total of 65 target pathogens were identified in 60/276 (21.7%) patients by multiplex PCR. 28/65(41.1%) and 37/65 (56.9%) were bacterial and viral agents respectively. Identified bacteria were Shigella(20), Salmonella(3), Campylobacter(4) and Clostridium difficile(1). Viral targets identified were Norovirus GII (28), Adenovirus(4), Astrovirus(3) and Sapovirus(2). All the controls were negative for enteropathogens by conventional methods and multiplex PCR. CONCLUSIONS: Our detection rates increased from 1.8% (5/276)by conventional methods to 21.7% (60/276)by multiplex PCR, which included both bacterial as well as viral targets.

Asymptomatic filariasis and leprosy co-morbidity in a patient with suspected Guillain-Barrè syndrome: the first case report of an incidental finding in a slit-skin smear.

INTRODUCTION: Lymphatic filariasis (LF) and leprosy are both endemic in India. These diseases are on the World Health Organization (WHO) list of neglected tropical diseases (NTDs), as they affect the most marginalized communities in the world, resulting in deformities and functional limitation. We report the first case of asymptomatic filariasis and leprosy co-morbidity in a patient with suspected Guillain-Barré syndrome. CASE PRESENTATION: A 55-year-old male who was a farmer by occupation presented to the Neurology Outpatient Department (OPD) of our institute with complaints of weakness in all four limbs for the last 15 days. After admission, a detailed history revealed that the patient had been taking multi-drug therapy (MDT) for leprosy for the previous 6 months. After symptomatic management of the presenting complaints, the patient was sent to the Department of Microbiology for a consultation and six-site slit-skin sampling. The initial screening of Ziehl-Neelsen (ZN)-stained smears under a 10× objective led to the incidental finding of sheathed structures resembling microfilaria (Mf) on the smear made from ear lobules. In addition, short acid-fast bacilli (AFB) were also observed under the oil-immersion objective. CONCLUSION: We emphasize that a high index of suspicion and thorough screening of smears by a microbiologist is essential in specimens obtained from any body site.