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Basudha Khanal

Publications and source records attributed to Basudha Khanal.

11 recordsLinked to original sources

Epidemiological dynamics of antimonial resistance in Leishmania donovani: genotyping reveals a polyclonal population structure among naturally-resistant clinical isolates from Nepal.

Pentavalent antimonials (SbV) are the first line drug against leishmaniasis worldwide, but drug resistance is increasingly reported, particularly in the Indian sub-continent, where it represents a major threat for the control of anthroponotic visceral leishmaniasis (VL). In order to understand the epidemiological dynamics of antimonial resistance in anthroponotic VL, we analysed here the population structure of 24 Leishmania donovani stocks isolated from anthroponotic VL-patients from Eastern Nepal: 13 SbV-naturally resistant and 11 SbV-sensitive, as demonstrated by in vitro drug susceptibility assays. The parasites were genotyped by PCR-RFLP analysis of kDNA minicircles and by microsatellite analysis and the encountered polymorphism revealed a polyclonal structure among resistant isolates. Furthermore, analysis of paired samples obtained from the same patients before treatment and after failure revealed primary as well as acquired resistance. The hypothesis of independent events of drug resistance emergence is proposed and confronted to alternative explanations. Our results show the dynamics of drug resistance epidemiology and highlight the importance of surveillance networks.

Amphotericin B↗

Tinea capitis in eastern Nepal.

BACKGROUND: Tinea capitis is an increasing public health concern throughout the world. The clinical types and etiological agents vary from time to time and place to place. This study was undertaken to identify the etiological agents and to determine the clinico-etiological correlation of tinea capitis in eastern Nepal. METHODS: Sixty-nine clinically diagnosed cases of tinea capitis were enrolled in this study. Hair roots and skin scrapings were collected from each patient and subjected to microscopy and culture for identification of fungal hyphae and spores. RESULTS: Tinea capitis accounted for 4.6% of all dermatophyte infections: 68.1% occurred in patients below the age of 11 years with a male to female ratio of 1 : 1.9. "Gray patch" was the most common clinical type (52.2%), followed by "black dot" (17.4%), seborrhoeic dermatitis (13%), alopecia areata (11.6%) and pustular (4.3%). Direct microscopy of hair was positive in 62.3% of patients. Culture positivity was found in 56.7% of patients. Common isolated organisms were Trichophyton violaceum (48.71%), T. mentagrophytes (15.38%), T. tonsurans (12.82%), Microsporum canis (7.69%), T. rubrum and M. gypseum (5.12% each), and M. audouinii and M. nanum (2.56% each). CONCLUSIONS: Trichophyton violaceum was the most common pathogen of tinea capitis. The clinical manifestations were variable and "gray patch" was the most common clinical presentation in this part of the world.

Adolescent↗

Aureobasidium pullulans keratitis.

BACKGROUND: Corneal ulcer caused by Aureobasidium pullulans is considered to be a rare entity. So far very few reports have appeared in the world literature and the authors' hospital is the first to report from Nepal. Although A. pullulans is regarded as a contaminant, it should be considered as a pathogen if isolated from corneal ulcer specimen with clinical signs of infection and with growth of the organism on two or more culture media or growth in one medium with consistent direct microscopy findings or growth of the same organism on repeated corneal scrapings. In the present study, a series of proven cases of A. pullulans corneal ulcers at a tertiary eye care centre of Eastern Nepal is reported. METHODS: A retrospective analysis of stored data of microbiological and clinical cases of corneal ulcer was carried out. All consecutive patients (447 patients) with presumed microbial keratitis from 1 August 1998 to 31 July 2001 were evaluated with regards to clinical details, microbiological examination and management. RESULTS: Of 200 fungal organisms isolated from the cultures, 25 were identified as A. pullulans. These ulcers showed negligible improvement to topical natamycin and required either topical fluconazole or topical itraconazole in all along with systemic intravenous fluconazole in eight patients. Of 25 eyes, 22 responded well to antifungal therapy and 2 required therapeutic penetrating keratoplasty. One patient was lost to follow up for 3 months and revealed phthisis bulbi on subsequent examination. CONCLUSIONS: Aureobasidium pullulans corneal infection should be considered as a cause of keratomycosis.

Ascomycota↗

Clinico-laboratory profile and outcome of Japanese encephalitis in Nepali children.

BACKGROUND: Japanese encephalitis (JE) is associated with high mortality and neurological sequelae. The unpredictable course and lack of specific treatment pose major challenges in management. The tropical climate and paddy ecosystem in Nepal provide a suitable setting. AIMS: To determine the aetiology of febrile encephalopathy and describe the clinico-laboratory profile and outcome of JE in Nepali children. METHODS: A hospital-based prospective and observational study was conducted over a 1-year period (2000-2001). Children aged from >1 month to 14 years with fever >38 degrees C for <2 weeks and altered sensorium were recruited. JE was confirmed by anti-JE IgM in cerebrospinal fluid and/or serum. RESULTS: Of 117 consecutively enrolled patients, 58 had JE. Ten patients had concomitant infections, four with malaria and six with bacterial meningitis, and were excluded from analysis. Clinical findings were as follows: boys, 69%; age 4-14 years, 71%; presentation during summer and autumn, 83%; fever >3 days, 69%; altered sensorium <2 days, 50%; Glasgow coma score 8-12, 63%; seizures, 58%. Four (8.3%) died. At discharge, neurological sequelae were detected in 24 (50%) and hemiparesis was the most common form. Longer duration of vomiting, altered sensorium and focal neurological deficit on admission were independently associated with sequelae at discharge. Sequelae persisted in nine (18.8%) at 6 weeks follow-up. Long duration of altered sensorium (beta co-efficient 0.35, odds ratio 1.4, p=0.042) and presence of focal neurological deficit on admission (beta co-efficient 1.6, odds ratio 5.2, p=0.049) were independent predictors of sequelae at 6 weeks. CONCLUSION: JE was the commonest cause of febrile encephalopathy. Neurological sequelae were common but resolved in two-thirds of cases.

Adolescent↗

Melioidosis imported into Nepal.

This is a report of the first recognized case of melioidosis in Nepal. Illness began 1 month after returning from Malaysia after a 1 y stay. The case highlights the importance of ascertaining the travel history in any patient with a suspected infectious disease in this age of global travel.

Adult↗

Gene expression analysis of the mechanism of natural Sb(V) resistance in Leishmania donovani isolates from Nepal.

Control of visceral leishmaniasis (VL) is being challenged by the emergence of natural resistance against the first line of treatment, pentavalent antimonials [Sb(V)]. An insight into the mechanism of natural Sb(V) resistance is required for the development of efficient strategies to monitor the emergence and spreading of Sb(V) resistance in countries where VL is endemic. In this work, we have focused on the mechanism of natural Sb(V) resistance emerging in Nepal, a site where anthroponotic VL is endemic. Based on the current knowledge of Sb(V) metabolism and of the in vitro trivalent antimonial [Sb(III)] models of resistance to Leishmania spp., we selected nine genes for a comparative transcriptomic study on natural Sb(V)-resistant and -sensitive Leishmania donovani isolates. Differential gene expression patterns were observed for the genes coding for 2-thiol biosynthetic enzymes, gamma-glutamylcysteine synthetase (GCS) and ornithine decarboxylase (ODC), and for the Sb(III) transport protein aquaglyceroporin 1 (AQP1). The results indicate that the mechanism for natural Sb(V) resistance partially differs from the mechanism reported for in vitro Sb(III) resistance. More specifically, we hypothesize that natural Sb(V) resistance results from (i) a changed thiol metabolism, possibly resulting in inhibition of Sb(V) activation in amastigotes, and (ii) decreased uptake of the active drug Sb(III) by amastigotes.

Animals↗

Prevalence of Shigella species and their antimicrobial resistance patterns in Eastern Nepal.

The study was conducted to determine the prevalence of Shigella species and their antimicrobial resistance patterns in eastern Nepal. Stool samples submitted to the diagnostic laboratory of B.P. Koirala Institute of Health Sciences, Nepal, during August 2000-July 2004, were cultured for Shigella species and were confirmed by biochemical and serological tests. Of 53 Shigella species isolated, Shigella dysenteriae type 1 was the most predominant isolate (73.7%), followed by S. flexneri (23%) and S. boydii (4%). The majority (79%) of Shigella species were isolated from children aged less than five years. An overall high resistance was observed for trimethoprim-sulphamethoxazole, ampicillin, nalidixic acid, mecillinam, and ciprofloxacin. There was a statistically significant (p < 0.001) increasing trend in the prevalence of ciprofloxacin resistance in S. dysenteriae type 1. The results suggest reconsideration of the empiric use of these antimicrobial agents for shigellosis. A further study is required to evaluate additional antimicrobial agents.

Adolescent↗

Snakebite-reappraisal of the situation in Eastern Nepal.

Four thousand and seventy eight cases of snakebite, occurring between January and December 2000, were analysed for clinical and epidemiological features. Cases of about 379 had features of envenoming and 81 died. All the victims with systemic envenoming had neurotoxicity. No case with coagulopathy was recorded. Snakebite was more frequent between the ages of 10 and 40 years (76%) and in males (73%). The majority (80%) of the snakebites were observed during the monsoon. Seventy percent of the bites with clinical features of envenoming occurred between 1400 and 2200 h. Five thousand eight hundred and fifty nine vials of polyvalent antisnake venom were used. Case fatality rate varied in the ten centres surveyed. It was as low as 3% in some to as high as 58% in others. Overall death rate among all snakebite cases was 2%.

Adolescent↗

Chromoblastomycosis: report of two cases from Nepal.

Chromoblastomycosis is a chronic fungal infection of the skin and subcutaneous tissue caused by dematiaceous fungi. The first case, a 67-year-old male farmer, presented with itchy hyperkeratotic, scaly plaques with scarring and black dots on the lateral aspects of his left arm and dorsum of his left hand of 28 years duration. The case was clinically diagnosed as chromoblastomycosis. The second case, a 75-year-old farmer, presented with erythematous, crusted, scaly plaques on the dorsum of the left foot of 30 years duration. Initially, a clinical diagnosis of lupus vulgaris was made, but treatment with anti tuberculosis therapy showed no improvement. On the basis of histopathological examinations of skin biopsies and isolation of fungus on culture, both cases were diagnosed as chromoblastomycosis. To the best of our knowledge, these two cases are the first case reports of chromoblastomycosis from Nepal and are presented for their academic interest.

Aged↗