Visceral leishmaniasis

About: Visceral leishmaniasis is a research topic. Over the lifetime, 7486 publications have been published within this topic receiving 184865 citations. The topic is also known as: Kala-Azar & viscus leishmaniasis.

Oral miltefosine treatment in children with mild to moderate Indian visceral leishmaniasis.

Abstract: BACKGROUND: Miltefosine is the first oral drug with demonstrable success in treating visceral leishmaniasis in adults. Because approximately one-half of the visceral leishmaniasis patients worldwide are children, we performed a Phase I/II dose ranging study in the pediatric population in India. METHODS: Thirty-nine (39) children (defined as < 12 years of age) with visceral leishmaniasis demonstrated by parasites in splenic aspirates, were treated with oral miltefosine daily for 28 days: 21 patients received 1.5 mg/kg/day (Group A); and 18 patients received 2.5 mg/kg/day (Group B). About one-half of these children had failed prior antileishmanial treatment. RESULTS: All patients were parasitologically negative and symptomatically improved by the end of therapy on Day 28 of therapy; the initial parasitologic cure rate was 100%. Two patients in each treatment group relapsed with fever, splenomegaly and parasite-positive splenic aspirates by the end of the 6-month follow-up. The per protocol final clinical cure rate was 19 of 21 = 90% in Group A and 15 of 17 = 88% in Group B. Miltefosine was well-tolerated. As per the adult experience, gastrointestinal adverse events were seen: 33 and 39% of children experienced vomiting and 5 and 17% experienced diarrhea in Groups A and B, respectively, but all episodes were mild to moderate in severity and commonly lasted <1 day without symptomatic treatment. CONCLUSION: Oral miltefosine was safe and approximately 90% effective in this initial clinical trial of childhood visceral leishmaniasis.

Genital Lesions Associated with Visceral Leishmaniasis and Shedding of Leishmania sp. in the Semen of Naturally Infected Dogs

Abstract: Although visceral leishmaniasis is primarily transmitted by a biological invertebrate vector, trans- mission in the absence of the vector has been reported, including venereal transmission in humans. Considering the possibility of venereal transmission, we studied genital lesions in dogs naturally infected with visceral leishmaniasis and shedding of Leishmania sp. in the semen. Approximately 200 dogs were serologically tested for anti-Leishmania antibodies and divided into three groups: 1) serologically negative dogs (n 20), 2) asymptomatic serologically positive dogs (n 20), and 3) symptomatic serologically positive dogs (n 20). Samples from both testes, all segments of both epididymes, prostate gland, glans penis, and prepuce were histologically evaluated and processed for immunodetection of Leishmania sp. Semen samples were obtained from 22 symptomatic serologically positive dogs and processed for detecting Leishmania DNA by polymerase chain reaction. A significantly higher frequency of inflammation was observed in the epididymes, glans penis, and prepuce of dogs with visceral leishmaniasis, which was associated with a high frequency of immunohis- tochemically positive tissues (up to 95% of tissues from symptomatic dogs were positive by immunohisto- chemistry). Leishmania DNA was detected in eight of 22 semen samples from symptomatic dogs. Together these findings indicate that genital lesions and shedding of Leishmania sp. (donovani complex) in the semen are associated with visceral leishmaniasis. Additional studies should address the possibility of venereal trans- mission of the disease in the dog.

Rapid, noninvasive diagnosis of visceral leishmaniasis in India: comparison of two immunochromatographic strip tests for detection of anti-K39 antibody.

Abstract: Used with blood or serum, a new anti-K39 antibody immunochromatographic strip test (IT-Leish; DiaMed AG) proved sensitive (range, 99 to 100%) and specific (range, 95 to 100%) for the noninvasive serodiagnosis of visceral leishmaniasis in India. Used with serum, the IT-Leish test and the existing Kalazar Detect test (InBios International, Inc.) yielded comparable results for symptomatic infection and identified apparent subclinical infection in 15 to 32% of healthy residents in a region where visceral leishmaniasis is highly endemic.

Genetic susceptibility to visceral leishmaniasis in The Sudan: linkage and association with IL4 and IFNGR1.

Abstract: Longitudinal studies in Sudan show ethnic differences in incidence and clinical phenotypes associated with Leishmania donovani. Immunologically, bias in type 1 vs type 2 cytokine responses is important. To determine whether polymorphisms at IL4/IL9 or IFNGR1 contribute to susceptibility, we examined 59 multicase families of visceral leishmaniasis (VL) with/without post Kala-azar dermal leishmaniasis (PKDL). Multipoint nonparametric analysis (Allegro) linked IL4/IL9 to VL per se (P=0.002). Transmission disequilibrium testing with robust variance estimates confirmed association in the presence of linkage between VL per se and IL4 (P=0.008) but not IL9. Stepwise logistic regression analysis showed both IL4RP2 and IL4RP1 markers contributed significantly to the association, suggesting a common disease-associated haplotype. In contrast, IFNGR1 was linked (P=0.031) and associated (P=0.007) to PKDL but not VL or VL per se. Hence, polymorphism in a type 2 cytokine gene influences underlying susceptibility to VL, whereas IFNGR1 is specifically related to susceptibility to PKDL.

Risk factors of visceral leishmaniasis in East Africa: a case-control study in Pokot territory of Kenya and Uganda

Abstract: Background In East Africa, visceral leishmaniasis (VL) is endemic in parts of Sudan, Ethiopia, Somalia, Kenya and Uganda. It is caused by Leishmania donovani and transmitted by the sandfly vector Phlebotomus martini. In the Pokot focus, reaching from western Kenya into eastern Uganda, formulation of a prevention strategy has been hindered by the lack of knowledge on VL risk factors as well as by lack of support from health sector donors. The present study was conducted to establish the necessary evidence-base and to stimulate interest in supporting the control of this neglected tropical disease in Uganda and Kenya. Methods A case-control study was carried out from June to December 2006. Cases were recruited at Amudat hospital, Nakapiripirit district, Uganda, after clinical and parasitological confirmation of symptomatic VL infection. Controls were individuals that tested negative using a rK39 antigen-based dipstick, which were recruited at random from the same communities as the cases. Data were analysed using conditional logistic regression. Results Ninty-three cases and 226 controls were recruited into the study. Multivariate analysis identified low socio-economic status and treating livestock with insecticide as risk factors for VL. Sleeping near animals, owning a mosquito net and knowing about VL symptoms were associated with a reduced risk of VL. Conclusions VL affects the poorest of the poor of the Pokot tribe. Distribution of insecticide-treated mosquito nets combined with dissemination of culturally appropriate behaviour-change education is likely to be an effective prevention strategy.