Recent advances in post-kala-azar dermal leishmaniasis

Abstract

Post-kala-azar dermal leishmaniasis (PKDL) is a challenge for clinicians and researchers, because its burden is poorly investigated and pathogenesis is disputable. However, recent studies contributed to understanding of the pathogenesis of PKDL especially its association with host immunological factors, and also how to improve its diagnosis and treatment. This review focuses on recent advances in diagnosis, new insights into pathogenesis and case management. Information regarding the burden of PKDL, especially in Bangladesh, is now available. Association between skin parasite burden and different clinical forms of PKDL has been explored. The diagnostic importance of detection of Leishmania donovani DNA in the peripheral blood buffy coat and in skin specimens by PCR has been studied. Variable effects of different antileishmanial drugs on immune response have been observed. Finally, high efficacy of miltefosine for treatment of PKDL has been demonstrated. The incidence of PKDL is reducing in India after introduction of miltefosine and amphotericin B for treatment of visceral leishmaniasis. It remains higher in Bangladesh and in Sudan. Parasite burden is higher in nodular and papular forms of PKDL compared to the macular form of the disease. The demonstration of Leishmania DNA in peripheral blood buffy coat and in skin specimens can help to diagnose 40-75% clinically suspected PKDL individuals. An initial cure rate of 95% has been achieved with miltefosine for treatment of PKDL. However, the efficacy of combination therapy should be explored to reduce the treatment duration and hence to improve treatment compliance.