Diagnosis of cutaneous leishmaniasis

Abstract

The purpose of this review is to discuss some of the most important issues in the clinical and laboratory diagnosis of cutaneous leishmaniasis. The former is based on clinical experience and the latter on the literature published within the last couple of years. The sensitivity and specificity of old and novel tests to identify the parasite, antigenic products, the host's immune response, and the molecular diagnosis by the PCR are considered here. Recent clinical and laboratory research has addressed the individual, entomological, and epidemiological aspects of acute and chronic forms of cutaneous leishmaniasis. Traditional diagnostic investigations for individual cases include the search of suggestive history and clinical features, the identification of amastigotes by histology or direct microscopy, and the growth of promastigotes in culture. Diagnosis by the polymerase chain reaction seems to be approaching a 'gold standard' status as novel techniques offer considerable advantages in the collection and transport of specimens and DNA extraction procedures that are more efficient in individual and field-based protocols. Several authors have reported consistent 100% specificity with increasing sensitivity that overall is between 92 and 98%. Moreover the PCR approach makes possible the fast identification at the Leishmania species and subspecies level. The diagnostic tools discussed in this review are relevant not only for the diagnosis in endemic regions of the world but also for travellers and workers that following exposure return to non-endemic countries.