Identification of post-kala-azar dermal leishmaniasis (PKDL) is important due to the long and toxic treatment and the fact that PKDL patients may serve as a reservoir for visceral leishmaniasis (VL). We summarized the published literature about the accuracy of diagnostic tests for PKDL. We searched Medline for eligible studies investigating the diagnostic accuracy of any test for PKDL. Study quality was assessed using QUADAS-2. Data were extracted from 21 articles including 43 separate studies. Twenty-seven studies evaluated serological tests (rK39 dipstick, ELISA, DAT, and leishmanin tests), six studies molecular tests, eight microscopy, and two cultures. Only a few of these studies reported a valid estimate of diagnostic accuracy, as most were case-control designs or used a reference standard with low sensitivity. The included studies were very heterogeneous, for example, due to a large variety of reference standards used. Hence, no summary estimates of sensitivity or specificity could be made. We recommend well-designed diagnostic accuracy trials that evaluate, side-by-side, all currently available diagnostics, including clinical symptoms, serological, antigen, molecular, and parasitological tests and possible use of statistical modelling to evaluate diagnostics when there is no suitable gold standard. 1. Introduction Post-kala-azar dermal leishmaniasis (PKDL) is a skin disorder that often appears after treatment for visceral leishmaniasis (VL) patients. It has also been reported in individuals without prior history of VL as well as those undergoing treatment for VL. The protozoan parasite Leishmania donovani is the only causative agent. Clinical manifestations of PKDL are macular, maculopapular, and nodular rash in people who are otherwise well and recovering, although more serious manifestations of facial ulcers can occur. In Sudan approximately 50% of VL patients go on to develop PKDL [1]; but in the Indian subcontinent only 5–10% develop this infection [2]. The clinical presentation of PKDL varies, making diagnosis difficult, especially in those without a history of VL. Accurate diagnosis of PKDL is important due to the long and toxic treatment with antileishmanial drugs. Treatment can last up to 6 months, and the drugs can have serious side-effects for patients and is a waste of medical and economic resources. Therefore, a testing regime with a high specificity is essential to avoid false positive results and hence to avoid waste and unnecessary treatment of patients with toxic drugs. On the other hand, diagnostics for PKDL should also have a
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