A comprehensive literature search of medical databases (Medline and Cochrane library) and non-medical search engines was done using several keywords: “leishmaniasis”, “leishmaniosis”, “leishmania”, “cutaneous”, “mucosal”, “mucocutaneous”, and “diffuse”. We paid particular attention to articles published in the non-English literature, as these have had little exposure in previous reviews. If appropriate, we contributed our personal knowledge on the subject. Our review focused on studies
ReviewCutaneous leishmaniasis
Introduction
Leishmania parasites are the causal agents of leishmaniasis, a group of protozoan diseases transmitted to mammals, including human beings, by phlebotomine sandflies. Globally, there are an estimated 1·5–2 million new cases and 70 000 deaths each year, and 350 million people are at risk of infection and disease.1 Morbidity and mortality because of the leishmaniases cause an estimated 2·4 million disability-adjusted life-years.1
The leishmaniases are characterised by a spectrum of clinical manifestations: ulcerative skin lesions developing at the site of the sandfly bite (localised cutaneous leishmaniasis [LCL]); multiple non-ulcerative nodules (diffuse cutaneous leishmaniasis [DCL]); destructive mucosal inflammation (mucosal leishmaniasis); and disseminated visceral infection (visceral leishmaniasis). The clinical spectrum observed in patients indicates the complexity of leishmaniasis epizoology: several Leishmania spp can cause disease (table 1), and many sandfly and mammalian species have been implicated as vectors and reservoir hosts, respectively.
We critically review the most recent data on the burden of the cutaneous leishmaniases, namely LCL, DCL, and mucosal leishmaniasis, their epidemiology, clinical pathology, diagnosis, treatment, prevention, and control. Visceral leishmaniasis has been reviewed elsewhere;2, 3, 4 we did not review post kala-azar dermal leishmaniasis, because this is a manifestation seen in patients with visceral leishmaniasis after apparent clinical cure.
Section snippets
Disease burden and distribution
Cutaneous leishmaniasis is endemic in more than 70 countries worldwide, and 90% of cases occur in Afghanistan, Algeria, Brazil, Pakistan, Peru, Saudi Arabia, and Syria (figure 1).5 Surveillance data indicate that the global number of cases has increased during the past decade, as documented in Afghanistan,6 Bolivia,7 Brazil,8 Colombia,7, 9 Peru,7 and Syria.10 Such increases can be explained in part by improved diagnosis and case notification,11 but are also a result of inadequate vector or
Clinical symptoms
Several Leishmania spp can cause cutaneous leishmaniasis in human beings, although most infections probably remain symptomless.2 The first sign of an infection is typically a small erythema that develops after a variable prepatent period at the site where an infected sandfly has bitten the host. The erythema develops into a papule, then a nodule that progressively ulcerates over a period of 2 weeks to 6 months to become the lesion that is characteristic of LCL.35 LCL lesions vary in severity
Diagnosis
The broad clinical spectrum of cutaneous leishmaniasis makes diagnosis of present and past cases difficult. Differential diagnosis is important because diseases of other causes but with a similar clinical spectrum to leishmaniasis (eg, leprosy, skin cancers, tuberculosis, cutaneous mycoses) are common in leishmaniasis-endemic areas.14
Parasitological diagnosis remains the gold standard in cutaneous leishmaniasis diagnosis, because of its high specificity. It includes microscopic examination of
Vector and reservoir control
Because the strategies available are expensive and labour intensive, and because cutaneous leishmaniasis is a non-fatal disease, prevention and control strategies have mainly focused on treatment of the human disease, rather than on the elimination of reservoirs or reduction of human–vector contact.162 Hence, most approaches have been limited to pilot research studies and only a few have been brought up to operational scale.163
Sandflies are highly susceptible to insecticides. Although they
Conclusions
The leishmaniases are a complex group of diseases and although we know much more than we did a decade ago, we are no nearer to the prevention or control of this neglected disease, which mainly affects the world's poorest populations.183 To do so requires professional and financial commitment, focusing on key research and policy areas (panel). Over the past decade, several reviews and reports have identified priorities in research and public-health policy with regard to cutaneous leishmaniasis.
Search strategy and selection criteria
References (183)
- et al.
Advances in leishmaniasis
Lancet
(2005) - et al.
Treatment options for visceral leishmaniasis: a systematic review of clinical studies done in India, 1980–2004
Lancet Infect Dis
(2005) - et al.
Visceral leishmaniasis: current status of control, diagnosis, and treatment, and a proposed research and development agenda
Lancet Infect Dis
(2002) - et al.
Epidemiological surveys confirm an increasing burden of cutaneous leishmaniasis in north-east Brazil
Trans R Soc Trop Med Hyg
(1999) - et al.
Twenty years of cutaneous leishmaniasis in Aleppo, Syria
Trans R Soc Trop Med Hyg
(1997) The increase in risk factors for leishmaniasis worldwide
Trans R Soc Trop Med Hyg
(2001)The biology and control of phlebotomine sandflies
Clin Dermatol
(1999)Leishmaniasis reservoirs and their significance in control
Clin Dermatol
(1996)- et al.
Topical treatment of Old World cutaneous leishmaniasis caused by Leishmania major: a double-blind control study
J Am Acad Dermatol
(1992) - et al.
Non-ulcerative cutaneous leishmaniasis in Honduras fails to respond to topical paromomycin
Trans R Soc Trop Med Hyg
(1997)