A histological classification of mucocutaneous leishmaniasis in Brazil and its clinical evaluation

Biopsies of skin and mucosal lesions were made on 60 well documented Brazilian patients with untreated cutaneous or mucocutaneous leishmaniasis, whose response to treatment was subsequently evaluated in 38 cases. The biopsies were examined with a view to classification after correlation with clinical and immunological findings. Although there was no simple or unified spectrum, five histological groups were defined and found to have some clinico-prognostic significance. In two groups the cases were all cutaneous with a relatively good prognosis. In another two groups they were evolving as mucocutaneous with a poor prognosis. The fifth group showed mixed characteristics with a tendency to relapse. There was no strong correlation with serum antibodies or Montenegro skin test, which were usually positive, or with parasite load, which was always low. The tissue response was distinguished from that in oriental sore by the degree of connective tissue involvement in all groups. It was the primary response in two groups, and subsidiary to a mono-nuclear response in the others. It suggested damage due to extra-cellular parasites or immune complexes. It did not correlate with the distinction between cutaneous and mucocutaneous disease. The single, most favourable, prognostic feature in either the cellular or connective tissue component was necrosis with a reactive response.

Polymorphism analysis of the internal transcribed spacer and small subunit of ribosomal RNA genes of Leishmania mexicana

Leishmania mexicana causes a wide spectrum of clinical diseases. In spite of the variety of clinical forms, no data exist regarding genetic polymorphism of L. mexicana. We analyzed the polymorphism of the internal transcribed spacer (ITS) and the small subunit rRNA genes of 3 reference strains and 24 Mexican isolates of L. mexicana, by means of polymerase chain reaction and subsequent digestion by restriction enzymes. All strains of L. mexicana had invariant patterns for both the ITS and the small subunit of rRNA genes. Leishmania amazonensis and Leishmania venezuelensis displayed polymorphism only in the ITS. The high degree of identity of this region was confirmed by sequencing DNA from three L. mexicana isolates. There was almost complete identity of the sequence for the ITS region of L. venezuelensis and that of strains of Leishmania major, suggesting that these species may be more closely related than previously thought.

Are New World leishmaniases becoming anthroponoses?

In the New World, leishmaniases are originally wild exoanthropic zoonoses developing in sylvatic ecotopes. For a long time, Leishmania parasites have shown a remarkable plasticity to face modifications in their environment. Now, both geographical extension and numerical increase of leishmaniasis cases in the New World are giving cause for concern. These circumstances might have been provoked by the simple invasion of zoonotic foci by humans. However, dramatic evolutionary mechanisms are also at work in the New World: (i) the reduction of biodiversity associated with anthropogenic environmental changes (deforestation and urbanization); and (ii) the subsequent adaptations and interactions of new vectors and reservoir hosts at the interface with humans. This paper considers that these processes could result in new pathogenic complexes tending to synanthropic zoonoses, if not anthroponoses. Increasing man-made risk factors could thus possibly make leishmaniases a growing public health concern in the New World.

[Cutaneous leishmaniasis: clinical and immunopathological aspects]

Foi visto nesta revisão que os parasitas do gênero Leishmania induzem uma variedade de respostas complexas nos hospedeiros vertebrados, efetuadas e/ou moduladas pelo seu sistema imunológico. Foi também salientado que o destino da Leishmania no interior de macrófagos depende de relações particulares parasito-hospedeiro, envolvendo não apenas as propriedades intrísecas do parasita, mas também as características, geneticamente determinadas, da cédula hospedeira ou das suas interações com outras células imunocompetentes. Atráves de uma revisão das evidências consubstanciando essesconceitos, os mesmos foram aplicados na descrição do espectro clínico e imunopatológico da doença humana, particularmente das leishmanioses cutâneas e mucocutâneas do Novo e do Velho Mundo. Finalmente, baseando-se nos resultados obtidos em modelos experimentais de leishmaniose cutânea, os quais reproduzem os achados das formas resolutiva e persistentes da doença humana, o autor apresenta uma análise esquemática da evolução das características histopatológicas das lesões leishmanióticas.

Estimating human leishmaniasis burden in Spain using the capture-recapture method, 2016-2017

Leishmaniasis is endemic and a mandatory reporting disease in Spain since 1982. However, between 1996 and 2014, surveillance on public health was decentralized and only some autonomous regions monitored the disease. The aim of this study is to estimate the incidence of leishmaniasis and to evaluate the extent of underreporting in Spain. A capture-recapture (CRC) study was conducted to calculate the incidence of human leishmaniasis using reports from the National Surveillance Network (RENAVE) and the Hospital Discharge Records of the National Health System (CMBD) for 2016 and 2017. During the study period, 802 cases were reported to RENAVE and there were 1,149 incident hospitalizations related to leishmaniasis. The estimated incidence rates through the CRC study were 0.79 per 100,000 inhabitants for visceral leishmaniasis (VL), 0.88 (cutaneous leishmaniasis (CL)) and 0.12 (mucocutaneous leishmaniasis (MCL)) in 2016 and 0.86 (VL), 1.04 (CL) and 0.12 (MCL) in 2017. An underreporting of 14.7-20.2% for VL and 50.4-55.1% for CL was found. The CRC method has helped us to assess the sensitivity and representativeness of leishmaniasis surveillance in Spain, being a useful tool to assess whether the generalization of leishmaniasis surveillance throughout the Spanish territory achieves a reduction in underreporting.

Leishmaniasis: early diagnosis is key

A patient presents with nasal congestion, a history of nosebleed, and painful lesions on his body and in his mouth. What questions should you ask to ensure that you make an accurate diagnosis?

[Leishmaniasis and human immunodeficiency virus: an emerging co-infection?]

Although not considered as indicative of AIDS, leishmaniasis presents a number of epidemiologic and clinical features that promote opportunistic infection in HIV patients. Accurate assessment of the incidence of this type of co-infection is difficult due to underestimation in endemic areas such as Africa and Asia. In these areas the WHO estimates that 2 to 9 p. 100 of HIV patients will develop leishmaniasis/HIV co-infection which could become a major concern. The characteristics of this co-infection have been documented. It is observed in adults between 20 and 40 years of age with a strong male sex bias. The visceral form is most frequent. Manifestations are similar to those observed in immunocompetent subjects but with the possibility of asymptomatic and low-grade forms (10 p. 100) and unusual locations suggesting multiorgan spreading in absence of host immune response. In addition to the time-tested standard procedures for diagnosis of parasitic disease, new serologic tests and genomic amplification are now available. Pentavalent antimonials have long been considered as the treatment of choice but they are not always effective and can have untoward effects. Amphotericine B especially in the liposomal form is a good alternative. The particularly high incidence of recurrence suggests that follow-up may be indicated but the modalities of prophylaxis have yet to be defined.

Clinical aspects of leishmaniasis with special reference to the USSR

The wide variety of clinical syndromes produced in man by infection with members of the genus Leishmania has caused a great deal of confusion for many years, and has proved a serious obstacle to the rational classification of the leishmaniases.The situation has been complicated still further by the morphological identity of many species of Leishmania and by the behavioural similarities in vitro and in laboratory animals of species and strains producing distinct clinical or epidemiological patterns in humans. There has been a general failure to use standardized, comparable, and reproducible techniques in experimental studies of the various species of Leishmania; in particular, with one or two notable exceptions, there has been failure to adopt quantitative methods when studying Leishmania and the leishmaniases.This paper therefore attempts to classify the leishmaniases from clinical and epidemiological standpoints, and illustrates the provisional classification adopted with special reference to the situation in the USSR.

[Cutaneous Leishmaniasis in Africa. Classification-clinical picture-treatment]

Vast travelling nowadays into warm subtropical and tropical regions demands more knowledge about infectious diseases outside our temperate climate. A leishmaniasis infection in Europeans is no rarity today because of its vast distribution in Africa. Cutaneous leishmaniasis is now considered a spectral and polar disease not unlike leprosy, caused by the leishmania parasite but also influenced by the host's immune response and intolerance. Therefore, diagnosis and treatment of a cutaneous leishmaniasis request an immunopathohistological view of the case.

Diagnosis & management of leishmania/HIV co-infection

Leishmaniasis, a globally prevalent parasitic disease occurs in three forms viz., visceral, cutaneous and mucocutaneous, transmitted by the bite of infected female Phlebotomus sandflies. Visceral leishmaniasis (VL) has 100 per cent fatality rate, if left untreated. India has the largest burden of this disease. HIV infection is also increasing worldwide and several reports indicate rising trend of VL/ HIV co-infection, modifying the traditional anthroponotic pattern of VL transmission. Both VL and HIV tend to lower the cell mediated immunity (CMI) resulting in poor drug response and opportunistic infections involving gastrointestinal, cutaneous, respiratory tract and central nervous system (CNS) may occur. Diagnosis of such co-infected cases is quite difficult. However, newer tests like nested PCR, rk39 immunochromatographic test etc., can be of help. Response to different antileishmanial drugs like sodium antimony gluconate (SAG), amphotericin B is far from satisfactory. However, a new oral drug miltefosine has been found to be promising. Highly active antiretroviral therapy (HAART) need to be given for management of HIV infection along with treatment of other opportunistic infections.

[Dermatologic problems in travelers returning from the tropics]

The most important dermatological diagnoses reported by 4 clinics in tropical locations are compared with those encountered over a period of 2 years in travellers returning from the tropics and treated in a Swiss medical practice. In both settings infections, parasitic disorders and allergic exanthems predominated. Since it often goes unrecognized, cutaneous leishmaniasis is dealt with in special detail.