Dermonodular and visceral leishmaniasis due to Leishmania infantum with a new isoenzyme pattern: report of a case involving a patient with AIDS

The Leishmania donovani species complex: A new insight into taxonomy☆

Among the 20 or so Leishmania spp. described as pathogenic for humans, those of the Leishmania donovani complex are the exclusive causative agents of systemic and fatal visceral leishmaniasis. Although well studied, the complex is taxonomically controversial, which hampers clinical and epidemiological research. In this work, we analysed 56 Leishmania strains previously identified as L. donovani, Leishmania archibaldi or Leishmania infantum, isolated from humans, dogs and sandfly vectors throughout their distribution area. The strains were submitted to biochemical and genetic analyses and the resulting data were compared for congruence. Our results show: i) a partial concordance between biochemical and genetic-based data, ii) very limited genetic variability within the L. donovani complex, iii) footprints of frequent genetic exchange along an east-west gradient, marked by a widespread diffusion of alleles across the geographical range, and iv) a large-scale geographical spreading of a few genotypes. From a taxonomic point of view, considering the absence of relevant terminology in existing classes, the L. donovani complex could be treated as a single entity.

Analysis of genetic polymorphisms and tropism in East African Leishmania donovani by Amplified Fragment Length Polymorphism and kDNA minicircle sequencing

Visceral leishmaniasis (VL), the most severe form of leishmaniasis, is caused by Leishmania donovani. In addition to fatal VL, these parasites also cause skin diseases in immune-competent and -suppressed people, post-kala azar dermal leishmaniasis (PKDL) and HIV/VL co-infections, respectively. Genetic polymorphism in 36 Ethiopian and Sudanese L. donovani strains from VL, PKDL and HIV/VL patients was examined using Amplified Fragment Length Polymorphism (AFLP), kDNA minicircle sequencing and Southern blotting. Strains were isolated from different patient tissues: in VL from lymph node, spleen or bone marrow; and in HIV/VL from skin, spleen or bone marrow. When VL and PKDL strains from the same region in Sudan were examined by Southern blotting using a DNA probe to the L. donovani 28S rRNA gene only minor differences were observed. kDNA sequence analysis distributed the strains in no particular order among four clusters (A - D), while AFLP analysis grouped the strains according to geographical origin into two major clades, Southern Ethiopia (SE) and Sudan/Northern Ethiopia (SD/NE). Strains in the latter clade were further divided into subpopulations by zymodeme, geography and year of isolation, but not by clinical symptoms. However, skin isolates showed significantly (p < 0.0001) fewer polymorphic AFLP fragments (average 10 strains = 348.6 ± 8.1) than VL strains (average 26 strains = 383.5 ± 3.8).

PKDL and other dermal lesions in HIV co-infected patients with Leishmaniasis: review of clinical presentation in relation to immune responses

Background

Co-infection of leishmaniasis and HIV is increasingly reported. The clinical presentation of leishmaniasis is determined by the host immune response to the parasite; as a consequence, this presentation will be influenced by HIV-induced immunosuppression. As leishmaniasis commonly affects the skin, increasing immunosuppression changes the clinical presentation, such as in post-kala-azar dermal leishmaniasis (PKDL) and cutaneous leishmaniasis (CL); dermal lesions are also commonly reported in visceral leishmaniasis (VL) and HIV co-infection.

Methods

We reviewed the literature with regard to dermal manifestations in leishmaniasis and HIV co-infection, in three clinical syndromes, according to the primary presentation: PKDL, VL, or CL.

Results

A wide variety of descriptions of dermal leishmaniasis in HIV co-infection has been reported. Lesions are commonly described as florid, symmetrical, non-ulcerating, nodular lesions with atypical distribution and numerous parasites. Pre-existing, unrelated dermal lesions may become parasitized. Parasites lose their tropism and no longer exclusively cause VL or CL. PKDL in HIV co-infected patients is more common and more severe and is not restricted to Leishmania donovani. In VL, dermal lesions occur in up to 18% of patients and may present as (severe) localized cutaneous leishmaniasis, disseminated cutaneous leishmaniasis (DL) or diffuse cutaneous leishmaniasis (DCL); there may be an overlap with para-kala-azar dermal leishmaniasis. In CL, dissemination in the skin may occur resembling DL or DCL; subsequent spread to the viscera may follow. Mucosal lesions are commonly found in VL or CL and HIV co-infection. Classical mucocutaneous leishmaniasis is more severe. Immune reconstitution disease (IRD) is uncommon in HIV co-infected patients with leishmaniasis on antiretroviral treatment (ART).

Conclusion

With increasing immunosuppression, the clinical syndromes of CL, VL, and PKDL become more severe and may overlap. These syndromes may be best described as VL with disseminated cutaneous lesions (before, during, or after VL) and disseminated cutaneous leishmaniasis with or without visceralization.

Cutaneous Infections Associated with HIV/AIDS

With diminished and dysregulated cell-mediated immunity, HIV-infected individuals are susceptible to a myriad of skin infections. These infections include the conditions encountered in immunocompetent patients, as well as infections seen almost exclusively in the setting of HIV infection. The HIV/AIDS pandemic has made some previously rare infections more prominent. Although antiretroviral therapy has been helpful in relieving the burden of cutaneous infections in HIV-infected patients, it does not prevent all opportunistic infections in the skin and also has created new dilemmas.

Presence of Leishmania organisms in specific and non-specific skin lesions in HIV-infected individuals with visceral leishmaniasis

BACKGROUND

Leishmania coinfection is frequently seen in human immunodeficiency virus (HIV)-infected patients in endemic areas, and from time to time the protozoan is detected in cutaneous biopsies.

OBJECTIVE

To establish the characteristics and possible ethiologic role of the presence of Leishmania in these lesions.

METHODS

We studied 12 cutaneous biopsies with Leishmania organisms from nine HIV-infected patients (seven men and two women) with visceral leishmaniasis, diagnosed by bone marrow examination, seen over a period of 9 years.

RESULTS

Based on clinical characteristics, evolution and response to anti-leishmanial treatment, cutaneous alterations were found to be related to the presence of the protozoan in six cases, whereas in the other six cases it was not considered responsible for the dermatological lesions (dermatofibroma, and lesions of psoriasis, Reiter's syndrome, bacillary angiomatosis, cryptococcosis and oral aphthae). Of note was the high prevalence of specific mucocutaneous manifestations, usually accompanied by intense pruritus, great variability, and a tendency to relapse after treatment stopped. On two occasions, detection of the protozoa in skin biopsies led to the diagnosis of a previously unsuspected visceral leishmaniasis.

CONCLUSIONS

Cutaneous detection of Leishmania is frequent in HIV-infected individuals with visceral leishmaniasis. Sometimes Leishmania is associated with changes attributable to other dermatological processes, and its presence does not imply a causative role. A clear relationship between the systemic process and the therapeutic response is necessary to demonstrate an ethiologic role.

Kaposi's sarcoma-like lesions and other nodules as cutaneous involvement in AIDS-related visceral leishmaniasis

A 40-year-old human immunodeficiency virus (HIV)-positive man had three relapses of visceral leishmaniasis (VL). In the third he developed nodular skin lesions of three types, some reminiscent of Kaposi's sarcoma. Biopsy of each type disclosed abundant dermal macrophages with a huge number of intracellular and extracellular Leishman-Donovan bodies. Rapid improvement of lesions was achieved after antiparasitic treatment. AIDS leads to atypical forms of leishmaniasis. Leishmania has been detected both in normal and pathological skin of these patients due to dissemination during VL. It is suspected that a considerable proportion of the population may be infected in endemic areas, Leishmania being opportunistic in immunosuppressed individuals. It is important to recognize the range of lesions that may occur in patients with HIV and VL, many of which are non-specific and may cause diagnostic difficulty.

Unusual cutaneous lesions in two patients with visceral leishmaniasis and HIV infection

Two HIV infected patients with visceral leishmaniasis and unusual cutaneous lesions are described. The first patient developed linear brown macules containing Leishmania parasites on the fingers and palms of the hands. This patient never received highly active antiretroviral treatment and the visceral leishmaniasis could not be cured even with liposomal amphotericin. In the second patient, Leishmania parasites were present in a skin biopsy of a fibrous histiocytoma. After completing visceral leishmaniasis treatment, a discrete elevation of one of his tattoos was seen. A biopsy specimen of this tattoo revealed Leishmania amastigotes. In this patient the visceral leishmaniasis was finally cured with meglumine antimoniate, followed by pentacarinat isothianate as maintenance therapy in conjunction with highly active antiretroviral treatment.

Visceral leishmaniasis with cutaneous lesions in a patient infected with human immunodeficiency virus

We report a case of visceral leishmaniasis (VL) with cutaneous lesions in a patient infected with human immunodeficiency virus (HIV). The cutaneous lesions consisted of erythematous papules on the legs. Biopsy of one lesion showed abundant Leishmania amastigotes within epithelial cells of an eccrine sweat gland in the dermis. Leishmania organisms were also found in a blood smear. Rapid and complete clearance of the cutaneous lesions was achieved after antimony therapy. Cutaneous lesions in VL are being reported increasingly frequently in patients with HIV infection and their significance remains in discussion.

Mediterranean leishmaniasis in HIV-infected patients: epidemiological, clinical, and diagnostic features of 22 cases

Twenty-two Italian HIV-infected patients developed leishmaniasis, clinically manifested as visceral (13 cases), cutaneous (2 cases) and disseminated disease (7 cases). Twenty were males and two females (mean age: 32.8 years) with a mean CD4+ cell count of 46.8/microliter at diagnosis; risk factors were intravenous drug use (17 patients) and sexual behaviour (two bisexual, two homosexual, one heterosexual). All but one patient lived or travelled in hypoendemic Italian regions and other Mediterranean countries. Apart from the two patients with cutaneous leishmaniasis, the clinico-pathological and biological spectrum of the infection was often atypical, especially in patients with disseminated disease. The diagnosis was routinely made by direct recovery of parasites in biological specimens, mainly in bone marrow aspirate, whereas serology was negative or borderline in most of the patients. Among 17 in vitro isolates, Leishmania infantum was the only species involved with previously undescribed isoenzyme patterns in two cases. Treatment with antimonials and other drugs showed only temporary clinical improvement in some patients. Relapses were the rule. Leishmaniasis confirms itself as an opportunistic infection in HIV-positive persons. Secondary chemoprophylaxis should be considered in cases of relapsing disease.

Leishmania and human immunodeficiency virus coinfection: the first 10 years

Over 850 Leishmania-human immunodeficiency virus (HIV) coinfection cases have been recorded, the majority in Europe, where 7 to 17% of HIV-positive individuals with fever have amastigotes, suggesting that Leishmania-infected individuals without symptoms will express symptoms of leishmaniasis if they become immunosuppressed. However, there are indirect reasons and statistical data demonstrating that intravenous drug addiction plays a specific role in Leishmania infantum transmission: an anthroponotic cycle complementary to the zoonotic one has been suggested. Due to anergy in patients with coinfection, L. infantum dermotropic zymodemes are isolated from patient viscera and a higher L. infantum phenotypic variability is seen. Moreover, insect trypanosomatids that are currently considered nonpathogenic have been isolated from coinfected patients. HIV infection and Leishmania infection each induce important analogous immunological changes whose effects are multiplied if they occur concomitantly, such as a Th1-to-Th2 response switch; however, the consequences of the viral infection predominate. In fact, a large proportion of coinfected patients have no detectable anti-Leishmania antibodies. The microorganisms share target cells, and it has been demonstrated in vitro how L. infantum induces the expression of latent HIV-1. Bone marrow culture is the most useful diagnostic technique, but it is invasive. Blood smears and culture are good alternatives. PCR, xenodiagnosis, and circulating-antigen detection are available only in specialized laboratories. The relationship with low levels of CD4+ cells conditions the clinical presentation and evolution of disease. Most patients have visceral leishmaniasis, but asymptomatic, cutaneous, mucocutaneous, diffuse cutaneous, and post-kala-azar dermal leishmaniasis can be produced by L. infantum. The digestive and respiratory tracts are frequently parasitized. The course of coinfection is marked by a high relapse rate. There is a lack of randomized prospective treatment trials; therefore, coinfected patients are treated by conventional regimens. Prophylactic therapy is suggested to be helpful in preventing relapses.