A clinico-pathological study of cutaneous leishmaniasis in British troops from Belize

Characterisation of an area of coexistent visceral and cutaneous leishmaniasis transmission in the State of Piauí, Brazil

BACKGROUND

In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area.

OBJECTIVES

This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area.

METHODS

In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors.

FINDINGS

The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA.

MAIN CONCLUSION

Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.

Cutaneous and mucocutaneous leishmaniasis: Differential diagnosis, diagnosis, histopathology, and management

The diagnosis of leishmaniasis can be challenging because it mimics both infectious and malignant conditions. A misdiagnosis may lead to an unfavorable outcome. Using culture, histologic, and/or polymerase chain reaction study results, a diagnosis of leishmaniasis can be established and treatment initiated. Appropriate management requires an accurate diagnosis, which often includes identification of the specific etiologic species. Different endemic areas have varying sensitivities to the same medication, even within individual species. Species identification may be of practical value, because infections with select species have a substantial risk of visceral involvement. In addition, HIV and otherwise immunocompromised patients with leishmaniasis have a propensity for diffuse cutaneous leishmaniasis. For most New World Leishmania species, parenteral antimonial drugs remain the first line of therapy, while Old World species are easily treated with physical modalities. Historically, live organism vaccination has been used and is effective in preventing leishmaniasis, but results in an inoculation scar and an incubation period that may last for years. A more effective method of vaccination would be welcome.

Panniculitis is an important feature of cutaneous leishmaniasis pathology

Background. Cutaneous leishmaniasis is an inflammatory parasitic infection characterized by superficial and deep perivascular infiltration with or without granuloma formation. Clinical diagnosis usually requires seeing Leishmania bodies. Methods. We report two cases of cutaneous leishmaniasis with unusual histological finding of panniculitis. Case 1: a 36-year-old male presented with multiple ulcerative nodules involving the left leg for two months duration which was greatly responsive to antimony intralesional therapy. Case 2: A 45-year-old woman presented with painless nodules on her upper chest of a 10-week duration which were successfully treated with oral and topical zinc sulphate. Results. Diagnosis of both cases was confirmed by finding the Leishmania bodies with Gimesa stain in addition to the diffuse dermal inflammatory cellular infiltration of the dermis forming granulomatous dermatitis. Mixed cellular infiltration of lymphocytes, histiocytes, and plasma cells of the panniculus caused both septal and lobular panniculitis. Conclusion. Cutaneous leishmaniasis can cause panniculitis and this could be seen more commonly if deep biopsies were taken. So cutaneous leishmaniasis must be considered in evaluating pathology of panniculitis especially in endemic regions.

Infection-induced respiratory burst in BALB/c macrophages kills Leishmania guyanensis amastigotes through apoptosis: possible involvement in resistance to cutaneous leishmaniasis

The immune mechanisms that underlie resistance and susceptibility to leishmaniasis are not completely understood for all species of Leishmania. It is becoming clear that the immune response, the parasite elimination by the host and, as a result, the outcome of the disease depend both on the host and on the species of the infecting Leishmania. Here, we analyzed the outcome of the infection of BALB/c mice with L. guyanensis in vivo and in vitro. We showed that BALB/c mice, which are a prototype of susceptible host for most species of Leishmania, dying from these infections, develop insignificant or no cutaneous lesions and eliminate the parasite when infected with promastigotes of L. guyanensis. In vitro, we found that thioglycollate-elicited BALB/c peritoneal macrophages, which are unable to eliminate L. amazonensis without previous activation with cytokines or lipopolysaccharide, can kill L. guyanensis amastigotes. This is the first report showing that infection of peritoneal macrophages with stationary phase promastigotes efficiently triggers innate microbicidal mechanisms that are effective in eliminating the amastigotes, without exogenous activation. We demonstrated that L. guyanensis amastigotes die inside the macrophages through an apoptotic process that is independent of nitric oxide and is mediated by reactive oxygen intermediates generated in the host cell during infection. This innate killing mechanism of macrophages may account for the resistance of BALB/c mice to infection by L. guyanensis.

Cutaneous leishmaniasis: current and future management

Leishmaniasis remains a major world health problem that continues to increase in incidence. This review considers epidemiology, clinical features, diagnosis and current treatment options. Recent developments in the treatment of simple cutaneous leishmaniasis are discussed followed by speculation about future therapies.

The management of cutaneous leishmaniasis from Belize

We report 20 patients who contracted cutaneous leishmaniasis in Central and South America, 18 of them in Belize. The diagnosis was confirmed by the polymerase chain reaction (PCR) in 79% of those tested; the corresponding figure for histology was 62%, touch smear 46%, and culture 11%. Results of PCR can be falsely positive, so treatment should not be based on PCR alone. Of the 20 cases 18 were healed 6 weeks after intravenous sodium stibogluconate 20 mg/kg per day for 20 days. We present a management protocol.

Cutaneous leishmaniasis

Leishmaniasis is a major World health problem, which is increasing in incidence. In Northern Europe it is seen in travellers returning from endemic areas. The protozoa is transmitted by sandflies and may produce a variety of clinical syndromes varying from a simple ulcer to fatal systemic disease. This review considers the management of simple cutaneous leishmaniasis. Patients usually have a single ulcer which may heal spontaneously, requiring only topical, or no treatment at all. Lesions caused by Leishmania braziliensis may evolve into the mucocutaneous form, 'espundia', and should be treated with systemic antimony. Sodium stiboglucoante 20 mg/kg/day i. v. for 20 days is the appropriate first line treatment in these cases. Although it may cause transient bone marrow suppression, liver damage, a chemical pancreatitis, and disturbances in the electrocardiogram, it appears to be safe. The success of treatment should be assessed 6 weeks after it has been completed and patients should be followed up for 6 months.

New World cutaneous leishmaniasis imported into Australia

A case of cutaneous leishmaniasis in a traveller from Belize, Central America is reported. Leishmaniasis presents rarely in Australia and delays in diagnosis and treatment often occur. A high index of suspicion in a patient who has returned from an endemic region is required. Subsequent confirmation of a diagnosis of cutaneous leishmaniasis is best achieved by demonstration of the organism on skin biopsy, aspiration or smear. The histology is variable and depends on geographic, parasite species and host factors. Speciation of New World disease as either Leishmania braziliensis or Leishmania mexicana is important to determine the risk of later development of mucosal disease, which normally only occurs with L. braziliensis infection, and for optimal treatment. Several different modes of treatment have been suggested, but antimonials, such as sodium stibogluconate, remain the treatment of choice in New World cutaneous leishmaniasis.