Distinguishing post-kala-azar dermal leishmaniasis from leprosy: experience in the Sudan

Para Kala-Azar Dermal Leishmaniasis: A Case Report

Rarely, post-kala-azar dermal leishmaniasis (PKDL) may coexist with visceral leishmaniasis (VL). The concomitant PKDL and VL are referred to as Para-kala-azar dermal Leishmaniasis. We report a case of Para kala-azar dermal leishmaniasis in a chronic Hepatitis-B virus-infected patient who presented with an abdominal lump and multiple maculopapular skin lesions and is resistant to sodium stibogluconate but successfully treated with liposomal Amphotericin-B.

Post-kala-azar dermal leishmaniasis and leprosy: case report and literature review

Background

Post-kala-azar dermal leishmaniasis (PKDL) is a dermal complication of visceral leishmaniasis (VL), which may occur after or during treatment. It has been frequently reported from India and the Sudan, but its occurrence in South America has been rarely reported. It may mimic leprosy and its differentiation may be difficult, since both diseases may show hypo-pigmented macular lesions as clinical presentation and neural involvement in histopathological investigations. The co-infection of leprosy and VL has been reported in countries where both diseases are endemic. The authors report a co-infection case of leprosy and VL, which evolved into PKDL and discuss the clinical and the pathological aspects in the patient and review the literature on this disease.

Case presentation

We report an unusual case of a 53-year-old female patient from Alagoas, Brazil. She presented with leprosy and a necrotizing erythema nodosum, a type II leprosy reaction, about 3 month after finishing the treatment (MDT-MB) for leprosy. She was hospitalized and VL was diagnosed at that time and she was successfully treated with liposomal amphotericin B. After 6 months, she developed a few hypo-pigmented papules on her forehead. A granulomatous inflammatory infiltrate throughout the dermis was observed at histopathological examination of the skin biopsy. It consisted of epithelioid histiocytes, lymphocytes and plasma cells with the presence of amastigotes of Leishmania in macrophages (Leishman’s bodies). The diagnosis of post-kala-azar dermal leishmaniasis was established because at this time there was no hepatosplenomegaly and the bone marrow did not show Leishmania parasites thus excluding VL. About 2 years after the treatment of PKDL with liposomal amphotericin B the patient is still without PKDL lesions.

Conclusion

Post-kala-azar dermal leishmaniasis is a rare dermal complication of VL that mimics leprosy and should be considered particularly in countries where both diseases are endemic. A co-infection must be seriously considered, especially in patients who are non-responsive to treatment or develop persistent leprosy reactions as those encountered in the patient reported here.

Clinicopathological and Immunological Changes in Indian Post Kala-Azar Dermal Leishmaniasis (PKDL) Cases in relation to Treatment: A Retrospective Study

Post-kala-azar dermal leishmaniasis (PKDL) is an important factor in kala-azar transmission; hence its early detection and assessment of effective treatment is very important for disease control. In present study on 60 PKDL cases presented with macular, mixed papulonodular, or erythematous lesions, Leishmania parasites were demonstrated microscopically in 91% of papulonodular and 40% of macular lesions. Cellular infiltrates in skin biopsy imprint smears from lesions were mononuclear cells, 25–300/OIF (oil immersion field), predominantly histiocytes with vacuolation, many lymphocytes, some plasma cells, and Leishmania amastigotes 0–20/OIF. Cases with no demonstrable parasites were diagnosed on the basis of past history of VL, lesion's distribution, cytopathological changes, and positive DAT (86.83%). Following antileishmanial treatment with SAG, papulonodular forms of PKDL lesions disappeared clinically but microscopically the mononuclear cells (20–200/OIF) persisted in the dermal lesions. Response observed in macular PKDL lesions was poor which persisted both clinically and cytopathologically. Follow-up of PKDL will assess the effectivity of treatment as either disappearance of lesions or any relapse. Studies on involvement of immunological factors, that is, certain cytokines (IL-10, TGF-β, etc.) and chemokines (macrophage inflammatory protein, MIP 1-α, etc.) in PKDL, may provide insight for any role in the treatment response.

Efficacy of liposomal amphotericin B (AmBisome®) in the treatment of persistent post-kala-azar dermal leishmaniasis (PKDL)

A dermatosis commonly known as post-kala-azar dermal leishmaniasis (PKDL) may develop following the treatment of human visceral leishmaniasis (VL). In about 15% of PKDL cases the disfiguring lesions persist, sometimes for many years. Such persistent lesions currently require daily injections of sodium stibogluconate (SSG) for 2-4 months and even then treatment may not be successful. Alternative, quicker and cheaper treatment options that cause less toxicity are being explored. Immuno-chemotherapeutic regimens (based on leishmaniasis candidate vaccines/BCG with SSG) are still experimental but treatment with liposomal amphotericin B (AmBisome) has already been found effective, albeit in a small number of patients. AmBisome is considered less nephrotoxic than non-liposomal amphotericin B because it specifically targets the macrophages in which the Leishmania parasites develop. The aim of the present study was to evaluate further the usefulness of AmBisome in the treatment of persistent PKDL, in Sudan. The 12 subjects, all of whom gave their informed consent, had each had PKDL lesions for >6 months and shown no improvement after repeated injections of SSG. During the study period, they were hospitalized and regularly screened, haematologically and biochemically, for adverse effects. The AmBisome, given intravenously at 2.5 mg/kg.day for 20 days, completely cleared the skin rash of 10 (83%) of the patients and caused no detectable adverse effects. In the 10 patients who responded well to the treatment, the papular lesions regressed and became flat while the hypopigmented lesions darkened (continuing to do so even after the last AmBisome injections). Treatment outcome appeared to be unaffected by the age or gender of the patient (P = 0.7 for each) but the time taken for the PKDL lesions to heal was correlated with the age of the lesions (P = 0.009). The macular lesions healed more slowly than the papular (P = 0.02). In conclusion, Ambisome appears suitable for the treatment of persistent PKDL lesions in Sudan. Once certain favourable clinical signs (the regression and/or darkening of the PKDL lesions) have been noted, the lesions will probably continue to clear without the need for more injections.

Systematic Review into Diagnostics for Post-Kala-Azar Dermal Leishmaniasis (PKDL)

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.

Leishmania promastigote membrane antigen-based enzyme-linked immunosorbent assay and immunoblotting for differential diagnosis of Indian post-kala-azar dermal leishmaniasis

Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), caused by Leishmania donovani, is difficult, as the dermal lesions are of several types and resemble those caused by other skin diseases, especially leprosy. Since the disease generally appears very late after the clinical cure of kala-azar in India, it is also difficult to correlate PKDL with a previous exposure to L. donovani. Very few attempts have been made so far to diagnose PKDL serologically, and the diagnostic methods vary in their sensitivities and specificities. Diagnosis of PKDL through sophisticated PCR methods, although highly sensitive, has limited practical use. We have developed a serodiagnostic method using an enzyme-linked immunosorbent assay to detect specific immunoglobulin (Ig) isotypes and IgG subclass antibodies in the sera of Indian PKDL patients. Our assay, which uses L. donovani promastigote membrane antigens, was 100% sensitive for the detection of IgG and 96.7% specific for the detection of IgG and IgG1. Optical density values for individual patients, however, demonstrated wide variations. Western blot analysis based on IgG reactivity could differentiate patients with PKDL from control subjects, which included patients with leprosy, patients from areas where kala-azar is endemic, and healthy subjects, by the detection of polypeptides of 67, 72, and 120 kDa. The recognition patterns of the majority of serum samples from patients with PKDL were also distinct from those of the serum samples from patients with visceral leishmaniasis (VL), at least for a 31-kDa polypeptide. To further differentiate patients with PKDL from those with active and cured VL, we analyzed the specific titers of the Ig isotypes and IgG subclasses. High levels of IgG, IgG1, IgG2, and IgG3 antibodies significantly differentiated patients with PKDL from patients cured of VL. The absence of antileishmanial IgE and IgG4 in patients with PKDL differentiated these patients from those with active VL. These results imply intrinsic differences in the antibodies generated in the sera from patients with PKDL and VL.

4. Post kala-azar dermal leishmaniasis

Post kala-azar dermal leishmaniasis (PKDL) is increasingly recognized in Sudan as a complication of visceral leishmaniasis (VL), occurring in c. 55% of patients after, or during treatment of, VL. The development of PKDL seems to be restricted to parasites of the Leishmania donovani sensu stricto cluster; no particular zymodeme has been found to be associated with it. In contrast to PKDL in India, PKDL in Sudan occurs within 0-6 months after treatment for VL. The rash may be macular, maculo-papular or nodular, and spreads from the perioral area to other parts of the body, depending on grade of severity. Young children are particularly at risk of developing more severe disease. In 16% of PKDL patients, parasites can be demonstrated by microscopy in lymph node or bone marrow aspirates and, with the aid of the polymerase chain reaction (PCR), in lymph nodes of 81% of patients, possibly indicating persistent visceralized infection. Diagnosis can be made by demonstration of parasites in skin smears or biopsies in 20-30% of cases; newer techniques, using PCR with skin smears, have higher sensitivity (83%). Monoclonal antibodies against L. donovani can detect parasites in 88% of biopsies. Serological tests are of limited value. The leishmanin skin test is positive in 50-60% of cases; there is an inverse relationship between the skin test result and severity of PKDL. In differential diagnosis, miliaria rubra is the most common problem; differentiation from leprosy is the most difficult. In biopsies, hyperkeratosis, parakeratosis, acanthosis, follicular plugging and liquefaction degeneration of the basal layer may be found in the epidermis; in the dermis there are varying intensities of inflammation with scanty parasites and mainly lymphocytes; macrophages and epithelioid cells may also be found. In 20% of cases discrete granulomas may be found. After VL, the immune response shifts from a Th2-type to a mixed Th1/Th2-type. High levels of interleukin-10 in skin biopsies as well as in peripheral blood mononuclear cells and plasma in patients with VL predict the development of PKDL. Treatment is needed only for those who have severe and prolonged disease; sodium stibogluconate (20 mg/kg/d for 2 months) is usually sufficient. (Liposomal) amphotericin B is effective, whereas ketoconazole, terbinafine and itraconazole are not.

Detection and characterization of Leishmania in tissues of patients with post kala-azar dermal leishmaniasis using a specific monoclonal antibody

Sections from skin lesions and draining lymph nodes of patients with post kala-azar dermal leishmaniasis were examined using an immunoperoxidase method and a monoclonal antibody directed against Leishmania donovani. Parasites were detected in 22 of 25 biopsies (88%). In parallel sections stained by haematoxylin and eosin, parasites were detected in only 5 of 25 of the biopsies (20%). The demonstration of whole parasites or parasite antigen is diagnostic.