Visceral leishmaniasis among liver transplant recipients: an overview

Visceral Leishmaniasis in a Liver Transplant Patient: A Case Report

Leishmaniasis is an infection caused by protozoa of the genus Leishmania, transmitted by sandflies and endemic to more than 88 countries. Visceral leishmaniasis in immunosuppressed patients is a growing concern. We report the case of a 61-year-old male patient with a previous history of alcoholic cirrhosis and portal vein thrombosis who underwent liver transplantation for the treatment of hepatocellular carcinoma. Thirty-six days after the procedure, the patient showed an increase in liver enzymes and was diagnosed with moderate acute rejection of the graft. He was treated with high-dose intravenous corticosteroids, and while showing improvement in biochemical markers, he became febrile 12 days after corticosteroid treatment. He presented daily episodes of fever, even after the use of several antimicrobial, antiviral, and antifungal agents, and a number of negative cultures from different sites were obtained. A bone marrow biopsy was then performed, showing a large number of amastigote forms of Leishmania spp. Treatment with liposomal amphotericin B was initiated; however, the patient progressed to refractory septic shock and death. This case highlights several aspects of visceral leishmaniasis in liver transplant recipients, such as the association of malnutrition to Leishmania infection and the challenges of diagnosing leishmaniasis in cirrhotic patients in which splenomegaly and pancytopenia, the hallmarks of leishmaniasis, may also be attributed to portal hypertension and end-stage liver disease. A high index of suspicion is necessary for the correct diagnosis and treatment of leishmaniasis in this group of patients. This study is compliant with the Helsinki Congress and the Istanbul Declaration.

Solid Organ Transplant and Parasitic Diseases: A Review of the Clinical Cases in the Last Two Decades

The aim of this study was to evaluate the occurrence of parasitic infections in solid organ transplant (SOT) recipients. We conducted a systematic review of literature records on post-transplant parasitic infections, published from 1996 to 2016 and available on PubMed database, focusing only on parasitic infections acquired after SOT. The methods and findings of the present review have been presented based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist. From data published in the literature, the real burden of parasitic infections among SOT recipients cannot really be estimated. Nevertheless, publications on the matter are on the increase, probably due to more than one reason: (i) the increasing number of patients transplanted and then treated with immunosuppressive agents; (ii) the “population shift” resulting from immigration and travels to endemic areas, and (iii) the increased attention directed to diagnosis/notification/publication of cases. Considering parasitic infections as emerging and potentially serious in their evolution, additional strategies for the prevention, careful screening and follow-up, with a high level of awareness, identification, and pre-emptive therapy are needed in transplant recipients.

Validation of rK39 immunochromatographic test and direct agglutination test for the diagnosis of Mediterranean visceral leishmaniasis in Spain

Background

Visceral leishmaniasis (VL), the most severe form of leishmaniasis, is endemic in Europe with Mediterranean countries reporting endemic status alongside a worrying northward spread. Serological diagnosis, including immunochromatographic test based on the recombinant antigen rK39 (rK39-ICT) and a direct agglutination test (DAT) based on the whole parasite antigen, have been validated in regions with high VL burden, such as eastern Africa and the Indian subcontinent. To date, no studies using a large set of patients have performed an assessment of both methods within Europe.

Methodology/Principal findings

We selected a range of clinical serum samples from patients with confirmed VL (including HIV co-infection), Chagas disease, malaria, other parasitic infections and negative samples (n = 743; years 2009–2015) to test the performance of rK39-ICT rapid test (Kalazar Detect Rapid Test; InBios International, Inc., USA) and DAT (ITM-DAT/VLG; Institute of Tropical Medicine Antwerp, Belgium). An in-house immunofluorescence antibody test (IFAT), was included for comparison. Estimated sensitivities for rK39-ICT and DAT in HIV-negative VL patients were 83.1% [75.1–91.2] and 84.2% [76.3–92.1], respectively. Sensitivity was reduced to 67.3% [52.7–82.0] for rK39 and increased to 91.3% [82.1–100.0] for DAT in HIV/VL co-infected patients. The in-house IFAT was more sensitive in HIV-negative VL patients, 84.2% [76.3–92.1] than in HIV/VL patients, 79.4% [73.3–96.2]. DAT gave 32 false positives in sera from HIV-negative VL suspects, compared to 0 and 2 for rK39 and IFAT, respectively, but correctly detected more HIV/VL patients (42/46) than rK39 (31/46) and IFAT (39/46).

Conclusions/Significance

Though rK39-ICT and DAT exhibited acceptable sensitivity and specificity a combination with other tests is required for highly sensitive diagnosis of VL cases in Spain. Important variation in the performance of the tests were seen in patients co-infected with HIV or with other parasitic infections. This study can help inform the choice of serological test to be used when screening or diagnosing VL in a European Mediterranean setting.

Visceral leishmaniasis is the most severe form of leishmaniasis, a disease transmitted through the bite of an infected sandfly. Although the biggest burden of leishmaniasis is in eastern Africa and the Indian subcontinent, the disease is also endemic in parts of Europe. Previous studies have looked at performance of diagnostic methods, but not in great detail on samples derived from a European setting. Using a large set of samples from a national reference laboratory in Madrid, Spain, we assessed a leishmaniasis rapid test and a direct agglutination test for serological diagnosis of visceral leishmaniasis in Europe. Both tests were effective at diagnosing VL, but important differences were seen when testing patients co-infected with HIV or with other parasitic infections. This study can help inform which diagnostic tests are suitable for use in a European Mediterranean setting.

Leishmaniasis in solid organ and hematopoietic stem cell transplant recipients

Leishmaniasis occurs in <1% of solid organ and hematopoietic stem cell transplant recipients in endemic countries in which transplants are performed. Visceral leishmaniasis (VL) makes up the bulk of reported cases. The onset generally occurs months after transplantation and the mode of acquisition is often impossible to determine, but de novo vector-borne infection and reactivation of inapparent infection are thought to be the principal means. The potential role of clinically inapparent donor infection is uncertain and screening is not currently recommended, nor is it recommended for recipients from endemic areas, some of whom may have detectable circulating protozoan nucleic acid. While transplant recipients with VL often present with the non-specific findings of fever and cytopenia, the additional presence of hepatosplenomegaly in patients from endemic areas should lead to a directed diagnostic evaluation with bone marrow examination and PCR testing of marrow and peripheral blood having a high yield. Management may often be complicated by the presence of concomitant infections. A lipid formulation of amphotericin B is the preferred treatment, especially for VL, but the relapse rate in transplant recipients is approximately 25%. PCR monitoring of blood for either secondary prophylaxis or preemptive therapy requires further study.

Visceral leishmaniasis after orthotopic liver transplantation: a rare cause of infection

Visceral leishmaniasis (VL) was known as an opportunistic infection associated with immunosuppression, particularly related to human immunodeficiency virus infection and rarely to solid organ transplant recipients. We report a case of VL, 6 months after liver transplantation, in a patient who presented with febrile pancytopenia. The diagnosis was made by demonstration of amastigotes in smears from bone marrow. VL is a very rare infection in patients who undergo liver transplantation and, to our knowledge, this is the first case diagnosed in Portugal.

Risk factors, clinical features and outcomes of visceral leishmaniasis in solid-organ transplant recipients: a retrospective multicenter case-control study

Visceral leishmaniasis (VL) is a rare disease in solid-organ transplant (SOT) recipients. Therefore, little is known about the risk factors and disease behavior in the transplant setting. This multicenter, matched case-control study (1:2 ratio) was designed to determine the risk factors, clinical features and outcomes of VL among this population. Control and case subjects were matched by center, transplant type and timing. Thirty-six VL cases were identified among 25 139 SOT recipients (0.1%). VL occurred 5.7-fold more frequently in Brazil than in Spain, presenting a median time of 11 months after transplantation. High-dose prednisone in the preceding 6 months was associated with VL. Patients were diagnosed over 1 month after symptom onset in 25% of cases. Thirty-one patients (86%) were febrile upon diagnosis, 81% exhibited visceromegaly and 47% showed pancytopenia. Concomitant infection was common. Parasites were identified in 89% of patients; the remaining patients were diagnosed by serology. The majority of the patients received amphotericin B. Relapses occurred in 25.7% of cases, and the crude mortality rate was 2.8%. VL after SOT is related to the VL prevalence in the general population. Delayed diagnosis frequently occurs. Liposomal amphotericin is the most commonly used therapy; mortality is low, although relapses are common.

Atypical presentation of cutaneous leishmaniasis in a renal transplant recipient successfully treated with allopurinol and fluconazole

Leishmaniasis is a zoonotic infection acquired through the bite of a female sandfly, which introduces the amastigotes of Leishmania into the bloodstream. Cutaneous leishmaniasis is rare after solid organ transplantation. Its diagnosis is difficult in immunosuppressed patients. We report a case of isolated cutaneous leishmaniasis in a renal transplant patient resident in an endemic area. The patient was successfully treated with allopurinol and fluconazole and has remained relapse-free for 44 months. The diagnosis of cutaneous leishmaniasis must be considered in immunosuppressed patients living in endemic areas. Our report shows that cutaneous leishmaniasis may complicate the clinical course of kidney transplant recipients and its presentation can be atypical. Conventional treatment with pen.tavalent antimonial agents can cause many side effects; of particular concern in renal transplant pa.tients are pancreatitis and nephrotoxicity. These latter may be avoided by using a combination of allopurinol and fluconazole.

New challenges in the epidemiology and treatment of visceral leishmaniasis in periurban areas

Visceral leishmaniasis [VL] represents a major public health problem in many areas of the world. This review focuses on the impact of periurbanization on the epidemiology and treatment of VL, using Brazil as an example. VL continues to be mostly a disease of poverty with impact on families. However, the disease has expanded in Latin America, with foci reported as far south as Argentina. There is an increasing overlap of Leishmania infantum chagasi and HIV infections and other immunosuppressive conditions, resulting in VL emerging as an opportunistic infection. This new setting poses new challenges for VL disease control and patient management.

Asymptomatic Leishmania infantum infection in an area of northwestern Italy (Piedmont region) where such infections are traditionally nonendemic

The prevalence of Leishmania infantum-specific antibodies and asymptomatic infection was assessed in a randomized sample of 526 healthy adults from a continental area of northwestern Italy where L. infantum is not endemic and where autochthonous cases of visceral leishmaniasis (VL) were recently reported. L. infantum-specific antibodies were detected by Western blotting (WB) in 39 subjects (7.41%), while L. infantum kinetoplast DNA was amplified from buffy coat in 21 out of 39 WB-positive subjects, confirming asymptomatic infection in 53.8% of seropositives. Risk factors significantly associated with WB positivity were uninterrupted residence since childhood in a local rural environment (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.7 to 7.3), daily contact with animals though not exclusively with dogs (OR, 3.7; 95% CI, 1.3 to 10.7), older age (OR, 2.31; 95% CI, 1.2 to 4.5), and agricultural/other outdoor activities (OR, 3.8; 95% CI, 0.99 to 3.7.) Logistic regression analysis showed that uninterrupted residence in a local rural environment and an age of >65 years were the only independent predictors of seropositivity assessed by WB. Follow-up at 24 months did not show evidence of VL in either seropositive or PCR-positive subjects. The detection of a high seroprevalence rate, confirmed as asymptomatic infection by PCR in more than half of the cases, among healthy residents in a continental area of northwestern Italy makes local L. infantum transmission very likely. In a region where VL is considered nonendemic, these findings warrant further epidemiological investigations as well as interventions with respect to both the canine reservoir and vectors, given the possible risks for immunosuppressed patients.