Double Infection With Leishmania tropica and L. major in an HIV Patient Controlled With High Doses of Amphotericin B

Recurrent mucosal leishmaniasis of the epiglottis in an immunosuppressed patient

Leishmaniasis is a disease caused by the intracellular protozoan parasite Leishmania and are known more than 20 species(1) harmful for men. A 74-year-old man, with sarcoidosis treated with methotrexate and corticoid, was assessed, in 2021, by an ENT specialist due to dysphagia, dysphonia, and odynophagia with a 5-year evolution and progressive worsening. A biopsy of the right vocal cord and epiglottis was performed, and the histology demonstrated the presence of amastigotes in the tissues coloured by Giemsa making the diagnosis of Leishmaniasis. The patient was referred to the Infectious Diseases Department, with the diagnosis of mucosal leishmaniasis, and hospitalized for treatment with Liposomal Amphotericin B. The dysphagia and odynophagia improved and was discharged to Infectious Diseases Day hospital to continue treatment. He completed a total of 10 days of treatment and continued follow up in Infectious Diseases, Pneumology and ENT departments. During this time the patient stopped treatment with methotrexate but maintained deflazacort 6 mg per day. In 2023, the patient presented with worsening dysphonia and dysphagia. A new biopsy of the epiglottis was performed in the ENT department. Leishmania DNA was detected, and histology was compatible with Leishmaniasis of the left larynx. He was hospitalized in Infectious Diseases department and started treatment with Liposomal Amphotericin B. The patient completed a total of 10 days of treatment, and, by this time, the medical team decided to maintain suppressive therapy once a month with Liposomal Amphotericin B, until the patient present with a CD4 leucocyte count superior to 350/mm³ . By the time of this article, the patient maintained follow up in the Infectious Disease department with monthly sessions of therapy.

A difficult to treat Leishmania infantum relapse after allogeneic stem cell transplantation

Here we describe a complicated case of a relapsed Leishmania infantum infection after an allogeneic stem cell transplantation (allo-SCT) for primary myelofibrosis. Three years earlier the patient had been diagnosed with a hemophagocytic lymphohistiocytosis secondary to a visceral Leishmania infantum infection, for which he was effectively treated with a cumulative dose of 40 mg/kg liposomal amphotericin B. During the first disease episode he was also diagnosed with primary myelofibrosis for which he received medical follow-up. One year later ruxolitinib was started due to progressive disease. No Leishmania relapse occurred. Nevertheless, the marrow fibrosis progressed, and an allo-SCT was performed. Two months after allo-SCT prolonged fever and a persistent pancytopenia occurred, which was due to a relapse of visceral Leishmaniasis. The infection was refractory to a prolonged treatment with liposomal amphotericin B with a cumulative dose up to 100 mg/kg. Salvage treatment with miltefosine led to reduction of fever within a few days and was followed by a slow recovery of pancytopenia over the following months. The Leishmania parasite load by PCR started to decline and after 3.5 months no Leishmania DNA could be detected anymore and follow-up until ten months afterwards did not show a relapse.

Non-Endemic Leishmaniases Reported Globally in Humans between 2000 and 2021—A Comprehensive Review

Leishmaniases are human and animal parasitic diseases transmitted by phlebotomine sand flies. Globalization is an important driver of the burden and in the current dynamics of these diseases. A systematic review of articles published between 2000 and 2021 was conducted using the PubMed search engine to identify the epidemiology and clinical management of imported human leishmaniases as a fundamental step to better manage individual cases and traveler and migrant health from a global perspective. A total of 275 articles were selected, representing 10,341 human imported cases. Identified drivers of changing patterns in epidemiology include conflict and war, as well as host factors, such as immunosuppression, natural and iatrogenic. Leishmania species diversity associated with different clinical presentations implies diagnostic and treatment strategies often complex to select and apply, especially in non-endemic settings. Thus, diagnostic and management algorithms for medical clinical decision support are proposed. Increased surveillance of non-endemic cases, whether in vulnerable populations such as refugees/migrants and immunocompromised individuals or travelers, could improve individual health and mitigate the public health risk of introducing Leishmania species into new areas.

Amplicon-based next-generation sequencing reveals the co-existence of multiple Leishmania species in patients with visceral leishmaniasis

Visceral leishmaniasis (VL) is a mammalian protozoal disease propagated in the Americas by female phlebotomine sandflies, mainly caused by Leishmania infantum. However, in recent years, cases of VL caused by different Leishmania species, such as L. amazonensis and L. colombiensis, have been reported in the continent. This study used an amplicon-based next-generation sequencing approach to identify VL aetiologic species using high-depth sequencing targeting a region on the Heat Shock Protein 70 gene. In this first approach, six samples from five patients diagnosed with VL were selected and analysed to identify DNA of Leishmania spp. All samples harboured DNA of L. infantum; five samples were found to be co-infected with other Leishmania spp. or with Trypanosoma cruzi, and just one sample was mono-infected with L. infantum. This study demonstrates the usefulness of this methodology to identify trypanosomatid co-infections in clinical samples, which presents an interesting study panorama considering their biological, clinical and epidemiological implications.

Endlicheria bracteolata (Meisn.) Essential Oil as a Weapon Against Leishmania amazonensis: In Vitro Assay

The difficulties encountered and the numerous side effects present in the treatment of cutaneous leishmaniasis have encouraged the research for new compounds that can complement or replace existing treatment. The growing scientific interest in the study of plants, which are already used in folk remedies, has led our group to test Endlicheria bracteolata essential oil against Leishmania amazonensis. Several species of the Lauraceae family, or their compounds, have relevant antiprotozoal activities Therefore, the biological potential on L. amazonensis forms from the essential oil of Endlicheria bracteolata leaves was verified for the first time in that work. The antileishmanial activity was evaluated against promastigotes and intracellular amastigotes, and cytotoxicity were performed with J774.G8, which were incubated with different concentrations of E. bracteolata essential oil. Transmission electron microscopy and flow cytometry were performed with E. bracteolata essential oil IC₅₀. Promastigote forms showed E. bracteolata essential oil IC₅₀ of 7.945 ± 1.285 µg/mL (24 h) and 6.186 ± 1.226 µg/mL (48 h), while for intracellular amastigote forms it was 3.546 ± 1.184 µg/mL (24 h). The CC₅₀ was 15.14 ± 0.090 µg/mL showing that E. bracteolata essential oil is less toxic to macrophages than to parasites. Transmission electron microscopy showed that E. bracteolata essential oil treatment is capable of inducing mitochondrial damage to promastigote and intracellular amastigote forms, while flow cytometry showed ΔѰm disruption in treated parasites. These results could bring about new possibilities to develop products based on E. bracteolata essential oil to treat cutaneous leishmaniasis, especially for people who cannot receive the conventional therapy.