Epidemiology, clinical pattern and impact of species-specific molecular diagnosis on management of leishmaniasis in Belgium, 2010-2018: A retrospective study

American Cutaneous Leishmaniasis: Imported cases in Berlin 2000-2023

BACKGROUND

American Cutaneous Leishmaniasis (ACL) shows variable response to therapy, but data on species-specific treatment efficacy is scarce. We describe the clinical characteristics and outcome of patients with ACL imported to a tertiary centre in Germany and determine whether species-specific therapy according to the 2014 "LeishMan" group recommendations is associated with cure.

METHODS

A retrospective chart review was conducted at the Charité Institute of International Health in Berlin. We analysed data on PCR-confirmed ACL cases collected between 2000 and 2023. Systemic therapy included liposomal amphotericin B, miltefosine, pentavalent antimony, ketoconazole or itraconazole. Localized therapy included perilesional pentavalent antimony or paromomycin ointment. Cure was defined as re-epithelialization of ulcers or disappearance of papular-nodular lesions after 3 months of treatment. Logistic regression models were used to quantify the effect of species-specific systemic therapy on the outcome.

RESULTS

75 cases were analysed. Most patients were male (62%), median age was 35 years, no patient had a history of immunosuppression. The most common reason for travel was tourism (60%), the most common destination was Costa Rica (28%), the median duration of illness was 8 weeks, and most patients presented with ulcers (87%). Lesions were complex in 43%. The most common Leishmania (L.) species was L. braziliensis (28%), followed by L. panamensis (21%). 51/73 (70%) patients were cured after initial therapy and 17/21 (81%) after secondary therapy. Cure after systemic therapy was more frequent when species-specific treatment recommendations were followed (33/45; 73%), compared to when not followed, (6/17; 35%, P = 0.008). This association was independent of age, sex, previous therapy, complex lesions, and Leishmania species (adjusted OR, 5.06; 95% CI, 1.22-24.16).

CONCLUSIONS

ACL is a rare, imported disease in Germany. Complex lesions were common, challenging successful therapy. This study highlights the importance of identifying the parasite species and suggests that a species-specific approach to treatment leads to better outcomes.

Delayed diagnosis among patients with visceral leishmaniasis

We aimed to estimate the diagnostic latency of patients with visceral leishmaniasis (VL). A monocentric retrospective observational study was conducted including all confirmed cases of VL diagnosed from January 2005 to March 2022. Epidemiological and clinical characteristics of patients with VL were collected. The diagnostic latency was defined as the number of days between the first contact with a health-care provider for signs and/or symptoms referable to VL and the laboratory diagnosis of leishmaniasis. Twenty-four cases of VL were included in the study, mostly male (75%) and Italians (79.2%), with a median age of 40 years [Inter Quartile Range (IQR 30-48)]. Fourteen (58.3%) VL cases were people living with HIV (PLWH) and 4 (16.6%) subjects were on immunosuppressive therapy. For VL the median diagnostic latency was 54 days (IQR 28-162). The shorter diagnostic latency was observed in PLWH [31 days (IQR 20-47)] followed by immunocompetent patients [160 days (IQR 133-247)] and those on immunosuppressive therapy [329 days (IQR 200-678)]. Twelve patients (50%) reported at least one medical encounter before the diagnosis of VL and 6 patients received a wrong therapy. Diagnostic delay in VL was significant in patients under immune suppressive treatment.

Imported cases of cutaneous leishmaniasis in Cuba, 2017: role of human movement

Background

Leishmaniasis is a vector-borne disease caused by several species from genus Leishmania. An increase in the number of cases related to human movement has been informed in the last years. Due to the increase of suspicious leishmaniasis cases arriving in Cuba during 2017, a general analysis is presented herein.

Methods

Clinical samples were collected from 5 patients suspicious of leishmaniasis, received from January to December 2017 at the Institute of Tropical Medicine Pedro Kourí, Cuba. Skin lesion samples were analyzed using different diagnostic assays: direct smear, histological examination, and molecular analysis for species identification. Epidemiological and demographic data were requested from each case and analyzed. Treatment and follow up of patient was also performed.

Results

Five cases were confirmed as Leishmania infection according to microscopic observation and molecular methods results. PCR-18S, PCR-N/RFLP and PCR-F/RFLP identified the following species: L. panamensis (2 cases), L. braziliensis (1 case), L.panamensis/L.guyanensis (1 case), L. mexicana complex (1 case). In treated patients, drugs were well tolerated, cure were documented and no relapse have been currently reported (3 years later).

Conclusions

Clinical characteristics, demographic data, and epidemiological features of infection for each case evidence the potential risk related with travel to endemic areas of leishmaniasis.

Keyworks

Cutaneous leishmaniasis, Epidemiology, Imported cases.

Establish an allele-specific real-time PCR for Leishmania species identification

Background

Leishmaniasis is a serious neglected tropical disease that may lead to life-threatening outcome, which species are closely related to clinical diagnosis and patient management. The current Leishmania species determination method is not appropriate for clinical application. New Leishmania species identification tool is needed using clinical samples directly without isolation and cultivation of parasites.

Methods

A probe-based allele-specific real-time PCR assay was established for Leishmania species identification between Leishmania donovani and L. infantum for visceral leishmaniasis (VL) and among L. major, L. tropica and L. donovani/L. infantum for cutaneous leishmaniasis (CL), targeting hypoxanthine-guanine phosphoribosyl transferase (HGPRT) and spermidine synthase (SPDSYN) gene with their species-specific single nucleotide polymorphisms (SNPs). The limit of detection of this assay was evaluated based on 8 repeated tests with intra-assay standard deviation < 0.5 and inter-assay coefficients of variability < 5%. The specificity of this assay was tested with DNA samples obtained from Plasmodium falciparum, Toxoplasma gondii, Brucella melitensis and Orientia tsutsugamushi. Total 42 clinical specimens were used to evaluate the ability of this assay for Leishmania species identification. The phylogenetic tree was constructed using HGPRT and SPDSYN gene fragments to validate the performance of this assay.

Results

This new method was able to detect 3 and 12 parasites/reaction for VL and CL respectively, and exhibited no cross-reaction with P. falciparum, T. gondii, B. melitensis, O. tsutsugamushi and non-target species of Leishmania. Twenty-two samples from VL patients were identified as L. donovani (n = 3) and L. infantum (n = 19), and 20 specimens from CL patients were identified as L. major (n = 20), providing an agreement of 100% compared with sequencing results. For further validation, 29 sequences of HGPRT fragment from nine Leishmania species and 22 sequences from VL patients were used for phylogenetic analysis, which agreed with the results of this new method. Similar results were obtained with 43 sequences of SPDSYN fragment from 18 Leishmania species and 20 sequences from CL patients.

Conclusions

Our assay provides a rapid and accurate tool for Leishmania species identification which is applicable for species-adapted therapeutic schedule and patient management.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-022-00992-y.

Cutaneous leishmaniasis in travellers and migrants: a 10-year case series in a Canadian reference centre for tropical diseases

BACKGROUND

Cutaneous leishmaniasis is increasingly encountered in returned travellers and migrants to nonendemic countries. We sought to describe the clinical characteristics and treatment outcomes of cases of cutaneous leishmaniasis diagnosed at our reference centre over a 10-year period.

METHODS

This case series included all laboratory-confirmed cases of cutaneous leishmaniasis in travellers and migrants for whom complete clinical data were available, diagnosed between January 2008 and October 2018 at the J.D. MacLean Centre for Tropical Diseases in Montréal. We examined the number of cases each year. We used descriptive statistics to summarize variables (e.g., demographic characteristics, travel history, clinical presentation, diagnostic methods, treatments, adverse events) extracted from the patients' electronic medical records. The primary outcome for evaluating clinical response to treatment was defined as the complete re-epithelialization of the wound surface at 1 year.

RESULTS

We identified 48 patients who received diagnoses of cutaneous leishmaniasis in the 10-year study period, including 33 exposed in the Americas and 15 exposed in other regions (median age 43.5 [range 1-75] yr); 28 [58%] males). The annual number of cases increased from 9 in 2008/09 to 16 in 2017/18. The median time from onset to diagnosis was 89 (IQR 58-134) days. Liposomal amphotericin B was the most commonly used initial treatment (20 [53%] patients). Thirty-five patients completed their follow-up, and 11 had successful response to 1 course of liposomal amphotericin B. Adverse events (including acute kidney injury, increased pancreatic enzymes and fatigue) were reported in 6 (30%) patients. Clinical cure was achieved within 1 year for 32 (91%) of the 35 patients who completed follow-up.

INTERPRETATION

This study showed an increase in the number of cases of cutaneous leishmaniasis seen in our centre over the study period, likely because of increased travel and migration. This diagnosis should be considered in travellers and migrants with a chronic cutaneous lesion.

Autochthonous and imported tegumentary leishmaniasis in Catalonia (Spain): Aetiological evolution in the last four decades and usefulness of different typing approaches based on biochemical, molecular and proteomic markers

Leishmaniasis is a transmissible disease caused by Leishmania protozoa. Spain is endemic for both visceral and cutaneous leishmaniasis, the autochthonous aetiological agent being Leishmania infantum. Around the world, the L. donovani complex is associated with visceral symptoms, while any species of the Leishmania or Viannia subgenera affecting human can produce tegumentary forms. In a context of growing numbers of imported cases, associated with globalisation, the aim of this study was to analyse the aetiological evolution of human tegumentary leishmaniasis in a region of Spain (Catalonia). Fifty-six Leishmania strains, isolated from 1981 to 2018, were analysed using MLEE, gene sequencing (hsp70, rpoIILS, fh and ITS2) and MALDI-TOF. The utility of these different analytical methods was compared. The results showed an increase in leishmaniasis over the two last decades, particularly imported cases, which represented 39% of all cases studied. Leishmania infantum, L. major, L. tropica, L. braziliensis, L. guyanensis and L. panamensis were identified. The combination of molecular and enzymatic methods allowed the identification of 29 different strain types (A to AC). Strain diversity was higher in L. (Viannia), whilst the different L. major types were relatable with geo-temporal data. Among the autochthonous cases, type C prevailed throughout the studied period (39%). Minor types generally appeared within a short time interval. While all the techniques provided identical identification at the species complex level, MALDI-TOF and rpoIILS or fh sequencing would be the most suitable identification tools for clinical practice, and the tandem hsp70-ITS2 could substitute MLEE in the epidemiological field.