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Mucosal leishmaniasis (ML) is a parasitic disease affecting the mucosa of the upper respiratory tract and oral cavity. It is most prevalent in Central and South America, whereas cases in the Old World are relatively rare. Herein, we present the case of an immunocompetent man from Tunisia with a long-delayed diagnosis of ML, characterized by lesions in the nasal mucosa without cutaneous involvement. This report underlines the importance of multidisciplinary care and adherence to follow-up in managing this disease. Clinicians should remain vigilant regarding this parasitosis, its potential complications, and the need for accurate diagnosis and treatment.

Introduction: Cutaneous leishmaniases (CL), a wide range of cutaneous diseases caused by diverse species of Leishmania genus parasites, are among the most neglected infectious diseases. While they are non-fatal, CL are highly morbid with disfiguring lesions, which could be chronic, leaving lifelong unsightly scars; they are combined with psychological distress and social stigma. The efficiency of treatment highly depends on the infecting Leishmania species. Diagnosis is mainly based on microscopic direct examination (DE) of Giemsa-stained smears needing experienced microscopists. It can be laborious and time-consuming when the parasite load is low. DE is poorly sensitive and does not identify Leishmania species. So far, only DNA assays accurately identify the species. Despite their wide use for generic detection, PCR methods also require equipment and additional steps to identify causal Leishmania species. L. major is hyperendemic in many countries in Africa, the Middle East, and Asia, where other species co-occur with different endemicity levels according to the situations. This complicates disease management and treatment, particularly as distribution and epidemiology of leishmaniases remain poorly understood. Here, we aimed for a simple and rapid molecular diagnostic test to detect and identify L. major , a predominant CL causal species, which could be prone to become a control tool at the point of care, in endemic areas, using isothermal recombinase DNA amplification (recombinase polymerase amplification, RPA, or recombinase aided amplification, RAA) coupled to detection by the lateral flow (LF) chromatography on a PCRD cassette., Methods: To develop an L. major species-specific RPA-LF assay, computational analysis of 70 Leishmania DNA targets, identified through bibliography and database searches, selected five targets. We designed and tested 7 primer pairs/probe sets to specifically amplify L. major DNAs. First, the primers were tested for species specificity and sensitivity using basic RPA chemistry. Then, to develop RPA-coupled LF detection, we shifted to the nfo chemistry., Results: This way, we retained one set for further investigation, which confirmed it is L. major species-specific. Tested on 86 human cutaneous samples, this selected set was able to detect 100% of L. major infections in confirmed CL patients. We did not observe any cross-reactivity with lesions due to L. infantum or L. tropica ., Competing Interests: SR was employed by HDT Bio. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2025 Bel Hadj Ali, Saadi-Ben Aoun, Khammeri, Souguir, Harigua-Souiai, Chouaieb, Chakroun, Lemrani, Kallel, Kallel, Haddad, El Dbouni, Coler, Reed, Fathallah-Mili and Guizani.)

Background: Cutaneous Leishmaniases (CL), highly endemic in Africa and Mediterranean region, are caused by different Leishmania parasite species. Accurate species identification is crucial for effective diagnosis, treatment, and control of these diseases, but traditionally relies on DNA-based methods. High Resolution Melting analysis PCR (HRM PCR) provides rapid results and precise differentiation based on nucleotide variations. We hypothesized that the Strumpellin gene of Leishmania could serve as an effective target for developing a HRM PCR method for the rapid and efficient detection and identification of Leishmania species in CL diagnosis., Methodology: The Strumpellin gene was investigated in Trypanosomatidae family using bioinformatics and phylogenetic approaches to explore its evolutionary conservation and suitability for HRM PCR. HRM PCR target and primers were selected and validated on 73 different Leishmania DNAs. The analytical limit of detection was assessed, and the performance for detecting and identifying parasites in 38 cutaneous lesions aspirates was compared to Direct Examination (DE) and ITS1-PCR RFLP methods., Findings: The developed HRM PCR assay accurately identified promastigote DNAs of L. donovani/L. infantum, L. major, L. aethiopica, L. turanica, L. arabica, L. tarentolae and 3 genotypes of L. tropica. Differentiation was achievable with as little as a single nucleotide difference occurring within or between species. HRM profile interpretations were consistent with sequencing results of the HRM PCR target and identification by ITS1-PCR RFLP. The assay could detect the equivalent of 24 Leishmania parasites. In a small-scale sample, we brought proof of principle demonstration the HRM could detect and identify Leishmania in human cutaneous samples. In comparison to DE, the sensitivity and specificity of the HRM PCR assay on human cutaneous samples were 88% and 84.62%, respectively, while the ITS1-PCR assay evaluation parameters were 84% and 92.31%. Statistical analysis confirmed good correlation among the three tests, with both molecular methods providing congruent parasite identification. Notably, in three samples, only the HRM PCR assay was able to assign them to L. infantum or L. tropica., Conclusions: The HRM PCR assay is a valuable tool for the detection and identification of Old World Leishmania species. Its integration into molecular diagnostic algorithms for CL or in eco-epidemiological studies holds promise for improving disease management and control., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Saadi-Ben Aoun et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

With increasing concern about the negative health impact of fungal disease, there is a need to survey what is and is not known about the epidemiology of these infections in Tunisia. We have estimated the incidence and prevalence of the most serious fungal diseases in Tunisia for the first time. Using published literature from Tunisia, or if absent other countries, we have estimated the burden of life-threatening fungal infections and those causing significant morbidity, using deterministic modeling, based on populations at greatest risk. An estimated 250,494 (2.12% of the Tunisian population) are affected by a serious fungal disease annually. Invasive and chronic pulmonary aspergillosis are relatively common with 708 and 2090 patients affected, partly linked to the prevalence of chronic obstructive pulmonary disease (COPD). Fungal asthma (allergic bronchopulmonary aspergillosis and severe asthma with fungal sensitization) have an estimated prevalence of 38,264 (5.8% of the adult asthma population). Fungal keratitis probably affects 1,761 eyes annually, often leading to uniocular blindness. Candidaemia and Candida peritonitis probably affect at least 680 people annually, with a high mortality. Recurrent vulvovaginal candidiasis probably affects over 200,000 women. While fungal diseases are regularly diagnosed in Tunisia, epidemiological studies with denominators are uncommon. Some fungal diseases are poorly addressed with the current diagnostic portfolio, and surveillance is lacking. Studies on these diseases and the implementation of a national program of surveillance are required., Competing Interests: Declaration of competing interest None of the authors have a conflict of interest with the contents of this manuscript., (Copyright © 2024. Published by Elsevier Masson SAS.)

Background: Dipeptidyl peptidase III (DPPIII) member of M49 peptidase family is a zinc-dependent metallopeptidase that cleaves dipeptides sequentially from the N-terminus of its substrates. In Leishmania, DPPIII, was reported with other peptidases to play a significant role in parasites' growth and survival. In a previous study, we used a coding sequence annotated as DPPIII to develop and evaluate a PCR assay that is specific to dermotropic Old World (OW) Leishmania species. Thus, our objective was to further assess use of this gene for Leishmania species identification and for phylogeny, and thus for diagnostic and molecular epidemiology studies of Old World Leishmania species., Methodology: Orthologous DDPIII genes were searched in all Leishmania genomes and aligned to design PCR primers and identify relevant restriction enzymes. A PCR assays was developed and seventy-two Leishmania fragment sequences were analyzed using MEGA X genetics software to infer evolution and phylogenetic relationships of studied species and strains. A PCR-RFLP scheme was also designed and tested on 58 OW Leishmania strains belonging to 8 Leishmania species and evaluated on 75 human clinical skin samples., Findings: Sequence analysis showed 478 variable sites (302 being parsimony informative). Test of natural selection (dN-dS) (-0.164, SE = 0.013) inferred a negative selection, characteristic of essential genes, corroborating the DPPIII importance for parasite survival. Inter- and intra-specific genetic diversity was used to develop universal amplification of a 662bp fragment. Sequence analyses and phylogenies confirmed occurrence of 6 clusters congruent to L. major, L. tropica, L. aethiopica, L. arabica, L. turanica, L. tarentolae species, and one to the L. infantum and L. donovani species complex. A PCR-RFLP algorithm for Leishmania species identification was designed using double digestions with HaeIII and KpnI and with SacI and PvuII endonucleases. Overall, this PCR-RFLP yielded distinct profiles for each of the species L. major, L. tropica, L. aethiopica, L. arabica and L. turanica and the L. (Sauroleishmania) L. tarentolae. The species L. donovani, and L. infantum shared the same profile except for strains of Indian origin. When tested on clinical samples, the DPPIII PCR showed sensitivities of 82.22% when compared to direct examination and was able to identify 84.78% of the positive samples., Conclusion: The study demonstrates that DPPIII gene is suitable to detect and identify Leishmania species and to complement other molecular methods for leishmaniases diagnosis and epidemiology. Thus, it can contribute to evidence-based disease control and surveillance., Competing Interests: The authors have declared that no competing interests exist.

Tinea capitis (TC) is a common infectious disease throughout the world, mainly seen in children, but it can occur in adults. Even if mycological examination is essential to confirm the diagnosis, it has been proved that trichoscopy is a very effective useful tool in the screening of TC. Herein, we report two cases of adult TC with atypical clinical presentations causing a diagnostic delay of several years., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 International Journal of Trichology.)