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Cutaneous leishmaniasis (CL) is firmly established in South America. We aimed to assess the detection of IgG antibodies against 14 and/or 16 kDa antigens by immunoblot (IB) for CL serological diagnosis in French Guiana, an area where many endemic pathogens could interfere with it. This study was performed retrospectively on sera from 141 patients at the Cayenne tertiary hospital: 30 were patients with confirmed CL, 71 were diagnosed with various other endemic pathogens, 11 were diagnosed with an autoimmune disease, and 29 controls had no history of CL. Antibodies bound to the 14 and/or 16 kDa antigens in 27 of the 30 CL patients’ sera and in 39 of the 111 non-CL patients’ sera (26 from the infectious diseases group, four from the autoimmune diseases group, and nine from the dermatology department). The method tested showed a high sensitivity (90%) and a low specificity (66%), and a diagnosis odds ratio of 17.5 (95% CI [4.6–78.0]). This IB may be helpful to exclude the diagnosis of CL, prompting physicians to look for another diagnosis in the case of a negative IB.

Background Zoonotic visceral leishmaniasis (VL) is endemic in the Mediterranean basin. However, large-scale comparative analyses of the commercial kits for the serological diagnosis of this neglected disease are lacking. This study compared the performances of four enzyme-linked immunosorbent assays (ELISA) and two immunochromatographic tests (ICT) as screening tests for the serodiagnosis of human VL in the Mediterranean region. Methodology/Principal findings Serum samples from 319 patients living in France, Tunisia or Morocco were tested using two ICT (IT LEISH and TruQuick LEISH IgG/IgM Meridian) and four ELISA reagents (NovaLisa Leishmania infantum IgG, Bordier Leishmania infantum, Ridascreen Leishmania IgG, and Vircell Leishmania). The population with proven VL (n = 181) included 65 immunocompromised patients. Significantly higher percentages of false-negative results were obtained with all assays in immunocompromised patients, compared with the immunocompetent population. In the whole population, sensitivity and specificity ranged from 80.7% to 93.9% and from 95.7% to 100%, respectively. The maximum accuracy was observed with the Bordier and Vircell ELISA kits (96.2%), and the lowest accuracy with Ridascreen reagent (88.7%). New thresholds of positivity are proposed for the Bordier, Vircell and NovaLisa ELISA kits to achieve 95% sensitivity with the highest possible specificity. Western blot (WB), used as a confirmation method, showed 100% sensitivity and identified 10.1% of asymptomatic carriers among the control population from the South of France. Conclusions/Significance This is the first study that compared commercially available kits for VL serodiagnosis in the endemic region of the Mediterranean basin. It provides specific information about the tests’ performance to help clinicians and biologists to select the right assay for VL screening., Author summary Human visceral leishmaniasis (VL) is a neglected disease endemic in the Mediterranean region, caused by Leishmania infantum. Accurate VL diagnosis is critical for rapid and correct patient management. Various serological tests are used, including commercial kits that require qualifications with specific information about their performance. In this study, we compared the performance of six commercial kits, two immunochromatographic tests (ICT; IT LEISH and TruQuick LEISH IgG/IgM Meridian) and four enzyme-linked immunosorbent assays (ELISA; NovaLisa Leishmania infantum IgG, Bordier Leishmania infantum, Ridascreen Leishmania IgG, and Vircell Leishmania), available in France and used as screening tests. The Bordier and Vircell ELISA reagents displayed the highest analytic performance compared with all the other kits. However, no test displayed 95% sensitivity at the thresholds recommended by the manufacturers. To reach this sensitivity value with the highest possible specificity, new thresholds are proposed for the Bordier, Vircell and NovaLisa ELISA reagents. Positive and negative results obtained with the six screening tests were confirmed by Western blot (100% sensitivity). Overall, this study presents a comparative analysis of commercially available kits for the serodiagnosis of human VL and provides additional information on the prevalence of asymptomatic carriers in the Mediterranean basin.

There is a scarcity of recent epidemiological data on intestinal parasitic infections in France. We conducted a prospective study aimed at estimating the prevalence of 10 enteric parasites in Marseille, France, using real-time polymerase chain reaction (PCR)-based diagnosis. A total of 643 faeces from 488 patients referred to the Parasitology-Mycology Laboratory of the University Hospital of Marseille over a 6 months period were included. DNA was extracted using a semi-automated method. Parasites of interest were detected using singleplex quantitative PCRs (qPCRs). For positive samples, theBlastocystissubtype was determined by sequence analysis. During the study, the overall prevalence of enteric parasites was 17%.Blastocystis sp.was the most frequent species (10.5%), followed byDientamoeba fragilis(2.3%) andGiardia intestinalis(2.3%). The prevalence of other parasites was Blastocystissubtype was predominant (43.6%) and the other subtypes identified were ST1, ST2, ST4 and ST6. This is the first time that a qPCR-based diagnosis has been used to survey the prevalence of 10 enteric parasites in a French University Hospital. This study confirms that fast, specific, sensitive and simultaneous detection in a single stool sample by qPCR clearly outperforms conventional microscopy-based diagnosis. Furthermore, qPCR is particularly well suited to surveying gastroenteritis agents.

Objective Efficient and easy-to-use DNA extraction and purification methods are critical in implementing PCR-based diagnosis of pathogens. In order to optimize the routine clinical laboratory diagnosis of eukaryotic enteric pathogens, we compare, via quantitative PCR cycle threshold (Ct) values, the efficiency of two DNA extraction kits: the semi-automated EZ1® (Qiagen) and the manual QIAamp® DNA Stool Mini Kit (Qiagen), on six protozoa: Blastocystis spp., Cryptosporidium parvum/hominis, Cyclospora cayetanensis, Dientamoeba fragilis, Giardia intestinalis and Cystoisospora belli and one microsporidia: Enterocytozoon bieneusi. Results Whereas EZ1® (Qiagen) and QIAamp® DNA Stool Mini Kit (Qiagen) yielded similar performances for the detection of Cryptosporidium spp. and D. fragilis, significant lower Ct values (p

International audience; Key Clinical Message Images of parasitic forms of Leishmania infantum are typical in the hands of a skilled expert but should be known by biologists of Hematology Department. In an endemic region, the diagnosis of visceral leishmaniasis (VL) must be considered because of its potential role in accelerating hematological malignancy.

In both the post and pre combination antiretroviral therapy (cART) era, Pneumocystis jirovecii and Toxoplasma gondii remain common opportunistic infectious agents. The common manifestations are pneumonia for P. jirovecii and brain abscess for T. gondii. Nevertheless, co-infection remains rare, and pulmonary toxoplasmosis is scarce, or may be underestimated because of its similarity with Pneumocystis jirovecii pneumonia. We reported an uncommon case of an AIDS patient (6 CD4 + T cells/mm³) with both pulmonary and cerebral toxoplasmosis associated with pneumocystis pneumonia. The patient presented with general weakness, fever and dyspnea. Pulmonary toxoplasmosis and pneumocystis were confirmed by microscopic examination and DNA detection in the bronchoalveolar lavage. Computed tomography imaging of the brain revealed a single characteristic cerebral toxoplasmosis lesion of the left capsular area. He was successful treated by trimethoprim/sulfamethoxaxole in conjunction with an early reintroduction of cART, and without IRIS development. During a 3-year follow-up, HIV viral load remained undetectable, and the patient did not relapse for toxoplasmosis or Pneumocystis pneumonia.

Leishmaniasis is considered a rural disease in Europe. However, circumstantial evidence has indicated urban transmission of leishmaniasis and phleboviruses in the urban area of Marseille, France. To investigate this urban transmission, sandflies were trapped in 33 locations in the urban area (horse farms, public gardens and a residential area). Sandflies were always captured: 87.8% were Phlebotomus perniciosus, a vector of Leishmania infantum and Toscana and Massilia viruses. RT-PCR and cell culture inoculation identified the Massilia virus in 2/99 pools of sandflies, and PCR identified Leishmania in 5/99. No dual infection was observed, but both pathogens were detected in samples from the same trapping site.

Leishmania parasites induce an immunomodulation by subverting the host immune response towards a CD4+Th2 lymphocytic cell response that favors parasite persistence. Here, we report that after successful treatment of visceral leishmaniasis due to Leishmania infantum, an immune reconstitution syndrome revealing hip septic arthritis was associated with a switch from Th2 towards a Th1 cytokine profile, and a decrease in the level of immunomodulating factors, such as soluble HLA-G and indoleamine 2,3-dioxygenase (IDO) activity. We then measured IDO activity in a cohort of 39 patients and uninfected control subjects. Results showed significantly enhanced IDO activity in patients with visceral Leishmania infection, compared with uninfected control subjects ( P

The role of red foxes in the natural cycle of Leishmania infection is not well known. In the Var area, southeastern France, from 2006 to 2012, we conducted a longitudinal epidemiologic survey of foxes using quantitative PCR. Among 92 red foxes screened, prevalence of Leishmania infantum infection was 9%. Red foxes may be considered a bioindicator of parasite circulation in this biotope.

AA-amyloidosis in the setting of chronic visceral leishmaniasis (VL) has been reported in animal models but documentation in humans is unavailable. Here, we report on a Portuguese man who in 1996 was diagnosed with both human immunodeficiency virus (HIV)-infection and VL. Antiretroviral treatment led to sustained suppression of HIV viremia but CD4+ lymphocytes rose from 8 to only 160 cells/mL. Several courses of antimony treatment did not prevent VL relapses. Renal failure developed in 2006 and renal biopsy revealed AA-amyloidosis. The patient had cryoglobulinemia and serum immune complexes containing antibodies directed against seven leishmanial antigens. Antimony plus amphotericin B, followed by oral miltefosine resulted in a sustained VL treatment response with elimination of circulating Leishmania infantum DNA and CD4+ recovery. The concomitant reduction of serum AA levels and disappearance of circulating leishmanial immune complexes suggests that prolonged VL may lead to AA-amyloidosis in immunocompromised humans.

Human and animal fungal pathogens are a growing threat worldwide leading to emerging infections and creating new risks for established ones. There is a growing need for a rapid and accurate identification of pathogens to enable early diagnosis and targeted antifungal therapy. Morphological and biochemical identification methods are time-consuming and require trained experts. Alternatively, molecular methods, such as DNA barcoding, a powerful and easy tool for rapid monophasic identification, offer a practical approach for species identification and less demanding in terms of taxonomical expertise. However, its wide-spread use is still limited by a lack of quality-controlled reference databases and the evolving recognition and definition of new fungal species/complexes. An international consortium of medical mycology laboratories was formed aiming to establish a quality controlled ITS database under the umbrella of the ISHAM working group on "DNA barcoding of human and animal pathogenic fungi." A new database, containing 2800 ITS sequences representing 421 fungal species, providing the medical community with a freely accessible tool at http://www.isham.org and http://its.mycologylab.org/ to rapidly and reliably identify most agents of mycoses, was established. The generated sequences included in the new database were used to evaluate the variation and overall utility of the ITS region for the identification of pathogenic fungi at intra-and interspecies level. The average intraspecies variation ranged from 0 to 2.25%. This highlighted selected pathogenic fungal species, such as the dermatophytes and emerging yeast, for which additional molecular methods/genetic markers are required for their reliable identification from clinical and veterinary specimens., This study was supported by an National Health and Medical Research Council of Australia (NH&MRC) grant [#APP1031952] to W Meyer, S Chen, V Robert, and D Ellis; CNPq [350338/2000-0] and FAPERJ [E-26/103.157/2011] grants to RM Zancope-Oliveira; CNPq [308011/2010-4] and FAPESP [2007/08575-1] Fundacao de Amparo Pesquisa do Estado de So Paulo (FAPESP) grants to AL Colombo; PEst-OE/BIA/UI4050/2014 from Fundacao para a Ciencia e Tecnologia (FCT) to C Pais; the Belgian Science Policy Office (Belspo) to BCCM/IHEM; the MEXBOL program of CONACyT-Mexico, [ref. number: 1228961 to ML Taylor and [122481] to C Toriello; the Institut Pasteur and Institut de Veil le Sanitaire to F Dromer and D Garcia-Hermoso; and the grants from the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) and the Fundacao de Amparo a Pesquisa do Estado de Goias (FAPEG) to CM de Almeida Soares and JA Parente Rocha. I Arthur would like to thank G Cherian, A Higgins and the staff of the Molecular Diagnostics Laboratory, Division of Microbiology and Infectious Diseases, Path West, QEII Medial Centre. Dromer would like to thank for the technical help of the sequencing facility and specifically that of I, Diancourt, A-S Delannoy-Vieillard, J-M Thiberge (Genotyping of Pathogens and Public Health, Institut Pasteur). RM Zancope-Oliveira would like to thank the Genomic/DNA Sequencing Platform at Fundacao Oswaldo Cruz-PDTIS/FIOCRUZ [RPT01A], Brazil for the sequencing. B Robbertse and CL Schoch acknowledge support from the Intramural Research Program of the NIH, National Library of Medicine. T Sorrell's work is funded by the NH&MRC of Australia; she is a Sydney Medical School Foundation Fellow., info:eu-repo/semantics/publishedVersion

Eleven new cases of visceral leishmaniasis (VL) are reported in organ transplant patients in France. The epidemiological, clinical, biological, diagnostic and therapeutic features are reviewed, based on these cases and 46 cases reported in the literature. VL was most commonly associated with renal transplantation (77% of the cases). Most patients were from Southern European countries. The main clinical symptom was fever. Leucopoenia and anaemia were the most frequent haematological disorders. Diagnosis was by direct finding of the parasite in smears of bone marrow (85.2%) or, by positive serology (90.9%). Without antileishmanial treatment, VL in transplant recipients was fatal. Treatment using either antimonials or amphotericine B gave similar cure rates of around 80% of the cases. But toxicity was higher for antimonials. Relapses occurred in 14.3%.

A 3-year longitudinal survey was carried out from 1998 to 2000 in a village in eastern Sudan where a visceral leishmaniasis (VL) outbreak occurred. Leishmania-specific antibodies were analysed by enzyme-linked immunosorbent assay and immunoblotting. Immunoblot analysis detected antibodies to Leishmania in 80% of the healthy subjects and half of them harboured high immunoglobulin (Ig) G antibody levels, similar to those of VL patients. These antibodies belonged to the IgG1 and IgG3 subclasses but neither their respective levels nor the immunoblot recognition patterns were predictive of VL. During this epidemic, a large proportion of subjects had a high antileishmanial antibody response, indicating that they were infected by Leishmania though most of them remained healthy during the whole study period. These results obtained in the context of an outbreak contrast with those obtained from studies performed in endemic areas characterized by lower parasite transmission levels. Furthermore, the clinical and serological follow-up of our study subjects showed that VL occurred mainly in subjects who had been serologically positive for 5-24 months rather than resulting from primo infection by the parasite.