RESUMEN
Antimonials remain the first-line treatment for the various manifestations of leishmaniasis in most areas where the disease is endemic, and increasing cases of therapeutic failure associated with parasite resistance have been reported. In this study, we assessed the molecular status of 47 clinical isolates of Leishmania causing visceral and cutaneous leishmaniasis from Algeria, Tunisia, and southern France. In total, we examined 14 genes that have been shown to exhibit significant variations in DNA amplification, mRNA levels, or protein expression with respect to resistance to antimonials. The gene status of each clinical isolate was assessed via qPCR and qRT-PCR. We then compared the molecular pattern against the phenotype determined via an in vitro sensitivity test of the clinical isolates against meglumine antimoniate, which is considered the reference technique. Our results demonstrate significant DNA amplification and/or RNA overexpression in 56% of the clinical isolates with the resistant phenotype. All clinical isolates that exhibited significant overexpression of at least 2 genes displayed a resistant phenotype. Among the 14 genes investigated, 10 genes displayed either significant amplification or overexpression in at least 1 clinical isolate; these genes are involved in several metabolic pathways. Moreover, various gene associations were observed depending on the clinical isolates, supporting the multifactorial nature of Leishmania resistance. Molecular resistance features were found in the 3 Leishmania species investigated (Leishmania infantum, Leishmania major, and Leishmania killicki). To our knowledge, this is the first report of the involvement of molecular resistance genes in field isolates of Leishmania major and Leishmania killicki with the resistance phenotype.
Asunto(s)
Antiprotozoarios/farmacología , Resistencia a Medicamentos/genética , Leishmania infantum/efectos de los fármacos , Leishmania major/efectos de los fármacos , Meglumina/farmacología , Compuestos Organometálicos/farmacología , Proteínas Protozoarias/genética , Argelia , Francia , Regulación de la Expresión Génica , Genotipo , Humanos , Leishmania infantum/genética , Leishmania infantum/aislamiento & purificación , Leishmania major/genética , Leishmania major/aislamiento & purificación , Leishmaniasis Cutánea/tratamiento farmacológico , Leishmaniasis Cutánea/parasitología , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/parasitología , Antimoniato de Meglumina , Redes y Vías Metabólicas/genética , Pruebas de Sensibilidad Parasitaria , Fenotipo , Proteínas Protozoarias/metabolismo , TúnezRESUMEN
This report describes the case of a 10-year-old boy with cutaneous leishmaniasis presumed to be caused by Leishmania major and successfully treated with oral azithromycin. Clinical studies using azithromycin for the treatment of cutaneous leishmaniasis are reviewed.
Asunto(s)
Azitromicina/uso terapéutico , Leishmaniasis Cutánea/tratamiento farmacológico , Niño , Humanos , MasculinoRESUMEN
Quantification of Leishmania infantum DNA in blood samples by an ultrasensitive quantitative polymerase chain reaction (QPCR) detected parasitemias in different clinical presentations. We observed a large range of parasitemias, more than 9 log values, and could determine the threshold between asymptomatic carriage and disease in the Mediterranean area (approximately one parasite/mL of blood). Based on kinetoplast DNA amplification, this assay had a sensitivity of 0.001 parasite DNA equivalents/mL and detected asymptomatic carriage of Leishmania. It detected parasite DNA in 58% of healthy subjects, while an immunoblot detected specific antibodies in only 16%. For initial diagnosis of disease, this quantitative PCR with blood samples constitutes a non-invasive alternative to bone marrow aspiration. Its main applications are monitoring of drug therapy and follow-up of immunodeficient patients for biologic confirmation of relapses.
Asunto(s)
Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/diagnóstico , Parasitemia/diagnóstico , Parasitemia/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Anfotericina B/uso terapéutico , Animales , ADN Protozoario/análisis , ADN Protozoario/sangre , Estudios de Seguimiento , Leishmania infantum/genética , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/parasitología , Parasitemia/sangre , Parasitemia/parasitología , Reacción en Cadena de la Polimerasa/métodos , Recurrencia , Valores de Referencia , Sensibilidad y EspecificidadRESUMEN
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%.
Asunto(s)
Leishmaniasis Visceral/etiología , Trasplante de Órganos/efectos adversos , Complicaciones Posoperatorias , Animales , Antiprotozoarios/uso terapéutico , Médula Ósea/parasitología , Humanos , Leishmania/aislamiento & purificación , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/tratamiento farmacológicoRESUMEN
BACKGROUND: Visceral leishmaniasis due to Leishmania infantum is currently spreading into new foci across Europe. Leishmania infantum transmission in the Old World was reported to be strongly associated with a few specific environments. Environmental changes due to global warming or human activity were therefore incriminated in the spread of the disease. However, comprehensive studies were lacking to reliably identify all the environments at risk and thereby optimize monitoring and control strategy. METHODOLOGY/FINDINGS: We exhaustively collected 328 cases of autochthonous visceral leishmaniasis from 1993 to 2009 in South-Eastern France. Leishmaniasis incidence decreased from 31 yearly cases between 1993 and 1997 to 12 yearly cases between 2005 and 2009 mostly because Leishmania/HIV coinfection were less frequent. No spread of human visceral leishmaniasis was observed in the studied region. Two major foci were identified, associated with opposite environments: whereas one involved semi-rural hillside environments partly made of mixed forests, the other involved urban and peri-urban areas in and around the region main town, Marseille. The two neighboring foci were related to differing environments despite similar vectors (P. perniciosus), canine reservoir, parasite (L. infantum zymodeme MON-1), and human host. CONCLUSIONS/SIGNIFICANCE: This unprecedented collection of cases highlighted the occurrence of protracted urban transmission of L. infantum in France, a worrisome finding as the disease is currently spreading in other areas around the Mediterranean. These results complete previous studies about more widespread canine leishmaniasis or human asymptomatic carriage. This first application of systematic geostatistical methods to European human visceral leishmaniasis demonstrated an unsuspected heterogeneity of environments associated with the transmission of the disease. These findings modify the current view of leishmaniasis epidemiology. They notably stress the need for locally defined control strategies and extensive monitoring including in urban environments.
Asunto(s)
Control de Enfermedades Transmisibles/métodos , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/transmisión , Topografía Médica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Francia/epidemiología , Humanos , Incidencia , Lactante , Leishmaniasis Visceral/prevención & control , Masculino , Persona de Mediana Edad , Población Rural , Población Urbana , Adulto JovenRESUMEN
OBJECTIVE: Leishmania infantum mucosally restricted leishmaniasis was rarely reported, so that diagnostic and treatment strategies remain debated. A long-term multicentric survey appeared thereby necessary. METHODS: Cases were prospectively collected over 12 years in 3 academic hospitals of Southern France. Predisposing factors, clinical findings, diagnostic procedures, treatment and outcome were compared to medical literature. RESULTS: Ten new cases and 40 historical reports were collected. Respectively 10/10 and 35/40 patients were adult males. Immunodeficiency was frequent (5/10 and 18/40). No previous cutaneous lesion was reported. Leishmaniasis affected mostly larynx (5/10 and 19/40), but also mouth (2/10 and 19/40) and nose (3/10 and 5/40). Lesions were highly polymorph. Mucosa histological examination provided respectively 1/10 and 2/40 false negative results, contrary to serum immunoblotting and PCR on mucosal biopsy. Although local response was always satisfactory even using topical treatment, subsequent visceral spreading was observed in 2/10 and 1/40 cases. CONCLUSION: L. infantum mucosally restricted leishmaniasis exhibits a specific pattern, marked by tropism for adult males, high clinical and histological polymorphism. Immunoblot screening and PCR confirmation of suspected lesions are necessary because of direct examination occasional false negative results. The risk of visceral spreading sustains systemic therapy. SUMMARY: Leishmania infantum mucosal leishmaniasis mostly affects adult males, half of them immunodeficient. Clinical and histological polymorphism makes the diagnosis difficult, stressing the need for immunoblot screening and mucosa PCR analysis of suspected cases. Possible visceralization sustains systemic therapy.
Asunto(s)
Leishmania infantum , Leishmaniasis Visceral/diagnóstico , Membrana Mucosa/parasitología , Centros Médicos Académicos , Adulto , Anciano , Anfotericina B/uso terapéutico , Antiprotozoarios/uso terapéutico , Femenino , Francia , Humanos , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Sistema de Registros , Sensibilidad y Especificidad , Distribución por Sexo , Resultado del Tratamiento , Adulto JovenRESUMEN
The diagnosis of disseminated toxoplasmosis in a 14-year-old allogeneic bone marrow recipient with graft-versus-host disease was determined by the detection of Toxoplasma gondii tachyzoites in sputum smears. Sputum analysis is a valuable alternative in the clinical assessment of pulmonary toxoplasmosis, especially when conventional invasive techniques are not practicable.
Asunto(s)
Enfermedades Pulmonares Parasitarias/diagnóstico , Esputo/parasitología , Toxoplasma/aislamiento & purificación , Toxoplasmosis/diagnóstico , Adolescente , Animales , Trasplante de Médula Ósea/efectos adversos , Femenino , Enfermedad Injerto contra Huésped/complicaciones , Humanos , Enfermedades Pulmonares Parasitarias/parasitología , Microscopía/métodos , Coloración y Etiquetado/métodos , Toxoplasma/crecimiento & desarrollo , Toxoplasmosis/parasitología , Trasplante Homólogo/efectos adversosRESUMEN
A real-time PCR was developed to quantify Leishmania infantum kinetoplast DNA and optimized to reach a sensitivity of 0.0125 parasites/ml of blood. In order to analyze the incidence of heterogeneity and number of minicircles, we performed comparative PCR by using the Leishmania DNA polymerase gene as a reporter. Assays performed in both promastigote and amastigote stages showed variations among different L. infantum and Leishmania donovani strains and the stability of the minicircle numbers for a particular strain. Analysis of blood samples from a patient who presented with Mediterranean visceral leishmaniasis confirmed the reliability of such an assay for Leishmania quantification in biological samples and allowed an estimation of positivity thresholds of classical tests used for direct diagnosis of the disease; positivity thresholds were in the range of 18 to 42, 0.7 to 42, and 0.12 to 22.5 parasites/ml for microscopic examination, culture, and conventional PCR, respectively. At the time of diagnosis, parasitemia could vary by a wide range (32 to 188,700 parasites/ml, with a median of 837 parasites/ml), while in bone marrow, parasite load was more than 100 parasites per 10(6) nucleated human cells. After successful therapy, parasitemia levels remain lower than 1 parasite/ml. In the immunocompromised host, relapses correlate with an increase in the level of parasitemia, sometimes scanty, justifying the need for assays with high sensitivity. Such sensitivity allows the detection of Leishmania DNA in the blood of 21% of patients with no history of leishmaniasis living in the Marseilles area, where leishmaniasis is endemic. This technique may be useful for epidemiologic and diagnostic purposes, especially for the quantification of parasitemia at low levels during posttherapy follow-up.