RESUMEN
Coccidiomycosis is a potentially life-threatening fungal infection endemic to certain regions of Argentina. The infection is caused by Coccidioides spp. and is primarily diagnosed by Coccidioides antibody (Ab) detection. Access to rapid, highly accurate diagnostic testing is critical to ensure prompt antifungal therapy. The sona Coccidioides Ab Lateral Flow Assay (LFA) performs faster and requires less laboratory infrastructure and equipment compared with other Ab detection assays, potentially providing a substantial improvement for rapid case screening in coccidioidomycosis-endemic regions; however, validation of this test is needed. Thus, we aimed to evaluate the analytical performance of the sona Coccidioides Ab (LFA) and compare agreement with anti-Coccidioides Ab detection assays. A total of 103 human sera specimens were tested, including 25 specimens from patients with coccidioidomycosis and 78 from patients without coccidioidomycosis. The sona Coccidioides Ab Lateral Flow Assay (LFA) was performed with a sensitivity of 88%, and specificity and accuracy of 87%. Furthermore, the Coccidioides Ab LFA had good agreement with other anti-Coccidioides Ab detection assays. Our findings suggest the sona Coccidioides Ab LFA has satisfactory performance and may be useful for diagnosing coccidioidomycosis in endemic regions.
RESUMEN
Histoplasmosis is a worldwide systemic endemic mycosis caused by several cryptic species included within the Histoplasma capsulatum complex. Domestic and wild mammals are susceptible to infection by this fungus and could be used as indicators of its presence in the environment. The aim of the study was to identify the natural reservoirs of H. capsulatum in the Argentinean Humid Pampas eco-region analyzing a wildlife frozen-tissue collection and trace its distribution patterns over time and space. Tissue samples from 34 small wild mammals caught in the Humid Pampas were analyzed using two molecular markers: 100 kDa protein coding gene (Hcp100) and ITS1 rDNA. Results showed that 32.4% of them were infected with H. capsulatum and its DNA was detected in 5/17 Calomys laucha; 3/6 Calomys musculinus; 1/5 Akodon azarae, 1/3 Monodelphis dimidiata; and 1/2 Didelphis albiventris. In the single specimen studied of Cavia aperea, no H. capsulatum DNA was detected. This is the first H. capsulatum infection report in C. laucha and C. musculinus rodents and M. dimidiate opossum which proves that tissue collections are an important source of material for epidemiological studies of endemic disease over time.
Asunto(s)
Animales Salvajes/microbiología , Reservorios de Enfermedades/microbiología , Histoplasma/aislamiento & purificación , Histoplasmosis/epidemiología , Animales , Argentina/epidemiología , ADN de Hongos/genética , Enfermedades Endémicas , Estudios Epidemiológicos , Histoplasma/genética , Humanos , Bancos de Tejidos , Zoonosis/epidemiologíaRESUMEN
La histoplasmosis y la leishmaniasis son enfermedades olvidadas, endémicas en Argentina, y generalmente se asocian a inmunocompromiso. Presentamos el caso de un varón de 16 años, inmunocompetente, con histoplasmosis del sistema nervioso central y leishmaniasis cutánea. Inicialmente, el paciente presentó una lesión en la pierna de un mes de evolución seguida de paraparesia leve, diagnosticada como un proceso de desmielinización mediante estudios de imágenes. El cuadro fue tratado con altas dosis de corticoides y en 72 horas evolucionó a paraparesia grave con lesiones nodulares en las vértebras cervicales, observadas en las imágenes de resonancia magnética nuclear. Se aisló Histoplasma capsulatum de líquido cefalorraquídeo, genotípicamente identificado como perteneciente a la especie filogenética LamB. El paciente recibió tratamiento intravenoso con anfotericina B deoxicolato durante 30 días y posteriormente fluconazol e itraconazol oral durante un año. A los tres meses de iniciado el tratamiento con antifúngicos se reactivó la lesión de la pierna y en el examen directo se observaron amastigotes de Leishmania. La leishmaniasis cutánea fue tratada con antimoniato de meglumina intramuscular. La respuesta clínica al tratamiento de ambas enfermedades fue favorable.
Histoplasmosis and leishmaniasis are neglected and endemic diseases in Argentina, and generally are found associated with immunosuppression. We report the case of an immunocompetent 16-years-old man with simultaneous occurrence of central nervous system histoplasmosis and cutaneous leishmaniasis. Upon admission, the patient showed a one-month old skin lesion in a leg and mild paraparesis. Imaging studies detected thickening and edema in the spinal cord and the cerebrospinal fluid analysis was within normal range. The case was diagnosed as a demyelinating disorder and treated with high-dose short-term steroids. Seventy-two hours later the patient showed severe paraparesis and nuclear magnetic resonance imaging revealed nodular lesions in the spinal cord. Histoplasma capsulatum belonging to the phylogenetic species LamB was isolated from cerebrospinal fluid samples. The patient received intravenous antifungal therapy with amphotericin B for 30 days, followed by oral fluconazole and itraconazole for one year. Three months after initiation of antifungal treatment, the cutaneous lesion recrudesced and Leishmania amastigotes were observed on microscopic examination. The cutaneous leishmaniasis was treated with intramuscular meglumine antimoniate. The patient´s outcome was favorable after treatment for both diseases.
