RESUMEN
Cystic bone lesions are the hallmark of skeletal abnormalities in patients with congenital generalized lipodystrophy (CGL). However, their pathophysiology is still unclear and theories about their origin remain largely speculative. This article reports on a patient with CGL and cystic bone lesions, some of them with unusual magnetic resonance imaging (MRI) findings that include elevated signal intensity on T1-weighted images and fluid-fluid levels, the latter evolving to a more "classic" cystic appearance on follow-up. Even though similar findings were first described almost 30 years ago, little attention was given to them back then; furthermore, other than the present report, no other study has performed sequential exams to follow their evolution in serial MRI. The authors conduct a review of the literature, hypothesizing that these remarkable findings may reflect an intermediate stage in the process of cystification of the abnormal bone marrow, incapable to perform adipose conversion, lending factual support to the modern theories about this issue.
Asunto(s)
Lipodistrofia Generalizada Congénita , Humanos , Lipodistrofia Generalizada Congénita/complicaciones , Imagen por Resonancia Magnética , Tejido Adiposo/diagnóstico por imagenRESUMEN
Senecavirus A (SVA) belonging to the family Picornaviridae, genus Senecavirus was incidentally isolated in 2002 from the PER.C6 (transformed foetal retinoblast) cell line. However, currently, this virus is associated with vesicular disease in swine and it has been reported in countries such as the United States of America, Canada, China, Thailand and Colombia. In Brazil, the SVA was firstly reported in 2015 in outbreaks of vesicular disease in swine, clinically indistinguishable of Foot-and-mouth disease, a contagious viral disease that generates substantial economic losses. In the present work, it was standardized a diagnostic tool for SVA based on RNA reverse transcriptase droplet digital PCR (RT-ddPCR) using one-step and two-step approaches. Analytical sensitivity and specificity were done in parallel with real-time PCR, RT-qPCR (one-step and two-step) for comparison of sensitivity and specificity of both methods. In the standardization of RT-ddPCR, the double-quenched probe and the temperature gradient were crucial to reduce background and improve amplitude between positive and negative droplets. The limit of detection and analytical specificity of techniques of one-step techniques showed superior performance than two-step methods described here. Additionally, the results showed 94.2% concordance (p < 0.001) for RT-ddPCR and RT-qPCR using the one-step assay approach and biological samples from Brazilian outbreaks of Senecavirus A. However, ddRT-PCR had a better performance than RT-PCR when swine serum pools were tested. According to the results, the one-step RT-ddPCR and RT-qPCR is highlighted to be used as an auxiliary diagnostic tool for Senecavirus A and for viral RNA absolute quantification in biological samples (RT-ddPCR), being a useful tool for vesicular diseases control programs.
Asunto(s)
Enfermedades Transmisibles Emergentes/veterinaria , Brotes de Enfermedades/veterinaria , Infecciones por Picornaviridae/veterinaria , Picornaviridae/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Enfermedades de los Porcinos/epidemiología , Animales , Brasil/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/virología , Enterovirus Humano B/genética , Enterovirus Humano B/aislamiento & purificación , Picornaviridae/genética , Infecciones por Picornaviridae/epidemiología , Infecciones por Picornaviridae/virología , ARN Viral/análisis , Sensibilidad y Especificidad , Porcinos , Enfermedades de los Porcinos/virología , Enfermedad Vesicular Porcina/epidemiología , Enfermedad Vesicular Porcina/virologíaRESUMEN
Despite the worldwide occurrence of Francisella noatunensis subsp. orientalis (Fno) infection in farmed tilapia, sensitivity and specificity estimates of commonly used diagnostic tests have not been reported. This study aimed to estimate the sensitivity and specificity of bacteriological culture and qPCR to detect Fno infection. We tested 559 fish, sampled from four farms with different epidemiological scenarios: (i) healthy fish in a hatchery free of Fno; (ii) targeted sampling of diseased fish with suggestive external clinical signs of francisellosis during an outbreak; (iii) convenience sampling of diseased and clinically healthy fish during an outbreak; and (iv) sampling of healthy fish in a cage farm without a history of outbreaks, but with francisellosis reported in other farms in the same reservoir. The qPCR had higher median sensitivity (range, 48.8-99.5%) than culture (range, 1.6-74.4%). Culture had a substantially lower median sensitivity (1.6%) than qPCR (48.8%) to detect Fno in carrier tilapia (farm 4). Median specificity estimates for both tests were >99.2%. The qPCR is the superior test for use in surveillance and monitoring programmes for francisellosis in farmed Nile tilapia, but both tests have high sensitivity and specificity which make them fit for use in the diagnosis of Fno outbreaks.