Confirmation of rubella within 4 days of rash onset: comparison of rubella virus RNA detection in oral fluid with immunoglobulin M detection in serum or oral fluid.

Rubella virus infection is typically diagnosed by the identification of rubella virus-specific immunoglobulin M (IgM) antibodies in serum, but approximately 50% of serum samples from rubella cases collected on the day of rash onset are negative for rubella virus-specific IgM. The ability to detect IgM in sera and oral fluids was compared with the ability to detect rubella virus RNA in oral fluids by reverse transcription-PCR (RT-PCR) by using paired samples taken within the first 4 days after rash onset from suspected rubella cases during an outbreak in Perú. Sera were tested for IgM by both indirect and capture enzyme immunoassays (EIAs), and oral fluids were tested for IgM by a capture EIA. Tests for IgM in serum were more sensitive for the confirmation of rubella than the test for IgM in oral fluid during the 4 days after rash onset. RT-PCR confirmed more suspected cases than serum IgM tests on days 1 and 2 after rash onset. The methods confirmed approximately the same number of cases on days 3 and 4 after rash onset. However, a few cases were detected by serum IgM tests but not by RT-PCR even on the day of rash onset. Nine RT-PCR-positive oral fluid specimens were shown to contain rubella virus sequences of genotype 1C. In summary, RT-PCR testing of oral fluid confirmed more rubella cases than IgM testing of either serum or oral fluid samples collected in the first 2 days after rash onset; the maximum number of confirmations of rubella cases was obtained by combining RT-PCR and serology testing.

Dried blood spots versus sera for detection of rubella virus-specific immunoglobulin M (IgM) and IgG in samples collected during a rubella outbreak in Peru.

Most persons with rubella virus-specific immunoglobulin M (IgM)- or IgG-positive sera tested positive (98% [n = 178] and 99% [n = 221], respectively) using paired filter paper dried blood spot (DBS) samples, provided that DBS indeterminate results were called positive. For persons with IgM- or IgG-negative sera, 97% and 98%, respectively, were negative using DBS.

Loxocelismo en niños hospitalizados, Perú, 1970- 1990 / Loxocelism in hospitalized children, Peru, 1970-1990

Objetivo: Describir las características clínicas de los casos de loxocelismo en niños. Material y métodos: Estudio descriptivo retrospectivo, que incluye a todos los niños hospitalizados con diagnóstico de alta de loxoscelismo en el servicio de Pediatría del Hospital Nacional Cayetano Heredia entre 1970 y 1990, y los servicios de Medicina, Cirugía y Nefrología del Instituto Nacional de Salud del Niño entre 1980 y 1990, Lima-Perú. Resultados: Se incluyeron 89 casos (56.1% varones), el grupo más afectado (38.2%) tenía entre 5 y 10 años. Las regiones corporales comprometidas en orden de frecuencia fueron cabeza y el cuello (32.6%), miembros superiores (26.9%) e inferiores (23.6%), tórax y abdomen (12.4%) y genitales (4.5%). Los primeros signos y síntomas se presentaron durante las primeras 24 a 48 horas del accidente. Las complicaciones sistémicas más importantes fueron anemia hemolítica (49.4%) e insuficiencia renal aguda (37.1%). El 43.8% presentó la forma cutánea y el 56.2% la víscero-hemolítica (18.0% de letalidad para esta forma). La mortalidad fue mayor en niños menores de un año. Conclusiones: La presentación de sintomatología fluctúa entre las 24 a 48 horas siguientes a la mordedura. La forma víscero-hemolítica no fue un evento infrecuente. El único factor de riesgo aparente para mortalidad fue tener una edad menor de un año (AU)

Objective:To describe the clinical features of loxoscelism in children. Methods: Retrospective descriptive study, that included all children admitted as in-patients because of loxocelism at the Hospital Nacional Cayetano Heredia from 1970 to 1990, and at Instituto de Salud del Niño between 1980 to 1990 in Lima-Peru.The clinical files were reviewed. Results:89 were included (56.1% males).The most affected age-group (38.2%) was between 5 and 10 years old.The most frequently affected areas of the body were: head and neck (32.6%), upper extremities (26.9%), inferior extremities (23.6%) thorax and abdomen (12.4%) and genitals (4.5%).The first signs and symptoms appeared during the first 24 to 48 hours of the accident.The most important systemic complications were hemolytic anemia (49.4%) and acute renal failure (37.1%). 43.8% of patients presented the cutaneous form and 56.2% the visceral-hemolytic (18% of lethality). Mortality was greater in smaller children. Conclusions: The onset of disease fluctuates between 24 and 48 hours following the bite. The visceralhemolytic form was infrequent.The sole apparent risk factor for mortality was age less than one year old (AU)

Clinical evaluation of a 16S ribosomal RNA polymerase chain reaction test for the diagnosis of lymph node tuberculosis.

UNLABELLED: Reports on the sensitivity of polymerase chain reaction (PCR) for the diagnosis of lymph node tuberculosis (TB) show divergent results. We evaluated the accuracy of the Roche Amplicor Mycobacterium tuberculosis PCR test with lymph node aspirate and biopsy samples. METHODS: The study was conducted at a public reference hospital in Lima, Peru. From the period of January 2003 to January 2004, we included patients who had lymphadenopathy and in whom the attending physician suspected TB. Aspirate and biopsy samples were submitted for culturing in Lowenstein-Jensen medium, for histopathologic testing, and for PCR. The sensitivity and specificity of PCR were calculated against a reference standard based on histopathologic findings and culture. RESULTS: Our study included 154 patients. Median age was 29 years (interquartile range, 21-40 years); 97 patients (62.9%) were men. Twenty-nine patients (18.8%) had acid fast bacilli-positive histopathologic findings, and 44 (28.6%) had a positive culture result. Using the combination of histopathologic findings and culture as reference standard, 55 patients (35.7%) had a diagnosis of tuberculous lymphadenitis. The sensitivity of the PCR test was 58.2%, and the specificity was 93.9%. For biopsy tissue only, the sensitivity of PCR was 52.7%, and the specificity was 97.0%. For aspirate samples only, the sensitivity of PCR was 47.3%, and the specificity was 96.0%. CONCLUSION: The Amplicor PCR test revealed low sensitivity and high specificity for the diagnosis of lymph node TB. The sensitivity was higher in cases in which the bacillary load was high--in acid fast bacilli-positive samples and among HIV-infected patients. Considering the results of microbiological and PCR tests together, there was still a patient group in whom no final diagnosis could be established.

Enfermedades por ectoparasitos: Segunda parte / Ectoparasites diseases: Second part

Se presenta una revisión en aspectos clínicos y epidemiológicos de los principales ectoparásitos: piojos (pediculosis), moscas (myasis), pulgas (pulicosis y tungiasis), chinches (cimicosis), acarosis (sarna o escabiosis), picadura de abejas, avispas y hormigas y del erucismo.

Estudio prospectivo de la verruga peruana recurrente / Prospective study of recurrent peruvian verruga

Introducción: La verruga peruana recurrente es un evento raro que se caracteriza por recurrencia de un brote eruptivo verrucoso tiempo después de episodio inicial. Objetivo: Demostrar la existencia de formas recurrentes de verruga peruana en personas nativas y foráneas de zonas endémicas. Material y Métodos: Pacientes regstrados en el Departamento de Enfermedades Transmisibles y Dermatológicas del Hospital Nacional Cayetano Heredia con cuadro clínico de verruga peruana, desde 1980 hasta noviembre de 2003. Resultados: De los 137 pacientes estudiados con verruga peruana se encontraron siete con forma recurrente, la mayoría de los 137 pacientes tenían lesiones miliares, 70 por ciento eran menores de 15 años, 20 por ciento provenían de zonas endémicas. Los pacientes fueron tratados con Rifampicina, Ciprofloxacina, Azitromicina o Eritromicina. Conclusiones: De los siete pacientes encontrados con verruga peruana recurrente dos eran originarios de zonas endémicas y cinco fueron foráneos, éstos últimos no retornaron a las zonas prevalentes, lo cual nos afirma la existencia de estados latentes de Batonella bacilliformes en algunos tejidos aún no precisados, que debe ser motivo para investigar.

Enfermedad de Kikuchi-Fujimoto, tuberculosis ganglionar y tuberculide, comunicación de casos y revisión de literatura / Disease of Kikuchi-Fujimoto, tuberculosis, lymph node and tuberculide, communication of cases and review of literature

Se comunican dos casos de tuberculosis ganglionar que simulan histológicamente la enfermedad de Kikuchi, es decir, un patrón de linfadenitis histiocítica necrotizante. Uno de ellos presentó, además, cambios clínicos e histológicos de la tuberculide rosaceiforme de Lewandowsky, lo que demuestra que esta última entidad puede excepcionalmente ser una verdadera tuberculide.