Setting up regional diagnostic reference levels for pediatric computed tomography in Latin America: preliminary results, challenges and the work ahead.

We established a framework for collecting radiation doses for head, chest and abdomen-pelvis computed tomography (CT) in children scanned at multiple imaging sites across Latin America with an aim towards establishing diagnostic reference levels (DRLs) and achievable doses (ADs) in pediatric CT in Latin America. Our study included 12 Latin American sites (in Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Honduras and Panama) contributing data on the four most common pediatric CT examinations (non-contrast head, non-contrast chest, post-contrast chest and post-contrast abdomen-pelvis). Sites contributed data on patients' age, sex and weight, scan factors (tube current and potential), volume CT dose index (CTDIvol) and dose length product (DLP). Data were verified, leading to the exclusion of two sites with missing or incorrect data entries. We estimated overall and site-specific 50th (AD) and 75th (diagnostic reference level [DRL]) percentile CTDIvol and DLP for each CT protocol. Non-normal data were compared using the Kruskal-Wallis test. Sites contributed data from 3,934 children (1,834 females) for different CT exams (head CT 1,568/3,934, 40%; non-contrast chest CT 945/3,934, 24%; post-contrast chest CT 581/3,934, 15%; abdomen-pelvis CT 840/3,934, 21%). There were significant statistical differences in 50th and 75th percentile CTDIvol and DLP values across the participating sites (P<0.001). The 50th and 75th percentile doses for most CT protocols were substantially higher than the corresponding doses reported from the United States of America. Our study demonstrates substantial disparities and variations in pediatric CT examinations performed in multiple sites in Latin America. We will use the collected data to improve scan protocols and perform a follow-up CT study to establish DRLs and ADs based on clinical indications.

Giant cavernous malformation of the posterior fossa with lymphangiomatous phenotype, associated with orbital venolymphatic anomaly in an 11-month-old patient: case report and literature review.

The synchronous presentation of venolymphatic anomalies of the orbit and noncontiguous intracranial cavernous malformations is uncommon. Herein, we present a case of an 11-month-old female patient diagnosed with orbital venolymphatic anomaly associated with a large cavernous malformation in the posterior fossa, who underwent complete surgical resection of the latter. The immunohistochemical analysis was positive for podoplanin, a marker expressed by lymphatic endothelial cells, but not vascular endothelium. This exceptional finding suggests lymphatic involvement in the etiology of the lesion. In our review of the literature, we did not find similar cases in patients under 1 year of age.

Primary Central Nervous System Lymphoma in a Patient on Adalimumab Therapy for Chronic Plaque Psoriasis.

BACKGROUND: Adalimumab (Humira) is a recombinant human monoclonal antibody against tumor necrosis factor alpha, which works by blocking the interaction of tumor necrosis factor alpha with its cell-surface receptors, thereby limiting the progression of inflammatory pathways. Its use is approved for several autoimmune conditions, including chronic plaque psoriasis, for which it has been prescribed as a first-line biologic treatment. Increased risks of malignancy, particularly nonmelanoma skin cancer and non-central nervous system lymphomas, have been reported with use of this drug; however, there have been no reports of central nervous system lymphomas. CASE DESCRIPTION: A 43-year-old man presented for evaluation following recent speech difficulty and a generalized tonic-clonic seizure. His medical history was significant for plaque psoriasis, for which he had been receiving treatment with adalimumab for 4 months. Magnetic resonance imaging scan of the brain with contrast agent showed a well-defined rounded enhancing lesion in the left temporal lobe with circumferential vasogenic edema. Mass effect was noted. Computed tomography scan of the chest, abdomen, and pelvis was unremarkable. He underwent excisional biopsy, and the preliminary intraoperative pathology report revealed a diagnosis of high-grade lymphoma. Subsequent analysis of morphology and immunophenotyping was consistent with primary diffuse large B-cell lymphoma of the central nervous system. Use of adalimumab was discontinued. Following combination therapy with high-dose methotrexate and rituximab along with 20 sessions of cranial radiation therapy, the patient was disease-free at 14-month follow-up. CONCLUSIONS: We report the first case to our knowledge showing a possible association of central nervous lymphoma and adalimumab.

Evaluación bacteriológica de infecciones en niños por Staphylococcus aureus / Bacteriological evaluation of infections caused by Staphylococcus aureus in children

El staphylococcus aureus (SA) a pesar de los grandes avances en microbiología y terapéutica anti-infecciosa continúa ocasionando morbilidad y letalidad por su frecuencia y capacidad de desencadenar resistencia a los antimicrobianos. Evaluar describir y analizar los aislamientos bacteriológicos de Staphylococcus aureus procedentes de niños infectados, atendidos en el Hospital Universitadrio de Caracas y revisar las variaciones que están ocurriendo en sus patrones de sensibilidad antimicrobiana. Estudio de vigilancia bacteriológica efectuado en la Sección de Bacteriología. Diariamente se revisaban los cultivos procesados y se seleccionaban los aislamientos de SA con su sensibilidad antimocrobiana. Posteriormente los aislamientos de SA se relacionaban con los antecedentes demográficos de los niños. Se incluyeron 37 aislamientos de SA procedentes de igual número de pacientes, 51 por ciento del sexo masculino. Al servicio de Pediatría Médica pertenecía el 41 por ciento de los pacientes y al de Pediatría Médica Infecciosa el 30 por ciento. De piel y tegumentos se aisló el 55 por ciento de las bacterias y de sangre el 34 por ciento. Sensibilidad antimicrobiana: vancomicina, oxacilina y clindamicina 100 por ciento, eritromicina 95 por ciento. Las infecciones por SA continúan afectando la piel y tegumentos de los niños que ingresan al Hospital Universitario y eventualmente causan bacteriemias y sepsis. La bacteria sigue siendo muy estable a los antimicrobianos de relevancia para su tratamiento en esta institución asistencial