Mutations in PIK3R1 can lead to APDS2, SHORT syndrome or a combination of the two.

Mutations in PIK3R1 gene have been associated to two different conditions: a primary immunodeficiency, called APDS2, of recent description and SHORT syndrome. 47 patients with APDS2 have been reported to date, only one of them sharing both PIK3R1-related phenotypes. Here we describe two more patients affected by APDS2 and SHORT syndrome, which highlights that this association may not be so infrequent. We recommend that patients with mutations in PIK3R1 gene should be assessed by both clinical immunologists and clinical geneticists.

[Reversible posterior leukoencephalopathy: report of two cases after vincristine treatment]. / Leucoencefalopatía posterior reversible: descripción de dos casos asociados a vincristina.

Reversible posterior leukoencephalopathy syndrome is a clinical-radiological phenomenon associated with headache, vomiting, lethargy, visual disturbances and seizures, concomitant with radiological abnormalities predominantly within posterior cerebral white matter due to cerebral edema. There are multiple triggers as acute hypertension, cancer, hematological disease, renal pathology, red cells transfusions and different drugs. We present two patients with reversible posterior leukoencephalopathy under treatment for acute lymphoblastic leukemia because of the probable association with vinca alkaloids.

[Pheochromocytoma and paraganglioma in childhood: a report of 2 cases report]. / Feocromocitoma y paraganglioma en la infancia: a propósito de 2 casos.

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors in children and most of them are sporadic. However, they represent the most common endocrine tumor in childhood, and hereditary tumor syndromes are most relevant in these age. Advances in genetic, biochemistry and imaging techniques have revised the management of these tumors; thus A biochemical study should be always initiated once the clinical diagnosis is suspected, followed by imaging and molecular studies, particularly in the context of known familial disease. The diagnostic and therapeutic features are reviewed after the presentation of two clinical cases, where the second one is a patient with type 1 Neurofibromatosis.

[Posterior reversible encephalopathy syndrome: 5 chemotherapy related cases]. / Síndrome de encefalopatía posterior reversible: 5 casos relacionados con quimioterapia.

Posterior reversible encephalopathy syndrome, previously known as Reversible posterior leukoencephalopathy syndrome, is a clinical-radiological condition characterized by headache, altered mental functioning, seizures and visual alterations, with the magnetic resonance imaging showing cerebral edema, predominantly in the white matter with posterior distribution. Multiple clinical conditions can act as triggers. We present five oncology patients, four of them with acute lymphoblastic leukemia, receiving chemotherapy when they presented with this pathology. A prompt diagnosis, an appropriate therapy for hypertension, and a rapid control of the seizures are the keys to avoiding sequelae.

[Update on L-asparaginase treatment in paediatrics]. / Actualización del tratamiento con L-asparraginasa en Pediatría.

L-asparaginase (L-ASP) is one of the cornerstones of the treatment of acute lymphoblastic leukemia and non-Hodgkin lymphoma. It is an enzyme of bacterial origin capable of transforming L-asparagine to aspartic acid. The extracellular depletion of L-asparagine inhibits protein synthesis in lymphoblasts, inducing their apoptosis. Numerous studies have demonstrated that treatment with L-ASP improves survival of patients, but there are clear differences in the characteristics of the three currently available formulations. This article reviews the dosage, activity and side effects of the two L-ASP derived from Escherichia coli (native and pegylated), and the one derived from Erwinia chrysanthemi (Erwinia ASP). Despite its indisputable indication over the past50 years, there are still many points of contention, and its use is still marked by the side effects of the inhibition of protein synthesis. The short half-life of native forms, and the most frequently used parenteral administration by intramuscular injections, affects the quality of life of the patients. Therefore, recent studies claim to evaluate alternatives, such as the formulation of longer half-life pegylated L-ASP, and the use of intravenous formulations. There are encouraging results to date with both preparations. Still, further studies are needed to establish which should be the formulation and frontline indicated route of administration, optimal dosing, and management of adverse effects.