Spectrum of pathogenic mutations and associated polymorphisms in a cohort of 44 unrelated patients with long QT syndrome.

Long QT syndrome (LQTS) is a rare and clinically heterogeneous inherited disorder characterized by a long QT interval on the electrocardiogram, increased risk of syncope and sudden death caused by arrhythmias. This syndrome is mostly caused by mutations in genes encoding various cardiac ion channels. The clinical heterogeneity is usually attributed to variable penetrance. One of the reasons for this variability in expression could be the coexistence of common single nucleotide polymorphisms (SNPs) on LQTS-causing genes and/or unknown genes. Some synonymous and nonsynonymous exonic SNPs identified in LQTS-causing genes may have an effect on the cardiac repolarization process and modulate the clinical expression of a latent LQTS pathogenic mutation. We report the molecular pattern of 44 unrelated patients with LQTS using denaturing high-performance liquid chromatography analysis of the KCNQ1, KCNH2, SCN5A, KCNE1 and KCNE2 genes. Forty-five disease-causing mutations (including 24 novel ones) were identified in this cohort. Most of our patients (84%) showed complex molecular pattern with one mutation (and even two for four patients) associated with several SNPs located in several LQTS genes.

[Arteriovenous malformations of the vein of Galen]. / Malformación arteriovenosa de la vena de Galeno.

Vein of Galen arteriovenous malformations encompass a diverse group of vascular anomalies that share a common feature: dilatation of the vein of Galen. Although clinical presentations are highly variable, depending on age of presentation, signs and symptoms overlap between age groups. The association of heart failure and cranial bruit constitutes the most striking clinical presentation in neonates. However, less severe and fulminant modes of presentation are frequent in older infants, children, and adults. Treatment approaches consist of symptomatic treatment of heart failure on the one hand and of surgery or endovascular treatment on the other. The results of the latter have improved in recent years, opening up a broad spectrum of new possibilities. We present the case of an asymptomatic 15-day-old neonate who presented an arteriovenous malformation of the vein of Galen and who was treated with endovascular occlusion of the arterial afferents. An excellent result was obtained with no evidence of neurological abnormalities.

[Diagnostic test in emergency departments for bacterial infections in infants younger than 12 months]. / Orientación diagnóstica en la unidad de urgencias en lactantes menores de 12 meses con infección bacteriana.

OBJECTIVE: To evaluate clinical and analytic numeric data that may help the emergency departments to identify bacterial infections in infants. PATIENTS AND METHODS: A retrospective study of 430 infants with bacterial growth in cultures (culture from blood, 30; urine, 207; stools, 193, and/or cerebrospinal fluid, n 25) was performed. These patients were compared with a control group (n 430), randomly selected from patients aged less than 12 months with negative cultures who were hospitalized with suspected infection. Neonates and surgical patients were excluded from both groups. Statistical analysis was performed using Student's t-test for independent samples, Levene's test for the study of equality of variances, bivariate correlation and one-factor ANOVA, and receiver-operating characteristic (ROC) curves and odds ratios were calculated when statistically significant (p < 0.05) results were obtained. These analyses were performed using the SPSS 10.0 statistical software package. RESULTS: Of the infants admitted to the pediatric unit, 11.7 % had at least one positive bacterial culture. Temperature (p 0.005), leucocyte count (p 0.003), percentage of neutrophils (p < 0.0001) and C-reactive protein (p < 0.0001) were significantly higher in infants with positive cultures. In invasive infections significant differences were found in sex (more frequent in males) (p 0.03), heart rate (p < 0.0001) and respiratory rate (p 0.003). In the ROC curves, the best diagnostic yield was obtained for C-reactive protein (0.93 for a cutoff value of 29 mg/l, 86 % specificity and 91 % sensitivity). CONCLUSION: C-reactive protein is essential for diagnosis of bacterial infection in infants in the emergency department.

[Ruptured aneurysm of the sinus of Valsalva in a boy with ventricular septal defect]. / Rotura de aneurisma del seno de Valsalva en un niño con comunicación interventricular.

Aneurysmal dilatation of the sinus of Valsalva is a rare structural cardiac abnormality in children. It appears to be more common in Asia. It may be clinically silent for many years but these defects frequently coexist with other cardiac malformations, causing, when rupture occurs, unexpected symptoms that are not explained by the original defects. We report a case of ruptured aneurysm of the sinus of Valsalva in a 12-year-old boy diagnosed with ventricular septal defect in the neonatal period with an uneventful course. The boy suddenly developed acute prechordal pain, symptoms of low heart output and systolic-diastolic murmur. The diagnosis of ruptured aneurysm of the sinus of Valsalva was based on echocardiography. Surgical treatment was required to close the ventricular septal defect and repair the aorta, without valvular replacement. The postoperative course was uneventful. We conclude that is extremely important to have a degree high suspicion of this entity in previously asymptomatic children, with or without cardiac anomalies, who suddenly present this kind of heart failure and abrupt changes in cardiac auscultation.

[Neonatal cholestasis associated with liver failure as a clinical manifestation of cystic fibrosis]. / Colestasis del lactante con fallo hepático asociado como forma de presentación de la fibrosis quística.

Cystic Fibrosis is the most frequent hereditary disease in Caucasians. Its clinical presentation may be very variable. Neonatal cholestasis is a typical but rare primary clinical manifestation that usually occurs in the first 3 weeks of life. It is often associated with meconium ileus. We present the case of an infant with cystic fibrosis whose primary clinical manifestation was cholestasis and liver failure at the age of 6 weeks.