Reconstrucción microquirúrgica de cabeza y cuello en paciente pediátrico / Micro-surgical reconstruction of the head and neck in a pediatric patient

OBJETIVO: Realizar un análisis retrospectivo de pacientes pediátricos sometidos a reconstrucciones con injertos libres microvasculares del territorio maxilofacial en el Hospital Luis Calvo Mackenna entre los años 2014 y 2018. MATERIALES Y MÉTODO: Se realizó un análisis de los casos reconstruidos entre los años indicados. RESULTADOS: Un total de 11 pacientes fueron incluidos en la muestra, 7 hombres y 4 mujeres. El rango de edad de los pacientes fue entre 3 a 17 años (media 10,1). Siete colgajos de fíbula, 3 dorsales y 1 anterolateral de muslo fueron utilizados para reconstrucción. La tasa de éxito de los colgajos fue de un 100%. Discusión: Se realizó una discusión de los colgajos y sus principales indicaciones en pediatría y se compararon los resultados de la revisión con los casos reportados. CONCLUSIÓN: El estudio preoperatorio, una adecuada planificación, la rehabilitación de la oclusión dentaria, la reconstrucción simétrica y mantener el contorno facial deben ser objetivos de la reconstrucción.

AIM: Carry out a retrospective analysis of pediatric patients undergoing reconstructions with free micro-vascular grafts of the maxillofacial territory at the Luis Calvo Mackenna Hospital during the years 2014 and 2018. MATERIALS AND METHOD: Retrospective analysis of the cases reconstructed during the years 2014 and 2018 was made. RESULTS: A total of 11 patients were included in the sample, 7 men and 4 women. The age range of the patients was between 3 to 17 years (mean 10.1 years) . Seven Fibula flaps, 3 dorsal and 1 anterolateral thigh flaps were used for reconstruction. The success rate of the flaps was 100%. DISCUSSION: A discussion of the flaps and their main indications in pediatrics was made and the results of the review were compared with the cases reported. CONCLUSION: The pre-operative study, adequate planning, the rehabilitation of the dental occlusion, the symmetry reconstruction and maintaining the facial contour must be objective of the reconstruction.

Characterization of Phenyalanine Hydroxylase Gene Mutations in Chilean PKU Patients.

Phenylketonuria (PKU, OMIM 261600) is an autosomal recessive disease, caused by mutations in the Phenylalanine Hydroxylase (PAH) gene situated in chromosome 12q22-q24.2. This gene has 13 exons. To date, 991 mutations have been described. The genotype is one of the main factors that determine the phenotype of this disease. OBJECTIVE: Characterize PKU genotype and phenotype seen in Chilean PKU patients. METHODS: We studied the PAH gene by restriction fragment length polymorphism (RFLP) and/or sequencing techniques to identify pathogenic mutations in 71 PKU subjects. We classified the phenotype according to Guldberg predicted value. RESULTS: We identified 26 different mutations in 134 of the 142 alleles studied (94.4%), 88.7% of the subjects had biallelic pathogenic mutations while 11.3% had only one pathogenic mutation identified. Compound heterozygous represented 85.9% of the cases. Exon 7 included the majority of mutations (26.9%) and 50% of mutations were missense. The most frequent mutations were c.1066-11G > A, c.442-?_509+?del and p.Val388Met. The majority of subjects (52.3%) had the classic phenotype. CONCLUSIONS: The most frequent mutations in our Chilean PKU population were p.Val388Met, c.442?_509+?del and c.1066-11G > A. It is possible to predict phenotype by detecting the genotype, and use this information to determine disease prognosis and adjust patient's medical and nutritional management accordingly.