Diabetes mellitus por mutación en el gen de glucokinasa: caso clínico / Diabetes mellitus caused by a mutation of glucokinase gene: report of an affected family

Maturity-Onset Diabetes of the Young (MODY) refers to a heterogeneous group of monogenic diabetes. Unlike other types of MODY characterized by genetic defects in transcription factors, MODY 2 is triggered by metabolic alterations caused by mutations of glucokinase (GCK), the first enzyme of the glycolytic pathway. We report a three-generation Chilean family with multiple cases affected with this disease. The index case is a patient who presented severe neonatal hyperglycemia (831 mg/dl, without ketosis) requiring continuous infusion of insulin, which was suspended after 48 hours with normalization of blood glucose. Subsequently, continuous glucose monitoring at 4 months of age revealed 47% of tissue glucose levels above 140 mg/dl, with fasting glucose levels between 120 and 166 mg/dl. The genetic analysis revealed a previously reported mutation in heterozygous state of the GCK gene (c.148C>T; p.His50Tyr). This mutation was also identified in more than one affected relative in the last two generations, with a transmission pattern suggestive of dominant inheritance. GCK gene sequencing led to a correct molecular diagnosis of MODY 2 while bioinformatic analysis indicated the possible molecular causes of the enzyme dysfunction. The knowledge of the molecular diagnosis allowed an adequate medical treatment for this disease.

Modalidades de imagen en la evaluación de enfermedad inflamatoria intestinal / Imaging techniques in the evaluation of inflammatory bowel disease

La enfermedad inflamatoria intestinal es una patología crónica, con una incidencia cada vez mayor. Dentro de este grupo de afecciones, la enfermedad de Crohn y la colitis ulcerosa son las más frecuentes. La enterografía por tomografía computada (ETC) y por resonancia magnética (ERM) son las modalidades de elección para la evaluación y seguimiento de la entidad, permitiendo examinar la apariencia de la mucosa, la pared intestinal, las manifestaciones extraintestinales y las complicaciones asociadas. La elección del estudio debe hacerse de acuerdo con la condición clínica de cada paciente

Inflammatory bowel disease is a chronic condition with increasing incidence. Crohn's disease and ulcerative colitis are the most common pathologies. Computed tomography (CT) enterography and magnetic resonance (MR) enterography are the methods of choice for evaluating and monitoring this entity, assessing the appearance of intestinal wall, mucosa, extra-intestinal manifestations, and associated complications. The preferred imaging methods must be selected according to the clinical conditions of the patient

Inducción de la pubertad en el síndrome de Turner / Induction of puberty in Turner's syndrome

Turner's Syndrome is the most frequent cause of female hypogonadism. Puberty must be pharmacologically induced in over 80 percent of these girls. Induction must be completed in a manner closest to physiology as possible. It is recommended that this induction be initiated at age 12 y.o. with natural estrogens (17 beta estradiol) in low dosage, equivalent to 1/10 a 1/8 of substitution dose, increasing stepwise and adding, after two years, a progestin to generate a menstruation. This revision shows various proposed schemes, as well as therapeutic alternatives available in Chile.

El síndrome de Turner es la causa más frecuente de hipogonadismo femenino. La pubertad tiene que ser inducida farmacológicamente en más del 80 por ciento de estas niñas. Esta inducción debe hacerse de la forma más fisiológica posible. Se recomienda iniciar esta inducción a los 12 años de edad cronológica, con estrógenos naturales (17 beta estradiol) en dosis bajas, equivalentes a 1/10 a 1/8 de la dosis de sustitución, aumentando la dosis por peldaños y agregando luego de dos años una progestina cíclica para generar una menstruación. En esta revisión se muestran los diversos esquemas propuestos en la literatura así como las alternativas terapéuticas existentes en Chile.

Hiperplasia suprarrenal no clásica, características clínicas y genéticas / Clinical and genetic features of non classical adrenal hyperplasia

Background: The non classical form of congenital adrenal hyperplasia (NCAH) is increasingly recognized inhyperandrogenic patients, with variable phenotypic expression. Aim: To determine the clinical, hormonal, andgenetic characteristics of a group of patients with NCAH. Patients and methods: The medical records of 57NCAH patients were retrospectively reviewed. The diagnosis was established by basal or post-ACTH-stimulation 17-hydroxyprogesterone (17-OHP) levels >7 ng/mL and > 15 ng/mL, respectively. Patients with post-ACTH 17-OHP levels between 10-15 ng/mL, and with one identified allele o without genetic tests, were consideredas heterozygous. Genotyping for 10 mutations was performed by PCR. Results: The average age of diagnosis was 12.4 +/- 0.9 years. Six patients were male. Pubarche and hirsutism were the clinical signs more frequently described in patients below 10 years of age (25/29) and over 10 years of age (11/24), respectively. A basal 17-OHP > 7 ng/mL was observed in 36 patients; the post ACTH 17-OHP was between 10-15 and > 15 ng/mL in 5 and 17 patients, respectively. Genotype analyses were performed in 38 patients. V281L was carried on approximately 68.4 percent of all alleles and 29 percent of patients carried severe mutations. Only one of five possible carrier patients, was diagnosed as NCAH after the genetic test (V281L/ In2splice). Conclusions: Males with NCAH were apparently sub-diagnosed. Pubarche and hirsutism were the more frequently reported signs. The genetic test is complementary in the diagnosis of NCAH. One third of the patients carried a classic mutation and could have an increased risk to have siblings with Classical CAH.

Neutropenia inducida por propiltiouracilo en paciente con síndrome de Down e hipertiroidismo / Neutropenia induced by propylthiouracil in patient with down syndrome and hyperthyroidism

Se presenta el caso de un paciente de sexo masculino de 10 años de edad, con antecedente de síndrome de Down, que consulta por cuadro de hipertiroidismo compatible con enfermedad de Base-dow-Graves. Recibe tratamiento con propiltiouracilo en dosis de 5 mg/kg/día. Veinte días después de iniciado el tratamiento, desarrolla agranulocitosis secundaria al uso de PTU. Se realiza una revisión sobre el hipertiroidismo en pacientes con síndrome de Down, el tratamiento de esta patología, y las reacciones adversas más frecuentes descritas en relación al uso de PTU.