A Case of Exon 7 and 8 Deletion of Survival Motor Neuron Gene in Spinal Muscular Atrophy

Spinal muscular atrophy(SMA) is a genetic disorder of the motor neurons that cause muscular weakness and muscular atrophy due to anterior horn cell degeneration. Classic spinal muscular atrophy patient is caused by mutation in the chromosome 5(q11.2-q13.3), and the majority of the patient shows homozygous deletion of the telomeric survival motor neuron(SMN) gene in the chromosome 5. Deletion of exon 7 and 8 of the SMN gene and deletion of exon 4 and 5 of the neuronal apoptosis inhibitory protein(NAIP) are typically observed in SMA patients. The SMN protein plays a role in an essential cell metabolism process, the splicing of pre mRNA in the spliceosomes. We report a 7 month old male with SMA. He showed rapidly aggrdvatial muscular weakness and died at 7 months. His DNA analysis proved deletion of exon 7 and 8 of the telomeric copy of the SMN gene.

A Case of Type I Glycogen Storage Disease with Decreased Growth Hormone Secretion / 대한소아내분비학회지

Glycogen storage diseases(GSD) are inherited disorders affecting glycogen metabolism and type I GSD is due to the absence or deficiency of glucose-6-phosphatase(G6Pase) enzyme in the liver, kidney, and intestinal mucosa. The defect leads to inadequate hepatic conversion of G6P to glucose and thus make affected individuals susceptible to fasting hypoglycemia, and the accumulation of glycogen occurs in the liver and other organs. Type Ia is the most common form of GSD and clinically growth retardation may manifest of GSD itself rather than growth hormone deficiency(GHD), but we experienced a case of type I GSD with GHD in a 14-year-o1d male. The height was 125 cm, compatible with 50 th percentile of height of 8 years of age. He has doll-like face with fat cheek, relatively thin extremities, and metabolic acidosis, hyperuricemia, hypoglycemia, hyperlipidemia. GH stimulation test with clonidine and L-dopa revealed that the patient had decreased GH secretion. After laboratory work up including liver biopsy, he was diagnosed as type I GSD. Hypoglycemia was managed with frequent feeding with high starch diet(uncooked cornstarch). Metabolic acidosis and hyperuricemia were treated with sodium bicarbonate, allopurinol and probenecid. The patient is being followed at out-patient clinic with clinical improvement after of diet therapy and GH administration.