Polymorphism of UDP-glucuronosyltransferase Gene(UGT1A1) of Neonatal Hyperbilirubinemia in Korea / 소아과

PURPOSE: The incidence of neonatal hyperbilirubinemia is twice as high in East Asians as in whites and its metabolic basis has not been clearly explained. Recently, UDP-glucuronosyltransferase gene (UGT1A1) mutation was found to be a risk factor of neonatal hyperbilirubinemia in Japanese and Taiwanese Chinese. We studied whether neonatal hyperbilirubinemia is associated with mutation of UGT1A1, which is a key enzyme of bilirubin catabolism, in Korean. METHODS: The genomic DNA was isolated from 45 Korean full term neonates who had hyperbilirubinemia(serum bilirubin >12 mg/dL) with no obvious causes, and the 64 Korean neonates of the control population. We detected a missense mutation of Gly71Arg of UGT1A1 gene by using allele-specific polymerase chain reaction. Polymorphism was confirmed by direct sequencing. RESULTS: Two of the 45 neonates with serum bilirubin above 12 mg/dL had homozygous mutation and 16 neonates had heterozygous mutation. Two of the 31 neonates with serum bilirubin above 15 mg/dL had homozygous mutation and 13 neonates had heterozygous mutation. Thirteen of the control group had heterozygous mutation and homozygous mutation was not found. Allele frequency of Gly71Arg mutation in hyperbilirubinemia group was 0.22, which was significantly higher than 0.11 in the control group(P<0.0144). CONCLUSION: The missense mutation causing Gly71Arg of UGT1A1 was detected in the Korean neonatal hyperbilirubinemia. The high frequency of this missense mutation may be attributed to the high prevalence of hyperbilirubinemia in the Korean.

A Case of Recurrent Herpes Simplex Virus Disease of a Preterm Infant, Who Needed Continuous Oral Acyclovir Suppressive Therapy

Neonatal herpes simplex virus(HSV) infections result in significant morbidity and mortality. Although acyclovir treatment has improved survival, severe neurological sequelae can occur in the majority of survivors. HSV infections limited to the skin, eyes and mouth(SEM) can cause neurologic impairment. A direct correlation exists between the development of neurologic deficits and the frequency of cutaneous HSV recurrences. National Institutes of Allergy and Infectious Diseases(NIAID) Collaborative Antiviral Study Group conducted a phase I/II trial of continuous oral acyclovir therapy for the suppression of cutaneous recurrences. We describe a preterm infant who had two recurrences after neonatal SEM disease had been treated with intravenous acyclovir, and there were no more recurrences after continuous oral acyclovir suppressive therapy for six months. We report this case with a review of related literature.

Pulmonary Embolism In Childhood Minimal Change Nephrotic Syndrome

PURPOSE:We investigated the incidence and predisposing factors of pulmonary embolism in minimal change nephrotic syndrome(MCNS). METHODS:Lung perfusion scan using 99mTC-MAA were done on 14 patients who were diagnosed to minimal change nephrotic syndrome. Group A; Five patients who had perfusion defects on scan, Group B; Nine patients who had no perfusion defect on scan. Between the two groups, the differences of platelet number, hematocrits, albumin, cholesterol, triglyceride, proteinuria were evaluated. RESULTS:Five patients were found to have perfusion defect consistent with pulmonary embolism(35.7%). However, there were minimal or no respiratory symptoms and signs. In our laboratory studies, the mean proteinuria on admissions was 676+/-31 mg/m2/hr in the group with pulmonary embolism, and 313+/-28 mg/m2/hr in the group without pulmonary embolism. There were more severe proteinuria in group with pulmonary embolism(P<0.05). The mean platelet count at early stage of remission after steroid treatment was 746,600+/-280,000/mm3 in the group with pulmonary embolism, 511,890+/-90,000/mm3 in the group without pulmonary embolism. There were significant difference of platelet count between the two groups(P<0.01). In patients with pulmonary embolism, there were more higher and sustained increasement of platelet count. All cases of pulmonary embolism were treated with dipyridamole(5 mg/kg). In 4 cases the perfusion defects were improved in two weeks, however, one case showed persistent perfusion defect after 1 month. CONCLUSION:Our study suggested that pulmonry embolism might be one of the major complications in childhood MCNS. The occurrence rate was correlated with severity of proteinuria before treatment and sustained increasement of platelet counts in early remission state after steroid treatment. Therefore, the scintigraphic pulmonary perfusion study is mandatory in childhood MCNS, especially in the high risk patients, such as the patients with severe proteinuria and sustained increasement of platelet count.

A Case of Cerebral Infarction Associated with Mycoplasma pneumoniae Infection

Mycoplasma pneumoniae has been shown to be of etiologic importance in cases of upper-and lower-respiratory tract infections, especially in children and young adults. It may cause a variety of extrapulmonary manifestations in multiple organ systems, most commonly the central nervous system. The extrapulmonary syndromes include meningitis, cerebral infarction, acute transverse myelitis, psychosis, cerebellar ataxia, Guillain-Barr syndrome and Reye syndrome. Cerebral infarction as a complication of mycoplasma infection in children has been rarely reported. We report the first documented case in Korea of cerebral infarction preceded by M. pneumoniae pneumonia in a 7-year-old boy, with a brief review of literatures.