SJOGREN-LARSSON SYNDROME - TECHNIQUE AND TIMING OF PRENATAL-DIAGNOSIS

Background: Sjogren-Larsson syndrome is an autosomal recessive disease with sequelae including ichthyosis, mental retardation, and spasticit y. Although fetal skin biopsy has permitted prenatal diagnosis of Sjog ren-Larsson syndrome in the late second trimester, it is accompanied b y substantial risks, including fetal loss, premature labor, and detect ion at a gestational age close to the legal limit for pregnancy termin ation in most states. A new technique involving biochemical assay of c ultured amniocytes for reduced levels of fatty alcohol:oxidized nicoti namide-adenine dinucleotide (NAD+)-oxidoreductase may allow earlier an d less invasive detection of Sjogren-Larsson syndrome. Case: A 38-year -old Lebanese woman, gravida 6, para 3, presented for prenatal diagnos is of Sjogren-Larsson syndrome following a history of two children bor n with the disease. At 19 weeks' gestation, multiple fetal skin biopsi es were obtained by ultrasound-guided transabdominal percutaneous inse rtion of biopsy forceps. Histologic examination of the specimen reveal ed no evidence of Sjogren-Larsson syndrome. However, assay of fatty al cohol:NAD+-oxidoreductase in cultured amniocytes obtained at fetal ski n biopsy showed a profound enzymatic deficiency. Additional fetal skin biopsies were obtained at 23.5 weeks' gestation, and histologic exami nation was positive for Sjogren-Larsson syndrome. The patient elected to terminate the pregnancy, and a subsequent autopsy on the fetus conf irmed Sjogren-Larsson syndrome. Conclusion: This case demonstrates the limitations of histologic examination of fetal skin specimens for the diagnosis of Sjogren-Larsson syndrome and indicates the potential val ue of biochemical detection from fetal amniocytes. This new technique may allow earlier diagnosis of Sjogren-Larsson syndrome, is less invas ive, and may be less psychologically traumatic for the patient if she elects to terminate the pregnancy.