INCONTINENTIA-PIGMENTI - LATE SEQUELAE AND GENOTYPIC DIAGNOSIS - A 3-GENERATION STUDY OF 4 PATIENTS

Late cutaneous signs of incontinentia pigmenti (IP) are often subtle a nd misdiagnosed. We focus on these somewhat confusing clinical markers in a family, and on the genotypic diagnosis based on DNA analysis. An infant was born with a typical IP rash, Dermatologic examination of t he women in her family revealed that her mother, her maternal aunt, an d her grandmother had subtle skin signs reminiscent of IP. The four fa mily members proved to be informative for DNA markers in the Xq28 regi on. Familial cases of IP are sometimes missed due to the lack of recog nition of some late skin signs that are not always hyperpigmented stre aks. Subtle, faint, hypochromic or atrophic lesions in a linear patter n may occur. Thus an accurate diagnosis of the women in a particular f amily also requires anamnestic data and recognition of extracutaneous anomalies. When a clinical diagnosis has been made, DNA marker analysi s allows us to offer a prenatal diagnosis with minimal risk of error i n case of further pregnancy. However, early testing of chorionic villu s samples does not allow one to predict the severity of the disease in an affected fetus.