Incontinentia Pigmenti: Late Sequelae and Genotypic Diagnosis: A Three‐Generation Study of Four Patients

Abstract

Late cutaneous signs of incontinentia pigmenti (IP) are often subtle and 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 the women in her family revealed that her mother, her maternal aunt, and her grandmother had subtle skin signs reminiscent of IP. The four family members proved to be informative for DNA markers in the Xq28 region. Familial cases of IP are sometimes missed due to the lack of recognition of some late skin signs that are not always hyperpigmented streaks. Subtle, faint, hypochromic or atrophic lesions in a linear pattern may occur. Thus an accurate diagnosis of the women in a particular family also requires anamnestic data and recognition of extracutaneous anomalies. When a clinical diagnosis has been made, DNA marker analysis allows us to offer a prenatal diagnosis with minimal risk of error in case of further pregnancy. However, early testing of chorionic villus samples does not allow one to predict the severity of the disease in an affected fetus.

Clinical study of 20 patients with incontinentia pigmenti

“…13 These lesions have been recognized in the literature as likely to represent a late, and often clinically subtle, sole remaining cutaneous feature of IP in adults. 14,15 Our study did not support the claim that alopecia is more common in adults. The high incidence of this finding in children may reflect the fact that this skin anomaly was specifically sought on physical examination; we also considered mild cases of alopecia.…”

Incontinentia pigmenti case series: clinical spectrum of incontinentia pigmenti in 53 female patients and their relatives

“…Stage IV pale hairless anhidrotic streaks on the calves were present in 92% of our series. These lesions have been recognized in the literature 14,15 as probably a late, and often clinically subtle, sole remaining cutaneous feature of IP in adults 24,25 . Our experience is that they are a very reliable marker of IP in adult women, as all 22 of our older cohort of relatives with IP had these stage IV lesions.…”

Incontinentia pigmenti

“…However, due to the subtlety of atrophic lesions, it appears that this phase may have been underreported in the past and therefore may occur in most patients with IP. 16-18 …”