By Gary M. White, MD
X-linked reticulate pigmentary disorder (XLPDR) is a rare systemic disorder caused by a unique hypomorphic mutation in the POLA1 gene, which deregulates the type I IFN response. The first manifestations appear in the first months of life in the form of recurrent pneumonia, bronchiectasis, chronic diarrhea, and failure to thrive. A prominent manifestation is enterocolitis resembling inflammatory bowel disease.
With regard to the skin, a diffuse and reticulated skin hyperpigmentation is evident from childhood. Female carriers can be identified by the presence of linear hyperpigmentation following the lines of Blaschko.
Systemic manifestations can include recurrent respiratory tract infections, failure to thrive, corneal dystrophy with photophobia, hypohidrosis, severe diarrhea and colitis, hypospadias, and urethral stricture, dental anomalies (hypodontia, dental dysplasia), phimosis, syndactyly, hearing loss, gastroesophageal reflux, recurrent otitis, hepatosplenomegaly, and joint hypermobility. Many patients also have hypohidrosis and corneal inflammation leading to blindness.
Eur J Dermatol 2008;18:102–103.