Skin signs of primary immunodeficiencies: how to find the genes to check.

Primary immunodeficiencies (PIDs) are a heterogeneous group of rare diseases that result from defects in immune system development and/or function. The clinical manifestations of PIDs are highly variable, but most disorders involve at least an increased susceptibility to infection. Furthermore, cutaneous manifestations are very common in PIDs. As an easily accessible organ, the skin can be crucial for early diagnosis and treatment. This is relevant for preventing significant disease-associated morbidity and mortality. We provide a table that enables the reader to find the possible diseases and corresponding gene defects based on the skin manifestations of the suspected PIDs. To our knowledge, this is the first review that allows the reader to find relevant PIDs and the respective gene defects through solitary or combined skin signs.

Neurocutaneous melanosis in association with Dandy-Walker malformation: case report and literature review.

Neurocutaneous melanosis (NCM) is a rare congenital noninheritable phacomatosis characterized by large and/or numerous cutaneous congenital melanocytic naevi (CMN) in combination with melanocytic leptomeningeal tumours. Dandy-Walker malformation (DWM) consists of a cystic dilatation of the fourth ventricle communicating with the posterior fossa, and a high insertion of the tentorium and hypoplasia/aplasia of the cerebellar vermis (partially caused by Zic1(+/-)Zic 4(+/-) on 3q2). An association of NCM and DWM is very rare, with only 15 previously reported cases to our knowledge. We present an 8-year-old girl with multiple CMN and DWM. A ventriculoperitoneal shunt operation was performed when she was 1 day old. Her neurological symptoms to date comprise headaches, nausea and vomiting as a result of ventriculoperitoneal shunt dislocation at the age of 4 years. The diagnosis is provisional asymptomatic multiple CMN-type NCM in association with DWM.