Eczema the hidden face of primary immunodeficiency diseases

Primary immunodeficiency diseases (PIDs) are a group of more than 130 disorders caused by genetic defects of the immune system. Most of these disorders are caused by single gene defects, but the variable penetrance of these mutations results in heterogeneous phenotypes which lead to a delay in the diagnosis. In the USA, the prevalence of all PIDs per 100,000 has increased over the last decade from 66.6 in 2003 to 126.8 in 2012 and this could reflect the rise in the disease awareness. The classical clinical presentation of PIDs includes recurrent or unusual infections, however, new presentations are now coming to attention such as autoimmune diseases, malignancy and cutaneous manifestations. Cutaneous manifestation in PIDs affects around 40 % to 70 % of patients and they include various presentation as eczema, cutaneous granulomas, recurrent abscesses, dysplasia of skin, hair, and nails, autoimmune conditions, and others. Dhouib et al found that the incidence of cutaneous manifestation among 200 children with PIDs to be 56%, whereas Al-Herz et al and Moin et al found it to be 48% and 32% respectively. Cutaneous manifestations could be the first presenting symptoms and faulty presenting to dermatologist. In a series of 75 patients with severe dermatitis with no known underlying primary immunodeficiency, Aghamohammadi et al identified 5 patients with hyperimmunoglobulin E syndrome (HIES) and one patient with Wiskott Aldreich syndrome (WAS). This raises the awareness to suspect an underlying PID in patients presenting with severe and nonresolving cutaneous manifestation. Eczema (Atopic dermatitis “AD”) is an inflammatory, chronically relapsing, noncontagious and extremely pruritic skin disease. It is commonly associated with an elevation in total immunoglobulin E, which sometimes correlates with disease severity. The prevalence of childhood AD ranges from 15% to 30%. AD is one of the commonest cutaneous manifestations for some PID diseases and sometime used as one of the disease diagnostic critieria of HIES, WAS, and others (Table). It is characterized by being severe, resistant to treatment and associated by chronic or recurrent viral or bacterial infections. Such condition confirms the importance of eliciting history of recurrent infections in affected patients or history of infection in any of their family members .