Poikiloderma with Neutropenia, Clericuzio-Type Accompanied by Loss of Digits Due to Severe Osteomyelitis.

Poikiloderma with neutropenia (PN), Clericuzio-type is a rare autosomal recessively transmitted genodermatosis caused by biallelic mutations in the USB1 gene and is characterized by early-onset poikiloderma and chronic neutropenia. Nail dystrophy, palmoplantar hyperkeratosis, hypogonadotropic hypogonadism, and recurrent infections can be associated with the disease. Herein, we present a 27-year-old Turkish male patient newly diagnosed as PN, Clericuzio-type after confirmation of a c.531delA (p.His179MetfsX86) homozygous deleterious mutation in exon 5 of the USB1 gene. The presented case highlights the importance of genetic testing for avoiding misdiagnosis based solely on clinical findings, as well as the benefit of a multi-disciplinary diagnostic approach, as he was initially misdiagnosed as Rothmund-Thompson syndrome and subsequently diagnosed as PN, Clericuzio-type at age 27 years.