Cryopyrin-associated periodic syndrome: an autoinflammatory disease manifested as neutrophilic urticarial dermatosis with additional perieccrine involvement.

A female newborn presented with a congenital urticarial rash that consisted of fluctuating well-demarcated pink or pale reddish macules or slightly raised papules and plaques. In addition, purulent cerebrospinal fluid was present in the absence of evidence of congenital infection. Skin biopsy revealed a sparse infiltrate throughout the entire dermis, including the eccrine adventitia. The infiltrate was composed mostly of neutrophils, but rarely lymphocytes and eosinophils could also be seen. No vasculitis was present. Because of the presenting attributes, a diagnosis of cryopyrin-associated periodic syndrome (CAPS) was considered and the neonatal-onset multisystem inflammatory disorder (NOMID) that represents the most severe expression of the CAPS clinical spectrum was favored. Diagnosis was confirmed by identification of a mutation in the cold-induced autoinflammatory syndrome-1 gene and by an observed response to treatment with the interleukin-1 receptor antagonist anakinra. Both the clinical and histopathological findings of the presented case may represent a distinct entity within the spectrum of aseptic neutrophilic dermatitis. We refer to this spectrum as neutrophilic urticarial dermatosis (NUD), which may serve as a cutaneous marker of autoinflammation. NUD with perieccrine involvement should prompt consideration of CAPS, especially NOMID, in the context of neonatal multisystem disease.

Abnormal cell surface antigen expression in individuals with variant CD45 splicing and histiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) and Langerhans cell histiocytosis (LCH) are members of a group of rare heterogenous disorders, the histiocytoses, characterized by uncontrolled accumulation of pleomorphic infiltrates of leukocytes. The etiology of these diseases is mainly unknown. CD45 is a hemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signaling in lymphocytes and different patterns of CD45 splicing are associated with distinct functions. Recently a polymorphism (C77G) in exon 4 of CD45 causing abnormal CD45 splicing and a point mutation affecting CD45 dimerization were implicated in multiple sclerosis in humans and lymphoproliferation and autoimmunity in mice respectively. Here we show that two patients with HLH exhibited abnormal CD45 splicing caused by the C77G variant allele, while a further 21 HLH patients have normal CD45. We have also examined 62 LCH patients and found three to have the C77G mutation. Peripheral blood thymus-derived (T) CD8(+) cells from normal individuals carrying the C77G mutation show a significant decrease in the proportion of cells expressing L-selectin and increased frequency of cells with LFA-1(hi) expression. It remains to be established whether C77G is a contributing factor in these histiocytic disorders.