MedGen

An inherited epidermal disorder with characteristics of palmoplantar keratoderma, linear hyperkeratotic papules on the flexural side of large joints (cord-like distribution around wrists, in antecubital and popliteal folds), hyperkeratotic plaques (on neck, axillae, elbows, wrists, and knees), mild ichthyosiform scaling, and sclerotic constrictions around fingers that present flexural deformities. The disease is caused by homozygous mutation in the POMP gene. [from SNOMEDCT_US]

Proteasome-associated autoinflammatory syndrome-2 (PRAAS2) is an autosomal dominant disorder with onset in early infancy. Affected individuals develop severe inflammatory neutrophilic dermatitis, autoimmunity, and variable immunodeficiency (summary by Poli et al., 2018). For a discussion of genetic heterogeneity of PRAAS, see PRAAS1 (256040). [from OMIM]

This autosomal recessive systemic autoinflammatory disorder is characterized by early childhood onset of annular erythematous plaques on the face and extremities with subsequent development of partial lipodystrophy and laboratory evidence of immune dysregulation. More variable features include recurrent fever, severe joint contractures, muscle weakness and atrophy, hepatosplenomegaly, basal ganglia calcifications, and microcytic anemia (summary by Agarwal et al., 2010; Kitamura et al., 2011; Arima et al., 2011). This disorder encompasses Nakajo-Nishimura syndrome (NKJO); joint contractures, muscular atrophy, microcytic anemia, and panniculitis-induced lipodystrophy (JMP syndrome); and chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome (CANDLE). Among Japanese patients, this disorder is best described as Nakajo-Nishimura syndrome, since both Nakajo (1939) and Nishimura et al. (1950) contributed to the original phenotypic descriptions. Genetic Heterogeneity of Proteasome-Associated Autoinflammatory Syndrome See also PRAAS2 (618048), caused by mutation in the POMP gene (613386) on chromosome 13q12; PRAAS3 (617591), caused by mutation in the PSMB4 gene (602177) on chromosome 1q21; PRAAS4 (619183), caused by mutation in the PSMG2 gene (609702) on chromosome 18p11; and PRAAS5 (619175), caused by mutation in the PSMB10 gene (176847) on chromosome 16q22. [from OMIM]