PReS-FINAL-2196: The clinical significance of the Q703K mutation of NLRP3 gene. A multicentric national study

Results The Q703K mutation was found in the 35 screened patients (pediatric 17 vs adult 18, with the mean age was 23,7 years, range 3-64). The mean age at onset was 21,5 years (range 0,5-57). Thirty patients were heterozygous for theQ703K mutation only. Two pts displayed other mutations of NLRP3 gene (M604I in one CINCA and D303N and V198M in a MWS). Three patients display a monoallelic variant of MEFV gene (R202Q, V726A, D303N). The mean follow-up was 2,5 years (range 0,2-8). The prevalent clinical features were fever and urticarial rash (23 pts), urticarial rash without fever (6 pts) and periodic fever only (6 pts). The main clinical manifestations and treatment are reported in the table. According to the judgment of the physician in charge, a CAPS-like phenotype was observed in 23 patients (66%). In 12 pts (34%) an alternative diagnosis was pointed out (mainly undifferentiated periodic fever). The frequency of the variant Q703K in normal controls was 2,22%.