NLRP12 autoinflammatory disease: a Chinese case series and literature review

As one of the systemic autoinflammatory diseases (SAIDs), the nucleotide-binding oligomerization domain-like receptor protein (NLRP)12 autoinflammatory disease (NLRP12-AD) is an autosomal dominant disorder associated with NLRP12 mutation. SAIDs have been hardly reported in the Chinese population, and NLRP12-AD has been reported only in Caucasians. We report the first case series of NLRP12-AD in the Chinese population coupled with literature review. Three Han Chinese adult patients with clinical phenotype suggestive of NLRP12-AD carrying NLRP12 variants were treated by the authors in 2015. Their phenotype and genotype were carefully studied. A PubMed search for SAIDs was conducted between January, 1990 and January, 2016, and we focused on NLRP12-AD. All three adult patients developed periodic disease in adulthood. They presented with recurrent fever (n = 3), polyarthralgia (n = 3), myalgia (n = 3), urticaria (n = 2), lymphadenopathy (n = 2), and erythema nodosa (n = 1). All patients carry the NLRP12 mutation F402L. Based upon our analysis of a total of 26 patients with NLRP12-AD in the literature, both familial and sporadic cases were equally reported and late-onset cases accounted for 28 %. NLRP12-AD patients typically present with periodic fever, urticaria-like rash, arthralgia/arthritis, myalgia, and lymphadenopathy. Genotyping identifies the NLRP12 gene mutations, notably F402L (55 %). Relative to the literature reports, our patients had the similar phenotypic and genotypic features. Patients with NLRP12-AD usually respond to glucocorticoid therapy. Our report is the first to confirm the presence of NLRP12-AD in the Chinese population. It highlights the importance of screening NLRP12 in patients with unexplained periodic fever syndrome.