Abstract

Yao syndrome (YAOS), formerly named NOD2-associated autoinflammatory disease, is a polygenic autoinflammatory condition requiring genetic testing for diagnosis. In addition to the most common clinical features consisting of episodic fever, arthritis, GI symptoms, ankle edema, and eyelid erythema/swelling, a wide spectrum of rashes have been reported (Yao 2011). Likewise in the reported literature, biopsies of rashes associated with YAOS have revealed an array of histopathological patterns: spongiotic, perivascular, granulomatous, and pigmented pruritic dermatosis (Yao 2013). In our case series of 5 patients with YAOS, both female and male ranging from 30 to 75 years old, we further demonstrate the heterogeneity of histopathology findings among this patient population. Our study shows patients with superficial perivascular dermatitis (with and without mast cells); leukocytoclastic vasculitis; spongiotic dermatitis; and interface lichenoid dermatitis. These correspond with clinical presentations of urticaria; Gottron’s-appearing papule; pruritic palpable purpuric eruption of bilateral lower extremities; burning eruption of the lower trunk and extremities; and pruritic reticulated eruption of the arms and trunk. We further conclude that there is heterogeneity in cutaneous manifestations of YAOS, with corresponding lack of consensus for characteristic histopathological features. We highlight the importance of referral to rheumatology and prioritizing genetic testing in patients with other symptoms of YAOS to prevent a delay in diagnosis by treating non-specific cutaneous manifestations alone.