Urticaria-angioedema paraneoplastic syndrome associated with renal cell carcinoma

Urticaria and angioedema are part of a benign syndrome in the majority of cases. However, they can occur as paraneoplastic syndromes. A 46 year old woman was observed with urticaria, angioedema and progressive fatigue and adynamia of unknown cause. The urticaria responded to anti -histamines, but the angioedema did not and had a circadian evolution. The urticaria was mild, but the angioedema caused severe episodes. Blood tests revealed normal red and white blood cell counts as, normal renal, liver and thyroid function. Sedimentation rate, complement serum proteins (C1, C3, C4 and C1q) and C1 -esterase inhibitor concentrations were within normal ranges. A CT -scan demonstrated a 4.8 cm diameter cyst in the right kidney, deemed as a probable renal cells carcinoma on a posterior Uro -CT-scan. A radical nefro -ureterectomy was successfully performed and tumor histology established a cromophobe renal cells carcinoma (RCC) diagnosis at a pTNM pT1b Nx R0. A few days after surgery, a fast improvement of facial angioedema was observed and one month later its complete disappearance was ascertained, without any recurrence during a subsequent one -year follow -up. The evaluation of patients with urticaria and angioedema does not usually require a lot of complementary tests. However, further study should be considered when these symptoms are present with atypical characteristics.