A non-cardiac cause of bilateral leg swelling

A 65 year old man described swelling in both legs, which had worsened over six weeks. He also reported vague abdominal discomfort and tiredness. Examination of the lower limbs revealed pitting oedema bilaterally up to the groin, but no erythema, tenderness, or warmth. The patient was otherwise systemically well with normal heart sounds and a clear chest examination. There were no palpable masses in the abdomen or lymphadenopathy. Blood tests were unremarkable other than a normocytic anaemia (haemoglobin 95 g/L; normal range 130-180), C reactive protein of 33.0 mg/L (normal range 0-5.0) and a raised IgG4 level (3.55 g/L; normal range 0.08-1.4). No deep vein thrombosis was found on Doppler ultrasound. The patient had computed tomography of his abdomen and pelvis, which showed retroperitoneal fibrosis (fig 1). A unifying diagnosis was made of retroperitoneal fibrosis secondary to IgG4 related disease.