Granulomas in common variable immunodeficiency: a diagnostic dilemma.

A 60-year-old man with common variable immunodeficiency presented with a 7-year history of violaceous plaques and papules on the thighs, arms and trunk. In the preceding 2 years he had developed new lesions on both hands. He had been previously diagnosed with sarcoidosis on the basis of skin and visceral histology, but subsequent opinion was that these were sarcoid-like granulomas rather than being representative of true sarcoidosis. Biopsy of the hand lesions showed necrotizing granulomas, and a single acid-fast bacillus (AFB) was identified on Wade-Fite stain. Subsequent repeat tissue biopsies for histology, culture and polymerase chain reaction testing failed to confirm the presence of mycobacterial organisms and it was felt that the organism was a contaminant introduced during tissue processing. The hand lesions responded well to intralesional injections of triamcinolone acetonide 10 mg/mL and oral tetracycline 500 mg b.d. was later introduced with a good clinical response. The diagnostic dilemma of finding granulomatous inflammation in a patient with common variable immunodeficiency, and the significance of a single AFB on histology are discussed. The treatment of sarcoid-like granulomas with tetracycline therapy is also commented on.