Pulmonary cystic disease in ankylosing spondylitis: two cases with unusual superinfection.

Two ankylosing spondylitis patients with upper lobe fibrocystic disease are reported. The occurrence of pulmonary parenchymal disease as part of the primary pathologic process in ankylosing spondylitis is now accepted as an integral part of the disease. The frequency of superinfection of cavitary lung disease with Aspergillus is noted. Another unusual superinfection, Mycobacterium scrofulaceum, is reported.