Genetic predisposition to two rheumatic diseases.

The co-existence of ankylosing spondylitis and rheumatoid arthritis is uncommon and usually occurs in a male with a long history of back pain followed by the appearance of clinical features of ankylosing spondylitis, while features of rheumatoid arthritis develop in the third or fourth decade of life. Recently, histocompatibility (HLA) antigens have partially elucidated the genetic factors predisposing to both diseases. We report a patient with ankylosing spondylitis and rheumatoid arthritis who had the associated HLA genes.

Human pulmonary dirofilariasis.

Dirofilaria immitis, the canine heartworm, is a relatively rare, but well-documented cause of human lung disease. The disease presents in man as a solitary, peripheral parenchymal lung nodule which may simulate a peripheral lung neoplasm. This case is the first report of the disease in New Zealand, a country where the parasite has not become established in the dog population. A brief review of the life cycle, epidemiology and clinical data relating to human dirofilariasis is included.