Whipple's disease, familial Mediterranean fever, adult-onset Still's disease, and enteropathic arthritis.
Whipple's disease is a rare multisystem disorder of infectious etiology. Efforts to culture the responsible organism have been unsuccessful. Nucleotide sequencing and amplification of bacterial 16S ribosomal DNA revealed the organism to be most similar to bacteria of the Rhodococcus, Streptomyces, and Arthrobacter genera. Several clinical studies of the long-term use of colchicine for the treatment of familial Mediterranean fever demonstrate its utility for symptom control and prevention of complications by amyloidosis in both adults and children. Normal growth, development, and subsequent fertility were seen in children treated with colchicine. Adult-onset Still's disease has previously been thought to have a generally good outcome, although some patients develop chronic arthritis and disability. No markers have been available for prognosis. A study of 62 patients revealed the presence of polyarthritis, root joint involvement, and rash at initial presentation to be associated with a poorer outcome. Enteropathic arthritis may be seen as a complication of both Crohn's disease and ulcerative colitis. The onset of peripheral arthritis coincides with or follows the onset of bowel symptoms in most cases, whereas spondylitis may precede the onset of inflammatory bowel disease by years. HLA-B27 is present in 50% to 75% of cases of spondylitis. No HLA association with inflammatory bowel disease or peripheral arthritis has been consistently found.