Altogether 23 male patients with Reiter's disease (RD) were followed-up in an arid zone. An interstitial syndrome was diagnosed in addition to the urethro-oculo-synovial syndrome. In one group (14 patients) RD followed acute enterocolitis (dysentery in 3 cases and 9 cases of unknown etiology). Halprovias were found in 5 patients, colon lesion in 12 patients. In the other group (9 patients) halprovias were found in 4 patients. The signs of enterocolitis, pathological microbial flora in the stool and changes in the colon mucosa were absent. An assumption was made of pathogenetic relationship of the urethro-oculo-synovial and intestinal syndromes in RD. A more serious RD course was noted in this combination of syndromes.