Reactive arthritis (Reiter's syndrome with conjunctivitis, urethritis, and diarrhea) ( Fig. 22 ) usually follows a bout of gastroenteritis or urethritis. Implicated organisms include Campylobacter, Shigella, Salmonella, Ureaplasma, and Yersinia species. Affected patients, usually men, often have vesicles and crusted plaques on the penis (circinate balanitis) and erythematous pustules and papules on the palms and soles (keratoderma blennorrhagicum) that can mimic pustular psoriasis. More than 50% of patients have sacroiliitis, correlating with the presence of HLA-B27 antigen, but few patients have the classic triad of urethritis, conjunctivitis, and arthritis.
Potential oral or head and neck findings of bulimia and anorexia include dental erosion, xerostomia, increased rate of caries, and sialadenosis. Vomiting exposes teeth to acidic gastric contents, which leads to enamel erosion. The erosion pattern tends to involve the lingual surfaces of the maxillary anterior teeth ( Figure 12 ) and, in severe cases, the buccal surfaces of the posterior mandibular teeth. 39 Patients may have dental sensitivity to cold or sweet stimuli. Xerostomia may be caused by medications often used by patients with bulimia or anorexia (., antidepressants, diuretics, laxatives), as well as by vomiting and excessive exercise. 40 Because the buffering and cleansing properties of saliva are important for prevention of tooth decay, xerostomia leads to increased caries risk. Additionally, sialadenosis affects approximately 25 percent of patients with bulimia; bilateral parotid enlargement is the most common presentation. 41