lesions, glaucoma, and loss of vision. There was no previous uveitis. Scleritis was the initial manifestation whose study led to the diagnosis of UC in both patients.

Episcleritis

Episcleritis is common in IBD [271, 274]. Knox et al. [271] reported that the presence of episcleritis in UC is a good indicator to consider changing the diagnosis to CD because, in their experience, episcleritis is associated only with CD. Although episcleritis may appear prior to the onset of gut manifestations [276], it usually occurs after some years of bowel disease, especially during periods of disease exacerbation [274]. Episcleritis is more frequently seen in patients with arthritis and other extraintestinal manifestations [269, 271, 274].

In our own series of 85 patients with episcleritis, two patients had IBD (2.35%); one patient had CD and one patient had UC. All were female, with a mean age of 55 years, who developed recurrent simple and nodular episcleritis, respectively, an average of 6 years (range, 5Ð7 years) after the diagnosis of CD and UC. There were no corneal lesions, anterior uveitis, glaucoma, or decrease in visual acuity.

Keratitis

Keratitis in IBD, speciÞcally in CD, consists of either peripheral small round subepithelial gray inÞltrates, probably due to acute inßammation, or peripheral nebulous subepithelial inÞltrates, probably due to scarring [278].

6.1.6.4 Laboratory and Joint Radiologic Findings

Inßammatory bowel disease may account for anemia, leukocytosis, elevated sedimentation rate, and evidence of malabsorption or protein loss. Rheumatoid factor and ANA tests are negative. Joint ßuid is usually at least mildly inßammatory. Of patients with AS and IBD, 30Ð70% carry the HLA-B27 gene, compared with >90% of patients with AS alone and 50Ð70% of those with AS and psoriasis. Hence, deÞnite or probable AS in an HLA-B27-negative individual in the absence of psoriasis should prompt a search for

occult IBD. Radiographic changes in the axial skeleton are the same as in uncomplicated AS, that is, minimal destructive signs, such as cystic changes, narrowing of the joint space, and erosions. Erosions are uncommon in peripheral arthritis but may occur, particularly in the metatarsophalangeal joints.

6.1.6.5 Diagnosis

Diarrhea and arthritis are both common conditions that can coexist for a variety of reasons. ReA and IBD-associated arthritis are the most common causes. Rare causes include celiac disease, blind loop syndromes, and WhippleÕs disease.

Diagnosis of CD is made on the basis of clinical signs and symptoms combined with characteristic X-ray Þndings, including deep (collar button) ulcerations, long strictured segments (string sign), and skip areas. Colonoscopy may be helpful when there is colonic involvement, and biopsies may show granuloma formation with transmural inßammation [279].

Diagnosis of UC is based on clinical presentations along with the exclusion of infectious, parasitic, and neoplastic etiologies. Proctoscopy may reveal friability, edema, ulcerations, and mucopurulent exudate. Characteristic X-ray Þndings include lack of haustral markings, Þne serrations, large ulcerations, and pseudopolyps. Biopsies show microabcesses of the crypts of LieberkŸhn and macroscopic ulcerations; the inßammatory response is limited to the mucosa.

6.1.7Relapsing Polychondritis

Relapsing polychondritis (RP) is an uncommon multisystem disease of unknown cause. Cartilage and other tissues with a high concentration of glycosaminoglycans are the main target of damage. These include the pinnae of the ears, nasal cartilage, eustachian tubes, larynx, trachea, bronchi, joints, vessels, and sclera [280].

6.1.7.1 Epidemiology

Relapsing polychondritis is most frequent in the fourth decade of life, occurs predominantly in Whites, and does not have sexual predilection.