Serum protein electrophoresis, complete blood count (CBC), and general screening for albumin/globulin and calcium levels are performed when clinical suspicion of immunoglobulin excess arises. Further testing for systemic evaluation depends on clinical suspicion and the initial findings.

MANAGEMENT No ophthalmic treatment is needed unless the amorphous depositions interfere with vision and need to be removed with LK. Crystals will resolve slowly after successful treatment of an underlying malignancy.

Noninflammatory Disorders of Connective Tissue

Many musculoskeletal and connective tissue diseases affect the cornea. The corneal manifestations of these diseases are detailed in the Appendix at the end of this chapter.

Ehlers-Danlos Syndrome

Ehlers-Danlos syndrome (EDS), a heterogeneous group of diseases, is characterized by hyperextensibility of joints and skin, easy bruisability, and formation of “cigarette paper” scars. It was discussed briefly in Chapter 9 in connection with blue sclera.

PATHOGENESIS The many (more than 20) known types of EDS are classified as autosomal dominant and recessive and X-linked recessive. Multiple genetic loci have been identified. Specific defects occur in collagen type I and III synthesis, and there can be lysyl hydroxylase deficiency.

CLINICAL FINDINGS EDS type VI (EDS VI), or the ocular-scoliotic type, is autosomal recessive and associated with only moderate joint and skin extensibility, brittle cornea easily ruptured on minor trauma, blue sclera, keratoconus and keratoglobus, and severe scoliosis. Type VIA shows lysyl hydroxylase deficiency, but type VIB shows normal production of lysyl hydroxylase.

LABORATORY EVALUATION Traditionally, the clinical diagnosis is confirmed by an insufficiency of hydroxylysine on analysis of hydrolyzed dermis and/or reduced enzyme activity in cultured skin fibroblasts. However, the diagnosis can also be confirmed by the altered urinary ratio of lysyl pyridinoline to hydroxylysyl pyridinoline that is characteristic of EDS VI.

MANAGEMENT Recognition of the syndrome and awareness of its association with mitral valve prolapse, spontaneous bowel rupture, and complications of strabismus surgery, and of potential confusion of the brittle cornea with child abuse, are essential. Use of patch grafts for repair of corneoscleral ruptures has been successful. Genetic counseling should be considered.