Classic nephropathic cystinosis as an adult disease

Abstract

Objective: To delineate the clinical characteristics of infantile nephropathic cystinosis in adult patients who have undergone renal transplantation.

Design: Case series.

Setting: Clinical research unit.

Patients: All 36 adult patients with nephropathic cystinosis referred to the National Institutes of Health.

Outcome measures: Longevity, growth, renal allograft survival, visual acuity, endocrine insufficiency, myopathy and swallowing dysfunction, cerebral calcifications, and occupational status.

Results: Of the 36 patients, seven were dead, five with functioning allografts. The 1-year and 5-year graft survival rates for 30 cadaveric allografts were 90% and 75%, respectively. The patients' mean height and weight were severely retarded. Five patients were legally blind, and three others had severely impaired vision in one eye. Thirty-one (86%) of 36 patients required thyroid hormone replacement therapy. One third had a distal myopathy, and 21 had moderate to severe swallowing abnormalities. Eight patients had cerebral calcifications on computed tomographic scan. Despite these complications, the sighted patients engaged in a normal variety of occupations. Only 11 patients were receiving adequate cystine-depleting therapy with cysteamine (mercaptamine) or phosphocysteamine.

Conclusions: Adult patients with nephropathic cystinosis suffer serious complications of the disease.