Discussion | Cystinosis is caused by the accumulation of free cystine within lysosomes. 1 Cystine is derived from protein degradation within the lysosome and is normally transported through the lysosomal membrane to the cytosol where it is transformed into cysteine and reused. 5 In cystinosis, a mutation in the CTNS gene (on chromosome 17p13), 6 which encodes cystinosin, leads to a defect in the transport system. The low solubility of cystine leads to the precipitation of intracellular needle-shaped crystals as lysosomal cystine levels rise. 3 The accumulation of cystine in various tissues in the body has been known to cause renal failure as well as extrarenal effects leading to ocular, hepatic, thyroid, pancreatic, muscular, dental, gonadal, and neurologic tissue damage. 1,3 However, we know of only 3 prior reports of cutaneous accumulation of cystine crystals in patients with cystinosis. The first 2 published reports described subcutaneous infiltration of a palpable amorphous material with skin atrophy and telangiectasia mimicking premature aging 2 and scattered small erythematous hyperkeratotic macules and papules on sunexposed areas. 3 The third published report involved normalappearing skin on the forearms of patients with infantile cystinosis examined with in vivo reflectance confocal microscopy. 4 To our knowledge, the present case report is the first to describe multiple skin-colored, dome-shaped, firm facial papules in a patient with long-term cystinosis. A definitive diagnosis of cystinosis can be made based on an elevated cystine content in peripheral blood leukocytes. 1 Early detection of cystinosis is crucial because early treatment with oral cysteamine improves growth and survival, prevents hypothyroidism, reduces ocular impairment, and can preserve renal function. 1 Given the improved prognosis for patients with cystinosis who receive renal transplantation and/or cysteamine therapy, the prevalence of extrarenal effects, including cutaneous manifestations, may become more apparent over time. Finally, examination of biopsy specimens under electron microscopy may be required to accurately diagnosis cutaneous cystinosis.