diagnosis
Last reviewed 01/2018
Diagnosis is by demonstrating renal tubular acidosis, hypokalaemia, hypophosphataemia, glycosuria, proteinuria and amino-aciduria with normal plasma amino acids, including cystine.
Slit lamp examination reveals refractile corneal crystals. Intracellular storage of cystine may also be seen seen in bone marrow, lymph node, conjunctival or rectal biopsy.