Which of the following conditions is associated with darkening of urine on standing?
Characteristic sign of alkaptonuria is darkening of urine on standing, especially if the urine is alkaline. Ref: Harrison's 16th Edition, Page 2334; Essential Pediatrics, OP Ghai - 6th Edition, Page 610; Nelson's Paediatrics 17th Edition, Page 403; Lippincotts 3rd Edition, Page 272.
Alkaptonuria
Cystinuria
Fabry's disease
Tyrosinemia