tandem mass spectrometry screen
Specimen Collection Protocols - Urine random preferably send to lab on ice and freeze on arrival in the lab. Please note time of collection and time of freezing the urine sample on request form
NON-acidified samples for urine cystine are UNACCEPTABLE as cystine can crystallize out and cause a falsely lowered result. For initial cystine screen we prefer a random urine but can analyse a 24 hour ACIDIFIED urine.
Note time sample was frozen on request form
Tandem mass spectrometry performed weekly
A brief clinical history is required.
For known patients with cystinuria we require a 24 hour ACIDIFIED urine see Cystine quantitation