Emergency metabolic tests
Emergency metabolic tests
When a patient is admitted with a possible inborn error of intermediary metabolism, the following samples are required for metabolic studies.
The vital specimen: consider catheterisation or bladder tap
| Urine | at least 3 mL | Random sample, frozen or on ice. No added preservative. and transport on dry ice |
| For amino acid profile, organic acid profile, acylglycines, orotic acid etc. |
Next two most important samples
| Plasma | at least 1 mL | Lithium Heparin (not EDTA). Contact your laboratory as the sample needs to be separated and spun down within 20 minutes, then frozen at -80 C and transport on dry ice. |
| For acylcarnitines, carnitine, quantitative amino acids, very long chain fatty acids, etc. | ||
| Dried blood spots | at least 1 mL | Whole blood Lithium Heparin (not EDTA). Spot onto all circles of 3 or 4 Guthrie cards or store at +4 C. Transport cards in a paper envelope, not a platic bag. Transport whole blood on ice. |
| For acylcarnitine profile, galactose-1-phosphate uridyltransferase screen, DNA/PCR etc. |
If the patient is hypoglycaemic
| Plasma | Add a request to your laboratory for free fatty acids, 3 hydroxybutyrates. |
If the patient is to have a lumbar puncture
| CSF | at least 250 µL | Collected within 1 hour of the matching plasma sample. MUST be free of red cells. Freeze and store at -80 C and transport on dry ice. |
| For quantitative amino acids, especially glycine or homocarnosine. |