Clinical background:
Most patients with renal stones have a history of recurrent stone formation. Biochemical analysis of blood and urine is performed in order to identify the cause of stone formation, so patients may undergo guided treatment.
Minimum volume paediatric:
Refer to individual test on the website
Minimum volume adult:
Refer to individual test on the website
Special requirements:
Samples should be collected at least 6 weeks after surgery or lithotripsy to avoid contamination of the urine.
Other info :
Baseline biochemistry for first-stone investigation:
| Sample | Tests | Specimen container |
| Blood | Urea and creatinine Calcium and albumin Sodium and potassium Bicarbonate Uric acid CRP | SST (gold top) serum sample |
| Urine(random sample) | Dipstick for:- Red and white cells- Nitrite- pH | Universal container – performed on the ward |
| Calcium/creatinine ratio Cystine/creatinine ratio | Universal container | |
| Urine microscopy and culture | Universal container |
– Screen for recurrent stones formers:
| Sample | Tests | Specimen container |
| Blood | Urea and creatinine Sodium and potassium Calcium and albumin Uric acid Phosphate Bicarbonate | SST (gold top) serum sample |
| PTH (if hypercalcaemia is present) | EDTA (purple top) | |
| Vitamin D (if hypercalcaemia is present) | SST (gold top) serum sample | |
| Urine Adult: 24 hours collection/ Children: random sample | Volume Calcium Oxalate Citrate Cystine Creatinine Sodium | Plain container |
| Urine (random sample) | Dipstick for: – pH | Universal container – performed on the ward |
| Microbiology | Universal container |