TABLE 6.
Effect of delayed plating of urine specimens kept refrigerateda
| Study (reference) | Threshold (no. of CFU/ml) | NSG present |
SG present |
||
|---|---|---|---|---|---|
| No. of specimens subjected to immediate culture | % change from no. after delay | No. of specimens subjected to immediate culture | % change from no. after delay | ||
| Weinstein (37) | ≥105 | 758 | +0.9b | 111 | −6.3b |
| Hubbard et al. (34) | >105 | 74 | 0 | 26 | 0 |
a
Both studies were given a quality rating of fair. NSG, nonsignificant growth; SG, significant growth. Both studies immediately cultured fresh specimens and specimens that had been kept under refrigeration for 24 h.
b
There were 7 fewer patient samples available for analysis with delayed culture (862 patient pairs versus 869); percentages of increase were calculated assuming 869 pairs.