No need for routine glycosuria/proteinuria screen in pregnant women ORIGINAL RESEARCH

Objective More than 22 million prenatal visits occur in the US each year. Each pregnant woman averages 7 visits. Most include urine testing for glucose and protein to screen for gestational diabetes and preeclampsia. Is there sufficient scientific evidence to support this routine practice? Methods We searched Medline (1966– 2004), the Cochrane review, AHRQ National Guideline Clearinghouse, the Institute for Clinical Systems Improvement, and Google, searching for studies on proteinuria or glycosuria in pregnancy. The reference list of each article reviewed was examined for additional studies, but none were identified. We found 6 studies No need for routine glycosuria/proteinuria screen in pregnant women ORIGINAL RESEARCH Routine glycosuria/proteinuria screen in pregnant women " High ascorbic acid intake or high urinary ketone levels can cause false-positive glycosuria results VOL 54, NO 11 / NOVEMBER 2005 979 w w w. j f p o n l i n e . c o m FAST TRACK of determining results, or definitions of abnormal, each was evaluated separately. What the evidence shows Found at some point in about 50% of women, glycosuria is believed to be due to an increased glomerular filtration rate. The renal threshold for glucose is highly variable and may lead to a positive test result for glycosuria despite a normal blood sugar. High intake of ascorbic acid or high urinary ketone levels may result in false-positive results. There have been 4 published studies designed to assess the value of glycosuria as a screen for gestational diabetes mellitus. All used urine dipsticks (TABLE 1). Watson: Urine test a poor screening instrument In an observational prospective study of 500 women, Watson evaluated glycosuria (trace, ≥100 mg/dL) detected on 2 separate prenatal visits (17% of women) as a predictor of gestational diabetes. Gestational examinations. Today, when our care of patients is squeezed by both time and monetary constraints, we have a rare opportunity to make office visits more productive and to save patients the burden of unnecessary work-ups. Review methods We searched Medline from 1966 to September 2004 for English language articles using keyword searching for “proteinuria” or “glycosuria” and “prenatal” or “pregnancy. ” We explored the Cochrane review, AHRQ National Guideline Clearinghouse, the Institute for Clinical Systems Improvement, and Google. The reference list of each article reviewed was examined for additional studies, but none were identified. All 6 identified studies that investigated glycosuria as a predictor for gestational diabetes mellitus or proteinuria as a predictor for preeclampsia are reviewed in this analysis. One study examined both. Because every study used different dipstick methods TA B L E 1 DIAGNOSTIC STUDY SENSITIVITY SPECIFICITY LR+ LR– PREVALENCE ODDS RATIO TEST QUALITY N (95% CI) (95% CI) (95% CI) (95% CI) PV+ PV– OF GDM (95% CI) ≥2 determinations 2b 500 27% 83% 1.6 0.87 7% 96% 4.4% 1.9 Urine dipstick (13%–48%) (80%–87%) (0.8–3.4) (0.7–1.1) (0.7–5.0) glycosuria ≥100 mg/dL [trace] ≥2 determinations 2b 2745 7% 98% 4.5 0.94 13% 97% 3.1% 4.9 Urine dipstick (3%–15%) (98%–99%) (2.0–10.5) (0.9–1.0) (2.0–11.8) glycosuria ≥250 mg/dL [1+] ≤ 1 determination 2b 607 36% 98% 20 0.65 27% 99% 1.8% 30.4 Urine dipstick (15%–64%) (97%–99%) (7.4–52.3) (0.41–1.0) (7.8–119) glycosuria ≥100 mg/dL [1+] 1 determination 2b 766 11% 93% 1.5 . 96 7% 95% 4.1% 1.6 Urine dipstick (4%–25%) (91%–95%) (0.6–4.0) (0.9–1.1) (0.5–4.6) glycosuria >75–125 mg/dL LR+, positive likelihood ratio; LR–, negative likelihood ratio; PV+, probability of disease given a positive test; PV–, probability of disease given a negative test; GDM, gestational diabetes mellitus; CI, confidence interval. Accuracy of glycosuria for predicting gestational diabetes mellitus