From the Research
For a pregnant patient with persistent glycosuria despite a normal 1-hour glucose tolerance test, the next step in management should be to perform a 2-hour oral glucose tolerance test (OGTT) with 75g glucose, as recommended by the WHO criteria 1. This more comprehensive test involves measuring blood glucose levels at fasting and 1-hour and 2-hour intervals after consuming a 75-gram glucose solution. Persistent glycosuria during pregnancy can indicate gestational diabetes that wasn't detected by the initial screening test. The 2-hour OGTT is considered a diagnostic standard, as it has higher sensitivity than the 1-hour test. If the 2-hour OGTT is normal, other causes of glycosuria should be investigated, including a lower renal threshold for glucose during pregnancy (which can be physiologic), urinary tract infection, or other renal conditions. While awaiting further testing, the patient should be advised to follow a balanced diet, moderate physical activity, and regular prenatal care. Glycosuria warrants follow-up because undiagnosed gestational diabetes can lead to complications such as macrosomia, neonatal hypoglycemia, and increased risk of cesarean delivery. Key aspects of management include:
- Monitoring blood glucose levels to maintain them within the therapeutic range (fasting < 95 mg/dl and 1 hour after meals < 140 mg/dl) 1
- Providing nutritional counseling and encouraging physical activity to moderate intensity levels if not contraindicated 1
- Considering insulin therapy if blood glucose levels cannot be maintained in the therapeutic range 1
- Regular obstetric examinations, including ultrasound examinations, to minimize maternal and fetal/neonatal morbidity and perinatal mortality 1