Screening for ketonemia in patients with diabetes.

STUDY OBJECTIVES: To determine the sensitivity and specificity of the urine ketone dip test as a screening test for ketonemia in hyperglycemic patients and to compare the performance of the urine ketone dip test with the anion gap and serum bicarbonate level. METHODS: This was a prospective study conducted in an urban, university-affiliated public hospital emergency department. Inclusion criteria consisted of (1) patients with known diabetes and hyperglycemia (glucose level>200 mg/dL) and any complaint of illness, or (2) patients with hyperglycemia and symptoms of undiagnosed diabetes mellitus. Urine ketone dip test, serum ketone, and electrolyte levels were determined on all subjects. Sensitivity, specificity, and predictive values along with 95% confidence intervals (CIs) were calculated. RESULTS: The study group comprised 697 patients, including 98 patients with diabetic ketoacidosis (DKA) and 88 with diabetic ketosis (DK). The sensitivity, specificity, positive, and negative predictive values of the urine ketone dip test for the detection of DKA were 99% (95% CI 97% to 100%), 69% (95% CI 66% to 73%), 35% (95% CI 29% to 41%), and 100% (95% CI 99% to 100%), respectively. For DKA and DK, the sensitivity, specificity, positive, and negative predictive values of the urine ketone dip test were 95% (95% CI 90% to 97%), 80% (95% CI 76% to 83%), 63% (95% CI 57% to 69%) and 98% (95% CI 96% to 99%). The anion gap and serum bicarbonate level were less sensitive but more specific than the urine ketone dip test for the detection of DKA and DK. CONCLUSION: The urine ketone dip test has high sensitivity for detecting DKA and a high negative predictive value for excluding DKA in hyperglycemic patients with diabetes with any symptoms of illness. The urine ketone dip test is a better screening test for DKA and DK than the anion gap or serum bicarbonate.

Urine ketone dip test as a screen for ketonemia in diabetic ketoacidosis and ketosis in the emergency department.

STUDY OBJECTIVE: To determine the sensitivity of the urine ketone dip test (UKDT) for the detection of ketonemia in patients with diabetic ketoacidosis (DKA) and diabetic ketosis (DK) in the ED. METHODS: We conducted a retrospective chart review in the ED of an urban, university-affiliated county teaching hospital. The study population comprised patients seen in the ED during 1994 and 1995 with a discharge diagnosis of DKA or DK and underwent urinalysis within 4 hours of the initial serum electrolyte and ketone determinations. We calculated test sensitivity, along with 95% confidence intervals (CIs). RESULTS: One hundred forty-eight patients with 223 occurrences diagnosed as DKA or DK were seen in the ED during the study period. One hundred fourteen patients with 146 occurrences of DKA or DK met all inclusion criteria; these patients made up the study group. There were 99 cases of DKA and 47 cases of DK. The sensitivity of the UKDT for the detection of ketonemia in all patients with DKA or DK was 97% (95% CI, 94% to 99%). In the subgroup of patients with DKA, the sensitivity of the UK was 97% (95% CI, 92% to 99%). For patients with DK, the sensitivity of the UK was 98% (95% CI, 89% to 99%). CONCLUSION: The UKDT is highly sensitive for the presence of serum ketones in patients with DKA and DK. Prospective study is suggested to determine the specificity of the UKDT in this application and to validate its use as a screening tool for the detection of ketonemia in DKA and DK.