The role of point-of-care blood testing for ketones in the diagnosis of diabetic ketoacidosis.

BACKGROUND: Urine dipstick testing for ketones is widely used when diabetic ketoacidosis (DKA) is suspected in patients with hyperglycaemia. If urinary ketones are positive, patients are referred for further management--often inappropriately, as the test is a poor surrogate for plasma ketones. Plasma beta-hydroxybutyrate (ß-OHB) levels>3 mmol/L are diagnostic of DKA, while levels<1 mmol/L are insignificant. OBJECTIVES: To evaluate a hand-held electrochemical (point-of-care testing; POCT) ketone monitor and compare it with the gold-standard manual enzymatic method (MEM) for detection of plasma ketones. METHODS: In a prospective and comparative study, we evaluated the measurement of ß-OHB by means of POCT and the MEM in 61 consecutive samples from patients with suspected DKA at Tygerberg and Karl Bremer hospitals, Cape Town, South Africa. Capillary (for POCT) and plasma samples (for the MEM) were obtained simultaneously and compared for accuracy. Precision was assessed with control samples. RESULTS: The POCT method was precise (coefficient of variation <4.5%), and there was a good correlation between the two methods (r=0.95). Regression analysis showed a proportional bias, with POCT reading higher than the MEM. However, when assessed at the relevant medical decision limits (ß-OHB>3 mmol/L and <1 mmol/L), the total allowable error (bias+imprecision) was not exceeded. Patients will therefore still be classified correctly. The POCT method had a sensitivity of 100% and specificity of 89% for DKA (ß-OHB>3 mmol/L), while at levels<1 mmol/L sensitivity was 100% and specificity 87.5%. CONCLUSION: The POCT device provides an accurate and precise result and can be used as an alternative to the MEM in the diagnosis of DKA.

Skeletal consequences of hormone therapy discontinuance: a systematic review.

UNLABELLED: Although hormone therapy protects against bone loss after menopause, currently it is not recommended once menopausal symptoms have subsided. We reviewed randomized clinical trials to quantify bone loss after stopping hormone therapy and summarize treatment options for women who discontinue hormone treatment. We conducted a search of MEDLINE and EMBASE for randomized, controlled trials measuring bone mineral density (BMD) after hormone therapy discontinuation. Other known published and unpublished data were also included. Eleven studies fulfilled the search criteria. In each, bone loss was rapid after stopping hormone therapy, with BMD declines ranging from 2.3% to 6.2% in the first year. Increases in bone turnover markers also occurred rapidly when hormone therapy was stopped. Limited data addressing treatment after hormone therapy is stopped exist; only 2 studies specifically evaluated therapy to protect bone after hormone discontinuation. Taken together, these 2 studies demonstrate that alendronate produced significant increases relative to placebo in spine, hip, and total body BMD in women with low bone density who had discontinued hormone therapy within the past 3 months, preventing the rapid bone loss seen on discontinuation of hormone therapy. Among treatment options for preventing bone loss on discontinuation of hormone therapy for which randomized clinical trial data are available, alendronate prevented bone loss or increased bone density in postmenopausal women with low bone density. Women who are discontinuing hormone therapy should be counseled about potential bone loss and effective treatment options. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to state that discontinuation of replacement menopausal hormone therapy, which protects against bone loss, is not recommended after menopause symptoms have subsided; recall that it may accelerate bone loss; and explain that there is bone loss preventive treatment for women after discontinuation of hormone therapy.

Alendronate prevents loss of bone density associated with discontinuation of hormone replacement therapy: a randomized controlled trial.

BACKGROUND: Many women using hormone replacement therapy (HRT) will discontinue HRT and lose its bone-protective effect. Methods to preserve bone density in these women need to be explored. This multicenter, international, randomized, blinded, 12-month study was conducted to assess the effect of alendronate sodium on bone density in women who had recently discontinued HRT. METHODS: The 144 postmenopausal women included in the study were diagnosed as having low bone mineral density (BMD) and had recently discontinued HRT. They were randomized to receive either a daily dose of 10 mg of alendronate sodium or matching placebo. The main outcome measures were spine, hip, and total body BMD; biochemical markers of bone turnover; and tolerability. RESULTS: Alendronate treatment was associated with a 2.3% mean increase (95% confidence interval [CI], 1.7%-3.0%) in spine BMD compared with a mean loss of 3.2% (95% CI, - 4.6% to - 1.7%) in patients receiving placebo, for a difference of 5.5% (95% CI, 4.2%-6.8%) between alendronate and placebo. Greater hip and total body BMD preservation was also observed with alendronate use. Bone turnover decreased significantly with alendronate (bone-specific alkaline phosphatase levels decreased by 20% and urinary N-telopeptide/creatinine ratio by 47%), but increased in the placebo group (by 18% and 36%, respectively). Alendronate was well tolerated, with no increase in adverse events compared with placebo. CONCLUSIONS: A high rate of bone loss was observed in the first 12 to 15 months after discontinuation of HRT in postmenopausal women with low BMD. Treatment with alendronate increased or maintained both spine and hip BMD and prevented the increase in bone resorption seen with withdrawal of HRT in this population.