1.
Performance of 4 Creatinine-based Equations in Assessing Glomerular Filtration Rate in Adults with Diabetes.
Zafari, N, Lotfaliany, M, O'Keefe, GJ, Kishore, K, Torkamani, N, MacIsaac, RJ, Churilov, L, Ekinci, EI
The Journal of clinical endocrinology and metabolism. 2021;(1):e61-e73
Abstract
AIMS: To evaluate diagnostic performance of glomerular filtration rate (GFR) estimated by modification of diet in renal disease (MDRD), chronic kidney disease epidemiology collaboration (CKD-EPI), full age spectrum (FAS), and revised Lund-Malmö (r-LM) equations in adults with diabetes. METHODS Individuals were included in this cross-sectional study if they had at least 1 measurement of technetium-99m diethylenetriamine-pentaacetic acid (99mTc-DTPA) GFR (mGFR) and serum creatinine (1487 patients with 2703 measures). GFR calculated by estimation equations was compared with mGFR. Diagnostic performance was assessed using concordance correlation coefficient (CCC), bias, precision, accuracy, reduced major axis regression (RMAR), and Bland-Altman plot. Analysis was repeated in subgroups based on sex, diabetes type, Hemoglobin A1C, and GFR level. RESULTS Of all patients, 1189 (86%) had type 2 diabetes. Mean mGFR, MDRD, CKD-EPI, FAS, and revised Lund-Malmö eGFR were 66, 72, 74, 71, and 67 mL/min/1.73m2, respectively. Overall, the r-LM had the highest CCC (0.83), lowest bias (-1.4 mL/min/1.73 m2), highest precision (16.2 mL/min/1.73 m2), and highest accuracy (P10 = 39%). The RMAR (slope, intercept) in r-LM, FAS, MDRD, and CKD-EPI was 1.18, -13.35; 0.97, -2.9; 1, -6.4, and 1.04, -11.3, respectively. The Bland-Altman plot showed that r-LM had the lowest mean difference and the narrowest 95% limit of agreement (-1.0, 54.1 mL/min/1.73 m2), while mean difference was more than 5-fold higher in FAS, MDRD, and CKD-EPI (-5.2, -6.3, and -8.2, respectively). CONCLUSIONS In adults with diabetes the revised Lund-Malmö performs better than MDRD, CKD-EPI, and FAS in calculating point estimates of GFR.
2.
Hypocalcaemia following denosumab in prostate cancer: A clinical review.
Lau, LH, Cliff, ERS, Wong, V, Wong, H, Torkamani, N, Eer, A, Weickhardt, A, Grossmann, M
Clinical endocrinology. 2020;(6):495-502
Abstract
OBJECTIVES Denosumab is often used in men with advanced prostate cancer to prevent skeletal-related events, but can be associated with severe hypocalcaemia. Our objective was to review the pathophysiology, identify risk factors and provide recommendations for prevention and management of denosumab-associated hypocalcaemia. DESIGN We reviewed the literature regarding denosumab-associated severe hypocalcaemia, defined as necessitating hospitalization for intravenous calcium treatment, in the context of prostate cancer. PATIENTS Men with prostate cancer with severe denosumab-associated hypocalcemia. RESULTS We identified 20 men with prostate cancer with severe denosumab-associated hypocalcemia, including the present case. Median age (range) was 70 years (45-86). All had skeletal metastases and presented with symptomatic hypocalcemia 16 days (4-35) after the initial (n = 18) or second (n = 2) denosumab treatment, with a serum total calcium of 1.36 mmol/L (1.13-1.91). The key risk factor was presence of active osteoblastic metastases, evidenced by elevated serum alkaline phosphatase, 838 U/L (58-2620) and supportive imaging. Other risk factors reported in some men included vitamin D deficiency (<50 nmol/L), 25-OH vitamin D 44 nmol/L (22-81), renal impairment, serum creatinine 103 μmol/L (62-1131) and hypomagnesaemia, 0.82 mmol/L (0.29-1.20). Men received intravenous calcium infusions for 16 days (1-90), and median total intravenous elemental calcium requirements were 3.17 g (0.47-26.65). CONCLUSIONS Denosumab treatment in men with metastatic prostate cancer can be associated with life-threatening hypocalcaemia requiring prolonged hospitalization for intravenous calcium treatment. Modifiable risk factors should be corrected before denosumab administration. In men with active osteoblastic metastases, consideration should be given to delay denosumab treatment until underlying disease activity is controlled, and/or be administered with close monitoring and proactive treatment with calcium and calcitriol.