Teriparatide Therapy in a 4-Month-Old With Severe Hypoparathyroidism

Teriparatide is a human parathyroid hormone analog approved for the treatment of osteoporosis in adult patients. Its use for hypocalcemia and hypoparathyroidism in the pediatric population is described through case reports and small case series; however, larger studies that demonstrate long-term efficacy and safety are limited. At our institution, a 4-month-old premature (gestational age: 32 weeks) infant with multiple congenital anomalies, functional athymia, and severe hypoparathyroidism and receiving calcitriol, vitamin D, and calcium carbonate supplementation was initiated on subcutaneous injection of teriparatide. During the course of treatment, her calcium carbonate, vitamin D, and calcitriol supplementation requirements substantially decreased. Teriparatide effectively increased serum ionized calcium concentrations and decreased serum phosphorus concentrations in the present case-study over a 6-month period. Teriparatide was well tolerated, and no evidence of hypercalcemia was observed throughout treatment.

Changes in the Relationship between Ionized and Total Calcium in Clinically Healthy Dairy Cows in the Period around Calving

We aimed to establish a model for prediction of iCa from tCa, using multivariable regressions with diverse blood constituents. Blood was taken from 14 cows at days −2, 0, 2, 4, 7, and 14 relative to parturition. Cows were clinically healthy, and no hypocalcaemia prophylaxis and treatment were applied. Total calcium and further parameters were determined from frozen serum. Ionized calcium, blood gases, and electrolytes were determined from heparin-stabilized blood samples. Linear regression between iCa and tCa was estimated. Precision improved only slightly using a multivariable model. Best precision was achieved when estimating the iCa:tCa ratio from other blood constituents. To identify the reason behind the poorly predictive value of tCa for iCa, the relative changes of iCa and tCa around calving were calibrated to the respective values of day −2 (=100%) for each cow. An increase in the iCa:tCa ratio was observed from 0.43 at day −2 to 0.48 at day 0, followed by a gradual decrease towards 0.43 at day 7. We conclude that routine measurement of iCa should be implemented in the diagnosis of hypocalcaemia. An optimized estimate of iCa from tCa with non-esterified fatty acids (NEFA), beta-hydroxybutyric acid, cholesterol, and phosphorous as co-predictors is still poorly satisfying.

Conflicts over calcium and the treatment of covid-19

Several recent studies have provided evidence that use of calcium channel blockers, especially amlodipine and nifedipine, can reduce mortality from Covid-19. Moreover, hypocalcemia (a reduced level of serum ionized calcium) has been shown to be strongly positively associated with Covid-19 severity. Both effectiveness of CCBs as antiviral therapy, and positive associations of hypocalcemia with mortality, have been demonstrated for many other viruses as well. We evaluate these findings in the contexts of virus-host evolutionary conflicts over calcium metabolism, and hypocalcemia as either pathology, viral manipulation, or host defence against pathogens. Considerable evidence supports the hypothesis that hypocalcemia represents a host defence. Indeed, hypocalcemia may exert antiviral effects in a similar manner as do CCBs, through interference with calcium metabolism in virus-infected cells. Prospective clinical studies that address the efficacy of CCBs and hypocalcemia should provide novel insights into the pathogenicity and treatment of Covid-19 and other viruses.

Hospital-Acquired Serum Ionized Calcium Derangements and Their Associations with In-Hospital Mortality

Background: The objective of this study was to report the incidence of in-hospital serum ionized calcium derangement and its impact on mortality. Methods: We included 12,599 non-dialytic adult patients hospitalized at a tertiary medical center from January 2009 to December 2013 with normal serum ionized calcium at admission and at least 2 in-hospital serum ionized calcium values. Using serum ionized calcium of 4.60–5.40 mg/dL as the normal reference range, in-hospital serum ionized calcium levels were categorized based on the presence of hypocalcemia and hypercalcemia in hospital. We performed logistic regression to assess the relationship of in-hospital serum ionized calcium derangement with mortality. Results: Fifty-four percent of patients developed new serum ionized calcium derangements: 42% had in-hospital hypocalcemia only, 4% had in-hospital hypercalcemia only, and 8% had both in-hospital hypocalcemia and hypercalcemia. In-hospital hypocalcemia only (OR 1.28; 95% CI 1.01–1.64), in-hospital hypercalcemia only (OR 1.64; 95% CI 1.02–2.68), and both in-hospital hypocalcemia and hypercalcemia (OR 1.73; 95% CI 1.14–2.62) were all significantly associated with increased in-hospital mortality, compared with persistently normal serum ionized calcium levels. Conclusions: In-hospital serum ionized calcium derangements affect more than half of hospitalized patients and are associated with increased in-hospital mortality.

Osteocalcin as a Predictor of Body Composition in Healthy Adults

Objectives The objectives of this study were to determine if body composition and nutrient status are dependent on serumosteocalcin concentrations in healthy adults. Methods Adults 20 to 70 years of age completed fasting blood sampling to measure serum ionized calcium concentrations, serum ionized magnesium concentrations, and serum total osteocalcin concentrations. Dual Energy X-Ray Absorptiometry was also completed to measure body composition variables including body mass index (BMI), total fat mass, total fat freemass, total lean mass, android fat, gynoid fat, trunk fat, and visceral adipose tissue. Results A sample of 60 women and 78 men with a median age of 33.0 (21.0) years were categorized into two groups accordingto the median osteocalcin concentration measured: low osteocalcin (12.11 ± 2.72 ng/mL), and high osteocalcin (26.80 ± 9.72 ng/mL). Means, standard deviations, medians and interquartile ranges were calculated and independent t-tests, and Mann Whitney U tests were conducted to determine differences between groups in body composition variables. Total fat mass, total fat percentage, android fat, trunk fat, and trunk fat percentage were all significantly higher, and totalfat free mass, fat free mass percentage, total lean mass, lean mass percentage, serum ionized calcium concentrations, and serum ionized magnesium concentrations were all significantly lower (P < 0.05) in the low osteocalcin groupcompared to the high osteocalcin group. There were no differences (P >0.05) between groups in weight, gynoid fat, visceral adiposity tissue, or visceral adiposity tissue percentage. Conclusions The results of this study provide preliminary evidence that serum osteocalcin concentrations can predict bodycomposition. Interventional studies should consider methods to alter osteocalcin concentrations through vitamin ormineral supplementation as a means to improve body composition in adults. Funding Sources American Heart Association; Drexel University.