Serum Calcium Research Articles

Causal association of serum calcium, phosphate, vitamin D, parathyroid hormone, and FGF23 with the risk of aortic stenosis

Abstract Aim Disorders of mineral metabolism, including elevated levels of serum calcium, phosphate, 25-hydroxyvitamin D (25OH-VitD), parathyroid hormone (PTH), and fibroblast growth factor 23 (FGF23), have been reported in patients with calcific aortic valve stenosis (CAVS). However, evidence of the causal role of mineral metabolism in CAVS is still lacking. We aimed to investigate the causality between mineral metabolism and CAVS. Methods A systematic pipeline combining Mendelian randomization (MR), Steiger directionality test, colocalization analysis, protein-protein network, and enrichment analysis was applied to investigate the causal effect. Genome-wide association study (GWAS) and protein quantitative trait loci data for mineral metabolism markers were extracted from large-scale meta-analyses. Summary statistics for CAVS were obtained from two independent GWAS datasets as discovery and replication cohorts (n=374,277 and 653,867). Results In MR analysis, genetic mimicry of serum FGF23 elevation was associated with increased CAVS risk [ORdiscovery=3.081 (1.649-5.760), Pdiscovery=4.21×10-4; ORreplication=2.280 (1.461-3.558), Preplication=2.82×10-4] without evidence of reverse causation (Psteiger=7.21×10-98). Strong colocalisation association with CAVS was observed for FGF23 expression in the blood (PP.H4 = 0.96). Additionally, we identified some protein-protein interactions between FGF23 and known CAVS causative genes. Serum calcium, phosphate, 25OH-VitD, and PTH failed to show causal effects on CAVS at Bonferroni-corrected significance (all P>0.05/5=0.01). Conclusions Elevated serum FGF23 level is a causal risk factor for CAVS, and its mechanism of action in CAVS development may be independent of its function in regulating mineral metabolism. Hence, FGF23 may serve as a circulating marker and a promising preventive target for CAVS, warranting further investigation.

Metabolomic fingerprinting of milk fever cows: Pre- and postpartum metabolite alterations.

Milk fever (MF), a metabolic disorder in dairy cows characterized by low blood calcium concentrations postpartum, is well-recognized clinically. However, comprehensive data on the alteration of metabolites associated with this condition remains sparse. Delineate serum metabolite profiles and metabolic pathways preceding, coinciding with, and after the onset of MF. Twenty-six cows, including 20 healthy cows and 6 cows initially affected by MF. Because of culling, the number of MF-affected cows decreased to 4 at MF week, +4 weeks, and +8 weeks postpartum. A nested case-control longitudinal study was conducted, with blood samples collected at -8 and -4 weeks prepartum, MF week, and +4 and +8 weeks postpartum. Serum analysis utilized direct injection/liquid chromatography/tandem mass spectrometry (DI/LC/MS/MS) techniques. Key findings included the identification of diverse metabolites such as hexose, amino acids, phosphatidylcholines, lysophosphatidylcholines, and sphingomyelin, which varied between studied groups (P < .05). The most marked metabolic alterations were observed 4 weeks prepartum. In total, 42, 56, 38, 29, and 24 metabolites distinguished the MF group at the respective time points (P < .05). Additionally, 33 metabolic pathways, including amino acid, antioxidant metabolism, fatty acid degradation, and carbohydrate processing, were impacted (P < .05). Metabolic disruptions in dairy cows begin several weeks before the clinical manifestation of MF and persist up to 8 weeks postpartum. These findings emphasize the complexity of MF, extending beyond only hypocalcemia and indicate the necessity for preemptive monitoring in dairy herd management.

Arterio-Venous Fistula Calcifications—Risk Factors and Clinical Relevance

(1) Background: Arterio-venous fistulas (AVFs) are considered the gold-standard vascular access (VA) in patients on maintenance hemodialysis (HD) therapy. AVF calcifications represent a less studied VA related complication, even though HD patients are at a higher risk for extraosseous calcifications. The aim of this study is to assess the prevalence and risk factors of AVF calcifications, as well as the 5-year impact on AVF functionality and on overall mortality. (2) Methods: We conducted a 5-year prospective study including 161 patients on maintenance HD therapy. At baseline, we collected data related to VA history, comorbidities, demographics, subjective global assessment scale (SGA), and biochemical parameters. All patients underwent a complete AVF ultrasound and we recorded AVF blood flow and the presence of AVF calcifications, stenoses, and aneurysms. (3) Results: In our study, we found an AVF calcification prevalence of 39%. In a univariate analysis, we found that patients with AVF calcifications were associated with other AVF complications as well (stenoses, aneurysms), had longer AVF and HD vintage, as well as higher serum calcium and PTH values. In a multivariate analysis, we found that patients with a longer HD vintage and higher calcium values were independently associated with AVF calcifications. AVF calcifications did not affect 5-year fistula patency, nor were they associated with a higher mortality risk in our group of patients. (4) Conclusions: AVF calcifications were a frequent finding in our analysis, but their presence does not seem to affect the 5-year AVF patency.

Short and long-term effects of kidney donation on mineral and bone metabolism

BackgroundLiving kidney donors (LKD) experience an abrupt decline in glomerular filtration rate (GFR) resulting in abnormalities of mineral and bone metabolism (MBD), and this may have implications for skeletal health. We prospectively studied acute and long term MBD adaptation of LKD from two kidney transplant centers (São Paulo, Brazil and Miami, USA).MethodsRenal function and MBD parameters longitudinally after kidney donation (baseline – D0, day 1, 14, 180 and 360 post-operatively) were measured in 74 patients (40 y, 73% female, 54% Brazilian). A subset of 20 donors from Brazil were reassessed after 10 years of nephrectomy.ResultsAt baseline, Brazilian donors presented lower intact FGF23 (20.8 vs. 80.1 pg/mL, P < 0.01) and higher PTH (47.4 vs. 40.1, P = 0.04) than their US counterparts. GFR decreased to 63% of its baseline levels just after donation but improved 10% during the first year. PTH levels increased on D1, returning to baseline levels on D14, while FGF23 remained higher than baseline over the first year. LKD had a significant reduction of serum phosphate on D1, which returned to baseline levels on D180. A higher fractional excretion of phosphate (FEP) was noted since D14. After 10 years of donation, 20 LKD presented a sustained reduction in GFR (74.8 ± 14mL/min). There was a return to baseline in serum FGF23 [21.8 (18–30) pg/mL] and FEP, accompanied by an increase in serum calcium. PTH remained elevated (57.9 ± 18 pg/mL), whereas serum calcitriol and Klotho were lower than before the donation.ConclusionsThe abrupt decline in kidney mass is associated with an increase in PTH and FGF23 that is not explained by phosphate retention. In a long-term evaluation, LKD showed a sustained drop in GFR, with lower serum calcitriol and Klotho, and higher PTH. The effects of these changes should be investigated in further studies.

Effect of coated calcium feeding on growth performance, carcass traits, immunity, blood biochemistry and tibial bone morphometry in commercial broiler chicken.

The bone abnormalities pose great concern in heavy, rapidly growing broilers, resulting in significant economic loss, and health issues in birds. To address these problems and prevent unnecessary mineral excretion into environment, it is crucial to optimise the inclusion level of dietary calcium in broiler's diet. The calcium utilisation by the bird is also affected by its source, particle size, bioavailability etc. Hence this study aimed to study the effect of partially replacing conventional dietary calcium source with coated calcium on growth performance, immune response, carcass traits, blood calcium and phosphorus, and mineral retention in broilers. About 416 broiler chicks were randomly distributed into four treatments, each with eight replicates of 13 birds and fed with iso-calcium, isocaloric, and isonitrogenous diet for 42 days. The T0 (control) was a basal diet while the T1, T2, and T3, were treatment diets in which conventional calcium source (limestone) was partially replaced with coated calcium by 10, 20, and 30% respectively. The birds of T3 group showed higher (P < 0.05) body weight gain, better feed conversion ratio and higher carcass yields compared to T0, T1, and T2 diet fed birds. Further the treatment groups exhibited higher (P < 0.05) cell-mediated and humoral immune responses and immune organ weights compared to control. The tibial bone weight, length and average diameter was highest (P < 0.05) in T3. Moreover, the T3 diet fed group also showed higher (P < 0.05) calcium and phosphorus content in serum and bone and lowest content of these minerals in the excreta followed by T2, T1 and control. These findings suggest that a 30% conventional calcium source with coated calcium may be used as a high-grade mineral source for broiler chicken feed.

The regulation role of calcium channels in mammalian sperm function: a narrative review with a focus on humans and mice.

Mammalian sperm are characterized as specialized cells, as their transcriptional and translational processes are largely inactive. Emerging researches indicate that Ca2+ serves as a crucial second messenger in the modulation of various sperm physiological processes, such as capacitation, hyperactivation, and the acrosome reaction. Specifically, sperm-specific calcium channels, including CatSper, voltage-gated calcium channels (VGCCs), store-operated calcium channels (SOCCs), and cyclic nucleotide-gated (CNG) channels, are implicated in the regulation of calcium signaling in mammalian sperm. Calcium stores located in the sperm acrosomes, along with the IP3 receptors in the neck of the redundant nuclear envelope and the mitochondria in the tail, play significant roles in modulating intracellular Ca2+ levels in sperm. However, the functions and mechanisms of these calcium channels in modulating mammalian sperm physiological functions have not yet been well elucidated. Therefore, by focusing on humans and mice, this study aims to provide a comprehensive review of the current advancements in research regarding the roles of calcium signaling and associated calcium channels in regulating sperm function. This endeavor seeks to enhance the understanding of calcium signaling in sperm regulation and to facilitate the development of drugs for the treatment of infertility or as non-hormonal male contraceptives.

METABOLIC ALKALEMIA IN HYPERCALCIURIA STONE FORMERS: DOES IT MATTER?

We collected clinical, demographic characteristics, and laboratory data from electronical medical charts of outpatients with calcium-kidney stones followed in our institution from January 2013 to July 2021. We diagnosed as metabolic alkalemia those cases in which the venous blood gas tests showed pH≥7.46 and bicarbonate concentration&gt;26 mEq/L. Then, we applied statistical analysis to compare distinct categories between patients with and without metabolic alkalemia. We diagnosed metabolic alkalemia in 4.3% of hypercalciuric nephrolithiasis outpatients, and we verified that thiazides had been used in all of them except in one case. Furthermore, we observed that the amount of thiazide taken daily was higher in patients with metabolic alkalemia than those without this imbalance. Additionally, hypokalemia was present in 37% of patients that developed metabolic alkalemia. We also found lower chloride, magnesium and ionic calcium serum concentrations in patients with metabolic alkalemia than in those without an acid-base disequilibrium. Despite the low prevalence of metabolic alkalemia in hypercalciuric kidney stone formers, it is important to monitor these patients due to high incidence of hypokalemia and the potential presence of other electrolyte disorders.

Osteoporosis and Normocalcemic Primary Hyperparathyroidism (Conservatively or Surgically Managed)

Asymptomatic primary hyperparathyroidism (PHPT) involves 80–90% of the parathyroid tumor-associated cases of PHPT in the modern medical era, while normocalcemic PHPT (NPHPT) has a prevalence of 0.1–11%. We aimed to analyze the bone status and mineral metabolism in NPHPT amid conservative or surgical management. In this narrative review, we searched PubMed (between January 2020 and July 2024) via different keywords. Fourteen studies from the final analysis (388 patients with NPHPT; 1188 with PHPT; and 803 controls) showed that mean serum calcium levels varied between 2.57 and 2.26 mmol/L in NPHPT. Ten studies identified a similar 24 h urinary calcium in NPHPT versus hypercalcemic PHPT (HPHPT). Except for one study, a mandatory vitamin D analysis was performed, but the 25-hydroxyvitamin D cut-offs varied. Osteoporosis (n = 6 studies; N = 172 with NPHPT) was confirmed in 41.7–100% of NPHPT subjects. In surgery candidates, this rate might be overestimated. A DXA analysis was performed in eight studies (235 subjects with NPHPT, and 455 patients with HPHPT); two studies identified a lower BMD in HPHPT &lt; NPHPT, but the results were not homogenous. A single study analyzed the TBS and found similar results in NPHPT. The prevalence of fractures (n = 9) varied between 7.4% and 42.8% in NPHPT. Bone turnover markers (N = 262 patients, n = 8 studies) showed lower bone formation markers in NPHPT versus PHPT (n = 3). Two studies analyzed the BMD and bone turnover markers following parathyroidectomy (161 patients, including 30 patients with NPHPT; mean ages over 60 years). To conclude, given the wide spectrum of complications associated with PHPT, an early diagnosis and proper management is essential. A more extensive screening in patients with osteoporosis and kidney stones might lead to the discovery of NPHPT, a more recently described form of PHPT. While it is still unclear whether NPHPT is an early stage of HPHPT or a separate entity, recent findings show similar osteoporosis and fracture occurrence, and an improvement in bone metabolism, following parathyroidectomy. More extensive prospective studies are crucial to understand the natural course of the disease, to reach a consensus regarding parathyroidectomy indications and surgery candidates’ selection, and to ensure proper personalized management for these patients. With the evolving diagnosis methods, PHPT has become a condition with a changing clinical presentation, which now requires modern evaluation and treatment approaches.

The Pathology and Blood Biochemistry of Juvenile Lates calcarifer on Diets Contaminated With Mycotoxins, Histamines and Rancid Fats-A Case Study.

Mycotoxins, originating from contaminated raw materials or suboptimal feed storage, are a growing concern in tropical aquaculture. Common fungi such as Aspergillus spp. and Fusarium spp. produce mycotoxins including aflatoxin, fumonisin, deoxynivalenol and zearalenone. High doses or prolonged exposure (weeks) to low doses of these mycotoxins (< 20 μg/kg) can depress growth, immunity, and cause mortality. This study investigated poor growth and low survival in juvenile Asian seabass, Lates calcarifer fed two different diets (FM40 and ABS3) for 5 weeks. Analysis of these diets revealed high peroxide values, multiple mycotoxins and high histamine levels. Fish fed the FM40 diet, which was contaminated with aflatoxin B1 (13.2 μg/kg), aflatoxin B2 (1.9 μg/kg), deoxynivalenol (29.5 μg/kg), alternariol (2.2 μg/kg), elevated peroxide value (45.91 mEq/kg), and histamine (129.51 mg/kg) developed mild bile duct hyperplasia, depressed total serum proteins (50.40 ± 10.06 g/L), markedly elevated blood potassium (8.2 ± 0.18 mmol/L), and heavy iron deposits in splenic melanomacrophage centres (Perl's stain) indicative of increased haemolysis. The presence of multiple cytotoxic mycotoxins in FM40 diet could explain the increased haemolysis and elevated blood potassium. In contrast, fish fed the ABS3 diet, which had high histamine levels (210.05 mg/kg), exhibited protein-losing nephropathy with multifocal fibrin plugs (Martius scarlet blue stain) indicating acute renal damage, and elevated blood calcium and phosphorus levels. Histamine is metabolised and excreted through the kidneys and known to induce renal arteriolar constriction, disrupt glomerular filtration barrier and increase permeability resulting in protein loss. This study shows that blood biochemistry and histopathology are useful diagnostic tools for assessing the impact of mycotoxins and histamines on fish health.

Frequency and characteristics of ectopic parathyroid adenomas in a cohort of patients referred for 18F-fluorocholine PET/CT.

This article aimed to study the frequency and characteristics of ectopic/intrathyroidal parathyroid adenomas in patients referred for 18F-fluorocholine PET/computed tomography (CT). From 11 June 2015 to 15 January 2024, 729 patients were studied. Recorded patient variables included hyperparathyroidism type, sex, age, presence of symptoms, renal involvement, bone involvement, parathyroid hormone (PTH), and serum calcium, phosphate, and vitamin D as well as 24-h urine calcium excretion. PET/CT results were also collected. In case of parathyroidectomy, the weight of the adenomas was recorded. Continuous variables were expressed as mean ± SD. Differences were evaluated with Mann-Whitney U-tests or two-sample t-tests, when appropriate. P-values ≤0.05 were considered statistically significant. PET/CT showed no adenoma in 163 (22%), adenoma in 451 (62%), hyperplasia/multiglandular disease in 32 (4%), and equivocal results in 83 (11%) patients. A total of 6/729 (1%) adenomas were located intrathyroidally and 16/729 (2%) had an ectopic location. Patients with ectopic/intrathyroidal adenoma showed significantly higher serum PTH levels than patients with no visualization of adenoma on PET. The mean mass of the adenoma was 1 ± 2.3 g in patients with orthotopic adenomas versus 2.7 ± 3.3 g in patients with ectopic/intrathyroidal adenomas; however, this was not significantly different (P = 0.09). In the presented cohort, the frequency of ectopic/intrathyroidal parathyroid adenomas was 3%. No significant difference in weight was found between orthotopic and ectopic/intrathyroidal parathyroid adenomas.

Serum calcium relative decline as a predictor of post thyroidectomy hypocalcemia.

Serum calcium relative decline as a predictor of post thyroidectomy hypocalcemia.

Serum Lipid Profile and Electrolytes Reference Intervals for Apparently Healthy Children and Adolescents in Addis Ababa, Ethiopia.

Accurate reference intervals generated from an apparently healthy population and stratified by crucial variables such as age and gender are required to guarantee appropriate interpretation of test results. Since there were no local reference intervals in the study area, the present study aimed to establish reference intervals on serum lipid profiles and electrolytes for children and adolescents in Addis Ababa. This community-based cross-sectional study was conducted from April to October 2019. Laboratory analysis was performed using the automatic biochemical analyzer Cobas 6000 (c501) from Roche. According to Clinical and Laboratory Standards Institute (CLSI) guidelines, reference intervals for lipid profile and electrolyte tests for apparently healthy children and adolescents were established. We used a non-parametric method to calculate the 2.5th and 97.5th percentiles with a 90% confidence interval. In children, the reference intervals for serum potassium, sodium, chloride, calcium, magnesium, and phosphate in mmol/L were 4.37-5.20, 137-145.50, 101.90-107.90, 2.34-2.70, 0.74-0.97, and 1.42-1.85, respectively; and for total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein, the respective values were 100.76-171.70, 44.16-126.36, 60.60-105.60, and 31.60-53.70 in mg/dL, for both genders. For adolescents, the reference intervals were 4.03-5.58, 137-146, 98.90-120.90, 2.39-2.70, 0.73-0.96, and 0.96-1.80 for serum potassium, sodium, chloride, calcium, magnesium, and phosphate in mmol/L, respectively; and 97.20-189.10, 40.50-143.60, 41.70-120.90, and 21.30-57.0 in mg/dL for total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein, respectively, for both genders. The established reference intervals in the current study revealed that both the lower and upper limits contradicted the manufacturer values as well as the available literature. The study also discovered significant gender differences in reference values for TC, TG, LDL-C, potassium, phosphate, and chloride in the adolescent age groups.

Seasonal dynamics of indicators of mineral metabolism in horses in the conditions of the Leningrad region

The article analyzes the seasonal dynamics of mineral metabolism indicators in adult horses kept in private stables in the Leningrad region. As a result of the research, knowledge of the concentration and dependence of indicators on the seasonality of the year was obtained. It is important to remember that macro- and microelements are not synthesized in the body, they come from food, water, and air. The degree of their assimilation depends on the state of the respiratory and digestive organs. The most difficult period for animals is winter, when there is a decrease in the resistance of the body as a whole due to poor climatic conditions and minimizing physical activity in the fresh air. All these are predisposing factors for the imbalance of indicators at the level of the whole organism.It is established that in the autumn-winter period there is a decrease in indicators relative to the average annual digital values. Thus, there is a linear relationship between the concentration of calcium and phosphorus in blood serum – the minimum values are observed in winter and are 2.53±0.27 mmol/l and 1.76± 0.11 mmol/l, respectively. And the maximum values are typical for the autumn period and are 3.63±0.29 mmol/l for calcium and 2.33±0.12 mmol/l for phosphorus. Similar dynamics is observed in other indicators of the body's mineral metabolism. Thus, for trace elements such as copper, iron, protein-bound iodine, the minimum values were noted in the spring period. This can be explained by a decrease in the mineral components of the feed itself, as a result of long-term storage, resulting in changes in the chemical composition of vegetable feed with fat oxidation. Microelementoses and osteodystrophic processes are observed in animals. The autumn period is characterized by the highest concentrations of minerals in the blood serum of horses, on average by 8-12% compared with the average annual figures, This is explained by the fact that it was in the summer period that the greatest benefit was obtained from juicy plant substances of feed and proper exercise.This knowledge is necessary to understand the processes occurring in the body of horses at different times of the year and the possibility of correcting mineral supplements based on the data obtained

Variation in blood glucose, cholesterol, urea and calcium levels according to the physiological stage in Ouled-Djellal ewes in Algerian arid zone. Technical note

Sheep farming in arid and semi-arid regions of Algeria is confronted with large fluctuations in the availability of fodder, which is all the more restrictive for pregnant ewes whose needs are at a maximum and constitute a major obstacle to the development of this sector. This study aims to evaluate the influence of the physiological stage on the energy, nitrogen and mineral status of Ouled-Djellal ewes living in arid zones (Biskra), by determining the plasma levels of glucose, cholesterol, urea and calcium. Blood samples were taken from 40 ewes divided into two groups according to their physiological stage (pregnant and empty). The obtained results showed that the physiological stage had a significant influence only on blood glucose, being higher in empty sheep than in pregnant sheep (P&lt;0.05), whereas for the other blood parameters: cholesterol, urea, and the plasma concentrations of calcium do not seem to be influenced by the physiological stage.

The polar vessel sign: insights from CT imaging analysis in Asian Indian primary hyperparathyroidism.

Data on the polar vessel sign (enlarged feeding vessel terminating in parathyroid lesions) on four-dimensional computed tomography (4D-CT) is limited. We performed a retrospective analysis to determine the prevalence, predictors, and adjunctive utility of polar vessel sign in pre-operative 4D-CT of patients with primary hyperparathyroidism (PHPT). One radiologist blinded to the patients' details reported the 4D-CT of eighty-four operated patients with histopathology-proven single-gland PHPT. Two protocols were used to obtain arterial-phase images: timed via bolus tracking (n = 41) or fixed at 20 s after contrast injection (n = 43). Seventy-one patients were symptomatic for PHPT, with median serum calcium 12.1 mg/dL. On the arterial phase of 4D-CT, 88.1% of lesions had the polar vessel sign, including 7/9 asymptomatic patients, 6/6 parathyroid carcinomas, and 3/4 ectopic(1:mediastinum, 2:thyro-thymic ligament). Predictors of polar vessel sign were maximum lesion dimension (2.2 vs. 1.4 cm; P = 0.03), solid-cystic CT morphology (47.3% vs. none; P = 0.004), and bolus tracking-timed arterial phase (55.4% vs. none; P = 0.001). Of these, bolus tracking improved the polar vessel's visualization (100% vs. 76.7%; P = 0.001) independent of lesion dimension and solid-cystic morphology. The latter two predicted polar vessel sign in images obtained at a fixed interval (20 s). A significantly lower proportion of bolus tracking-timed scans had lesion percentage arterial enhancement (PAE) < 128.9% (2/41 vs. 9/43; P = 0.04). Even with suboptimal PAE, the polar vessel helped identify 9/11 lesions. The polar vessel sign demonstrated an additive role to PAE during CT reporting. Bolus tracking is valuable in optimizing vessel and tumor arterial enhancement and is easily incorporated into parathyroid 4D-CT protocol.

Association between serum calcium and in-hospital mortality in intensive care unit patients with cerebral infarction: a cohort study

BackgroundThe relationship between serum calcium levels and the prognosis of cerebral infarction remains controversial.PurposeThis study aims to investigate the correlation between serum calcium levels and in-hospital mortality in critically ill patients with ischemic stroke admitted to the intensive care unit (ICU).MethodsA retrospective cohort study was conducted using data from the MIMIC-IV database. Demographic and clinical data of all participants were collected including gender, age, hypertension, diabetes, myocardial infarction, heart failure, chronic obstructive pulmonary disease, hemoglobin, potassium, sodium, anion gap, platelets, white blood cells, glucose, creatinine, Glasgow coma score (GCS), IV-tPA administration (rt-PA), and mechanical thrombectomy (MT). The outcome measure was in-hospital death. Multivariable-adjusted logistic regression analysis, curve fitting, interaction analysis, and threshold effect analysis were employed to evaluate the relationship between serum calcium levels and in-hospital mortality among ICU patients with cerebral infarction.ResultsA total of 2,680 critically ill patients with cerebral infarction were enrolled, with a mean serum calcium level of 8.6 ± 0.8 mg/dL. The overall in-hospital mortality rate was 19.5%, where Group 1 (serum calcium &amp;lt; 8.0 mg/dL) had a mortality rate of 27.7%, Group 2 (serum calcium 8–9 mg/dL) had a rate of 19.8%, and Group 3 (serum calcium ≥ 9 mg/dL) had a rate of 13.9%. There was a non-linear, S-shaped relationship between serum calcium levels and in-hospital mortality. Serum calcium levels within the range of 7.70–9.50 mg/dL were found to be independently associated with increased in-hospital mortality in ICU patients with cerebral infarction. No significant interactions were detected in subgroup analyses, and the results of sensitivity analyses remained stable.ConclusionSerum calcium levels are independently associated with in-hospital mortality in critically ill patients with cerebral infarction in the ICU setting. Within the range of 7.70–9.50 mg/dL, lower serum calcium levels increase the risk of in-hospital death among these patients, emphasizing the importance of close monitoring by ICU physicians.

Incidental Parathyroidectomy After Thyroid Surgery: A Single-Center Study.

Hypoparathyroidism with hypocalcemia is the most frequent complication after thyroid surgery. Many risk factors have been involved in the development of this complication, with conflicting results. Incidental parathyroidectomy (IP) may be a frequent cause of postoperative hypocalcemia. In this study, we have evaluated the risk factors associated with the IP in a single-center cohort of patients undergoing thyroid surgery. The incidence and the risk factors for IP were evaluated in 799 patients scheduled for surgical treatment for thyroid disease between January 2018 and December 2023. Parathyroid hormone levels and serum calcium levels, together with the histological specimens, were evaluated in all patients. Post-operative temporary hypocalcemia was present in 239 (29.9%) patients. A total of 144 patients (21.9%) had an incidental parathyroidectomy. Younger patients (<40 years) had the highest risk of having an incidental parathyroidectomy (RR 1.53 (95% CI 1.084-2.161), OR 1.72 (95% CI 1.091-2.710), p = 0.014). Moreover, thyroid cancer (RR 1.4 (95 CI 1.114-1.882) OR 1.68 (95% CI 1.145-2.484), p < 0.05) and the neck dissection (RR 1.75 (95% CI 1.409-2.198) OR 2.38 (95% CI 1.644-3.460), p < 0.001) were strongly associated with the risk of incidental parathyroidectomy. Younger female patients with thyroid cancer and neck dissection were at the highest risk of incidental parathyroidectomy. A meticulous surgical dissection, together with imaging methods for the detection of the parathyroid glands, may reduce the incidence of this complication.

Serum biochemical evaluation of healing of critical-sized long bone defects in rats treated with biphasic hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) bioceramic scaffolds

Critical-sized long bone defects are those that would not heal spontaneously despite surgical stabilisation. The use of bioceramic scaffold has shown promising results in the repair of bone defects. The present study was undertaken to evaluate the serum biochemical parameters of Wistar rats treated for critical-sized segmental bone loss using biphasic hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) bioceramic scaffolds. The study was conducted in eighty male Wistar rats aged between 8-12 weeks, weighing 200-250 g body weight with critical-sized segmental defects in the femur. A 6 mm segmental mid-diaphyseal femoral defect was created under general anaesthesia. The bone defect was bridged with bioceramic scaffolds and retained in position with microplate and screws. Serum biochemical parameters serum calcium, phosphorous, acid phosphatase and alkaline phosphatase were evaluated four weeks before surgery, immediately after surgery and 4th, 8th, 12th, and 16th week after surgery. The evaluation of both serum calcium and phosphorous were found to be reliable indicators of new bone formation and mineralisation, whereas the evaluation of both serum acid phosphatase and alkaline phosphatase were found to be reliable indicators of bone healing during the treatment of critical-sized long bone defects in rats using biphasic hydroxyapatite and β-tricalcium phosphate bioceramic scaffolds Keywords: Beta-tricalcium phosphate, bioceramic scaffold, hydroxyapatite, serum acid phosphatase, serum alkaline phosphatase, serum calcium, serum phosphorous

Delving into diversity: exploring different risk factors of premature greying of hair

Dear Madam, Hair is said to grey prematurely when a minimum of five grey hairs occur before the age of 20 in Caucasians, 25 in Asians and 30 in Africans1. Some authors propose using 25 years as a cut-off for people in the South Asian subcontinent. Also, there's no universal grading system for premature greying of hair (PGH). This letter addresses the various evolving risk factors for PGH in young adults worldwide. PGH may be familial or genetically influenced, traveling in an Autosomal Dominant pattern. A positive family history, in particular the paternal history is the most powerful risk factor2. PGH is also linked to nutritional deficiencies including vitamins (especially B12) and minerals. For example in one study, significantly lower levels of serum calcium, ferritin, vitamin B12, and high HDL were observed in patients3. T3 and T4 act on hair follicles to cause melanogenesis and their deficiency is therefore associated with PGH, alopecia, and changes in hair morphology. Another study found notably reduced levels of copper in cases (PGH) as compared to the control group. This study, however, did not observe lower levels of zinc or iron among the affected population. A separate case-control study concerning the association of epidemiological and biochemical factors with PGH reported that a significantly higher percentage of individuals with premature greying had atopic diathesis, led sedentary lifestyles, had family histories of the condition, smoked, and had reported higher levels of perceived stress compared to controls. Though, interestingly enough, regular application of hair oil seemed to confer a safeguarding effect against premature greying. Upon further review of the literature, it became apparent that both BMI and exposure to sunlight emerged as substantial predictors of PGH. Despite the prescription of various vitamins and minerals like biotin, calcium pantothenate, zinc, copper, and selenium (all of which have been recognized as risk factors), the outcomes have been disappointing. Calcium pantothenate is frequently recommended for premature greying of hair (PGH)4. This highlights an existing knowledge gap concerning the precise causative risk factors, necessitating further investigation for a comprehensive understanding and improved management of individuals experiencing premature greying of hair.

Study of Association of PPH due to Uterine Atonicity and Serum Calcium levels

Background: Uterine atonicity stands out as a primary and leading factor contributing to maternal morbidity and mortality. Postpartum hemorrhage (PPH) resulting from uterine atony poses a life-threatening risk. Oxytocic drugs, by elevating intracellular calcium, enhance uterine tonicity, with optimal calcium levels playing a crucial role in facilitating effective uterine contractions. The study aimed to explore the relationship between the concentration of calcium in the bloodstream and the occurrence of PPH associated with inadequate uterine contractions admitted during the 1st and 2nd stages of labour at a tertiary care facility such as the Combined Military Hospital in Dhaka. The study likely involved analyzing data to identify any patterns or connections between serum calcium levels and the incidence of uterine atony-related PPH. Methods: The study follows a randomizing controlled trial (RCT) design within the Department of Obstetrics and Gynecology at Combined Military Hospital, Dhaka. The study duration spans from January 2016 to January 2019, involving a total of 306 subjects. Group A includes those with serum calcium levels between 8-10.4 mg/dl without uterine atonicity, while Group B comprises individuals with serum calcium levels below 8 mg/dl experiencing uterine atonicity, either post cesarean or vaginal delivery. Atonicity features include a soft, distended uterus with a lack of muscle tone. Results: A total of 306 patients were included in the study, with 153 having serum calcium levels exceeding 8 mg/dl and another 153 having levels below 8 mg/dl. Among women with serum calcium levels below 8 mg/dl, 37 patients experienced uterine atonicity. In contrast, it was observed that among women with serum calcium levels exceeding 8 mg/dl, only one patient experienced uterine atonicity. This highlights a potential association between higher serum calcium levels and a reduced likelihood of developing uterine atony in the studied population. Conclusions: The study findings indicate a strong association between low calcium levels and reduced uterine tonicity, establishing low calcium as a significant risk factor for uterine atony. Bangladesh Armed Forces Med J Vol 57 No (1) June 2024, pp 28-34