Severe hypercalcemia complicating recovery of acute kidney injury due to rhabdomyolysis

Two-way Road of Kidney and Hypercalcemia: A Narrative Review

Calcium homeostasis is regulated by the dyad of parathyroid hormone and calcitriol, whereas kidney, intestine, and bone are the primary target sites. Elevation of serum calcium levels and hypercalcemia are likely markers of pathological conditions, particularly malignancy and hyperparathyroidism. Similarly, several dysfunctions within the body can direct hypercalcemia. Furthermore, chemicals and drugs can also drive this condition. Owing to the significant role of the kidney in calcium homeostasis, renal abnormalities lead to hypercalcemia and increased calcium levels can have pathological effects on the kidney. This review is designed to highlight some of the commonly known causes of hypercalcemia and their effects on the kidney.

Trauma-related electrolyte disturbances: From resuscitation to rhabdomyolysis

Traumatic injury results in drastic changes to a patient's normal physiology. The hormonal stress response, as well as some treatment strategies, lead to significant disruptions in electrolyte homeostasis that are important for clinicians to understand. In addition, advances in fluid resuscitation and modern transfusion practices have led to their own unique set of consequences, which we are just beginning to appreciate. Special attention is placed on rhabdomyolysis, as this distinct entity represents an extreme example of injury induced electrolyte derangements. This review describes the physiologic response to trauma and highlights some of the important electrolyte abnormalities that can be encountered while caring for the injured patient.

Rare Causes of Hypercalcemia: 2021 Update

CONTEXT

Primary hyperparathyroidism and malignancy are the etiologies in 90% of cases of hypercalcemia. When these entities are not the etiology of hypercalcemia, uncommon conditions need to be considered. In 2005, Jacobs and Bilezikian published a clinical review of rare causes of hypercalcemia, focusing on mechanisms and pathophysiology. This review is an updated synopsis of rare causes of hypercalcemia, extending the observations of the original article.

EVIDENCE ACQUISITION

Articles reporting rare associations between hypercalcemia and unusual conditions were identified through a comprehensive extensive PubMed-based search using the search terms "hypercalcemia" and "etiology," as well as examining the references in the identified case reports. We categorized the reports by adults vs pediatric and further categorized the adult reports based on etiology. Some included reports lacked definitive assessment of etiology and are reported as unknown mechanism with discussion of likely etiology.

EVIDENCE SYNTHESIS

There is a growing understanding of the breadth of unusual causes of hypercalcemia. When the cause of hypercalcemia is elusive, a focus on mechanism and review of prior reported cases is key to successful determination of the etiology.

CONCLUSIONS

The ever-expanding reports of patients with rare and even unknown mechanisms of hypercalcemia illustrate the need for continued investigation into the complexities of human calcium metabolism.

Rhabdomyolysis and severe biphasic disturbance of calcium homeostasis secondary to COVID-19 infection

We report a case of severe hypercalcaemia secondary to rhabdomyolysis in a woman with COVID-19 (SARS CoV-2) infection. The patient presented with myalgia and anuria with an acute kidney injury requiring haemodialysis. Creatine kinase peaked at 760 000 IU/L. A biphasic calcaemic response was observed with initial severe hypocalcaemia followed by severe, symptomatic hypercalcaemia, persistent despite haemodialysis. Control of the calcium levels was achieved by continuous haemofiltration.

Impact of Acute Kidney Injury on Outcomes of Hospitalizations for Heat Stroke in the United States

This study aims to evaluate the risk factors and the association of acute kidney injury with treatments, complications, outcomes, and resource utilization in patients hospitalized for heat stroke in the United States. Hospitalized patients from years 2003 to 2014 with a primary diagnosis of heat stroke were identified in the National Inpatient Sample dataset. End stage kidney disease patients were excluded. The occurrence of acute kidney injury during hospitalization was identified using the hospital diagnosis code. The associations between acute kidney injury and clinical characteristics, in-hospital treatments, outcomes, and resource utilization were assessed using multivariable analyses. A total of 3346 hospital admissions were included in the analysis. Acute kidney injury occurred in 1206 (36%) admissions, of which 49 (1.5%) required dialysis. The risk factors for acute kidney injury included age 20–39 years, African American race, obesity, chronic kidney disease, congestive heart failure, and rhabdomyolysis, whereas age <20 or ≥60 years were associated with lower risk of acute kidney injury. The need for mechanical ventilation and blood transfusion was higher when acute kidney injury occurred. Acute kidney injury was associated with electrolyte and acid-base derangements, sepsis, acute myocardial infarction, ventricular arrhythmia or cardiac arrest, respiratory, circulatory, liver, neurological, hematological failure, and in-hospital mortality. Length of hospital stay and hospitalization cost were higher in acute kidney injury patients. Approximately one third of heat stroke patients developed acute kidney injury during hospitalization. Acute kidney injury was associated with several complications, and higher mortality and resource utilization.

Hypercalcemia: a consultant's approach

Due to their daily involvement in mineral metabolism, nephrologists are often asked to consult on children with hypercalcemia. This might become even more pertinent when the hypercalcemia is associated with acute kidney injury and/or hypercalciuria and renal calcifications. The best way to assess the severity of hypercalcemia is by measurement of plasma ionized calcium, and if not available by adjusting serum total calcium to albumin concentration. The differential diagnosis of the possible etiologies of the disturbance in the mineral homeostasis starts with the assessment of serum parathyroid hormone concentration, followed by that of vitamin D metabolites in search of both genetic and acquired etiologies. Several tools are available to acutely treat hypercalcemia with the current main components being fluids, loop diuretics, and antiresorptive agents. This review will address the pathophysiologic mechanisms, clinical manifestations, and treatment modalities involved in hypercalcemia.