13/06/2023
Hi vet ! do you know the differencials for hypocalcemia ?
Calcium serves two principal physiologic functions. First, insoluble calcium salts provide the structural characteristics that allow bones to protect internal organs and bear weight. Second, soluble calcium ions in the extracellular fluid (ECF) and cytosol are critically important for a myriad of biochemical intracellular and extracellular functions. For example, calcium is necessary for various enzymatic reactions, transport of substances across membranes and membrane stability, blood coagulation, nerve conduction, neuromuscular transmission, muscle contraction, smooth muscle tone, hormone secretion, bone formation, hepatic glycogen metabolism, cell growth, and cell division. Approximately 1% of total body calcium is contained within the ECF and soft tissue, 99% is found in bone.
The concentration of serum ionized calcium and the calcium content of skeleton is maintained within narrow limits by a complicated homeostatic system involving multiple organs (parathyroid glands, kidneys, skeleton, and gut) and several hormones (e.g., parathyroid hormone (PTH), vitamin D, and PTH-related protein (PTHrP)). The actions of PTH on bone resorption, renal calcium excretion, and metabolism of vitamin D are responsible for maintaining homeostasis. Abnormalities in any of these organs, hormones, or receptors may cause disturbances in calcium metabolism that can lead to hypercalcemia or hypocalcemia.
Hypocalcemia refers to a decrease in serum total and/or ionized calcium concentrations.
Reference intervals (for cats and dogs):
- total: 9.5-11.5 mg/dL (2.32-3.06 mmol/L)
- ionized: 1.2-1.4 mmol/L
It should be noted that clinically significant hypocalcaemia is generally not apparent until the total and ionized calcium decrease to