Interpretation of Parathyroid Hormone Levels in Renal Impairment

Abstract

Distinguishing between acute kidney injury and chronic kidney disease (CKD) in an emergency setting may pose a conundrum for physicians, especially when a patient’s medical history and records are unknown. Parathyroid hormone (PTH) has proved valuable as a marker of CKD and is frequently assayed for this reason. The use of PTH as a sole marker of CKD may be misleading in certain conditions, and for this reason, physicians need to interpret PTH values with caution. In patients with no existing medical records, it is vital to consider their overall clinical picture, an accurate interpretation of urinalysis and urine microscopy, and the PTH values when making the initial management decisions.

Secondary hyperparathyroidism: Update

“…At the renal level, PTH acts on the ascending limb of the loop of Henle and the distal convoluted tubule, where it increases calcium reabsorption, inhibits phosphate reabsorption, and increases phosphate excretion. Additionally, PTH promotes the conversion of 25-hydroxyvitamin D into its active metabolite calcitriol (1,25[OH]2D) by activating 1αhydroxylase. Calcitriol enhances calcium absorption from food in the small intestine [7].…”

“…These values should always be interpreted in the appropriate clinical context and associated with serum calcium and phosphate levels. In patients with CKD, higher PTH levels are needed to maintain adequate bone function, which can reach up to 4 times the upper limit of normal (125-250 pg/ml) in patients on renal replacement therapy [25].…”

Parathyroid disease; a bridge between nephrologist and endocrinologist

“…Elevated levels of PTH and calcium, characteristic of hyperparathyroidism, can lead to the deposition of calcium in the kidneys, causing kidney stones and impaired kidney function. Nephrologists play a vital role in assessing and monitoring kidney function in patients with parathyroid disease (19,20).…”

“…This collaboration is essential in optimizing treatment plans, managing complications, and improving longterm outcomes. Here are some specific aspects of their collaboration (19,27).…”

Effect of niacin on phosphorus, calcium, parathormone and vitamin D levels in hemodialysis patients; a double-blinded randomized clinical trial

“…As the glomerular filtration rate decreases, the kidney's ability to regulate electrolytes decreases. Therefore, electrolyte disorders such as hyperphosphatemia (subsequently an increase in the serum level of parathyroid hormone), hypocalcemia, and reduction of serum vitamin D in hemodialysis patients can be occurred (5,6). Although some drugs have…”