A clinician is reviewing laboratory results for four different patients being evaluated for mineral and bone disorders. Match each laboratory profile with its most likely underlying pathophysiologic diagnosis.
- Elevated serum calcium, decreased serum phosphorus, elevated intact parathyroid hormone (PTH), and increased urinary calcium excretion (>200 mg/day).Primary hyperparathyroidism
- Decreased serum calcium, increased serum phosphorus, decreased intact PTH, and normal BUN and creatinine.Primary hypoparathyroidism
- Decreased serum calcium, increased serum phosphorus, markedly elevated intact PTH, and increased BUN and creatinine.Secondary hyperparathyroidism due to chronic kidney disease
- Elevated serum calcium, low-normal serum phosphorus, normal to mildly elevated intact PTH, and low urinary calcium (urine calcium-to-creatinine clearance ratio < 0.01).Familial hypocalciuric hypercalcemia (FHH)
Cevap
Profile 1 matches Primary hyperparathyroidism; Profile 2 matches Primary hypoparathyroidism; Profile 3 matches Secondary hyperparathyroidism due to chronic kidney disease; Profile 4 matches Familial hypocalciuric hypercalcemia (FHH).
Each laboratory profile distinctly maps to a pathophysiologic state: Primary hyperparathyroidism is characterized by autonomous PTH excess leading to hypercalcemia and hypercalciuria. Primary hypoparathyroidism involves absent PTH causing hypocalcemia and hyperphosphatemia. Secondary hyperparathyroidism in CKD presents with hypocalcemia and hyperphosphatemia due to renal failure, which drives up PTH. FHH is a genetic CaSR mutation causing mild hypercalcemia with inappropriately normal/high PTH, uniquely identified by very low urinary calcium.
Adım Adım Çözüm
Anahtar Kavram
Differential diagnosis of calcium and parathyroid hormone disorders based on serum and urine biochemical markers.
Tahmini Süre:1m 30s