Correct! In a patient with hypercalcemia without evidence of volume overload, the first step is volume resuscitation with isotonic fluid. If the patient develops evidence of overload, loop diuretics can be given with intravenous fluids.

Oops! Try again, there’s a better initial step for this case.

Ouch! We still have some work to do before we might think about a kidney biopsy. Try again! 

We may reach for a bisphosphonate later, but there’s a better option for us to start with.

The mechanism of action of calcitonin may be of some benefit here, but this is not the best way to begin the management of this patient.

Correct! Checking the iPTH level is the first step to solving any case of hypercalcemia. The iPTH is undetectable. 

This is not the highest yield test here, as we don’t have any evidence of complement mediated disease so far. Try again!

Ouch! There are less invasive tests that are likely to provide more information about this patient’s hypercalcemia.

The urine sodium may be low in hypercalcemic patients due to vasoconstriction of the blood vessels and hypovolemia, but won’t help us differentiate between causes of hypercalcemia.

Pick again! Uric acid levels are less likely to help us figure out why this patient is hypercalcemic.

Pick again! Urine citrate levels may be helpful in a patient with nephrolithiasis, but probably won’t be of use here.

A V/Q scan may useful if there is clinical suspicion for a pulmonary embolism, but won’t help us narrow down a differential for hypercalcemia.

Great! A patient with hypercalcemia and acute kidney injury should raise suspicion for a monoclonal gammopathy. The SPEP reveals a monoclonal protein (“M” spike) and the IFE identifies it as an immunoglobulin G (IgG).

Good choice. Elevated PTH-rP levels might suggest humoral hypercalcemia. Here, it’s undetectable

Yes! Elevated calcitriol levels might narrow down our hypercalcemia differential diagnosis. Here, it’s slightly below the lower limit of normal (10 pg/mL)

Careful! A bronschoscopy is an invasive test that doesn’t seem to be indicated yet here. Choose again!