Excellent choice! The urine sediment can often provide clues to the etiology of a patient’s kidney disease.

Great!  The urine protein to  urine creatinine ratio is 10, which tells us that this patient is excreting approximate 10 grams of protein in the urine over 24 hours (nephrotic range proteinuria!). Though the urinalysis gives us an estimate of the degree of albuminuria, proteinuria should be quantified when present.  Further, the urinalysis does NOT detect non-albumin proteins, like immunoglobulins which may be present in the urine in other disease states. Of note, this test is most accurate when the patient’s serum creatinine is at steady state (or not changing day to day).

This might be a low yield test here, given the urinalysis findings. Complement levels should be investigated in patients with signs and symptoms suggestive of nephritic syndrome. Try again!

This is a low yield test here. Traditionally, this test has been described for acute interstitial nephritis (AIN) – though the sensitivity and specificity for AIN is also poor. Pick again!

The CPK can be markedly elevated in patients with rhabdomyolysis, or breakdown of muscle that can subsequently lead to acute kidney injury. Classically, the urine of these patients is positive for “blood” on the urine dipstick, without the presence of red blood cells – here, the dipstick is negative for blood. Try another test!

Though diabetic nephropathy (DN) often presents with albuminuria, it would be unusual for a young patient to develop sudden onset of nephrotic syndrome due to DN. Diabetic nephropathy more commonly presents after the disease has been present for several years, thus this kidney disease would be less likely in a 7 year old without known history of diabetes. Let’s try again!