Proteinuria

A 55-year-old female with diabetes mellitus presents for a routine clinic visit. She has been following the dietician’s recommendations and eating a low-carbohydrate diet and low-fat diet with a high content of lean protein, fiber, fruits, and vegetables. She has been walking to the park everyday, which takes about 45 minutes round trip. Her ophthalmologist has told her that she does not have retinopathy, and she has no foot ulcers. Her blood pressure measured at the local pharmacy has been around 145/95 mm Hg. Medications include insulin, hydrochlorothiazide, aspirin, and simvastatin. Physical examination reveals that she does not have distress; her blood pressure is 150/90 mm Hg, and she is obese.

Blood chemistry:

Sodium, 134 mmol/L

Potassium, 3.4 mmol/L

Chloride, 106 mmol/L

Total CO₂, 22 mmol/L

Urea nitrogen, 26 mg/dL (9.3 mmol/L)

Creatinine, 2.0 mg/dL (177 mcmol/L)

Glucose, 185 mg/dL (10.3 mmol/L)

Glycated hemoglobin, 8.2%

Complete blood count:

White blood cells, 4,200/mm³

Hemoglobin, 11.0 g/dL (110 g/L)

Hematocrit, 38%

Platelets, 299,000/mm³

Urinalysis:

Specific gravity, 1.025

pH, 5.5

Protein, 1+

Blood, 1+

Glucose, 2+

Ketones, negative

Bilirubin, negative

Urobilinogen, negative

Leukocyte esterase, negative

Nitrite, negative

WBC, 2/hpf

RBC, 0/hpf

Few granular casts

Microalbumin screen, ACR, 200 mg/g (22.6 mg/mmol)

Q: Which of the following interventions is not indicated?

1. Control diabetes

2. Control blood pressure

3. Add an ACE-inhibitor

4. Renal ultrasound

5. Protein restriction of 0.6 g per kg per day

A: First, we need to establish the etiology of the renal disease. The plasma creatinine is elevated, presumably indicating CKD (though a previous or follow-up level is needed to be certain). A renal ultrasound is indicated due to the presence of azotemia to evaluate renal anatomy and exclude obstruction. Microalbuminuria is urinary albumin excretion between 30 and 300 mg per day (or 30 to 300 mg per g creatinine (3.4–34 mg/mmol) or 20 to 200 μg per minute) and, if persistent, suggests the presence of glomerular disease. An ACR allows estimation of 24-hour albuminuria from a random sample of urine. This patient has 200 mg per g (22.6 mg/mmol), which is in the microalbuminuric range. It is imperative to bring the diabetes under control and control the blood pressure to prevent progression of CKD (see Chapters 12 and 13

Only gold members can continue reading. Log In or Register to continue