Question

A 68-year-old woman with heart failure presents with tachycardia, S3 heart sound and basilar crackles bilaterally. BP is 90/68 mmHg; BUN is 58 mg/dL (20.7 mmol/L); creatinine level is 2.4 mg/dL. This clinical presentation is most consistent with:

A. Prerenal azotemiaB. Acute glomerulonephritisC. Tubular necrosisD. Postrenal azotemia

Answer 1

A. Prerenal azotemia

Step-by-step explanation:

Prerenal azotemia can be seen as the way in which the blood that flows or circulates to the kidneys is not sufficient enough leading to decrease in blood flow to the kidneys.

Although this can occur due to some reasons such as hemorrhage, shock, congestive heart failure, adrenal insufficiency among others.

A damaged or injured kidney can also lead to PRERENAL AZOTEMIA because the kidneys can no longer get rid of enough nitrogen waste which may lead to

abnormally high level of nitrogen waste products in the blood causing the fluid not to flow enough to the kidneys which is why PRERENAL AZOTEMIA is the most common known cause of acute renal failure.

Based on the information given concerning the 68 years old woman the clinical presentation is most consistent with: PRENETAL AZOTEMIA.

Answer 2

A. Prerenal azotemia

Step-by-step explanation:

Prerenal azotemia is the most common type of acute renal failure. Prerenal azotemia is a condition where the kidneys are hypoperfused, this leads to acute tubular necrosis. This hypoperfusion is as a result of decreased circulating volume especially for patient with dehydration and blood loss, decreased cardiac output (seen in patients with heart failure) and excessive sequestering of fluids for patient with burns. For prerenal azotemia BUN:creatinine(cr) ratio > 20:1. In this case BUN is 58 mg/dL (20.7 mmol/L); creatinine level is 2.4 mg/dL, therefore BUN/cr = 58:2.4 = 24.17:1

Laboratoty findings for some disease are:

1. Acute glomerulonephritis: BUN:creatinine(cr) ratio > 20:1
2. Acute Tubular necrosis: BUN:creatinine(cr) ratio < 20:1