American Board of Surgery Qualifying Exam (ABS QE) Practice Test

What can be a common finding in chronic kidney transplant rejection?

1. Acute tubular necrosis

2. Chronic interstitial nephritis

3. Interstitial fibrosis and tubular atrophy

4. Chronic pyelonephritis

The correct answer is: Interstitial fibrosis and tubular atrophy

Chronic kidney transplant rejection is characterized by a progressive decline in kidney function and is often associated with specific histological findings. One of the hallmark features of this condition is interstitial fibrosis and tubular atrophy. In the setting of chronic rejection, the immune response can lead to chronic inflammation and damage to the renal interstitium. This results in the formation of fibrous tissue in the interstitial space, which can replace the normal kidney tissue. Alongside this, there is also atrophy of the renal tubules, contributing to a decrease in the functional capacity of the kidney over time. The combination of these processes leads to the classic picture of interstitial fibrosis and tubular atrophy observed in biopsies from kidney transplant recipients experiencing chronic rejection. Understanding this process is crucial because it provides insight into how chronic damage accumulates in transplanted kidneys, distinguishing it from other conditions like acute tubular necrosis, which is more related to acute injury or ischemia, or pyelonephritis, which typically results from infectious processes. Furthermore, chronic interstitial nephritis can be a broader category that may include various pathological insults but does not specifically delineate the mechanisms of rejection as clearly as interstitial fibrosis and tubular atrophy do.