Certified Nephrology Nurse Certification (CNN) Practice Exam 2025 – Comprehensive All-in-One Study Guide for Exam Success!

In patients with Polycystic Kidney Disease (PKD), the most common cause of pain is due to the expansion of cysts. As the cysts enlarge, which is characteristic of PKD, they can distend the renal capsule and cause significant discomfort or pain in the abdomen and flank areas. The growing cysts create pressure on surrounding tissues, leading to localized pain that is often described by patients as a deep, aching sensation.

While infections, inflammation, and kidney stones can also cause pain in renal patients, they are not as directly associated with the specific pathology of PKD as the expanding cysts. Infections may arise in the context of PKD, but they are not a frequent primary source of pain compared to the distension of the cysts. Similarly, inflammation may occur but is also not as characteristic of PKD as the symptom of pain caused by cyst growth. Although kidney stones can cause severe pain, they are a separate condition and not an inherent aspect of the PKD disease process itself. Thus, the expansion of cysts stands out as the predominant cause of pain in this patient population.