PKD is silent but stoppable -- if families don’t skip their checkups

On the surface, it appears perfectly normal, but within the kidneys, countless fluid-filled sacs (cysts) may grow quietly and destroy the organs.

This disease is called polycystic kidney disease (PKD). It is a relatively common genetic disorder that affects about one in 1,000 adults. It is estimated that about 30,000 to 40,000 patients live with this condition in Korea.

Professor Choi Soo-jeong

“PKD is a genetic disorder that causes numerous fluid-filled sacs to form inside the kidneys. This leads to the kidneys gradually enlarging while their function declines, resulting in chronic kidney disease,” said Professor Choi Soo-jeong of the Nephrology Department at Soon Chun Hyang University Hospital Bucheon. “Early diagnosis and consistent management are extremely important.”

A normal kidney measures about 10 centimeters in men and 9 centimeters in women, but in PKD patients, it can grow to tens of centimeters. It is mostly hereditary, with autosomal dominant polycystic kidney disease (ADPKD) being the most common form. If one parent has the disease, there is a 50 percent chance of passing it on to their child. The primary causes are mutations in the PKD1 gene (about 85 percent) and the PKD2 gene (about 15 percent). Additionally, autosomal recessive polycystic kidney disease (ARPKD), which is rare and typically diagnosed in childhood, also exists.

PKD is a genetic disorder that significantly threatens kidney health, ranking as the fourth leading cause of end-stage renal disease after diabetes, hypertension, and chronic glomerulonephritis. For this reason, regular checkups are essential if there is a family history of polycystic kidney disease.

Professor Choi advised, “Since a family history is often prominent, it is advisable for family members of patients to undergo early screening via kidney ultrasound or CT scans.”

PKD shows few symptoms in its early stages, but as it progresses, symptoms such as flank pain, abdominal bloating, hematuria, hypertension, frequent urinary tract infections, and kidney stones may appear. Generally, symptoms are not clearly evident before age 45. If PKD advances, kidney function can decline rapidly, potentially leading to end-stage renal failure requiring dialysis or a kidney transplant. Additionally, various complications may accompany the condition, including hypertension, cerebral aneurysms, hepatic cysts, pancreatic cysts, and heart valve disease.

Diagnosis of PKD involves imaging tests, including ultrasound, CT, and MRI, to determine the number and size of cysts. MRI is particularly useful for precisely tracking changes in kidney volume, aiding in prognosis prediction. Genetic testing may be performed during prenatal screening or prior to kidney transplantation to confirm family history or predict long-term prognosis.

Currently, there is no cure that eliminates the cysts themselves or corrects the underlying genetic defect. Treatment aims to slow the rate of kidney function decline and manage complications. In Korea, the cyst growth inhibitor tolvaptan has been introduced and is in use.

“While tolvaptan has proven effective in slowing kidney function decline, its use is limited due to side effects like thirst, polyuria, and liver function abnormalities, as well as its high cost,” Professor Choi explained.

She added that lifestyle management is also essential for those with polycystic kidney disease. A low-salt diet, adequate hydration, blood pressure control, regular exercise, and weight management are beneficial.

“Research on gene editing to address the underlying cause is currently active,” Choi said. “Polycystic kidney disease is a manageable genetic disorder. Above all, even without symptoms, getting kidney function tests every six months and managing blood pressure is the way to protect kidney health.”