Polycystic Kidney Disease Treatment & Management

Pharmacologic therapy is necessary to accomplish the following:

• Control blood pressure
• Control abnormalities related to renal failure
• Treat urinary tract infections
• Treat hematuria
• Reduce abdominal pain produced by enlarged kidneys

Patients with autosomal dominant polycystic kidney disease (ADPKD) who progress to end-stage renal disease may require hemodialysis, peritoneal dialysis, or renal transplantation. For more information, see the Medscape Reference articles Chronic Kidney Disease and Renal Transplantation.

In patients with heart murmurs, institute routine American Heart Association antibiotic prophylaxis.

A study by Torres et al identified serum high-density lipoprotein (HDL) cholesterol, urine sodium excretion (U_Na V), and 24-hour osmolality as having a likely effect on ADPKD progression.^[24] Whether modification of these components influences the clinical course of ADPKD remains unclear.

Several classes of drugs have been identified as having potential benefit in ADPKD (eg, vasopressin-2-receptor antagonists, mammalian targets of rapamycin [mTOR] inhibitors).^{[25, 26]} Clinicians may wish to refer patients for inclusion of clinical trials.^{[27, 28]}

Metabolic problems related to renal failure that need to be controlled include the following:

• Hyperkalemia
• Hyperphosphatemia
• Hypocalcemia
• Hyperparathyroidism
• Metabolic acidosis

Diet and activity

Although a low-salt diet is recommended when hypertension or renal failure is present, no other special diet reportedly is of benefit.

Patients should avoid contact sports in which direct trauma to the back or abdomen is likely. This is especially important with larger, palpable kidneys in order to minimize the risk of rupture.

In patients with renal disease, the goal is a blood pressure of less than 130/88 mm Hg. If more than 1 g/day of urinary protein is present, the target blood pressure is less than 125/75 mm Hg. Achieving good blood pressure control helps slow the progression of renal disease.^[29] A study by Patch et al showed that when intensity and coverage of antihypertensive therapy were increased, mortality decreased for patients with ADPKD.^[30]

The drugs of choice for this condition are angiotensin-converting enzyme (ACE) inhibitors (ie, captopril, enalapril, lisinopril) or angiotensin II receptor blockers (ARBs) such as telmisartan, losartan, irbesartan, and candesartan. These agents remain the most recommended drugs to treat hypertension in patients with ADPKD, although studies of the renin-angiotensin-aldosterone system have not convincingly demonstrated that it plays an important role in its pathogenesis. Calcium channel blockers are not recommended.

In patients with advanced renal disease, ACE inhibitors and ARBs can exacerbate renal failure or increase serum potassium levels; therefore, regularly monitor use with serum chemistry values.

Urinary tract infections (UTIs) occur in 30-50% of ADPKD patients and most frequently in women. Gram-negative bacteria are the most common pathogens.

Distinguishing between infections of the bladder, renal parenchyma, and cysts is important because the treatment for each condition is different. Treating infected cysts requires antibiotics that penetrate into the cyst. Useful agents are ciprofloxacin, trimethoprim-sulfamethoxazole, clindamycin, and chloramphenicol.

Hematuria

Hematuria is frequent in patients with ADPKD. It usually results from cyst rupture or stone passage. Instruct the patient to drink large amounts of water, to rest, and to take a pain killer if necessary. Hematuria is usually self-limited. Hospitalization is necessary if the patient is still bleeding after several days or if the amount of blood is substantial.

Abdominal pain from enlarged kidneys

Avoid nonsteroidal anti-inflammatory drugs (NSAIDs), because they can worsen renal function and potentiate hyperkalemia. Treatment involves surgical cyst decompression which is effective for pain relief in 60-80% of patients. See Surgical Drainage, below.

If infected renal or hepatic cysts do not respond to conventional antibiotic therapy, surgical drainage may be necessary. This procedure is usually performed with ultrasonographically guided puncture.^[31]

Cysts may become large enough to cause abdominal discomfort or pain. Typically, acute pain is from cyst hemorrhage or an obstruction by a clot, stone, or infection.^[32] When one or more cysts can be identified as causing the pain, the symptoms can often be abated by open- or fiberoptic–guided surgery to excise the outer walls and to drain them.

Approximately 25% of patients with the most severe pain do not gain relief from surgery or pharmacologic therapy with narcotics. These individuals usually have inaccessible cysts in the medullary portions of the kidneys. Nephrectomy is used as a last resort to control the pain in these patients. Nephrectomy is often necessary when there is not enough room for a kidney graft.

Severe polycystic liver disease can result in massive hepatomegaly (see image below). When the liver becomes so large that it prevents the patient from obtaining normal nutrition or causes severe abdominal discomfort, a surgical procedure is necessary. Surgical intervention may range from unroofing several cysts to a partial hepatectomy.

Partial hepatectomy is difficult because of the characteristics of the polycystic liver. Only very expert surgeons should proceed with this surgical procedure.

When the polycystic liver causes portal hypertension or is very large with nonresectable areas, liver transplantation may be necessary.

Special attention should be paid when bilateral nephrectomy has to be carried out in patients with severe liver involvement. Several cases of refractory ascites after bilateral nephrectomy have been reported in these patients.

Consultations may be indicated under the following circumstances:

• Nephrologist upon evidence of renal insufficiency, hypertension, microalbuminuria, or concentrating defect
• Invasive radiologist for cyst sclerosis or drainage
• General surgeon for nephrectomy, cyst decompression, unroofing, or surgical hepatic procedures
• Neurosurgeon for ICAs
• Cardiologist for valvular abnormalities

Ensure that a patient with ADPKD who is nonhypertensive and has normal renal function undergoes blood testing and ultrasonography of the kidneys every 1-2 years.

Schedule more frequent follow-up studies for patients with high blood pressure. Hypertension is common, occurring in as many as 50-70% of patients before the onset of renal failure.

Patients with renal failure require more frequent monitoring, based on the severity of their condition.