Practice Essentials
Autosomal dominant polycystic kidney disease (ADPKD) is a multisystemic and progressive disorder characterized by cyst formation and enlargement in the kidney (see the image below) and other organs (eg, liver, pancreas, spleen).
Up to 50% of patients with ADPKD require renal replacement therapy by 60 years of age.
Polycystic kidney.
Signs and symptoms
Pain—in the abdomen, flank, or back—is the most common initial complaint, and it is almost universally present in patients with ADPKD. Dull aching and an uncomfortable sensation of heaviness may result from a large polycystic liver.
The pain can be caused by any of the following:
Enlargement of one or more cysts
Bleeding: May be confined inside the cyst or lead to gross hematuria with passage of clots or a perinephric hematoma
UTI (eg, acute pyelonephritis, infected cysts, perinephric abscess)
Nephrolithiasis and renal colic
Rarely, a coincidental hypernephroma
See Presentation for more detail.
Diagnosis
Examination in patients with ADPKD may demonstrate the following:
Hypertension: One of the most common early manifestations of ADPKD,
in which increased diastolic BP is the rule; clinical course in ADPKD is usually more severe early on, then becomes less problematic as the renal insufficiency progresses
Palpable, bilateral flank masses: In advanced ADPKD
Nodular hepatomegaly: In severe polycystic liver disease
Rarely, symptoms related to renal failure (eg, pallor, uremic fetor, dry skin, edema)
Testing
Routine laboratory studies include the following:
Serum chemistry profile, including calcium and phosphorus
CBC count
Urinalysis
Urine culture
Uric acid determination
Intact PTH assay
Genetic testing may be performed, in which the major indication is for genetic screening in young adults with negative ultrasonographic findings who are being considered as potential kidney donors.
Staging
Staging of renal failure is by glomerular filtration rate (GFR), as follows:
Stage 1: GFR above 90 mL/min
Stage 2: GFR 60-90 mL/min
Stage 3: GFR 30-60 mL/min
Stage 4: GFR 15-30 mL/min
Stage 5: GFR below 15 mL/min
Imaging studies
Radiologic studies used in the evaluation of ADPKD include the following:
Ultrasonography: Technique of choice for patients with ADPKD and for screening patients’ family members; useful for exploring abdominal extrarenal features of ADPKD (eg, liver cysts, pancreatic cysts)
CT scanning: Not routine; useful in doubtful pediatric cases or in complicated cases (eg, kidney stone, suspected tumor)
MRI: Not routine; helpful in distinguishing renal cell carcinoma from simple cysts; criterion standard to help determine renal volume for clinical trials when testing drugs for ADPKD; best imaging tool for monitoring kidney size after treatment, as an indication of disease progress.
MRA: Not routine; preferred imaging technique for diagnosing ADPKD-related intracranial aneurysms
Ultrasonographic diagnostic criteria for ADPKD1 are as follows
:
At least 2 cysts in 1 kidney or 1 cyst in each kidney in an at-risk patient younger than 30 years
At least 2 cysts in each kidney in an at-risk patient aged 30-59 years
At least 4 cysts in each kidney for an at-risk patient aged 60 years or older
Ultrasonographic diagnostic criteria for ADPKD in patients with a family history but unknown genotype are as follows
:
Three or more (unilateral or bilateral) renal cysts in patients aged 15-39 years
Two or more cysts in each kidney in patients aged 30-59 years
Fewer than 2 renal cysts in the findings provides a negative predictive value of 100% and can be considered sufficient for ruling out disease in at-risk individuals older than 40 years.
Indications for MRA are as follows
:
Family history of stroke or intracranial aneurysms
Development of symptoms suggesting an intracranial aneurysm
Job or hobby in which a loss of consciousness may be lethal
Past history of intracranial aneurysms
See Workup for more detail.
Management
Management of ADPKD includes the following:
Control blood pressure: Drugs of choice are ACEIs (eg, captopril, enalapril, lisinopril) or ARBs (eg, valsartan, telmisartan, losartan, irbesartan, candesartan, olmesartan)
Control abnormalities related to renal failure: Drugs to maintain electrolyte levels (eg, calcium carbonate, calcium acetate, sevelamer, lanthanum carbonate, calcitriol [possibly], diuretics, blood pressure medications)
Treat UTIs
Treat cyst infections: Gyrase inhibitors (eg, ciprofloxacin, chloramphenicol, clindamycin, levofloxacin); dihydrofolic acid inhibitors (TMX/SMP)
Treat hematuria: Possibly analgesic plus copious oral hydration
Reduce abdominal pain produced by enlarged kidneys
Prevent cardiac valve infection in patients with intrinsic valve disease
Reduce kidney function decline in adults at risk of rapidly progressive ADPKD (tolvaptan [Jynarque])
Surgical intervention in ADPKD includes the following:
Surgical drainage: Usually in conjunction with ultrasonographically guided puncture; in cases of infected renal/hepatic cysts not responding to conventional antibiotics
Open or fiberoptic-guided surgery: For excision/drainage of the outer walls of cysts to ablate symptoms
Nephrectomy: Last resort for pain control in patients with inaccessible cysts in the renal medullae; bilateral nephrectomy in patients with severe hepatic involvement
Partial hepatectomy: To manage massive hepatomegaly
Liver transplantation: In cases of portal hypertension due to polycystic liver or hepatomegaly with nonresectable areas
Patients with ADPKD who progress to end-stage renal disease may require the following procedures:
Hemodialysis
Peritoneal dialysis
Renal transplantation
See Treatment and Medication for more detail. For a discussion of ADPKD in children, see Pediatric Polycystic Kidney Disease.