History
Pain—in the abdomen, flank, or back—is the most common initial complaint, and it is almost universally present in patients with autosomal dominant polycystic kidney disease (ADPKD). The pain can be caused by any of the following:
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Enlargement of one or more cysts
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Bleeding, which may be confined inside the cyst, or lead to gross hematuria with passage of clots or a perinephric hematoma
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Urinary tract infection (eg, acute pyelonephritis, infected cysts, perinephric abscess)
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Nephrolithiasis and renal colic
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Rarely, a coincidental hypernephroma
In addition, patients with ADPKD may have abdominal pain related to definitively or presumably associated conditions. Dull aching and an uncomfortable sensation of heaviness may result from a large polycystic liver. Rarely, hepatic cysts may become infected, especially after kidney transplantation.
Abdominal pain can also result from diverticulitis, which has been reported to occur in 80% of patients with ADPKD maintained on dialysis, probably from altered connective tissue. However, this rate has not been demonstrated to be higher than the rate among other patients on dialysis.
Patients with ADPKD may be at a higher risk of developing thoracic aortic aneurysms. Abdominal aortic aneurysms are not increased among these patients.
Pain may also develop for reasons completely unrelated to the underlying disease; thus, abdominal pain in patients with ADPKD may be a diagnostic challenge.
In addition to pain, other physical symptoms that patients with early-stage ADPKD may report include fatigue, breathlessness, weakness, and malaise. [32]
Hematuria
Hematuria frequently is the presenting manifestation and usually is self-limited, lasting 1 week or less. Polycystic kidneys are unusually susceptible to traumatic injury, with hemorrhage occurring in approximately 60% of individuals. Mild trauma can lead to intrarenal hemorrhage or bleeding into the retroperitoneal space accompanied by intense pain that often requires narcotics for relief.
Physical Examination
Hypertension is one of the most common early manifestations of ADPKD. [4, 5] Even when kidney function is normal, hypertension has been found in 50-75% of patients.
The clinical course of hypertension in ADPKD is very unlike that of hypertension in chronic glomerulonephritis or tubulointerstitial nephropathies. In ADPKD, the hypertension is usually more severe early in the course of the disease and becomes less problematic as the kidney insufficiency progresses. A rise in diastolic blood pressure is the rule in ADPKD.
Palpable, bilateral flank masses occur in patients with advanced ADPKD. Nodular hepatomegaly occurs in those with severe polycystic liver disease.
Symptoms related to kidney failure (eg, pallor, uremic fetor, dry skin, edema) are rare upon presentation.
Complications
End-stage renal disease (ESRD) is the most frequent complication of ADPKD. The prevalence of hypertension increases with age, with a rate of approximately 85% in patients entering ESRD.
Polycystic liver disease
The presence of cysts in the liver, pancreas, and spleen is a well-known feature of polycystic liver disease, which is a frequent extrarenal manifestation of ADPKD. [11] Pain and infection are the only symptoms that occur from the presence of hepatic cysts. Most frequently, cysts are asymptomatic.
Polycystic liver disease belongs to a family of liver diseases characterized by an overgrowth of biliary epithelium and supportive connective tissue. It is characterized by multiple cysts that may be microscopic or can occupy most of the abdominal cavity. Liver size may range from normal to enlarged.
Women are more likely to have more and larger hepatic cysts than men; this correlates with estrogen exposure and increases with gravidity in women. Liver size in massive polycystic liver disease tends to stabilize after menopause. Hepatic cysts occur in almost 50% of affected patients. Cysts occur in approximately 20% of patients during the third decade of life and in 75% during the seventh decade of life. They are rare in children, and the frequency increases with age. Pancreatic cysts occur at a rate of 9% in patients older than 20 years.
Bilateral nephrectomy in patients with massively enlarged livers may cause portal hypertension. This typically manifests as severe ascites or esophageal varices. The enlarged liver may also cause malnutrition, and in such cases, patients may need a partial resection of the liver or hepatic transplantation.
Cerebral aneurysms
Cerebral aneurysms are among the most serious complications of ADPKD; they occur in 4-10% of patients with ADPKD. Rahman et al reported a mortality rate of approximately 7% from cerebrovascular events in patients with ADPKD. [28]
Rupture usually occurs in patients younger than 50 years who have uncontrolled hypertension; however, a stroke from hypertension and intracerebral hemorrhage is more common. There is no relationship between the risk of rupture and the severity of kidney disease.
Nephrolithiasis
Nephrolithiasis occurs in 20-30% of patients with ADPKD. Consider this condition in patients with acute pain and hematuria. In contrast to kidney stones in the general population, which most often consist of calcium oxalate, uric acid stones form in as many as 50% of patients with ADPKD. Metabolic abnormalities (eg, decreased urinary citrate) contribute to uric acid stone formation.
Establishing a diagnosis by ultrasonogram is often difficult because of the presence of large cysts. An intravenous pyelogram or a CT scan is the preferred imaging modality.
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Polycystic kidney.
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Polycystic kidney disease and massive polycystic liver disease.
