Uremic pericarditis

When the pericardial pouch, the pericardium, becomes inflamed in patients with high blood levels of urea nitrogen formed during protein metabolism, a condition called uremic pericarditis or uremic inflammation of the pericardium is diagnosed. [1]

ICD-10 code

N18.5 Uremic pericarditis.

Epidemiology

Using clinical criteria, statistics estimate the prevalence of uremic pericarditis to be in the range of 3-41%.

According to some data, uremic pericarditis associated with azotemia occurs in about 6-10% of patients with renal failure: in patients with chronic form of this disease is recorded 32-48% of cases, with acute form - 18%. In patients on hemodialysis this pathology occurs in 8-14% of cases.

As noted by WHO experts, in the last decade, the increased use of hemodialysis and improvements in the quality of this method of blood purification have reduced the incidence of uremic pericarditis to less than 20% of cases.

Causes of the uremic pericarditis

The key causes of uremic pericarditis, an inflammation of the visceral and parietal layers of the pericardial sac, are uremia or azotemia, in which the body's blood urea nitrogen level exceeds 60 mg/dL (normal is 7-20 mg/dL).

First of all, uremia occurs in acute and chronic renal failure - due to a decrease in the rate of glomerular filtration (up to ˂ 15 ml/min). Urea nitrogen levels can also increase significantly as a result of acute cardiovascular disease, prostate tumor or hyperplasia, severe dehydration, extensive burns with the development of burn disease.

In patients with end-stage renal failure (in which the glomerular filtration rate is reduced uremic pericarditis occurs most often, and it usually presents as fibrinous exudative pericarditis.

So-called "dialysis pericarditis" can develop in patients two months after dialysis initiation; it is fatal in about 8% of such patients. [2]

Read also:

• Pericarditis: general information
• Causes of chronic renal failure

Risk factors

In fact, risk factors for this disease include factors that predispose to the development of the above diseases and conditions. For example, the same chronic renal failure with uremia, including:

• chronic form of pyelonephritis and chronic inflammation of the kidney tubules - glomerulonephritis - with nephrotic syndrome;
• severe nephrolithiasis (kidney stone disease);
• Tubulointerstitial nephropathies;
• kidney damage in rheumatoid arthritis, polyarteritis nodosa, systemic lupus erythematosus and other connective tissue diseases of autoimmune nature;
• polycystic kidney disease and tumors;
• Renal artery stenosis leading to renal ischemia.

Pathogenesis

First of all, the pathogenesis of uremic pericarditis is associated with the accumulation of toxic metabolites in the body and nitrogenous "waste" in the blood, which, with insufficient renal function, are not excreted with urine.

Along with the product of transformation of arginine amino acid into ornithine - urea, there can be accumulation of glucuronic (uric) acid; ammonia formed during protein catabolism; products of energy metabolism of tissues creatinine and protein metabolism - guanidine; β2-microglobulin synthesized in increased volumes in inflammatory and autoimmune diseases and others.

As studies show, acting on pericardial tissue, these toxic metabolites cause the release of proinflammatory cytokines - interleukins (IL-1, IL-2, IL-6) and tumor necrosis factor (TNF), which leads to fibrinous aseptic inflammation (localized or diffuse), pericardial infiltration with fibrinous exudate and fibrin and collagen deposits inside the pericardial sac, formation of adhesions between the parietal and visceral layers, as well as pericardial effusions - serous and fibrinous effusion in the pericardial cavity. Hemorrhage may also occur due to damage to the pericardial microvasculature. [3]

Symptoms of the uremic pericarditis

The classic symptoms of uremic pericardial inflammation appear: [4]

• general malaise, subfebrile temperature with chills and hyperhidrosis;
• chest pain that increases when lying on the back. As a rule, the pain is localized in the left parasternal region (near the sternum), less often - in the interscapular region. The pain may irradiate to the neck and shoulder;
• shortness of breath and dry cough;
• palpitations and arrhythmias;
• with a drop in BP;
• swelling of the jugular veins;
• swelling of the feet;
• cardiomegaly.

Complications and consequences

The major life-threatening complications and sequelae of uremic pericarditis are:

• development of cardiac tamponade, which is caused by a significant serous hemorrhagic effusion into the pericardium; [5]
• pulmonary edema;
• shock.

In addition, squeezing or constrictive pericarditis may develop, in which the heart function is impaired (atrial fibrillation) due to compression by the pericardium, which has lost its elasticity.

Diagnostics of the uremic pericarditis

The diagnosis of uremic pericarditis is clinical and requires a thorough physical examination with a complete patient history.

Laboratory tests are required: general and biochemical blood tests, for blood urea nitrogen and creatinine levels, electrolyte levels, and general urinalysis.

Instrumental diagnostics include: chest x-ray, chest CT or MRI, echocardiography (ultrasound) of the heart, electrocardiography (ECG).

See also - Diagnosing pericarditis

Differential diagnosis

In cases of uremic pericarditis, differential diagnosis is made with cardiac arrhythmias, myocardial infarction, aortic or coronary artery dissection.

Treatment of the uremic pericarditis

Treatment of uremic pericarditis requires hospitalization and peritoneal dialysis or intensive hemodialysis - to lower blood urea nitrogen levels.

For pain relief (unless there is evidence of pericardial tamponade), analgesics and non-steroidal anti-inflammatory drugs are used.

The opinion of specialists regarding intrapericardial injections of corticosteroids is ambiguous, as their use is associated with the risk of hemothorax, infection, pneumothorax, cardiac arrhythmia, and in older patients - neurological complications, hyperglycemia and osteoporosis.

If dialysis treatment fails, patients with uremic pericarditis with effusion undergo pericardial puncture - pericardiocentesis (within one to two weeks). In severe uremic pericarditis with effusion leading to cardiac tamponade, emergency pericardiocentesis is required.

If the pericarditis is recurrent and the pericardial effusion is refractory symptomatic and adversely affects hemodynamics, resort to parietal pericardiectomy. [6]

Prevention

Doctors' recommendations for preventing uremic pericardial inflammation concern the timely and proper treatment of major diseases affecting kidney function, as well as the need to adhere to a healthy lifestyle and a rational diet.

Forecast

If untreated, uremic pericarditis can lead to life-threatening conditions, so the prognosis depends on early diagnosis and adequate treatment of renal failure. And when the disease is diagnosed early and treated effectively, 85-90% of patients usually recover.