Kidneys and alcohol (alcoholic nephropathy)

Alcoholic nephropathy is associated with the effect of chronic alcohol on the immune system due to a direct membrane-toxicity effect on the production of cytokines, and due to a violation of the regulation of immunity in the central nervous system and the liver. An important role is played by sensitization to the antigen of alcoholic hyaline, bacterial antigens, acceleration of replication of HCV. Almost half of patients with visceral form of alcoholism have HCV-RNA, as well as an increase in the concentration of E. Coli endotoxin, which activates the complement system via an alternative pathway.

[1], [2], [3], [4]

Causes of the alcohol nephropathy

Among non-inflammatory nephritogenic factors, "alcoholic" hypertension and abnormalities of purine metabolism are distinguished (see  Gouty nephropathy ). The risk of developing hypertension increases with the increase in the amount of alcohol consumed and reaches 90% with the intake of more than 35 g / day. Morphologically alcoholic glomerulonephritis belongs to the group of secondary IgA-nephritis, it is characterized by a picture of mesangioproliferative nephritis (more often - focal, less often - diffuse).

[5], [6]

Symptoms of the alcohol nephropathy

Symptoms of alcohol nephropathy are manifested in the symptoms of latent nephritis: persistent painless microhematuria, combined with minimal or moderate proteinuria (less than 2 g / day).

An acute non-fungal syndrome, often accompanied by an increase in microhematuria,  proteinuria, oliguria, and a transient decrease in CF, is observed in more than 1/3 of patients on the 1st day after an alcoholic excess.

Hypertonic and nephrotic forms of alcoholic glomerulonephritis are diagnosed much less often. The nephrotic form is characteristic for the rapidly progressive and diffuse fibroplastic variants of alcoholic glomerulonephritis. In hypertensive form of alcoholic glomerulonephritis, purine metabolism (hyperuricemia, hyperuricosuria) and obesity are often detected. Antihypertensive drugs satisfactorily control blood pressure. For all forms of alcoholic glomerulonephritis are typical:

• mesangial IgA-deposits;
• the severity of renal interstitial fibrosis;
• the presence of extrarenal symptoms of alcoholic illness.

More than half of the cases show such diseases as alcoholic liver disease (chronic hepatitis, portal cirrhosis of the liver), chronic pancreatitis, alcoholic cardiomyopathy, peripheral polyneuropathy.

[7], [8], [9]

Forms

The following clinical forms of glomerulonephritis are distinguished:

• latent;
• hypertensive;
• nephrotic.

[10], [11], [12]

Diagnostics of the alcohol nephropathy

Inspection and Physical Examination

Stigma of alcoholic illness is found:

• macrocytic anemia;
• Dupuytren's contracture;
• giant parotitis;
• erythema of the palms;
• gynecomastia.

[13], [14]

Laboratory Diagnostics of Alcohol Nephropathy

• General urine analysis : microhematuria, proteinuria.
• Reducing the speed of CF.
• Immunological examination of blood: persistent increase in IgA levels.
• Hyperuricemia, hyperuricosuria.

Instrumental diagnostics of alcohol nephropathy

Use ultrasonic, X-ray and radionuclide methods of diagnosis, liver biopsy.

Differential diagnosis

Diagnosis of alcohol nephropathy is often complicated due to the nonspecificity of hematuria and the variety of symptoms of alcoholic illness. First of all, a complex of radionuclide, ultrasound and X-ray diagnostic methods is used to exclude urological diseases accompanied by hematuria (nephrolithiasis, urinary system tumors, kidney tuberculosis, necrotic papillitis with purulent pyelonephritis).

The next stage of differential diagnosis of alcohol nephropathy is the differentiation of alcohol glomerulonephritis with acute nephritis, with primary and secondary IgA-nephritis, with gouty and psoriatic nephropathy. In alcohol glomerulonephritis, unlike acute nephritis and Berger's disease, less common are hematuria, the episode of hematuria is not associated with a previous acute infection of the upper respiratory tract (tonsillitis, pharyngitis), but with alcoholic excesses. Often there are symptoms of alcoholic illness of the liver, myocardium, pancreas.

Liver biopsy plays an important role in establishing the alcohol etiology of glomerulonephritis and the choice of adequate therapy.

Rapidly progressive alcoholic nephritis should be differentiated from the following conditions:

• diffuse nephritis in subacute infective endocarditis;
• hepatorenal syndrome;
• endotoxic shock (see Acute Renal Failure);
• apostematous nephritis;
• secondary IgG nephritis in carriers of HIV infection (IgA-nephritis, which often develops in HIV-infected individuals of the white race, is characterized by diffuse extracapillary proliferation and rapidly progressive course).

Treatment of the alcohol nephropathy

First of all, it is necessary to completely eliminate alcoholic beverages, which leads to a rapid development of remission of jade in 50-60% of cases.

With alcohol glomerulonephritis with impaired purine metabolism, non-corrective abstinence and low-purine diet, treatment with allopurinol is indicated.

With nephrotic and rapidly progressive forms of glomerulonephritis, glucocorticoids, cytostatics, antiviral drugs (with HCV replication) are used, however, the effectiveness of pathogenetic therapy of alcoholic CGN has not been proven.

When prescribing antihypertensive therapy should avoid hepatotoxic drugs (methyldopa, thiazide diuretics, ganglioblokatory). The systematic use of loop diuretics exacerbates hyperuricemia, a deficiency of potassium and calcium, and with concomitant portal cirrhosis causes the development of hepatorenal syndrome. Among antihypertensive drugs, ACE inhibitors, angiotensin II receptor blockers, calcium channel blockers, beta-blockers are most preferred.

Treatment of chronic renal failure

The use of regular intermittent hemodialysis is difficult due to the instability of hemodynamics (cirrhosis of the liver with the syndrome of portal hypertension, hypovolemia, alcoholic cardiomyopathy with systolic dysfunction), severe hemorrhagic syndrome, metabolic disorders (respiratory alkalosis, hepatic encephalopathy). More effective and safe CAPD.

When kidney transplantation patients with alcoholic glomerulonephritis increased the risk of infectious and oncological complications, as well as acute hepatic insufficiency. With glomerulonephritis, associated with alcoholic cirrhosis of the liver, combined transplantation - kidney and liver - is advisable.

Forecast

The course and prognosis of alcohol nephropathy are relatively favorable.

Almost half of patients observe a recurring course of chronic glomerulonephritis with exacerbations after another alcoholic excess and rapid (for 3-4 weeks) regression with abstinence. In parallel with the decrease in the severity of proteinuria, microhematuria, hypertension and normalization of CF, positive dynamics of cholestasis syndrome (reduction in liver size), breaches of purine metabolism, cardiomyopathy (restoration of sinus rhythm) are noted.

Persistent flow is characterized by a constant activity of chronic glomerulonephritis, clearly not associated with alcoholic excesses.

Rapidly progressing course of alcohol nephropathy with the outcome of irreversible kidney failure in the 1-2-th year of nephritis is met in 3-6% of cases - with far-gone alcoholic illness. The morphological basis of this variant is diffuse extracapillary or mesangiocapillary nephritis. There is a connection between the rapidly progressing course of alcoholic chronic glomerulonephritis with persistent viral (HCV) infection, severe exacerbation of alcoholic pancreatitis.

In general, 15-20% of patients in the 10th year of chronic glomerulonephritis develop terminal chronic renal failure.

The criteria for an unfavorable prognosis of alcoholic chronic glomerulonephritis include:

• persistent proteinuria more than 1 g / day;
• formation of a nephrotic syndrome;
• persistent hypertension;
• long-term (more than 10 years) alcohol consumption;
• HCV replication.

[15],