IgA Nephritis: Causes, Symptoms & Treatment

IgA nephritis is the most common disease of the renal corpuscles. It is classified as idiopathic glomerulonephritis.

What is IgA nephritis?

IgA nephritis is a kidney disease that is associated with hematuria and gradually leads to limitations in kidney function. Deposits of immunoglobulin A (IgA) on the kidney corpuscles (glomeruli) are responsible. IgA nephritis is also known as Berger’s disease or IgA nephropathy. It is one of the most common forms of glomerulonephritis. In Europe, it accounts for about 30 percent of all glomerulonephritis cases. In Asian countries such as Korea and Japan, the proportion of cases is as high as about 50 percent. IgA nephritis is two to three times more common in men than in women. The average age of onset of the disease is about 30 years. However, it can occur at any age. Most cases of the disease are sporadic. Only five percent of all cases of the disease occur in families.

Causes

The exact causes of IgA nephritis are so far in the dark. Physicians suspect hereditary predispositions related to the geographic location of the disease. Significantly elevated levels of the immunoglobulin IgA1 and immune complexes involving IgA1 are present in the blood serum of most affected individuals. Therefore, IgA is thought to be formed in the outer lymphoid mucosal tissues and is subject to structural alteration. This may be a consequence of local infections. The IgA as well as the immune complexes found in patients are often structurally altered. The more severe the disease, the more pronounced the changes. In most cases, this involves altered glycosylation, which presents to a lesser degree than in normal IgA. The reduction in binding causes the defective IgA, as well as IgA immune complexes, to attach more easily to the mesangium cells of the renal glomeruli. The increased defective IgA and IgA immune complexes can be more easily deposited in the renal corpuscles, eventually causing IgA nephritis. In this process, defective IgA is bound to the mesangial cells. The deposition of IgA antibodies in the renal corpuscles results in inflammation, which impairs filtering function. This means that the filter cells can no longer retain red blood cells and blood proteins, which are excreted in the urine. In contrast, toxic metabolites remain in the organism, leading to adverse health effects.

Symptoms, complaints and signs

IgA nephritis, which usually remains inconspicuous at first, becomes noticeable through painless macrohematuria. Macrohematuria refers to the visible appearance of blood in the urine. This is preceded by nonspecific gastrointestinal infections, respiratory infections, or pneumonia. In some cases, however, IgA nephropathy is accompanied by constant microhematuria. In this case, the blood in the urine is not visible to the naked eye, so that laboratory chemical detection must be performed. Furthermore, there is the possibility of increased excretion of protein in the urine, which is called proteinuria. Only rarely, however, does a nephrotic syndrome develop. Some patients also experience high blood pressure. Deformed red blood cells (erythrocytes) and erythrocyte cylinders may be seen in the urine. Furthermore, the IgA level in the patient’s body is elevated. In severe cases, a higher creatinine level is also present.

Diagnosis and course of the disease

Because IgA nephritis rarely causes symptoms, it is mostly diagnosed during investigations of other diseases. Laboratory values of the urine findings play an important role. Thus, a urinalysis will reveal hematuria with deformed red blood cells originating from the kidneys, as well as minor proteinuria. Sometimes the IgA level in the body is also elevated, but this is not sufficient evidence of disease. A kidney biopsy is used to confirm the diagnosis. Mesangial changes in the renal corpuscle can be detected. Furthermore, immunohistochemical detection of IgA deposits is possible. Dead cells indicate severe impairment of the renal corpuscle.It is also important to make a differential diagnosis with other glomerular diseases in which blood is present in the urine. These include primarily postinfectious glomerulonephritis, thin basement membrane syndrome, and Alport syndrome. If hematuria is the only symptom of IgA nephritis, a benign course of kidney disease usually follows. In such cases, no special treatment is required. Likewise, spontaneous improvement of proteinuria is considered to indicate a positive course. However, if IgA nephritis persists over the long term, there is a risk of hypertension (high blood pressure) and renal failure.

Complications

In most cases, IgA nephritis is diagnosed at a late stage because it usually progresses without pain and has no other visible symptoms. However, blood is found in the urine, which is not visible to the patient with the naked eye. Furthermore, various infections can occur, such as stomach infections or inflammation of the respiratory tract and lungs. This leads to respiratory problems, from which the patient may even die in the worst case. It is not uncommon for those affected to also suffer from high blood pressure, which can lead to a heart attack. Often, patients are also restricted in their daily lives, as strenuous physical activities cannot be performed. Complications can arise if IgA nephritis is not treated, leading to renal insufficiency, for example. In this case, the affected person is then dependent on lifelong dialysis or a donor kidney. IgA nephritis is treated without complications and with the help of medication. The symptoms can thus be limited. If inflammation has occurred, it is treated with the help of antibiotics. Life expectancy is usually not limited by IgA nephritis.

When should you see a doctor?

A visit to the doctor is necessary when a symptom such as blood in the urine occurs. If it occurs repeatedly and without physical exertion, this is a warning sign from the body. Because the blood is difficult to see with the naked eye in many cases due to its small quantity, the affected person should maintain increased vigilance during future toilet visits after the initial detection. If gastrointestinal problems, diarrhea, abdominal pain, constipation or lack of energy occur, a physician is needed to determine the cause. If the usual level of performance drops, internal weakness sets in or the affected person complains of a general feeling of malaise, he or she should consult a doctor. A diffuse feeling of illness, breathing disorders or a feeling of pressure in the chest should be examined and treated by a doctor. In case of anxiety or panic, a visit to the doctor is also necessary. If high blood pressure develops or disturbances of the heart rhythm set in, a doctor should be consulted. Dizziness, sleep disturbances or emotional abnormalities should be presented to a doctor if they occur repeatedly. In many cases, these signs hide diseases that need to be treated. In the case of skin changes, the development of edema or swelling on the body, a visit to the doctor is advisable. If the existing complaints increase in intensity or extent, a doctor should be consulted as soon as possible.

Treatment and therapy

There is no specific treatment available for IgA nephritis. Therapy depends on the extent and severity of kidney disease. In the early stages, no treatment is given if the creatinine level is normal. If there is persistent proteinuria or hypertension begins, the patient is given drugs such as angiotensin receptor blockers and ACE inhibitors. The cornerstones of basic therapy include lowering blood pressure. To reduce protein excretion in the urine, cortisone preparations such as glucocorticoids can also be administered. This significantly reduces the risk of renal insufficiency requiring dialysis. Glucocorticoids are administered for about six months if the proteinuria has not improved with the other medications. If there is a rapid loss of kidney function, a combination of glucocorticoids and cyclophosphamide can also be given. However, the data on this treatment option is still imprecise. The administration of immunosuppressants is viewed rather critically in recent studies.

Outlook and prognosis

The prognosis of IgA nephritis depends on the severity of the disease. However, a good course can usually be assumed.If the symptoms are mild, no therapy is necessary. However, an annual examination of kidney function, urine composition and blood pressure should then be performed. The decisive factor for therapy is the extent of protein excretion (proteinuria) in the urine. If proteinuria exceeds 0.5 grams/day, treatment is with angiotensin receptor blockers or ACE inhibitors. One gram/day must not be exceeded because it worsens the prognosis. In this case, the dose of medication must be increased until protein excretion in the urine is reduced to less than one gram per day. A much worse prognosis is observed in the presence of disseminated glomerular sclerosis. In 50 percent of these cases, renal failure develops during the course of the disease. Of these, 10 percent of patients develop such a severe form of progression that kidney transplantation becomes necessary. Even with treatment, complete kidney failure is possible in a few cases, depending on the strength of the autoimmune reactions of the immune system against the kidneys. After transplantation, 20 to 50 percent of patients may also develop IgA nephritis again, but the course is much milder. However, the new disease usually occurs more than 10 years after transplantation.

Prevention

Preventive measures against IgA nephritis do not exist. Thus, the exact causes of kidney disease could not be determined.

Follow-up

Most people affected by IgA nephritis usually do not have any special options for follow-up care. Therefore, early diagnosis should be made for IgA nephritis so that the symptoms of the disease do not worsen. Early diagnosis always has a very positive effect on the further course of the disease. Most sufferers of IgA nephritis are dependent on taking various medications. Proper dosage and regular intake should be observed. If there are any uncertainties or questions, a doctor should always be consulted first to avoid complications. In the case of IgA nephritis, regular checks by a doctor are also very important so that the situation of the disease is well monitored. An independent healing can not occur with. Often, those affected are dependent on the help and support of their own family, friends and acquaintances in their lives due to the disease. In this context, contact with others affected by the disease can also be useful, as this can often lead to an exchange of information.

What you can do yourself

There are no self-help options available to the affected person with IgA nephritis. Prevention of the disease is also usually not possible, so treatment can only be symptomatic and also not causal. Since patients very often suffer from inflammation of the lungs or respiratory tract as a result of IgA nephritis, these regions must be protected. Particularly in the cold seasons, those affected should dress appropriately to avoid discomfort and complications. The gastrointestinal tract is also frequently affected by infections, so that in many cases patients have to rely on a light, low-fat diet to avoid irritating the stomach and intestines. High blood pressure is usually treated with the help of medication. However, the patient should refrain from strenuous activities or sports and take it easy on the body. Stressful situations should also be avoided, as they can have a negative effect on the course of the disease. In the case of IgA nephritis, it is advisable to undergo a medical examination at regular intervals. In particular, the kidneys should be examined closely.