Nephritic Syndrome - Specialists and Information

Nephritic syndrome is diagnosed when three symptoms are present:

• Hematuria (blood in the urine)
• Hypertension (high blood pressure—newly developed)
• Edema (fluid retention in the subcutaneous tissue)

The following may also occur:

• Proteinuria (protein in the urine)
• Swollen face
• Flank pain
• Headaches
• limb pain
• epileptic seizures
• Pulmonary edema
• Shortness of breath

Blood in the urine @ GladkovPhoto /AdobeStock

Hematuria is a key symptom among all others. For the doctor, red blood cells are either visible in the urine or can be detected through laboratory testing. In addition, protein is excreted in the urine (proteinuria). In both cases, this sometimes goes unnoticed by those affected.

Doctors only diagnose nephrotic syndrome when high blood pressure and edema (fluid retention) are also present. In the early stages, edema primarily appears on the eyelids, causing the patient’s face to appear swollen.

Other symptoms include:

• flank pain as well as
• headaches and limb pain

If there is a severe electrolyte imbalance, it can lead to epileptic seizures. If high blood pressure is severe, it often results in shortness of breath and pulmonary edema.

 Flank pain is common @ fadfebrian /AdobeStock

A dangerous complication of nephritic syndrome is a severe deterioration in kidney function. This can develop within a few days as a result of bilateral inflammation of the kidneys involving the glomeruli. In the worst-case scenario, acute kidney failure occurs.

Nephritic syndrome is most often caused by inflammation of the glomeruli, frequently following a streptococcal infection. Lupus nephritis, an autoimmune disease, can also trigger inflammation.

These pathological changes are highly diverse, and their causes have not yet been fully elucidated. Consequently, physicians have not yet been able to identify specific risk factors for the development of the disease.

However, autoimmune diseases—such as lupus nephritis or systemic lupus erythematosus (SLE)—play a significant role time and again. SLE initially affects only the skin but can spread to other organs, including the kidneys.

A few weeks after a strep throat caused by Streptococcus pyogenes, post-infectious inflammation of the glomeruli may occur. This is due to abnormal immune processes.

In this process, it is not the bacteria themselves that attack the kidneys, but antigen-antibody complexes (immune complexes). After the infection has run its course, these complexes attack proteins that resemble the bacteria.

This causes the smallest blood vessels in the kidneys, located in the glomeruli, to become blocked. The backflow of blood in the glomeruli raises blood pressure, and blood cells enter the urine. In other parts of the body, fluid leaks out of the congested blood vessels, leading to the formation of edema.

The diagnosis is based on the three main symptoms:

• Hematuria
• Edema and
• hypertension, as well as
• other clinical findings, such as flank pain

A detailed medical history (discussion of the patient’s medical history) is followed by a physical examination. For example, the doctor may ask if you’ve ever had tonsillitis.

During the physical examination, the doctor determines whether there is fluid retention in the tissues (edema).

Blood and urine tests are also of great importance. An additional ultrasound examination can visualize the disease process and provide further insight into its causes.

In cases of severe or difficult-to-assess nephritic syndrome, a kidney biopsy is necessary. During this procedure, the doctor takes a tissue sample from the kidney.

Ultrasound examination of the kidney @ LIGHTFIELD STUDIOS /AdobeStock

Treatment of nephrotic syndrome is based on the symptoms. For example, doctors treat high blood pressure with antihypertensive medications, known as ACE inhibitors.

If there are signs of fluid retention, a strict diet with restricted salt and fluid intake is prescribed. Diuretics may also be used. 

Patients must also follow a low-protein diet. Physical rest and bed rest are also recommended.

In nephrotic syndrome, it is important to monitor blood values—especially creatinine—regularly. The creatinine level in the blood provides information about kidney function. An increase in this blood value is an indication of incipient kidney failure.In cases of nephritic syndrome, it is important to monitor blood values—especially creatinine—regularly @ New Africa /AdobeStock

If a streptococcal infection is the cause of nephritic syndrome, preventive treatment with the antibiotic penicillin is administered for ten days.