How Is Glomerulonephritis Diagnosed?
Glomerulonephritis
Glomerulonephritis is the inflammation of kidney filters called glomeruli. These filters are made up of tiny blood vessels that help remove excess fluids, waste from the bloodstream, and electrolytes. This condition can happen on its own or may occur as part of chronic diseases, such as diabetes or lupus. It can also either occur gradually (chronic) or suddenly (acute). Long-term or severe inflammation that is associated with glomerulonephritis can significantly damage the kidneys. Its treatment usually depends on which type of glomerulonephritis the patient has.
The kidneys tend to abnormally function if the glomeruli are damaged. This damage can also lead to kidney failure in some people. Thus, glomerulonephritis is considered as a serious medical condition, which can become life-threatening without immediate treatment.
The kidney plays three major roles in regulating the body:
- Filters blood and produces urine
- Regulates electrolytes and fluid level in the body
- Helps in regulating blood pressure and production of red blood cells (RBCs)
Symptoms
The symptoms of glomerulonephritis usually depend on its type and severity.
Acute Glomerulonephritis Symptoms
- Facial swelling
- Low urine output
- Dark-colored urine
- Hematuria (presence of blood in urine)
- Coughing due to extra fluid in the lungs
- Hypertension or high blood pressure
Chronic Glomerulonephritis Symptoms
Chronic glomerulonephritis gradually develops without obvious symptoms. Its symptoms include:
- Proteinuria (protein in urine) and hematuria in routine urinalysis
- Hypertension (high blood pressure)
- Swollen face and ankles
- Frequent urination at night
- Abdominal pain
- Nosebleeds
- Very foamy or bubbly urine due to excess protein
Symptoms of Kidney Failure
Advanced glomerulonephritis may develop into kidney failure, which has the following symptoms:
- Loss of appetite
- Fatigue
- Nausea
- Vomiting
- Itchy and dry skin
- Nocturnal (night) muscle cramps
- Insomnia
Overview of Diagnosis
Urinalysis is the first step in the diagnosis of glomerulonephritis. The important markers of the disease are the presence of blood and protein in the urine. Glomerulonephritis can also be discovered while doing a routine physical examination for another condition. To check for important signs of kidney health, more urine tests may be required. They include:
- Creatinine clearance
- Urine protein test
- Urine concentration test
- Specific gravity of urine
- Urine osmolality
Blood tests may show the following:
Doctors may also order any of the following immunologic tests:
- Antineutrophil cytoplasmic antibodies (ANCA)
- Anti-glomerular basement membrane antibody
- Antinuclear antibodies (ANA)
- Complement levels
The results will indicate whether your kidneys are being damaged by the immune system.
To confirm the diagnosis, a kidney biopsy may be required. In this procedure, a needle is used to collect a small sample of the patient's kidney tissue. The sample is then analyzed in the laboratory. The doctor may also order the following imaging tests to learn more about the patient's condition:
- CT scan
- Renal ultrasound
- Chest X-ray
- Intravenous pyelogram
The following are tests that can help assess kidney function:
Urine Test
The presence of red blood cells and red blood cell casts in the urine may indicate a possible glomeruli damage. White blood cells (WBCs) might also show up in the urine test. The presence of WBCs in urine usually indicates infection, inflammation, and increased protein levels. It may also indicate damaged nephrons. Other red flag indicators are increased levels of urea and creatinine.
Blood Tests
Information about kidney damage can also be obtained through blood tests. Measuring the level of waste products in the blood can also help identify glomeruli impairment.
As a part of their usual role, the kidneys remove creatinine from the blood. The creatinine level will rise if the kidneys are abnormally functioning. An estimated glomerular filtration rate is obtained from the creatinine result and can help determine if the kidneys are properly functioning.
If further investigation is needed for the kidney problem, an ultrasound scan of the kidney will be required. By doing this scan, specialists can take a look at the images of the kidney using high-frequency sound waves. The size of the kidneys will be checked by the specialist along with making sure that there are no blockages present. Moreover, a kidney ultrasound scan is usually done before having a kidney biopsy.
Imaging Tests
The doctor may recommend diagnostic studies if he or she detects evidence of kidney damage. These diagnostic studies allow the visualization of the kidneys. These imaging tests include an ultrasound of the kidney, a CT scan, or a kidney X-ray.
Kidney Biopsy
In this procedure, small pieces of the kidney tissue are collected by a special needle for microscopic examination. The cause of the inflammation can be determined through a kidney biopsy. To confirm the diagnosis of glomerulonephritis, a kidney biopsy is always necessary. This procedure is done if glomerulonephritis is suspected. It is usually carried out under local anesthesia to numb the area, where the biopsy needle is inserted.
To locate the kidneys, an ultrasound machine will be used, and to take the sample, a needle is used. Patients who will undergo a kidney biopsy would need to remain in the hospital on the day of the procedure since this procedure may carry some risk of bleeding. Sometimes, the person may have to stay in the hospital overnight.
The process of kidney damage is slow but progressive. At first, the symptoms are not obvious. Unfortunately, before any symptoms are noticed, a lot of damage is already done. Your doctor will review your medical history if glomerulonephritis is suspected. After obtaining your history, the doctor will do a physical exam and may order any of the following tests:
- Blood tests
- Urine tests
- Abdominal or kidney ultrasound
- Kidney or abdominal CT scan
- Intravenous pyelogram (an X-ray examination of the ureters, kidney, and urinary bladder)
- If heart failure is suspected, then a chest X-ray may be ordered
- Kidney biopsy
The most reliable way to identify this condition from other kidney disorders is through a kidney biopsy. In advanced stages, however, a kidney biopsy is rarely done. The reason is that the kidney has already shrunk in these cases. The kidney would also be scarred. Even on an imaging test, the kidney appears abnormally small.
