How is Congenital Nephrotic Syndrome Finnish Type diagnosed?

Congenital Nephrotic Syndrome Finnish Type (CNF) is a rare genetic disorder that affects the kidneys, leading to excessive protein loss in the urine. It is primarily found in individuals of Finnish descent, hence the name. Diagnosing CNF involves a combination of clinical evaluation, laboratory tests, and genetic analysis.

Clinical Evaluation:

The first step in diagnosing CNF is a thorough clinical evaluation by a healthcare professional. They will review the patient's medical history, assess symptoms, and perform a physical examination. The characteristic signs of CNF include edema (swelling), foamy urine (due to proteinuria), and low levels of albumin in the blood.

Laboratory Tests:

Several laboratory tests are essential in diagnosing CNF:

• Urine Analysis: A urine sample is collected and analyzed to measure protein levels. In CNF, proteinuria is typically present, indicating excessive protein loss through the kidneys.


• Blood Tests: Blood samples are taken to measure the levels of albumin, cholesterol, and other markers. CNF patients often have low albumin levels and high cholesterol levels.


• Kidney Function Tests: These tests evaluate how well the kidneys are functioning. They include measuring creatinine and blood urea nitrogen (BUN) levels. In CNF, kidney function may be impaired.


• Electrolyte Levels: Imbalances in electrolytes, such as sodium and potassium, can occur in CNF. Blood tests help identify any abnormalities.

Genetic Analysis:

Genetic analysis plays a crucial role in confirming the diagnosis of CNF. It involves identifying mutations in the NPHS1 gene, which is responsible for encoding a protein called nephrin. Mutations in this gene disrupt the normal functioning of the glomerular filtration barrier in the kidneys, leading to protein leakage.

A blood sample is collected from the patient, and DNA sequencing techniques are used to analyze the NPHS1 gene. Genetic testing can identify specific mutations that are associated with CNF. However, it is important to note that not all cases of CNF may have identifiable mutations, as there may be other genetic factors involved.

Additional Investigations:

In some cases, additional investigations may be required to assess the extent of kidney damage and rule out other potential causes of nephrotic syndrome. These may include:

• Kidney Biopsy: A small sample of kidney tissue is obtained through a biopsy procedure. It helps evaluate the structure and function of the kidneys, providing valuable information about the underlying cause of nephrotic syndrome.


• Imaging Studies: Imaging techniques like ultrasound or CT scan may be used to visualize the kidneys and identify any structural abnormalities.

Once the diagnosis of CNF is confirmed, appropriate management strategies can be implemented. Treatment typically involves supportive measures to control symptoms, such as diuretics to reduce edema and medications to manage complications. Genetic counseling is also recommended for affected individuals and their families to understand the inheritance pattern and potential risks for future pregnancies.