what it is ?

what is it?

The nephrotic syndrome is defined by a urinary protein level exceeding 3.5 g per 1.73 m of body surface area per day.It is difficult to define the appropriate level of protein restriction in patients with Nephrotic Syndrome..

Nephrotic syndrome is a nonspecific kidney disorder characterised by a number of signs of disease: proteinuria, hypoalbuminemia and edema. It is characterized by an increase in permeability of the capillary walls of the glomerulus leading to the presence of high levels of protein passing from the blood into the urine (proteinuria at least 3.5 grams per day per 1.73m2 body surface area); low levels of protein in the blood (hypoproteinemia or hypoalbuminemia), ascites and in some cases, edema; high cholesterol (hyperlipidaemia or hyperlipemia) and a predisposition for coagulation.

Causes of Nephrotic Syndrome

Nephrotic syndrome has many causes and may either be the result of a glomerular disease that can be either limited to the kidney, called primary nephrotic syndrome (primary glomerulonephritis), or a condition that affects the kidney and other parts of the body, called secondary nephrotic syndrome.

Primary glomerulonephritis

Primary causes of nephrotic syndrome are usually described by their histology:

Minimal change disease : is the most common cause of nephrotic syndrome in children. It owes its name to the fact that the nephrons appear normal when viewed with an optical microscope as the lesions are only visible using an electron microscope. Another symptom is a pronounced proteinuria.

Focal segmental glomerulosclerosis : is the most common cause of nephrotic syndrome in adults. It is characterized by the appearance of tissue scarring in the glomeruli. The term focal is used as some of the glomeruli have scars, while others appear intact; the term segmental refers to the fact that only part of the glomerulus suffers the damage.

Membranous glomerulonephritis : The inflammation of the glomerular membrane causes increased leaking in the kidney.

Mesangial proliferative glomerulonephritis : is the inflammation of the glomeruli along with the deposit of antibodies in their membranes, which makes filtration difficult.

Rapidly progressive glomerulonephritis : A patient’s glomeruli are present in a crescent moon shape. It is characterized clinically by a rapid decrease in the glomerular filtration rate (GFR) by at least 50% over a short period, usually from a few days to 3 months.

Secondary glomerulonephritis

Secondary causes of nephrotic syndrome have the same histologic patterns as the primary causes, though they may exhibit some difference suggesting a secondary cause, such as inclusion bodies.[5] They are usually described by the underlying cause.

Diabetic nephropathy: is a complication that occurs in some diabetics. Excess blood sugar accumulates in the kidney causing them to become inflamed and unable to carry out their normal function. This leads to the leakage of proteins into the urine.

Systemic lupus erythematosus: this autoimmune disease can affect a number of organs, among them the kidney, due to the deposit of immunocomplexes that are typical to this disease. The disease can also cause lupus nephritis.

Sarcoidosis: This disease does not usually affect the kidney but, on occasions, the accumulation of inflammatorygranulomas (collection of immune cells) in the glomeruli can lead to nephrotic syndrome.

Syphilis: kidney damage can occur during the secondary stage of this disease (between 2 and 8 weeks from onset).

Hepatitis B: certain antigens present during hepatitis can accumulate in the kidneys and damage them.

Sjögren's syndrome: this autoimmune disease causes the deposit of immunocomplexes in the glomeruli, causing them to become inflamed, this is the same mechanism as occurs in systemic lupus erythematosus.