Nephrotic syndrome
Encyclopedia
- Not to be confused with nephritic syndromeNephritic syndromeNephritic syndrome is a collection of signs associated with disorders affecting the kidneys, more specifically glomerular disorders. It is characterized by having small pores in the podocytes of the glomerulus, large enough to permit proteins and red blood cells to pass into the urine...
Nephrotic syndrome is a nonspecific disorder in which the kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
s are damaged, causing them to leak large amounts of protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
(proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
at least 3.5 grams per day per 1.73m2 body surface area) from the blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
into the urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
.
Kidneys affected by nephrotic syndrome have small pores in the podocyte
Podocyte
Podocytes are cells in the Bowman's capsule in the kidneys that wrap around the capillaries of the glomerulus...
s, large enough to permit proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
(and subsequently hypoalbuminemia
Hypoalbuminemia
Hypoalbuminemia is a medical condition where levels of albumin in blood serum are abnormally low. It is a specific form of hypoproteinemia.Albumin is a major protein in the human body, making up about 60% of total human plasma protein by mass...
, because some of the protein albumin
Albumin
Albumin refers generally to any protein that is water soluble, which is moderately soluble in concentrated salt solutions, and experiences heat denaturation. They are commonly found in blood plasma, and are unique to other blood proteins in that they are not glycosylated...
has gone from the blood to the urine) but not large enough to allow cells through (hence no hematuria
Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
). By contrast, in nephritic syndrome
Nephritic syndrome
Nephritic syndrome is a collection of signs associated with disorders affecting the kidneys, more specifically glomerular disorders. It is characterized by having small pores in the podocytes of the glomerulus, large enough to permit proteins and red blood cells to pass into the urine...
, RBC
Red blood cell
Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...
s pass through the pores, causing hematuria
Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
.
According to NephCure, most often, Nephrotic Syndrome is defined by its primary diseases that attack the kidney’s filtering system. Some of these cases are idiopathic
Idiopathic
Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...
.
Signs and symptoms
It is characterized by proteinuriaProteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
(>3.5g/day), hypoalbuminemia
Hypoalbuminemia
Hypoalbuminemia is a medical condition where levels of albumin in blood serum are abnormally low. It is a specific form of hypoproteinemia.Albumin is a major protein in the human body, making up about 60% of total human plasma protein by mass...
, hyperlipidemia
Hyperlipidemia
Hyperlipidemia, hyperlipoproteinemia, or hyperlipidaemia is the condition of abnormally elevated levels of any or all lipids and/or lipoproteins in the blood...
and edema
Edema
Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
which is generalized & also known as anasarca
Anasarca
Anasarca, also known as "extreme generalized edema" is a medical condition characterised by widespread swelling of the skin due to effusion of fluid into the extracellular space....
or dropsy. Common among 2–6 years old boys. The edema begins in the face. Lipiduria
Lipiduria
Lipiduria, also termed Lipuria, is the presence of lipids in the urine.Lipuria is most frequently observed in nephrotic syndrome where it is passed as lipoproteins along with other proteins....
(lipids in urine) can also occur, but is not essential for the diagnosis of nephrotic syndrome. Hyponatremia
Hyponatremia
Hyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal. In the vast majority of cases, hyponatremia occurs as a result of excess body water diluting the serum sodium and is not due to sodium deficiency. Sodium is the dominant extracellular...
also occurs with a low fractional sodium excretion
Fractional sodium excretion
The fractional excretion of sodium is the percentage of the sodium filtered by the kidney which is excreted in the urine. It is measured in terms of plasma and urine sodium, rather than by the interpretation of urinary sodium concentration alone, as urinary sodium concentrations can vary with...
.
Hyperlipidemia is caused by two factors:
- Hypoproteinemia stimulates protein synthesis in the liver, resulting in the overproduction of lipoproteins.
- Lipid catabolism is decreased due to lower levels of lipoprotein lipase, the main enzyme involved in lipoprotein breakdown.
A few other characteristics seen in nephrotic syndrome are:
- The most common sign is excess fluid in the body due to the serum hypoalbuminemia. Lower serum oncotic pressure causes fluid to accumulate in the interstitial tissues. Sodium and water retention aggravate the edema. This may take several forms:
- Puffiness around the eyes, characteristically in the morning.
- Pitting edemaEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
over the legLegŁęg may refer to the following places in Poland:*A former name for the town of Ełk *Part of the Czyżyny district of Kraków*Łęg, Pleszew County in Greater Poland Voivodeship...
s. - Fluid in the pleural cavityPleural cavityIn human anatomy, the pleural cavity is the potential space between the two pleura of the lungs. The pleura is a serous membrane which folds back onto itself to form a two-layered, membrane structure. The thin space between the two pleural layers is known as the pleural cavity; it normally...
causing pleural effusionPleural effusionPleural effusion is excess fluid that accumulates between the two pleural layers, the fluid-filled space that surrounds the lungs. Excessive amounts of such fluid can impair breathing by limiting the expansion of the lungs during ventilation.-Pathophysiology:...
. More commonly associated with excess fluid is pulmonary edema. - Fluid in the peritoneal cavityPeritoneal cavityThe peritoneal cavity is a potential space between the parietal peritoneum and visceral peritoneum, that is, the two membranes that separate the organs in the abdominal cavity from the abdominal wall...
causing ascitesAscitesAscites is a gastroenterological term for an accumulation of fluid in the peritoneal cavity.The medical condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy. Although most commonly due to cirrhosis and severe liver...
. - Generalized edema throughout the body known as anasarcaAnasarcaAnasarca, also known as "extreme generalized edema" is a medical condition characterised by widespread swelling of the skin due to effusion of fluid into the extracellular space....
.
- Most of the patients are normotensive but hypertensionHypertensionHypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
(rarely) may also occur. - AnemiaAnemiaAnemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...
(iron resistant microcytic hypochromic type) maybe present due to transferrin loss. - DyspneaDyspneaDyspnea , shortness of breath , or air hunger, is the subjective symptom of breathlessness.It is a normal symptom of heavy exertion but becomes pathological if it occurs in unexpected situations...
maybe present due to pleural effusionPleural effusionPleural effusion is excess fluid that accumulates between the two pleural layers, the fluid-filled space that surrounds the lungs. Excessive amounts of such fluid can impair breathing by limiting the expansion of the lungs during ventilation.-Pathophysiology:...
or due to diaphragmatic compression with ascites. - Erythrocyte sedimentation rateErythrocyte sedimentation rateThe erythrocyte sedimentation rate , also called a sedimentation rate or Biernacki Reaction, is the rate at which red blood cells sediment in a period of 1 hour...
is increased due to increased fibrinogen & other plasma contents. - Some patients may notice foamy or frothy urineUrineUrine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
, due to a lowering of the surface tensionSurface tensionSurface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...
by the severe proteinuriaProteinuriaProteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
. Actual urinary complaints such as hematuriaHematuriaIn medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
or oliguriaOliguriaOliguria is the low output of urine, It is clinically classified as an output below 300-500ml/day. The decreased output of urine may be a sign of dehydration, renal failure, hypovolemic shock, HHNS Hyperosmolar Hyperglycemic Nonketotic Syndrome, multiple organ dysfunction syndrome, urinary...
are uncommon, though these are seen commonly in nephritic syndromeNephritic syndromeNephritic syndrome is a collection of signs associated with disorders affecting the kidneys, more specifically glomerular disorders. It is characterized by having small pores in the podocytes of the glomerulus, large enough to permit proteins and red blood cells to pass into the urine...
. - May have features of the underlying cause, such as the rashRashA rash is a change of the skin which affects its color, appearance or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracked or blistered, swell and may be painful. The causes, and...
associated with systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
, or the neuropathy associated with diabetes. - Examination should also exclude other causes of gross edema—especially the cardiovascular and hepatic system.
Causes
Nephrotic syndrome has many causes and may either be the result of a disease limited to the kidney, called primary nephrotic syndrome, or a condition that affects the kidney and other parts of the body, called secondary nephrotic syndrome.Primary
Primary causes of nephrotic syndrome are usually described by the histologyHistology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
, i.e. minimal change disease
Minimal change disease
Minimal Change Disease is a disease of the kidney that causes nephrotic syndrome and usually affects children .-Epidemiology:...
(MCD) like minimal change nephropathy which is the most common cause of nephrotic syndrome in children, focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis is a cause of nephrotic syndrome in children and adolescents, as well as an important cause of kidney failure in adults.It is also known as "focal glomerular sclerosis" or "focal nodular glomerulosclerosis"....
(FSGS) and membranous nephropathy (MN) like membranous glomerulonephritis which is the main cause of nephrotic syndrome in adult.
They are considered to be "diagnoses of exclusion
Diagnosis of exclusion
A diagnosis of exclusion is a medical condition reached by a process of elimination, which may be necessary if presence cannot be established with complete confidence from examination or testing...
", i.e. they are diagnosed only after secondary causes have been excluded.
Secondary
Secondary causes of nephrotic syndrome have the same histologic patterns as the primary causes, though may exhibit some differences suggesting a secondary cause, such as inclusion bodiesInclusion bodies
Inclusion bodies are nuclear or cytoplasmic aggregates of stainable substances, usually proteins. They typically represent sites of viral multiplication in a bacterium or a eukaryotic cell and usually consist of viral capsid proteins...
.
They are usually described by the underlying cause.
Secondary causes by histologic pattern:
Membranous nephropathy (MN):
- Hepatitis B & Hepatitis C
- Sjögren's syndromeSjögren's syndromeSjögren's syndrome , also known as "Mikulicz disease" and "Sicca syndrome", is a systemic autoimmune disease in which immune cells attack and destroy the exocrine glands that produce tears and saliva....
- Systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
(SLE) - Diabetes mellitusDiabetes mellitusDiabetes mellitus, often simply referred to as diabetes, is a group of metabolic diseases in which a person has high blood sugar, either because the body does not produce enough insulin, or because cells do not respond to the insulin that is produced...
- SarcoidosisSarcoidosisSarcoidosis , also called sarcoid, Besnier-Boeck disease or Besnier-Boeck-Schaumann disease, is a disease in which abnormal collections of chronic inflammatory cells form as nodules in multiple organs. The cause of sarcoidosis is unknown...
- Drugs (such as corticosteroids, gold, intravenous heroin)
- Malignancy (cancer)
- Bacterial infections, e.g. leprosy & syphilis
- Protozoal infections, e.g. malaria
Focal segmental glomerulosclerosis (FSGS)
- Hypertensive nephrosclerosis
- HIV
- ObesityObesityObesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
- Kidney loss
Minimal change disease (MCD)
- Drugs, especially NSAIDs in the elderly
- Malignancy, especially Hodgkin's lymphomaHodgkin's lymphomaHodgkin's lymphoma, previously known as Hodgkin's disease, is a type of lymphoma, which is a cancer originating from white blood cells called lymphocytes...
- Leukemia
Allergy
- Bee sting
Diagnosis
The gold standard in diagnosis of nephrotic syndrome is 24 hour urine protein measurement. Aiding in diagnosis are blood tests and sometimes imaging of the kidneys (for structure and presence of two kidneys), and/or a biopsy of the kidneys.The following are baseline, essential investigations:
- 24 hour bedside urinary total protein estimation.
Urine sample shows proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
(>3.5 g per 1.73 m2 per 24 hours). It is also examined for urinary casts
Urinary casts
Urinary casts are cylindrical structures produced by the kidney and present in the urine in certain disease states. They form in the distal convoluted tubule and collecting ducts of nephrons, then dislodge and pass into the urine, where they can be detected by microscopy.They form via precipitation...
, which are more a feature of active nephritis.
- Comprehensive metabolic panel (CMP) shows hypoalbuminemiaHypoalbuminemiaHypoalbuminemia is a medical condition where levels of albumin in blood serum are abnormally low. It is a specific form of hypoproteinemia.Albumin is a major protein in the human body, making up about 60% of total human plasma protein by mass...
: albuminAlbuminAlbumin refers generally to any protein that is water soluble, which is moderately soluble in concentrated salt solutions, and experiences heat denaturation. They are commonly found in blood plasma, and are unique to other blood proteins in that they are not glycosylated...
level ≤2.5 g/dL (normal=3.5-5 g/dL). - Lipid profile.
High levels of cholesterol
Cholesterol
Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...
(hypercholesterolemia
Hypercholesterolemia
Hypercholesterolemia is the presence of high levels of cholesterol in the blood. It is not a disease but a metabolic derangement that can be caused by many diseases, notably cardiovascular disease...
), specifically elevated LDL
Low density lipoprotein
Low-density lipoprotein is one of the five major groups of lipoproteins, which in order of size, largest to smallest, are chylomicrons, VLDL, IDL, LDL, and HDL, that enable transport of cholesterol within the water-based bloodstream...
, usually with concomitantly elevated VLDL
Very low density lipoprotein
Very-low-density lipoprotein is a type of lipoprotein made by the liver. VLDL is one of the five major groups of lipoproteins that enable fats and cholesterol to move within the water-based solution of the bloodstream...
is typical.
- Electrolytes, ureaUreaUrea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
and creatinineCreatinineCreatinine is a break-down product of creatine phosphate in muscle, and is usually produced at a fairly constant rate by the body...
(EUCs): to evaluate renal function.
Further investigations are indicated if the cause is not clear:
- Biopsy of kidneyKidneyThe kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
(in case of adult patients only). - Auto-immune markers (ANAAnti-nuclear antibodyAnti-nuclear antibodies are autoantibodies directed against contents of the cell nucleus....
, ASOT, C3C3 (complement)Complement component 3, often simply called C3, is a protein of the immune system. It plays a central role in the complement system and contributes to innate immunity. In humans it is encoded on chromosome 19 by a gene called C3.-Function:...
, cryoglobulins, serum electrophoresisSerum protein electrophoresisSerum protein electrophoresis is a laboratory test that examines specific proteins in the blood called globulins. Blood must first be collected, usually into an airtight vial or syringe...
). - UltrasoundMedical ultrasonographyDiagnostic sonography is an ultrasound-based diagnostic imaging technique used for visualizing subcutaneous body structures including tendons, muscles, joints, vessels and internal organs for possible pathology or lesions...
of the whole abdomen.
Classification
A broad classification of nephrotic syndrome based on underlying cause:Nephrotic syndrome is often classified histologically:
Differential diagnosis
When someone presents with generalized edema, the following causes should be excluded:- Heart failure: The patient is older, with a history of heart disease. Jugular venous pressure is elevated on examination, might hear heart murmurs. An echocardiogram is the gold standard investigation.
- Liver failureLiver failureAcute liver failure is the appearance of severe complications rapidly after the first signs of liver disease , and indicates that the liver has sustained severe damage . The complications are hepatic encephalopathy and impaired protein synthesis...
: History suggestive of hepatitis/ cirrhosis: alcoholism, IV drug use, some hereditary causes.
Signs of liver disease are seen: jaundiceJaundiceJaundice is a yellowish pigmentation of the skin, the conjunctival membranes over the sclerae , and other mucous membranes caused by hyperbilirubinemia . This hyperbilirubinemia subsequently causes increased levels of bilirubin in the extracellular fluid...
(yellow skin and eyes), dilated veins over umbilicus (caput medusaeCaput medusaeCaput medusae is the appearance of distended and engorged paraumbilical veins, which are seen radiating from the umbilicus across the abdomen to join systemic veins...
), scratch marks (due to widespread itching, known as pruritus), enlarged spleen, spider angiomata, encephalopathy, bruising, nodular liver. - AcuteAcuteAcute may refer to:* Acute accent* Acute angle* Acute * Acute * Acute toxicity...
fluid overloadHypervolemiaHypervolemia, or fluid overload, is the medical condition where there is too much fluid in the blood.The opposite condition is hypovolemia, which is too little fluid volume in the blood.-Causes:Excessive sodium or fluid intake:* IV therapy...
in someone with kidney failure: These people are known to have kidney failure, and have either drunk too much or missed their dialysis. - Metastatic cancerMetastasisMetastasis, or metastatic disease , is the spread of a disease from one organ or part to another non-adjacent organ or part. It was previously thought that only malignant tumor cells and infections have the capacity to metastasize; however, this is being reconsidered due to new research...
: when cancer spreads to the lungs or abdomen it causes effusions and fluid accumulation due to obstruction of lymphatics and veins, as well as serous exudation.
Supportive
- Monitoring and maintaining euvolemia (the correct amount of fluid in the body):
- Monitoring urine output, BP regularly.
- Fluid restrict to 1 L.
- Diuretics (IV furosemide).
- Monitoring kidney function:
- do EUCs daily and calculating GFR.
- Treat hyperlipidemia to prevent further atherosclerosis.
- Prevent and treat any complications [see below]
- Albumin infusions are generally not used because their effect lasts only transiently.
Prophylactic anticoagulation may be appropriate in some circumstances.
Specific
- Immunosuppression for the glomerulonephritides (corticosteroidCorticosteroidCorticosteroids are a class of steroid hormones that are produced in the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte...
s, ciclosporinCiclosporinCiclosporin , cyclosporine , cyclosporin , or cyclosporin A is an immunosuppressant drug widely used in post-allogeneic organ transplant to reduce the activity of the immune system, and therefore the risk of organ rejection...
).
- Standard ISKDC regime for first episode: prednisolonePrednisolonePrednisolone is the active metabolite of prednisone, which is also used as a drug.-Uses:Prednisolone is a corticosteroid drug with predominant glucocorticoid and low mineralocorticoid activity, making it useful for the treatment of a wide range of inflammatory and auto-immune conditions such as...
-60 mg/m2/day in 3 divided doses for 4 weeks followed by 40 mg/m2/day in a single dose on every alternate day for 4 weeks.
- Relapses by prednisolone 2 mg/kg/day till urine becomes negative for protein. Then, 1.5 mg/kg/day for 4 weeks.
- Frequent relapses treated by: cyclophosphamideCyclophosphamideCyclophosphamide , also known as cytophosphane, is a nitrogen mustard alkylating agent, from the oxazophorines group....
or nitrogen mustard or ciclosporin or levamisoleLevamisoleLevamisole is an anthelminthic and immunomodulator belonging to a class of synthetic imidazothiazole derivatives. It was discovered at Janssen Pharmaceutica in 1966...
.
- Achieving better blood glucose level control if the patient is diabetic.
- Blood pressureBlood pressureBlood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
control. ACE inhibitors are the drug of choice. Independent of their blood pressure lowering effect, they have been shown to decrease protein loss.
Diet
Reduce sodium intake to 1000–2000 mg daily. Foods high in sodium include salt used in cooking and at the table, seasoning blends (garlic salt, Adobo, season salt, etc.) canned soups, canned vegetables containing salt, luncheon meats including turkey, ham, bologna, and salami, prepared foods, fast foods, soy sauce, ketchup, and salad dressings. On food labels, compare milligrams of sodium to calories per serving. Sodium should be less than or equal to calories per serving.Eat a moderate amount of high protein animal food: 3-5 oz per meal (preferably lean cuts of meat, fish, and poultry)
Avoid saturated fats such as butter, cheese, fried foods, fatty cuts of red meat, egg yolks, and poultry skin. Increase unsaturated fat intake, including olive oil, canola oil, peanut butter, avocadoes, fish and nuts. Eat low-fat desserts.
Increase intake of fruits and vegetables. No potassium or phosphorus restriction necessary.
Monitor fluid intake, which includes all fluids and foods that are liquid at room temperature. Fluid management in nephrotic syndrome is tenuous, especially during an acute flare.
Complications
- Venous thrombosisVenous thrombosisA venous thrombosis is a blood clot that forms within a vein. A venous thrombosis is a blood clot that forms within a vein. A venous thrombosis is a blood clot that forms within a vein. (Thrombosis is a medical term for blood clotting (Haemostasis) occurring in the wrong place, i.e...
: due to leak of anti-thrombin 3, which helps prevent thrombosis. This often occurs in the renal veins. Treatment is with oral anticoagulants (not heparin as heparin acts via anti-thrombin 3 which is lost in the proteinuria so it will be ineffective.) Hypercoagulopathy due to extravasation of fluid from the blood vessels (oedema) is also a risk for venous thrombosis.
- InfectionInfectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
: due to leakage of immunoglobulins, encapsulated bacteria such as Haemophilus influenzae and Streptococcus pneumoniae can cause infection.
- Acute renal failureAcute renal failureAcute kidney injury , previously called acute renal failure , is a rapid loss of kidney function. Its causes are numerous and include low blood volume from any cause, exposure to substances harmful to the kidney, and obstruction of the urinary tract...
is due to hypovolemiaHypovolemiaIn physiology and medicine, hypovolemia is a state of decreased blood volume; more specifically, decrease in volume of blood plasma...
. Despite the excess of fluid in the tissues, there is less fluid in the vasculature. Decreased blood flow to the kidneys causes them to shutdown. Thus it is a tricky task to get rid of excess fluid in the body while maintaining circulatory euvolemia.
- Pulmonary edemaPulmonary edemaPulmonary edema , or oedema , is fluid accumulation in the air spaces and parenchyma of the lungs. It leads to impaired gas exchange and may cause respiratory failure...
: again due to fluid leak, sometimes it leaks into lungs causing hypoxiaHypoxia (medical)Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise...
and dyspnoea.
- Growth retardation: does not occur in MCNS.It occurs in cases of relapses or resistance to therapy. Causes of growth retardation are protein deficiency from the loss of protein in urine, anorexiaAnorexia (symptom)Anorexia is the decreased sensation of appetite...
(reduced protein intake), and steroid therapy (catabolism).
- Vitamin D deficiency can occur. Vitamin D binding protein is lost.
- HypothyroidismHypothyroidismHypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone.Iodine deficiency is the most common cause of hypothyroidism worldwide but it can be caused by other causes such as several conditions of the thyroid gland or, less commonly, the pituitary gland or...
can occur. Thyroxine is reduced due to decreased thyroid binding globulin.
- Microcytic hypochromic anaemia is typical. It is iron-therapy resistant.
- Hypocalcemia can occur as a result of nephrotic syndrome. It may be significant enough to cause tetanyTetanyTetany has two meanings, though both are related to the muscular system.* Tetany * Tetany The terms "tetany" and "tetanus" are distinct....
. Hypocalcemia may be relative; calcium levels should be adjusted based on the albumin level and ionized calcium should be checked.
- Cushing's SyndromeCushing's syndromeCushing's syndrome is a hormone disorder caused by high levels of cortisol in the blood. This can be caused by taking glucocorticoid drugs, or by tumors that produce cortisol or adrenocorticotropic hormone or CRH...
Prognosis
The prognosis depends on the cause of nephrotic syndrome. It is usually good in children, because minimal change diseaseMinimal change disease
Minimal Change Disease is a disease of the kidney that causes nephrotic syndrome and usually affects children .-Epidemiology:...
responds very well to steroids and does not cause chronic renal failure
Chronic renal failure
Chronic kidney disease , also known as chronic renal disease, is a progressive loss in renal function over a period of months or years. The symptoms of worsening kidney function are unspecific, and might include feeling generally unwell and experiencing a reduced appetite...
. However other causes such as focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis is a cause of nephrotic syndrome in children and adolescents, as well as an important cause of kidney failure in adults.It is also known as "focal glomerular sclerosis" or "focal nodular glomerulosclerosis"....
frequently lead to end stage renal disease
End stage renal disease
End stage renal disease may refer to:* End-stage renal disease, also known as chronic kidney disease , specifically the fifth stage of CKD...
. Factors associated with a poorer prognosis in these cases include level of proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
, blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
control and kidney function (GFR).
External links
- NephCure Foundation currently the only organization committed exclusively to support research seeking the cause of Nephrotic Syndrome and FSGS, improve treatment and find a cure
- Kidcomm a resource for parents of Children with nephrotic syndrome and other kidney diseases
- Nephrotic Syndrome Research A team of kidney doctors and scientists from Beth Israel Deaconess Medical Center / Harvard Medical School working to learn more about the cause of Nephrotic Syndrome in children and adults, with an emphasis on the genetic basis of this disease.
- Nutrition Care Manual from the American Dietetic AssociationAmerican Dietetic AssociationThe American Dietetic Association is the United States' largest organization of food and nutrition professionals, with nearly 72,000 members. The American Dietetic Association is officially changing its name to the Academy of Nutrition and Dietetics. The announcement was made Saturday, September...
- Information from the NephCure Foundation
- Childhood Nephrotic Syndrome - National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH
- Adult Nephrotic Syndrome - National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH