Albuminuria or “protein in urine” – the identical term “proteinuria”. Apparently, equality is due to the fact that among the protein composition of the blood albumin accounts for 80%. This suggests that the transition of this fraction in urine provides losses and impairment of body functions.
In the urine of a healthy person can be detected “trace protein” or 0,033 g/l. This conclusion is not serious but requires supervision. There are physiological causes of proteinuria.
It is known that protein molecules have large dimensions, so normally do not pass through the membrane of the glomerular apparatus of the kidneys. The elucidation of the causes of albuminuria helps to set the affected on and promptly appoint treatment.
As protein enters the urine in a healthy person?
It is established that the maximum amount of protein in the urine of a healthy person per day is up to 50 mg. per serving it may not be. More precisely, the paltry amount is not determined by the usual methods. For children rate believe per m2 body surface: for kids to month, the rate should not exceed 240 mg, older – 60 mg per day.
In addition, proteins contained in the cellular elements (leukocytes, erythrocytes, epithelium of the tubules). Excessive alkalinisation of the urine to a hearty meal there is a partial disintegration of the cells and the transition contained therein protein in urine. This contributes to the increase in pressure causes the arteries, accelerating the filtration process.
Violation bandwidth renal membrane for albumin fraction of proteins, since they have the smallest size of molecules and in case of overload
filtering is able to penetrate through the pores
Do I need to reckon with a temporary physiological albuminuria?
Physiological albuminuria is observed temporarily, refers to a transient (transient) forms.
- after heavy physical exertion (athletes during the competition);
- by eating rich food, containing meat products, raw eggs, raw milk;
- in infants when overfed (in 92% of newborns);
- in women by pregnancy.
In these cases, the amount of protein in daily urine can reach up to 1 g, but disappears on its own, not accompanied by any symptoms of kidney damage, the appearance of the vehicle and hematuria.
During pregnancy is considered to be:
- less than 30 mg/day. – the norm;
- from 30 to 300 mg microalbuminuria;
- in excess of 300 mg (according to other authors the boundary 500 mg) – macroalbuminuria.
To the study of albuminuria during pregnancy are very carefully, because exceeding the rate may be a sign of pre-eclampsia.
There are different types of functional albuminuria.
They are connected:
- with increasing temperature, fever acute infectious disease, without inflammation of the urinary organs;
- emotional stress, strain;
- a sudden change of body position (when lifting from horizontal to vertical) or enforced idleness, called orthostatic proteinuria, which is typical for children, adolescents and young people up to 30 years, during the day, it is possible to allocate up to 10 grams of protein;
- dehydration in the heat without adequate drinking;
- allergic reactions;
Young children stand out:
- dehydration proteinuria – occurs with persistent diarrhea, vomiting, violation of drinking regime;
- stroke albuminuria is associated with increased irritability of the kidneys in response to bathing in cold water, overfeeding, palpation of the kidneys, physical fatigue, fear.
Bathe children even in the heat you need in warm water
If caused factors cannot be established, the albuminuria considered idiopathic.
Why there albuminuria in pathology?
Pathological proteinuria 2 contribute to the mechanism of violations:
- The glomerulus (glomerular) – represented by the enhanced permeability of the basal membrane. Through extended passages caused by diseases in the primary urine to penetrate small and large molecule proteins.
- Tubular (tubular) – occurs when the normal basement membrane. Through it passes urine in the primary a small number of proteins. Once in the tubular apparatus, they accumulate, since it is not provided by the process of reabsorption.
Molecules of albumin so much that kanalzeva apparatus, despite its safety, does not occur to reverse the suction and return them to the blood.
These mechanisms are involved in the pathogenesis of various kidney diseases. The greatest diagnostic importance of proteinuria in identifying and selecting a method of treatment of patients with the formation of chronic renal failure.
Causes and types of pathological albuminuria
For pathological albuminuria characterized by a higher content of protein in daily urine, presence of signs such as leukocytes, erythrocytes, cylinders, bacteria, salts, cells of renal epithelium in the sediment.
- renal albuminuria.
About proteinuria (extrarenal) is a source of protein here are:
- admixture of inflammatory reactions in diseases of the digestive organs;
- destroyed red blood cells in anemia;
- massive burn surface;
- injury crush and tear the muscle tissue;
- hypothermia and frostbite.
In urological practice, the largest number of observations accounts for cases with hematuria of various origins. True (kidney) proteinuria is always accompanied by inflammation and breakdown of tissues of the kidneys, affects the basal membrane and increases its permeability to protein molecules.
Such a mechanism is typical for albuminuria:
- in glomerulonephritis;
- amyloidosis of the kidneys;
- the nephrosclerosis;
- nephropathy pregnant women;
- disorders of the renal circulation;
- the toxic action of toxic substances and some medications.
Glomerulonephritis – pathology, which occurs albuminuria
What you need to investigate the protein in the urine of chronic renal patients?
Mechanisms of proteinuria in the end destroy the system of regulation of renal function and lead to the development of chronic renal failure. In ICD-10 the term was changed to “chronic kidney disease” code N18 (CKD).
In the diagnosis of patients with CKD is to be applied to the study of the proteins of blood and urine. To assess the extent of destruction carried out calculation of the coefficient of albumin/creatinine in a single morning serving. At the same time explore the glomerular filtration rate.
- to confirm the diagnosis or to reject him;
- to predict the course of the disease;
- to establish the risk of lesion of the cardiovascular system;
- choose the right the best treatment.
During latent, the absence of clinical manifestations is the only reliable sign of kidney damage, it is called “a marker of renal dysfunction”.
The value of the coefficient shows pathophysiological disturbances in the kidneys:
- increased permeability of cell membranes;
- change of transport of bioactive substances at the level of proximal tubules;
- increased pressure and burden on the glomerular apparatus;
- dysfunction of endothelial cells.
The form and stage of
For ease of diagnostics at an international conference in London in 2009 and developed stage of albuminuria.
The severity of albuminuria is considered to be for the amount of protein per gram of creatinine in urine:
- I – less than 30;
- II – 30 to 299;
- III – more than 300 mg/g.
In addition, there was a proposal to consider this indicator as a reflection of the level of excretion in the cells of the tubular epithelium:
- optimal is less than 10 mg/g;
- exceeding the limit – from 10 to 29;
- high – from 30 to 299;
- very high – from 300 to 1999;
- nephrotic – more than 2000.
In the last two stages of protein loss in the urine is up to 3.5 g per day.
Determination of protein included in the standard urine analysis
For full features of chronic renal failure must take into account the degree of decrease in glomerular filtration rate. In the terminal stage it is less than 15 ml/min. the diagnosis must indicate the stage of CKD and albuminuria index.
Some authors adhere to the old classification of albuminuria with the division:
- normoalbuminuria in the urine contains proteins up to 17 mg/l;
- microalbuminuria – 17 to 173 mg/l;
- macroalbuminuria – more than 173 mg/l.
Accounting albuminuria helps to choose the type of replacement therapy (hemodialysis or kidney transplantation).
What laboratory methods are used to detect protein in urine?
All methods are divided into:
- on quality;
- semi-quantitative on the basis of the color change of test strips is set to a certain period on a scale of albuminuria;
Qualitative tests to detect the proteins. But it is impossible to identify their true content. Therefore, they are carried out during the examination of a significant contingent of the medical examinations. Patient with a positive test called for re-investigation and further quantitative analysis. Proposed over 100 techniques. Their essence: effects on proteins in the urine with chemical reagents or by heating to the appearance of the precipitate in the form of turbidity.
Clinics tests are used :
- sulfosalicylic acid;
Is ring sample Geller with 30% nitric acid
Conclusion look like:
- “the test for protein is negative”;
- “weakly positive”;
- “dramatically positive”.
Quantitative methods allow you to accurately set the size of the loss of protein in the urine. On prescription are from a single morning serving or initially collected daily urine. The most common colorimetric method, which assesses the degree of turbidity in comparison with the control solution.
What are the symptoms one can suspect the albuminuria?
It should be recalled that albuminuria is not a separate disease. This in itself is a sign of functional or pathological changes.
Renal proteinuria are possible following clinical manifestations:
- severe weakness and fatigue;
- headaches and dizziness;
- pain in bones and joints;
- swelling of the face, legs and feet;
- temperature rise;
- low urine output;
- possible chills;
- poor appetite;
- nausea and vomiting;
- pain in the lumbar region of different intensity;
- frequent urination with sharp pains;
- pain in the abdomen;
- discoloration of urine is whitish in color, hematuria redness.
If albuminuria develops in diseases of the heart, the patient feels:
- chest pain radiating to the left in the blades;
- on the background of the headaches increased blood pressure;
- shortness of breath when moving or at rest.
Special treatment against albuminuria does not exist. And diseases are treated taking into account pathogenetic mechanisms of lesions. The disappearance or decrease in the level of protein in the urine is an indicator of effective treatment, and in CKD – achieve remission.
In different inflammatory diseases of the kidney are used:
- a restrictive diet with reduction of irritating substances, salts, proteins, fats;
- mandatory bed rest and hospitalization during the acute period;
- antibiotics, non-nephrotoxic effects;
- removal of intoxication with the introduction of Gemodez;
- the introduction of the alkaline solution to relieve increased acidity;
- Reopoligljukin and vasodilators for the correction of renal blood flow;
- cytostatics in the case of autoimmune mechanisms;
- ACE inhibitors;
- blockers angiotensin–II.
In the treatment of chronic renal failure is a hardware hemodialysis, plasmapheresis, peritoneal dialysis. The most effective treatment is kidney transplantation. It is difficult to overestimate the importance of the study of albuminuria in a patient. In the practice of medicine without it can not do in the diagnosis, difficult to find harmless treatment. Patients and doctors expect a normalization of rate, as witness the effectiveness of therapy.