What is Proteinuria?Proteinuria is the most common urinary abnormalities, it is defined by the presence of protein in the urine (proteinuria) at a rate greater than 150 mg (0.15 g) in 24 hours.
Proteinuria can be detected at the dipstick when the rate is> 300 mg / l and must be confirmed by a laboratory quantitation (proteinuria of 24).
Proteinuria is always pathological, except in one situation where the normal proteinuria 300mg/24: pregnancy.
Proteinuria is an analysis that is done on the urine of 24 hours.
Note: The dipstick only detects albumin from all other proteins that may exist in the urine.
Assay of proteinuria and urine collection.
The urine collection:
empty the bladder in the morning at 08 am without collecting the urine.
collect all the urine (even those of the night) until the next 08h,
Interest of the determination of proteinuria.
Proteinuria of 24 hours in a quantitative and qualitative interest:
Quantitative study: dosing of 24h (24h urine collection), there is a physiological proteinuria of 50-150 mg/24 h, when proteinuria is> 150mg/24 h is a pathological proteinuria.
Qualitative study: urinary protein electrophoresis of 24 is used to find the selectivity of proteinuria and detection of multiple myeloma.
Selectivity of proteinuria.
Selective proteinuria> 80% albumin, purity criteria of nephrotic syndrome.
Non-selective proteinuria <80% albumin, test impure nephrotic syndrome.
Circumstances of discovery of proteinuria
Proteinuria can be discovered in of exploring an edematous syndrome, screening with a dipstick,
record of hypertension or systemic disease, monitoring of pregnancy.
The main situations in which proteinuria increases.
the main situations in which proteinuria increases are:
1. Intermittent proteinuria
It proteinuria that occurs and disappears after the disappearance of the cause can be:
febrile illnesses in children,
2. Proteinuria contemporary a urinary tract infection
3. Orthostatic proteinuria
encountered in children and young adults,
may be abundant, but without clinical signs
confirmed by measurement of urine collected in strict supine for several hours (disappearance of proteinuria).
4. Proteinuria and hypertension
Hypertension old: nephro-angiosclérose
pregnant women: pre-eclampsia
5. The nephrotic syndrome post-infective
Kidney due to infection
6. Nephrotic syndrome
7. Other causes of proteinuria
There are other situations where one can find an increased proteinuria:
Urinary tract infection,
the general glomerular diseases (eg systemic diseases)
chronic interstitial nephropathy
8. Special case: proteinuria of multiple myeloma.
Proteinuria is abundant, not detected by the dipstick because the proteins other than albumin, protein electrophoresis gives a spike in multiple myeloma.
In conclusion, proteinuria should be taken as a symptom and not a disease in itself: it is not to treat the proteinuria but to seek and address the causes that led to the installation of this urinary abnormality.