3. Overview
Normal or Physiological Urinary Protein Excretion.
Definition.
Pathological Proteinuria(Types & Causes).
Evaluation.
Detection & Measurement.
Management.
Prognosis.
Take Home Messages.
4. Normal Urinary Protein Excretion
Normally,Urinary Protein Excretion is less than 150 mg/day in adults.
It is usually not detected by ordinary methods.
It is composed of :
1.Tamm-Horsfall Glycoprotein-50%
2.Albumin- 20%
3.Immunoglobulin-5%
4.Others- Small Amounts of Hormones and Enzymes &
Blood Group related substances
Davidson 24th Edition+PubMed
5. Definition
Proteinuria: Urinary protein excretion >150mg/24 hr.
Albuminuria: Urinary albumin excretion >30mg/24 hr.
Micro-Albuminuria: Persistent albumin excretion between 30 to 300 mg/24hr is
called moderately increased albuminuria(Formerly called microalbuminuria).
Macro-Albuminuria : Albumin excretion above 300mg/24 hr is considered Overt
Proteinuria or Macroalbuminuria(Dipstick-positive).
Davidson 24th Edition
6. Benign or Transient Proteinuria
Transient proteinuria is the temporary excretion of protein.
Most common form of proteinuria.
Usually resolves without treatment.
Causes:
1.Fever
2.After vigorous Exercise.
3.Extreme cold.
4.Seizures
5.CCF.
6.Severe Acute illness.
7.UTI.
UP TO DATE
7. Postural(Orthostatic)Proteinuria
When one loses protein in the urine while in upright position but not when
lying down.
Excrete less than 1g/24hrs of protein.
Benign disorder that does not require treatment.
UP TO DATE
8. Persistent Proteinuria
In contrast to transient and orthostatic proteinuria,Persistent proteinuria occurs
in people with underlying Kidney diseases or other medical problems.Examples
incude:
1.Kidney Diseases.
2.Diseases that affect the kidney,such as DM and High Blood pressure.
3.Diseases that cause the body to overproduce certain types of protein.
UP TO DATE
11. Evalution of the patient with Proteinuria
History
Onset: Acute/Chronic,On basis of duration.
Diabetic history if applicable(Specially H/O retinopathy/neuropathy)
Renal symptoms: Oedema,HTN,Haematuria,Foamy Urine.
Constitutional symptoms: Fever,nausea,appetite,wt change.
Symptoms of coagulopathy: DVT,Pulmonary Embolism.
Rheumatological history.
Malignancy.
Family history of renal disease.
Exposure to toxins.
12. Cont…..
Physical Examination
General Examination: BP and weight,Oedema,rashes.
Systemic Examinations including Cardiopulmonary and musculoskeletal system.
Fundoscopic examination.
13. Continued
Lab Investigations
Required: Urine R/E, 24 hr Urinary total protein or spot urine for Protein/creatinine ratio(PCR),
Albumin/Creatinine ratio(ACR), Urine Dipstick Test.
As Clinically indicated: Fasting lipid profile, HbA1c, ANA, C3,C4, HBsAg, AntiHCV.
Opthalmological examination,Renal Ultra sound.
Renal Biopsy as Indicated.
14. Detection & Measurement of Total Urinary Protein Excretion
Semiquantitative Measurement
Standard Urine Dipstick: The standard urine dipstick primarily detects albumin but is relatively insensitive to non-albumin
proteins.Thus,a positive dipstick usually reflects glomerular proteinuria.
Sulfosalicylc Acid Test: In contrast to the urine dipstick, which primarily detects all proteins in the urine at a sensitivity of 5 to 10
mg/dl.Use of SSA is primarily indicated in patients who present with-
1. Acute kidney Injury.
2. A Benign Urinalysis.
3. A negative or trace dipstick
4. A setting in which myeloma kidney should be excluded.
15. Sulfosalicylic Acid Test
Negative : No cloudiness
Trace: Faint turbidity.
1+ : definite turbidity
2+ : Heavy turbidity but no flocculation
3+ : Heavy turbidity with light flocculation.
4+ : Heavy turbidity with heavy flocculation.
16. Continue
Quantitative measurement
Determination of degree of protein excretion is a central part of the evaluation of patients with acute and chronic kidney diseases and in
patients incidentally noted to have persistent proteinuria by semiquantitative method.
24 hr Urine Protein.
Protein Creatinine ratio.
Albumin Creatinine ratio.
19. Urine Microscopic Analysis
When proteinuria is found on Dipstick analysis, the urinary sediment should be examined microscopically
for:
Fatty casts , Free fat or Oval fat bodies Nephrotic range proteinuria(>3.5g/24hrs)
Leukocytes , leukocyte casts with bacteria UTI
Leukocytes, leukocyte casts without bacteria Renal Interstitial Diseases
Red Cell Casts , Dysmorphic Erythrocytes Glomerular Disease
Waxy , Granular or Cellular casts Advanced chronic renal disease
Eosinophiluria Drug-induced AIN
Hyaline casts No renal Diseases, present with Dehydration.
Davidson 24th Edition + UP TO DATE
20. Management
Blood Pressure Control
Diabetics: Control of BP shown to slow progression of nephropathy in several studies.
Non-Diabetics: BP control to MAP < 92 vs 107 with less progression of diseases .
Benefit greatest in nephrotic patients.
ACEI and ARB are the first line drugs.
Some meta analysis shows that non-dihydropiridine Ca channel blockers have anti
proteinuric effect.
21. Management(Cont…..)
Non-Specific Treatment
BP Control:<130/80 for both nondiabetics & Diabetics.
Lipid Control:Tchol <200,LDL <100 with HMG Co-A reductase inhabitors.
Glycemic control for diabetics: HbA1c <6.5%
Moderate dietary protein restriction: 0.8mg/kg/day +urine protein loses,careful
monitoring of nutritional status.
Edema:Diuretics,Sodium restriction.
Specific immunosuppressive therapies for primary glomerular diseases as indicated.
22. Prognosis
Diabetic nephropathy : Progression to ESRD over 10-20 yrs
after onset of proteinuria.
Nephrotic Syndrome: Variable but poorer overall prognosis.
23. Take Home Message
Proteinuria is not a specific diseases.
A systemic approach to the patient with proteinuria will
allow the clinician to efficiently distinguish between
benign and pathological causes.
