Proteinuria: Difference between revisions
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(Expanded with concise EM-focused content: when to evaluate in ED, transient vs pathologic causes, preeclampsia association, disposition) |
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==Background== | ==Background== | ||
*Normal protein excretion 150mg/24 hours | *Normal protein excretion <150mg/24 hours | ||
*>3.5g/24h | *>3.5g/24h is nephrotic range | ||
*Dipstick: more sensitive to albumin, less sensitive to Bence-Jones protein and globulins | *Dipstick: more sensitive to albumin, less sensitive to Bence-Jones protein and globulins | ||
**"Trace" protein | **"Trace" protein on dipstick is approximately normal | ||
*Key EM role: identify proteinuria associated with emergent conditions ([[preeclampsia]], [[nephrotic syndrome]], [[glomerulonephritis]]) | |||
*Incidental proteinuria on UA often requires outpatient follow-up, not ED workup | |||
==Differential Diagnosis== | |||
===Transient/Functional (Benign)=== | |||
*[[Fever]], acute illness, strenuous exercise, orthostatic proteinuria | |||
*[[Dehydration]], cold exposure | |||
*Usually resolves when precipitant corrected — no further workup needed in ED | |||
===Renal=== | ===Renal=== | ||
* | *'''[[Glomerulonephritis]]''': hematuria + proteinuria + RBC casts | ||
*'''[[Nephrotic syndrome]]''': massive proteinuria, hypoalbuminemia, edema, hyperlipidemia | |||
*'''Diabetic nephropathy''': most common cause of chronic proteinuria | |||
*[[Pyelonephritis]] | *Tubular dysfunction, [[IgA nephropathy]], membranous nephropathy | ||
*[[Pyelonephritis]], [[malignant hypertension]] | |||
=== | ===Pregnancy-Related=== | ||
*[[ | *'''[[Preeclampsia]]''' / [[eclampsia]] / [[HELLP]]: proteinuria + hypertension after 20 weeks | ||
*[[Acute fatty liver of pregnancy]] | |||
*[[ | |||
===Other=== | ===Other=== | ||
*[[ | *[[CHF]], [[shock]] (functional/prerenal) | ||
*[[ | *Drug-induced: [[NSAIDs]], [[aminoglycosides]], [[amphotericin]], [[penicillamine]] | ||
*Multiple myeloma (Bence-Jones protein — may be missed by dipstick) | |||
* | ==Evaluation== | ||
*[[ | ===When to Evaluate in ED=== | ||
*[[ | *Pregnant patient with proteinuria → check BP, labs for preeclampsia | ||
* | *Proteinuria + hematuria + RBC casts → glomerulonephritis workup | ||
* | *Proteinuria + severe edema → nephrotic syndrome workup | ||
== | *Isolated trace/1+ proteinuria without above features → outpatient follow-up | ||
* | |||
* | ===Workup=== | ||
* | *[[BMP]]: creatinine, albumin | ||
* | *[[CBC]] | ||
*Urine protein-to-creatinine ratio (spot urine — correlates with 24h protein) | |||
*Urine microscopy: RBC casts (GN), oval fat bodies (nephrotic syndrome) | |||
*If preeclampsia: LFTs, uric acid, LDH, platelet count | |||
==Management== | |||
*Treat underlying cause | |||
*Preeclampsia: [[magnesium sulfate]], antihypertensives, OB consultation | |||
*Nephrotic syndrome: diuretics for edema, nephrology referral | |||
*Most isolated proteinuria: outpatient nephrology follow-up | |||
==Disposition== | |||
*Admit: preeclampsia/eclampsia, acute GN with renal failure, severe nephrotic syndrome | |||
*Discharge: incidental proteinuria with normal renal function — arrange outpatient repeat UA and nephrology referral | |||
==See Also== | ==See Also== | ||
*[[ | *[[Glomerulonephritis]] | ||
*[[Nephrotic syndrome]] | |||
*[[Preeclampsia]] | |||
*[[Hematuria]] | |||
==References== | |||
<references/> | |||
[[Category:Renal]] | [[Category:Renal]] | ||
[[Category:Symptoms]] | [[Category:Symptoms]] | ||
Latest revision as of 00:41, 21 March 2026
Background
- Normal protein excretion <150mg/24 hours
- >3.5g/24h is nephrotic range
- Dipstick: more sensitive to albumin, less sensitive to Bence-Jones protein and globulins
- "Trace" protein on dipstick is approximately normal
- Key EM role: identify proteinuria associated with emergent conditions (preeclampsia, nephrotic syndrome, glomerulonephritis)
- Incidental proteinuria on UA often requires outpatient follow-up, not ED workup
Differential Diagnosis
Transient/Functional (Benign)
- Fever, acute illness, strenuous exercise, orthostatic proteinuria
- Dehydration, cold exposure
- Usually resolves when precipitant corrected — no further workup needed in ED
Renal
- Glomerulonephritis: hematuria + proteinuria + RBC casts
- Nephrotic syndrome: massive proteinuria, hypoalbuminemia, edema, hyperlipidemia
- Diabetic nephropathy: most common cause of chronic proteinuria
- Tubular dysfunction, IgA nephropathy, membranous nephropathy
- Pyelonephritis, malignant hypertension
Pregnancy-Related
- Preeclampsia / eclampsia / HELLP: proteinuria + hypertension after 20 weeks
- Acute fatty liver of pregnancy
Other
- CHF, shock (functional/prerenal)
- Drug-induced: NSAIDs, aminoglycosides, amphotericin, penicillamine
- Multiple myeloma (Bence-Jones protein — may be missed by dipstick)
Evaluation
When to Evaluate in ED
- Pregnant patient with proteinuria → check BP, labs for preeclampsia
- Proteinuria + hematuria + RBC casts → glomerulonephritis workup
- Proteinuria + severe edema → nephrotic syndrome workup
- Isolated trace/1+ proteinuria without above features → outpatient follow-up
Workup
- BMP: creatinine, albumin
- CBC
- Urine protein-to-creatinine ratio (spot urine — correlates with 24h protein)
- Urine microscopy: RBC casts (GN), oval fat bodies (nephrotic syndrome)
- If preeclampsia: LFTs, uric acid, LDH, platelet count
Management
- Treat underlying cause
- Preeclampsia: magnesium sulfate, antihypertensives, OB consultation
- Nephrotic syndrome: diuretics for edema, nephrology referral
- Most isolated proteinuria: outpatient nephrology follow-up
Disposition
- Admit: preeclampsia/eclampsia, acute GN with renal failure, severe nephrotic syndrome
- Discharge: incidental proteinuria with normal renal function — arrange outpatient repeat UA and nephrology referral
