Nephrotic Syndrome Pearl of the Day

Nephrotic Syndrome

Pathophysiology

Think about it like this: Glomerular basement membrane problem, you spill all your protein (albumin) from your plasma into your urine, leading to high urine protein, low serum protein, and edema. It may help to simply think of it as decreased oncotic pressure causing movement of fluid from the intravascular space to the interstitial space; in reality the pathophysiology of edema in nephrotic syndrome is a little more complicated - has to do with a combination of primary (due to renal disease) and secondary (via RAS pathway) sodium retention.

Thus,

nephrotic syndrome is defined by:

1. Heavy proteinuria

(protein excretion > 3.5 g/24 hours; UPEE>3.5; >2 in children)

2. Hypoalbuminemia

(< 3 g/dL; <2.5 in children)

3. Peripheral edema

(Hyperlipidemia and thrombotic disease are frequently observed with nephrotic syndrome but not required for the diagnosis, may also be immunosuppressed)

(UA should have no significant hematuria, casts, or RBCs which would suggest a nephritic picture)

Measuring Proteinuria 

The most convenient way is to calculate a 

Urinary Protein Excretion Estimation (UPEE)

(insert infantile bathroom humor here)

UPEE (g/day) = (urine protein (mg/dL)) / (urine creatinine (mg/dL))

This works because a random urine protein to urine creatinine ratio very closely approximates the true 24 hour urine protein excretion, as shown below.

Interpretation:

UPEE <2.0 g/day —> Within normal limits

UPEE 2.0–3.5 g/day —> Above normal limit - investigate further

UPEE >3.5 g/day —>Nephrotic range

Nephrotic vs Nephritic

Remember to always think of nephrotic syndrome in contrast to nephritic syndrome! I love this image:

Workup

1.

Make the diagnosis: urinalysis, urine protein, urine creatinine, serum albumin, a lipid panel, basic metabolic panel

2. Consider further testing to differentiate primary vs secondary on a case-by-case basis: HIV, ANA, complement (C3/C4 and total hemolytic complement), serum free light chains and urine protein electrophoresis and immunofixation, syphilis serology, hepatitis B and hepatitis C serologies, and the measurement of cryoglobulins; when in doubt, run it by nephrology

3. Consider testing for complications: POCUS for pleural effusion/ascites; CXR for pleural effusion, dopplers or CTA for venous thromboembolism; antithrombin III, plasminogen, protein S (hyper coagulability); immunoglobulins; 

3. Usually renal biopsy is required for definitive diagnosis

Etiology/Treatment/Dispo

In children 10 years or younger, it is minimal change disease (MCD) 90% of the time. Most MCD responds to corticosteroids.

In children >10 years, it is MCD >50% of the time.

In adults focal segmental glomerulosclerosis (FSGS) is the most common etiology (35%). It can be primary/idiopathic, or associated with other disease processes, most commonly HIV or massive obesity.

In most cases, a biopsy will be needed in order to confirm diagnosis.

Admit patients with severe edema, pulmonary effusions or respiratory symptoms, or signs and symptoms suggestive of systemic infection or thrombotic complications to the hospital.

Discharge with nephrology follow up ASAP and low salt diet if only mild-moderate edema.

In kids age 1-10, may consider starting a course of steroids (

Prednisone 2 mg/kg/day x 6 wks then 1.5 mg/kg every other day x 6 wks) only if:

• Age 1-10

• No renal insuficiency

• No macroscopic hematuria

• No sx systemic disease

• No HTN

• Normal C3 levels

Special scenarios

Nephrotic syndrome + chest pain?

DDX: PE and myocardial ischemia because hyperthrombotic, pneumonia (immunosuppressed), pleural effusion

Consider POCUS, CXR, CTA, EKG, cardiac enzymes

Severe edema:

Requires lasix

May need albumin infusion prior to lasix if anasarca or signs of intravascular depletion

Hopefully you’ve already consulted ICU if you’re having to do this

Significant hypertension:

ACEi or ARB

SBP/Empyema:

Pleural effusions/ascites are common in severe fluid overload

Both are extra susceptible to infection in this state

Low threshold for diagnostic paracentesis/thoracentesis

References

Uptodate: Overview of heavy proteinuria and the nephrotic syndrome

Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e: Chapter 134: Renal Emergencies in Children

Michael Mojica, MD. “PEM Guides.” NYU Langone Medical Center, 2015. iBooks. 

https://itunes.apple.com/us/book/pem-guides/id1039923332?mt=11

Google Image Search

Hemoptysis Pearl

Let’s Talk Hemoptysis

So your patient thinks they’re coughing up blood...

Initial questions:

• Are they actually coughing up blood?

• Or are they having hematemesis?

• Or epistaxis?

Seems like they actually are. So what could they have? What should you ask in your history?

• Infectious/inflammatory causes are very common:

  • Acute bronchitis - if you cough enough, you will get some inflammation of your airways and BOOM, hemoptysis)

  • COPD can cause neoangiogenesis to enhance alveolar blood delivery, new fragile blood vessels can rupture

  • In immunosuppressed patients, consider aspergillus and of course TB causing necrotic badness, thus also ask travel history

  • Lung parasites! paragonimiasis, echinococcus, schistosomiasis - ask about travel

  • Neoplastic

    • Bronchogenic carcinoma, bronchial adenoma, squamous cell carcinoma — ask about weight loss and constitutional sx, but know that tumors can also cause massive hemoptysis

    • Structural

      • Aortobronchial fistula — good point, if their giant thoracic aortic aneurysm eroded into one of their bronchi, they would be in extremis to say the least and you wouldn’t be taking this detailed history…

      • Tracheo-innominate fistula — usually 3d-6w after tracheostomy placement, life-threatening and scary, we’ll save management of TIF for another POD

      • Other chronic lung diseases leading to bronchiectasis —> chronic inflammation —>destruction of cartellagenous support —> ruptured blood vessels

      • Vasculitides and collagen-vascular diseases

        • Goodpastures - remember this? Me neither. Autoimmune disease where antibodies attack the basement membrane of the kidneys and lungs — so if known renal failure or hematuria + hemoptysis, think about this

        • Granulomatosis with polyangiitis, SLE, and Behçet’s can all do similar things — h/o autoimmune disorders, family history…

        • Cardiovascular

          • PE can cause a pulmonary infarction —> ischemia/necrosis of lung tissue—> bleeding — ask about PE risk factors!

          • Pulmonary hypertension — ?CHF ?mitral stenosis

OK, enough of that. Let’s break down management.

Are they bleeding a lot? Coughing up large amounts of copious bright red frothy blood in front of you and in respiratory distress? 

Massive Hemoptysis

They need

airway management (often emergent intubation), STAT labs/portable CXR, bronchoscopy, CT surgery/IR/ICU consults, CT scan if stable enough

. Also,

position them on their side with the bleeding lung down

so that gravity doesn’t wash all the blood into their ventilated lung. I like this algorithm from Tinti’s below. The only confusing acronyms are MDCT (multidetector computed tomography) and BAE (bronchial artery embolization).

You may be able to intubate the healthy mainstream

as shown below in order to protect the side you’re able to ventilate. As another option pulmonology/IR may help with placement of a Fogarty catheter to tamponade the bleeding side.

If it’s

mild hemoptysis

, think about whether quarantine and TB workup is needed. If not, they most likely have bronchitis, and may only need a CXR, but refer to this simpler algorithm to tell you when you need a little more. It’s unlikely that they’ll have a diagnosis by the time they leave, but they will continue their workup with PCP or pulmonology for definitive diagnosis and management. 

Decisional Capacity POD

DECISIONAL CAPACITY

Decisional capacity is the ability of a patient to make medical decisions on their own behalf. Any physician can determine if a patient has or lacks capacity, not just psychiatrists. We as emergency physicians must be extremely comfortable with assessing decisional capacity, whether it’s for a disposition (e.g. patient wants to go home), for a procedure (e.g. patient doesn't want a lumbar puncture), or for any other medical decision.

There are 4 components of decisional capacity

1. What do I have? - understanding of current condition

2. What are my options? - understanding of possible choices

3. What will I do? - ability to communicate a choice

4. Why? - ability to reason appropriately and understand likely consequences of decisions

Common Scenarios:

Elderly/possibly demented people that want to go home despite a possible dangerous condition

• They’ve already communicated a choice

• You need to figure out if they understand their condition, their available choices (maybe home with PMD fu, vs CDU, vs admit), and if they can reason (why do you want to go home? What are the risks and benefits of going home? What are the risks and benefits of admission?)

• Reach out to family or a healthcare proxy to A.) help determine if the patient is acting at baseline and if their decision is consistent with their core values, and B.) make a decision for them if they lack capacity (responsibility of next of kin or healthcare proxy)

Drunk or otherwise intoxicated people that want to go home despite indication for workup of a possible dangerous disease process

• Most of the time they don’t have capacity; their ability to reason is often significantly impaired

Psychiatric patients

• While technically within our purview to assess capacity in all patients, you should err on the side of consulting psychiatry for these patients; they are the experts in differentiating eccentric behavior from an exacerbation of psychiatric illness that truly impairs judgement

Pro tips

• The decision should ideally be consistent over time! If you ask multiple times and their answer keeps changing, they are not communicating a clear choice

• Involve the family and/or PMD whenever possible with these decisions

• If it’s extremely difficult, you feel like you’re not getting anywhere, or you’re out of time, call psych for help

• Try to let go of any biases toward this patient that may have accrued during their stay (it doesn’t matter that they’ve been a pain in the neck during their ED stay, you should not lower your threshold for saying they have capacity so you can get them out of the ED)

• Always drop a note; it should address the four elements of decisional capacity

Example Capacity Note

pt wants to be discharged and has capacity to make this decision:

pt understands that she has pneumonia (#1)

understands options including hospital admission, CDU, and home with PMD fu (#2)

pt chooses home with PMD (#3) fu and reasons that she prefers to be at home at her age because it’s more comfortable even if it comes with a higher mortality risk given her condition (#4)

she has expressed this choice multiple times during her ED stay, has an active DNR/DNI order, and her family/PMD supports her decision (consistency during ED stay, consistent with core values, family and PMD on board)