A 2 year old, previously healthy female presents to the ED with diffuse lower extremity swelling and abdominal distention. According to her mother, patient had been sick with strep throat 10 days prior and was treated with a course of amoxicillin. The patient had been compliant with the medication, which was scheduled to end that evening. The previous evening, her mother had initially noted facial swelling, and given the patient Benadryl with some improvement. On the day of the ED visit, the mother had noticed the patient developed swelling in both of her lower extremities and had a distended appearance of her abdomen without any signs of pain. The patient did not have any rashes or hives. She had been having improved oral intake following her strep infection. She had no appreciable changes in her urinary or bowel habits.
On examination, the patient is afebrile, and vital signs are within normal limits. She has a distended appearance to her abdomen with normal bowel sounds, no tenderness. She exhibits symmetric bilateral lower extremity edema that extends from feet to knees. There is no erythema or rash noted. HEENT examination is unremarkable.
What is the most likely cause of her symptoms?
A. Congestive heart disease
B. Nephrotic syndrome
C. Thyroid disease
D. Liver failure
E. Post strep glomerulonephritis
Labs are significant for an elevated total protein (4.7), low albumin (1.9). No leukocytosis. Normal BUN/Cr, AST, ALT, ALP. Urinalysis is significant for protein of 500 and no blood.
With that information, what is the most likely cause of her symptoms?
Remind me, what is nephrotic syndrome again?
- Characteristics includes persistent heavy proteinuria, hypoproteinemia, hypercholesterolemia, and edema
- There is increased glomerular permeability due to alterations to normal glomerular cellular and basement membrane barrier
- These alterations cause loss of ability to restrict urinary loss of protein.
- Albumin is the protein most affected
- Edema is secondary to fluid shifts (low plasma oncotic pressure so fluid shifts from vascular to interstitial compartments) and due to increased activation of RAAS
- Elevated serum lipids and protein occur because of liver compensation for loss of proteins
- Eventually liver synthesis of albumin cannot keep up with urinary loss of proteins
- Underlying cause can be renal or due to a systemic disease
Are there different types?
- Minimal change disease
o Minimal change disease is the most common cause in children
oMore than 80% of children who are less than 7 years old with have Nephrotic syndrome due to minimal change disease.
oChildren ages 7- 16, 50% will have nephrotic syndrome due to minimal change disease
Males are affected 2:1 compared to females (in children, not adults)
- Primary Focal Segmental Glomerulosclerosis
o Focal segmental glomerulosclerosis (FSGS) is second most common
- Membranoproliferative glomerulonephritis
- diopathic membranous nephropathy (congenital)
- Lupus glomerulonephritis
- Henoch-Schonlein purpura
- Chronic infections (Hep C, HIV)
- Acute infections (viral, bacterial, or parasitic)
- Allergic reactions
- Diabetes Mellitus
- Congestive heart failure
- Renal vein thrombosis
How do these patient present?
- Patients can present with;
o Nonspecific symptoms such as fever, malaise
o Non urinary symptoms such as arthritis, rash
o Urinary symptoms such as edema, hypertension
- In the first few years of life, often present with periorbital swelling with or without generalized edema
- Edema ranges from mild periorbital swelling to severe anasarca
- Absence of hematuria, renal insufficiency
- Typically after infection or other stress. Ex. Viral illness, insect bite
What labs are important?
- Urine protein creatinine measuring with a ratio >2.0 is in the nephrotic range
o Adults, children > 2yrs – Urine P:Cr 0.2 is considered normal
o Children 6 mo – 2 yrs – Urine P:Cr 0.5 is considered normal
- Tests to order include
o UA for protein
o Serum creatinine, BUN
o Serum albumin, total protein
o Serum cholesterol, triglycerides
o Renal Ultrasound
o Serum CBC, BMP
- Expectations on aforementioned labs
o Serum albumin is decreased (albumin <3.0)
o Cholesterol levels are increased
o UA shows proteinuria with >2 g/ m2/24 hours
o Normal complement levels (in minimal change disease)
- For asymptomatic proteinuria, need to establish persistence, options include;
o AM/PM urine dipsticks
o Spot AM urine protein/creatinine ratio
- Biopsy is only performed when cause suspected to be something other than MCD
What do I do once I’ve figured out its nephrotic syndrome?
- Consult a pediatric nephrologist
- Patients will typically be started on steroids (without renal biopsy if MCD is most likely)
o Prednisone 2 mg/kg/day (max 60 mg)
o Response is typically seen within 4 weeks but treatment continues for 12 weeks
o Renal biopsy if no response to steroids
- Restricted salt intake
- Loop diuretics may be indicated for severe edema
- Beta blockers or calcium channel blockers for severe HTN (persistent HTN treat with ACEIs)
- Complications include;
o Hypercoagulable state à increased risk of thromboembolism
o Atherosclerotic heart disease
Other useful information:
- There are benign cause of proteinuria including isolated proteinuria (no other renal symptoms), transient proteinuria (can be caused by fevers or exercise), orthostatic proteinuria (protein excretion only in upright position)
- Most children go into remissions, however, nearly 80% will have relapse of minimal change disease
- Many children with FSGS will go into end stage renal failure
How’d our patient do?
Great! She was admitted overnight primarily for initial management and family teaching. She was started on course of Prednisone for presumed minimal change disease. She has had outpatient follow up with pediatric nephrology and continued her steroid course with slow improvement in her proteinuria.
Faculty Reviewer: Dr. Chris Merritt
1. O’Connel, Theodore X. Instant Work-ups: A clinical guide to pediatrics. Proteinuria. Chap 36. 245-250
2. Marcdante, Karen. Nelson’s Essentials of Pediatrics. Nephrotic syndrome and proteinuria. 7th edition. 2015. Chapter 162. Pgs 556- 558
3. Madaio, Michael. The Diagnosis of Glomerular Disease; Acute Glomerulonephritis and the Nephrotic Syndrome. Arch Internal Med. 2001; 161: 25-34
4. Pal, Abhijeet. History of Nephrotic Syndrome and Evolution of its Treatment. Frontiers in Pediatrics. May 30th 2016; 4: 56.
5. El Bakkali, Loubna. Nephrotic Syndrome in The Netherlands: a population-based cohort study and review of the literature. Pediatric Nephrology. 2011; 26: 1241-1246