Glomerular Disease
While on your nephrology rotation, you may be consulted to diagnose or manage a glomerular disease. There are many new and emerging therapies for these diseases which will hopefully improve outcomes for many patients. While glomerular disease is often a scary topic for many learners, these reference materials will help overcome some of that fear to help embrace one of the most interesting areas of nephrology.
Glomerular disease refers to disorders that affect the kidney’s filtering units (glomeruli) and is broadly categorized into nephritic and nephrotic processes. Nephritic syndrome reflects inflammation within the glomerulus, leading to disruption of the capillary walls. This classically presents with hematuria (often with dysmorphic red blood cells (RBCs)s or RBC casts), subnephrotic proteinuria, hypertension, and decreased kidney function due to reduced filtration. Common causes include post-infectious glomerulonephritis, IgA nephropathy, and lupus nephritis. In contrast, nephrotic syndrome is primarily due to injury to the podocytes (filtration barrier cells), resulting in heavy proteinuria (>3.5 g/day), hypoalbuminemia, edema, and hyperlipidemia, with relatively less inflammation. Classic causes include minimal change disease, focal segmental glomerulosclerosis (FSGS), and membranous nephropathy. Understanding whether a glomerular disease is nephritic or nephrotic helps guide diagnostic evaluation, management, and prognosis.
Remember, this is a great opportunity to look at urine microscopy for dysmorphic red blood cells (acanthocytes) or red blood cell casts!
1.) Dirty Medicine YouTube: “Nephrotic vs. Nephritic Syndromes:
To start, the following YouTube video from Dirty Medicine provides a clear overview of the key differences between nephritic and nephrotic syndromes.
2.) Curbsiders Podcast: #250 Nephrotic vs. Glomerulonephritis
This Curbsiders Internal Medicine podcast provides an additional overview of the key differences between nephrotic and nephritic syndromes, including their clinical features, diagnostic evaluation, management, and prognosis.
3.) Nephritic vs. Nephrotic Syndrome
These slides provide a nice quick reference for comparing Nephrotic vs. Nephritic syndromes.
4.) A beginner’s guide to the clinical approach and concepts of glomerular disease: a mini review.
This “beginner’s guide” provides a nice overview of how to approach and manage glomerular disease.
5.) Takeaways for Clinicians from the KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases.
These are the key takeaways on managing glomerular disease from the KDIGO 2021 guidelines. This goes well beyond what you would be expected to remember, but it is a helpful and quick reference for treatment of some of the most common glomerular diseases.
Now that you’ve read through some background information, try working through these cases that demonstrate some possible presentations of glomerular disease.
Cases:
NephSim Case 1 – Post-infectious GN
A 58 year old woman with chronic kidney disease stage III, diabetes mellitus, and hypertension who had a recent admission for lower extremity cellulitis and is now presenting with swelling in her legs and exertional dyspnea.
NephSim Case 7 – Lupus Nephritis
A 32 year old women who no known past medical history presents with two weeks of intermittent fevers, fatigue, peripheral edema, and joint pain/swelling of the wrists and ankles.