Nephrotic & Nephritic Syndromes
This nephrotic syndrome is the most common cause in children and classically shows effacement of podocyte foot processes on electron microscopy with NO immune deposits on immunofluorescence.
What is minimal change disease?
This is the most common type of kidney stone overall, accounting for roughly 80% of cases.
What is a calcium stone (calcium oxalate)?
This type of renal tubular acidosis is caused by a defect in proximal tubule bicarbonate reabsorption and is associated with hypokalemia.
What is type 2 (proximal) RTA?
This small-vessel vasculitis, formerly known as Wegener granulomatosis, classically involves the nasopharynx, lungs, and kidneys.
What is granulomatosis with polyangiitis (GPA)?
This electrolyte disturbance is both a classic sign of digoxin toxicity AND, paradoxically, a marker of poor prognosis in digoxin use.
What is hyperkalemia?
This autoantibody target — a transmembrane receptor found on glomerular podocytes — is associated with primary membranous nephropathy.
What is the phospholipase A2 receptor (PLA2R)?
This classic symptom pattern occurs only once a stone obstructs the ureter or ureteropelvic/ureterovesical junction.
What is "loin to groin" pain?
This syndrome, caused by generalized proximal tubule dysfunction, is associated with type 2 RTA and carries an increased risk of hypophosphatemic rickets.
What is Fanconi syndrome?
This immune complex, deposited following an upper respiratory tract infection, causes the vasculitis formerly known as Henoch-Schönlein purpura.
What is IgA (IgA vasculitis)?
This visual disturbance — blurry yellow vision — is a hallmark finding of digoxin toxicity.
What is xanthopsia?
This glomerulopathy shows no immune complex deposits on immunofluorescence (may show nonspecific IgM/C3/C1) and ultimately progresses to chronic kidney disease, unlike its "minimal change" cousin.
What is focal segmental glomerulosclerosis (FSGS)?
This inflammatory bowel condition predisposes to calcium oxalate stones because fat malabsorption causes calcium to bind fats instead of oxalate, allowing free oxalate absorption.
What is Crohn disease?
This class of drugs, along with aminoglycosides and lead exposure, can cause proximal (type 2) RTA by directly inhibiting bicarbonate reabsorption.
What are carbonic anhydrase inhibitors?
This term describes a glomerular disorder affecting greater than 50% of glomeruli.
What is "diffuse"?
These antiarrhythmic drugs — including verapamil, amiodarone, and quinidine — decrease renal clearance of digoxin, raising the risk of toxicity when co-administered.
What are verapamil, amiodarone, and quinidine (or propafenone)?
In SLE patients, this is the most common TYPE of nephrotic syndrome, distinct from diffuse proliferative glomerulonephritis, which is the most common nephritic presentation in the same disease.
What is membranous nephropathy?
This is the urine crystal shape characteristic of calcium oxalate stones.
What is an envelope (or dumbbell) shape?
In this type of RTA, hypoaldosteronism or aldosterone resistance leads to hyperkalemia, which in turn decreases NH3 synthesis in the proximal tubule and reduces NH4+ excretion, causing metabolic acidosis.
What is type 4 (hyperkalemic) RTA?
This structural disruption underlies nephritic syndrome, in contrast to the podocyte disruption that characterizes nephrotic syndrome.
What is glomerular basement membrane (GBM) disruption?
This treatment for severe digoxin toxicity directly binds to and neutralizes the drug.
What is anti-digoxin Fab fragments?
This autoantibody targets the alpha-3 chain of type IV collagen, producing a syndrome with both pulmonary hemorrhage and rapidly progressive glomerulonephritis — distinguished from a similarly-named inherited collagen defect by its autoimmune (rather than genetic) etiology.
What is Goodpasture syndrome (anti-GBM antibody)?
This is the underlying urinary abnormality most commonly responsible for calcium oxalate stone precipitation, occurring even when serum calcium and urine calcium are otherwise normal.
What is hypocitraturia?
This class of medications — including ACE inhibitors, ARBs, NSAIDs, heparin, and cyclosporine — can precipitate type 4 RTA through impaired production or action of this hormone.
What are drugs causing hypoaldosteronism/aldosterone resistance (e.g., ACE inhibitors/ARBs/NSAIDs/heparin/cyclosporine)?
This urinary finding localizes hematuria to a glomerular or renal tubular origin, distinguishing it from non-glomerular bleeding sources like bladder cancer or kidney stones.
What are RBC casts (or dysmorphic RBCs)?
This dihydropyridine calcium channel blocker is contraindicated in unstable angina or MI because its potent vasodilation triggers reflex tachycardia that can worsen myocardial ischemia.
What is nifedipine?