These two groups of disorders damage the kidney in different ways. Glomerulonephritis (GN) is immune-mediated inflammation of the glomeruli (the filtering units). Pyelonephritis is bacterial infection of the renal pelvis and kidney tissue, usually ascending from the bladder.

Glomerular disorders

• Acute post-streptococcal glomerulonephritis (PSGN) — follows infection with group A beta-hemolytic streptococcus: about 1–2 weeks after pharyngitis or 3–6 weeks after skin infection (impetigo). Immune complexes deposit in glomeruli → reduced filtration → sodium and water retention → edema and hypertension. Most common in children aged 5–12; usually resolves, prognosis is worse in adults.
• IgA nephropathy — the most common primary GN worldwide. IgA deposits in the glomeruli; classic sign is gross hematuria within 1–3 days of an upper respiratory infection (at the same time as the infection, unlike the delay in PSGN). May progress slowly to CKD; can recur after transplant.
• Rapidly progressive GN — loss of kidney function over days to weeks (e.g., anti-GBM disease, ANCA vasculitis); an emergency.
• Chronic GN — progressive scarring leading to CKD and kidney failure.

Nephrotic syndrome (a pattern of glomerular injury) — increased glomerular permeability to protein:

• Heavy proteinuria > 3.5 g/day (adults)
• Hypoalbuminemia (serum albumin < 3.0 g/dL (30 g/L))
• Generalized edema (low oncotic pressure) and hyperlipidemia
• Also hypercoagulability (loss of anticoagulant proteins — renal vein thrombosis, DVT, PE) and infection risk (loss of immunoglobulins)

Pyelonephritis

• Acute: ascending infection; risk factors are urinary obstruction or stasis (stones, enlarged prostate, strictures), vesicoureteral reflux, pregnancy, catheters, diabetes, and instrumentation
• Chronic: repeated infections with scarring, often with reflux or obstruction → progressive CKD and hypertension

Acute glomerulonephritis

• Recent sore throat or skin infection — ask first
• Periorbital and facial edema, worse in the morning; weight gain
• Dark, cola- or tea-colored urine; decreased urine output
• Hypertension, headache (risk of hypertensive encephalopathy), signs of fluid overload (crackles, dyspnea)
• Fatigue, anorexia, flank or back discomfort

Nephrotic syndrome

• Marked generalized edema (anasarca), ascites, frothy urine, weight gain, fatigue

Acute pyelonephritis

• High fever, shaking chills, flank pain, CVA tenderness
• Nausea, vomiting, malaise; may have dysuria and frequency
• Signs of sepsis: hypotension, tachycardia, altered mental status, low urine output

• Urine protein: 24-hour urine protein or urine protein-to-creatinine ratio (nephrotic range > 3.5 g/day)
• Serum albumin, lipids in nephrotic syndrome
• Urine culture: clean-catch midstream specimen collected before the first antibiotic dose

Glomerulonephritis

• Sodium and fluid restriction based on edema, blood pressure, and urine output
• Loop diuretics (furosemide) for edema and fluid overload — monitor potassium (hypokalemia), BP, ototoxicity with rapid IV doses
• Antihypertensives; in chronic proteinuric disease, ACE inhibitors or ARBs reduce proteinuria and slow progression — watch for hyperkalemia, a rise in creatinine, angioedema (ACE inhibitors), and cough; contraindicated in pregnancy
• Antibiotics (penicillin) only if streptococcal infection is still present; antibiotics do not reverse PSGN
• Protein intake is not increased; it is usually normal (about 0.8 g/kg/day), with restriction only when azotemia is significant
• Immune types (IgA, lupus, vasculitis, nephrotic): corticosteroids and other immunosuppressants per specialist — monitor glucose, BP, infection, mood, bone health
• IgA nephropathy: RAS blockade, and newer agents (e.g., SGLT2 inhibitors, targeted therapies) per nephrology (see Topic 53 for SGLT2 inhibitor safety)
• Nephrotic syndrome: diuretics, ACE inhibitor/ARB, statin, and anticoagulation for thrombosis when indicated
• Dialysis for severe fluid overload, hyperkalemia, or uremia

Pyelonephritis

• Antibiotics based on culture and local resistance: oral fluoroquinolone or TMP-SMX when susceptible for mild illness; IV ceftriaxone or broader agents for severe illness
• Pregnancy: usually admitted for an IV beta-lactam (e.g., ceftriaxone); avoid fluoroquinolones, and avoid TMP-SMX in the first trimester and near term
• TMP-SMX: hyperkalemia (especially with ACE inhibitors/ARBs), sulfa allergy (see Topic 51)
• Duration for improving clients: 5–7 days of a fluoroquinolone or 7 days of another effective agent (IDSA 2025); switch IV to oral when stable
• Fluoroquinolone safety: tendon rupture, neuropathy, QT prolongation, dysglycemia, photosensitivity; separate from calcium and antacids
• Relieve obstruction (ureteral stent or nephrostomy) if present
• Sepsis bundle when septic: fluids, cultures, early antibiotics

Listed in priority order.

1. Watch for sepsis (pyelonephritis) — hypotension and tachycardia are the key warning signs of progression to septic shock; also confusion and oliguria. Report immediately, start IV access and fluids as prescribed, obtain cultures, and give antibiotics promptly
2. Monitor fluid status and blood pressure (GN)
   • Daily weight (same time, scale, clothing) — the best indicator of fluid retention
   • Strict intake and output; edema; lung sounds for crackles
   • BP frequently; report severe hypertension, headache, visual change, or seizures (hypertensive encephalopathy)
3. Fluid balance
   • GN: restrict sodium and fluid as prescribed (fluid allowance often based on the previous day's output plus insensible loss)
   • Pyelonephritis: encourage fluids (unless contraindicated) to flush bacteria and dilute urine
4. Monitor labs: BUN, creatinine, potassium, albumin, urine protein
5. Comfort
   • Pyelonephritis: warm compress to the flank, analgesics and antipyretics as prescribed
   • Rest during the acute phase; resume activity gradually as edema, hematuria, and BP improve (strict bed rest is not required)
6. Skin care for edema — reposition, protect fragile skin, elevate edematous limbs
7. Infection prevention in nephrotic syndrome and in clients on immunosuppressants; watch for thrombosis (leg swelling, chest pain, flank pain with hematuria)

Glomerulonephritis

• Low-sodium diet; follow the fluid allowance; weigh daily and report a gain of more than about 1 kg (2.2 lb) in a day or 2 kg (4.4 lb) in a week, or as the provider specifies
• Report decreased urine output, new swelling, headache, or dark urine
• Prompt evaluation and full treatment of strep throat and skin infections
• Hematuria and proteinuria can persist for months after PSGN — keep follow-up visits
• Avoid NSAIDs and other nephrotoxins unless approved

Pyelonephritis

• Complete the entire antibiotic course, even when feeling better
• Drink adequate fluids during treatment and after
• Repeat culture if symptoms persist or recur; report fever, flank pain, or vomiting (may need IV therapy)
• Prevention measures from Topic 51: void regularly and after intercourse, front-to-back wiping, avoid douches

Chronic kidney involvement (chronic GN or chronic pyelonephritis)

• Blood pressure control is the most important way to slow progression
• Avoid NSAIDs; treat UTIs promptly; do not wait for symptoms to settle alone
• Avoid extreme fluid restriction unless prescribed; protein intake per kidney team (not high-protein)

• Septic shock from pyelonephritis — hypotension, tachycardia, altered mental status
• Renal or perinephric abscess; emphysematous pyelonephritis (diabetes)
• Hypertensive encephalopathy — severe headache, confusion, seizures
• Pulmonary edema / heart failure from fluid overload
• Acute kidney injury — oliguria, rising creatinine, hyperkalemia
• Rapidly progressive GN — rapidly rising creatinine; urgent nephrology referral
• Nephrotic syndrome: thromboembolism, infection (peritonitis), hyperlipidemia
• Progression to CKD and kidney failure — anemia (low erythropoietin), cardiovascular disease, mineral-bone disorder

• PSGN follows group A strep: about 1–2 weeks after sore throat, 3–6 weeks after impetigo — ask about recent sore throat or skin infection
• GN triad: hematuria (cola-colored urine), edema (periorbital), hypertension; ↑ ASO, ↓ C3
• GN care: restrict sodium and fluid, daily weight, BP control; not high-protein
• IgA nephropathy: gross hematuria at the same time as (1–3 days after) a respiratory infection
• Nephrotic syndrome: proteinuria > 3.5 g/day, albumin < 3.0 g/dL, edema, hyperlipidemia, plus clot and infection risk
• Pyelonephritis: fever, chills, flank pain, CVA tenderness, WBC casts
• Biggest risk factor for ascending infection: obstruction / urinary stasis (stones, enlarged prostate), reflux, catheters
• Hypotension and tachycardia signal progression toward septic shock
• Culture midstream, before antibiotics; complete the antibiotic course; fluids and warm flank compress for comfort
• Chronic disease: BP control slows progression; avoid NSAIDs; end-stage complications include anemia and cardiovascular disease