Staphylococcus-associated glomerulonephritis
Staphylococcus-associated glomerulonephritis is an immune-complex-mediated nephritic syndrome that develops during or shortly after an active Staphylococcus aureus infection, most often in older adults with diabetes, an indwelling device, or endocarditis, distinguished from poststreptococcal glomerulonephritis by its adult predominance, concurrent rather than delayed infection, and frequent need for renal biopsy; management centers on eradicating the staphylococcal focus alongside supportive nephritic care.
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What this article covers
- Overview
An immune-complex-mediated glomerulonephritis triggered by an active or recent Staphylococcus aureus infection, rather than the pharyngeal or skin group A streptococcal infection that causes classic…
- Epidemiology
Affects adults far more often than children, in contrast to PSGN, which predominates in school-age children.
- Risk factors
Active or recent Staphylococcus aureus bacteremia, endocarditis, osteomyelitis, or catheter-related bloodstream infection, the direct antecedent providing the ongoing antigenic stimulus for immune complex formation.
- Pathophysiology
A type III hypersensitivity reaction drives glomerular injury: circulating or in situ immune complexes containing staphylococcal antigen and host antibody activate complement, producing consumptive…
- Clinical features
Nephritic syndrome developing during or shortly after a documented or clinically evident staphylococcal infection is the defining presentation: hematuria (often gross, tea- or cola-colored), variable…
- Differential diagnosis
Poststreptococcal glomerulonephritis: the same immune-complex mechanism, but predominantly in children 1 to 3 weeks after a resolved group A streptococcal pharyngitis or skin infection, with elevated…
- Diagnosis
Staphylococcus-associated glomerulonephritis is confirmed by renal biopsy showing a diffuse proliferative glomerulonephritis with granular ("lumpy-bumpy") glomerular deposits of immunoglobulin and C3…
- Management
First, aggressively identify and eradicate the staphylococcal source, since ongoing antigen exposure from an unaddressed focus perpetuates glomerular injury.
- Complications
Progressive or rapidly progressive glomerulonephritis, with crescent formation and a faster decline in renal function than the typical self-limited course.
- Prognosis
Renal outcome is closely tied to eradication of the staphylococcal source: renal function and complement typically improve as the infection clears with source control and a complete antibiotic course.
- Prevention
Promptly remove or exchange infected central venous catheters, dialysis access, or other prosthetic material colonized with Staphylococcus aureus, a recognized driver of this glomerulonephritis.
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Related articles
- Bacteremia
Bacteremia is the presence of viable bacteria in the blood, confirmed by positive blood cultures, that ranges from transient and clinically silent to the trigger for sepsis and septic shock requiring urgent source identification and antimicrobial therapy.
- Bacterial infective endocarditis
Bacterial infection of the endocardial surface, usually a heart valve, producing vegetations that destroy the valve and embolize; diagnosis rests on the modified Duke criteria (blood cultures plus echocardiography) and treatment is a prolonged organism-directed intravenous antibiotic course, with valve surgery for heart failure, uncontrolled infection, or embolic recurrence.
- Osteomyelitis
Osteomyelitis is bone infection from hematogenous seeding or contiguous spread, most often from Staphylococcus aureus, presenting as subacute pain with or without a draining sinus tract and confirmed by bone biopsy culture. Empiric antibiotics are withheld until biopsy in a stable patient, and treatment combines source control with 4 to 6 weeks of culture-directed antibiotics, extended to 6 weeks or indefinite suppression for hardware-associated or chronic disease.
- Streptococcal pharyngitis
Streptococcal pharyngitis is an acute infection of the tonsils and pharynx caused by group A Streptococcus pyogenes, presenting with rapid-onset sore throat, fever, tonsillar exudates, and tender anterior cervical lymphadenopathy without cough; diagnosis relies on the Centor criteria to guide rapid antigen testing, and treatment with penicillin or amoxicillin prevents suppurative complications and acute rheumatic fever.
- Cellulitis
Cellulitis is a nonpurulent, spreading infection of the deep dermis and subcutaneous fat, usually caused by beta-hemolytic streptococci, diagnosed clinically and treated with antibiotics alone since there is no collection to drain.