Can Bursitis Occur with Gout in the Knee?
Yes, bursitis can absolutely occur in conjunction with gout in the knee, as monosodium urate crystals can deposit directly in bursae around the knee joint, triggering acute bursal inflammation. 1
Mechanism of Gout-Related Bursitis
Gout causes bursitis through the same pathophysiologic mechanism as gouty arthritis—monosodium urate crystals accumulate in bursae and other tissues, creating inflammatory responses wherever they deposit. 2 The knee has multiple bursae that can be affected:
- Prepatellar bursa (superficial, anterior to the patella) 3
- Deep infrapatellar bursa (posterior to the patellar tendon, anterior to the tibial tuberosity) 4, 5
- Superficial infrapatellar bursa 3
- Bursae in the popliteal region (gastrocnemius and semimembranosus) 6
Clinical Recognition
When evaluating knee pain with suspected gout, look for these specific features that suggest bursal involvement:
- Rapid onset of severe pain reaching maximum intensity within 6-12 hours 2
- Overlying erythema combined with rapid-onset severe pain strongly suggests MSU crystal deposition 2
- Localized swelling over specific bursal locations rather than diffuse joint swelling 3
- Risk factors: male gender, cardiovascular comorbidities, and hyperuricemia support gout as the underlying cause 2
Critical Diagnostic Pitfall: Rule Out Infection
The most important clinical caveat is that gout and septic bursitis can coexist, and this must always be excluded. 2, 7 A case report documented simultaneous Staphylococcus aureus infection and uric acid crystals in the same bursa. 7
When to Aspirate
If infection is suspected, bursal aspiration must be performed with fluid examined using: 3
- Gram stain and culture (mandatory even if crystals are found) 2
- Crystal analysis under polarized microscopy for needle-shaped, negatively birefringent MSU crystals 2
- White blood cell count 3
- Glucose measurement 3
Aspiration is particularly critical in patients with increased infection risk: elderly patients, those with severe comorbidity, or immunodeficiency. 7
Diagnostic Imaging Approach
When aspiration is not feasible or to supplement clinical evaluation:
- Ultrasound should be the initial advanced imaging modality, detecting tophi with 65% sensitivity and 80% specificity as hyperechoic masses with a "wet clumps of sugar" appearance 2
- Ultrasound can distinguish bursitis from cellulitis and detect fluid accumulation 1
- Dual-energy CT has 85-100% sensitivity and 83-92% specificity for detecting MSU crystal deposits, providing color-coded images that distinguish crystals from other pathology 2
For deep infrapatellar bursitis specifically, ultrasound shows an anechoic fluid-filled structure immediately posterior to the distal patellar tendon and anterior to the tibial tuberosity. 4
Treatment Algorithm
For Confirmed Gouty Bursitis (Infection Ruled Out):
Treat by addressing the underlying gout, with intrabursal corticosteroid injections often used for inflammatory bursitis. 3 Treatment options include:
- Colchicine, NSAIDs, or corticosteroids as first-line acute anti-inflammatory therapy 6
- Consider urate-lowering therapy for recurrent episodes 8
For Chronic Microtraumatic Bursitis:
Bursal aspiration is generally NOT recommended because of the risk of iatrogenic septic bursitis. 3 Treat conservatively and address the underlying cause. 3
For Septic Bursitis:
Antibiotics effective against Staphylococcus aureus are the initial treatment, with surgery reserved for cases not responsive to antibiotics or recurrent cases. 3 Hospitalize acutely ill patients for intravenous antibiotics; outpatient oral antibiotics may be considered for those not acutely ill. 3
Documentation of Gout in Knee Bursae
Gout has been specifically documented in the deep infrapatellar bursa of the knee in published case reports, representing rare but established presentations. 5 Gout is recognized as a cause of inflammation in various knee bursae alongside infection, juvenile idiopathic arthritis, and trauma. 4