Why this matters
Treating a MRSA abscess as a spider bite delays appropriate antibiotic therapy and incision-and-drainage, allowing the infection to progress. Multiple studies show >80% of presumed 'spider bites' in emergency departments are actually MRSA.
Distinguishing features
MRSA: warm, fluctuant, often multiple lesions or recurrent; purulent drainage; rapid expansion; often history of recent close contact or gym/locker-room exposure.
Spider bite: usually single lesion with two close puncture marks; rarely purulent unless secondarily infected; the patient may or may not recall a bite event.
References
- [1]Methicillin-Resistant S. aureus Infection Misidentified as Spider Bites - CDC MMWR. Accessed June 2026.
Related in Bites and medical
- How to identify a spider biteMost lesions blamed on spiders are not spider bites.
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- Are spider bites dangerous?For the average person in North America, spider bites are very rarely dangerous.
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