Diagnosis

Doctors usually diagnose impetigo by looking at the distinctive sores. Lab tests generally aren't necessary.

If the sores don't clear, even with antibiotic treatment, your doctor may take a sample of the liquid produced by a sore and test it to see what types of antibiotics might work best on it. Some types of the bacteria that cause impetigo have become resistant to certain antibiotic drugs.

May 10, 2016
References
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  2. Baddour LM. Impetigo. http://www.uptodate.com/home. Accessed Feb. 11, 2016.
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  4. Ferri FF. Impetigo. In: Ferri's Clinical Advisor 2016. Philadelphia, Pa.: Mosby Elsevier; 2016. http://www.clinicalkey.com. Accessed Feb. 11, 2016.
  5. Habif TP. Bacterial infections. In: Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. Philadelphia, Pa.: Saunders Elsevier; 2016. http://www.clinicalkey.com. Accessed Feb. 11, 2016.
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