By Gary M. White, MD

Gram-negative folliculitis about the mouth

Gram-negative folliculitis is a term used to describe an uncommon bacterial infection of the follicles about the mouth.


Gram-negative folliculitis may present as an outbreak of centrofacial papules and pustules in a male patient with oily skin. Involvement of the infranasal area, and an excessively oily face have been suggested as helpful diagnostic signs. The condition is often misdiagnosed as acne and in fact, this infection may occur as a consequence of oral antibiotic treatment for acne.


Cultures should be taken of a pustule. Some patients have also had colonization of the urogenital tract and thus swabs of the rectum, vagina, and even ejaculate may be indicated in refractory cases. Organisms include E. Coli, Klebsiella, Pseudomonas, Citrobacter koseri [Infection. 2015 Jan 29] and Enterobacter. Nodulocystic lesions may contain Proteus. Staphylococcus aureus may be found.


The current antibiotic that the patient is taking (if there is one) should be stopped as it may be reducing the normal flora and contributing to the infection. Appropriate oral antibiotic treatment as directed by sensitivities should be given. Occasionally, isotretinoin is needed, especially in cases of both acne and recurrent gram-negative folliculitis.

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Gram-negative folliculitis about the mouth


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