Journal of Family and Community Medicine

: 2017  |  Volume : 24  |  Issue : 3  |  Page : 203-

A bump in the groin: Cutaneous actinomycosis

Susan A Piggott, Morteza Khodaee 
 Department of Family Medicine, School of Medicine, University of Colorado, Denver, CO 80238, USA

Correspondence Address:
Morteza Khodaee
Department of Family Medicine, School of Medicine, University of Colorado, AFW Clinic, 3055 Roslyn Street, Denver, CO 80238

How to cite this article:
Piggott SA, Khodaee M. A bump in the groin: Cutaneous actinomycosis.J Fam Community Med 2017;24:203-203

How to cite this URL:
Piggott SA, Khodaee M. A bump in the groin: Cutaneous actinomycosis. J Fam Community Med [serial online] 2017 [cited 2021 May 12 ];24:203-203
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A 27-year-old healthy female presented with a painful right groin mass 1 week after removing an “ingrown hair” at the site. At presentation, no fluid had drained spontaneously from the mass and the patient was otherwise well. Physical examination revealed normal vital signs and a 2 cm × 1 cm tender, fluctuant mass in the right groin with surrounding erythema and warmth. Incision and drainage produced 2 mL of purulent bloody fluid. The patient was prescribed cephalexin. Gram stain showed no organisms, heavy red blood cells, and few white blood cells. Anaerobic culture grew few Gram-positive cocci and Actinomyces species. After discussing with infectious disease and because of the patient's young age and good health with no systemic signs or symptoms, a 10-day course of oral ampicillin was advised. Her symptoms resolved after this antibiotic treatment.

Actinomyces is a rare cause of invasive bacterial disease.[1] The species are naturally found in the human oropharyngeal, gastrointestinal, and genitourinary tracts.[1] Diagnosis is often difficult as Actinomyces can mimic conditions such as tuberculosis or a malignancy.[2] Up to 60% of reported cases are oral-cervicofacial and are associated with odontogenic infection.[1] Most cases occur in male patients aged 20–60 years old.[3] Risk factors include poor dental hygiene or dental procedures, intrauterine device use, immunosuppression, appendicitis, and diverticulitis.[2],[3] Cutaneous actinomycosis is a rarer form of disease which usually occurs through hematogenous spread, direct inoculation through trauma, or direct extension.[4] Localized infection can form an abscess or fistualize and exude characteristic yellow sulfur granules.[1],[5] Due to the rarity of cutaneous disease, no evidence-based guidelines are available and most data are from case reports.[1],[4] The best chance of identification is through Gram stain and culture with prolonged anaerobic incubation.[1] Accurate identification is often missed owing to inhibition of growth by other organisms, inadequate culture environment or length, and previous antibiotic use.[1] First-line therapy for actinomycosis is a beta-lactam antibiotic.[1],[3] High doses of prolonged therapy (2–12 months) based on location and complexity are standard.[3] However, more individualized regimens based on severity, location, and treatment response are acceptable with close monitoring.[2]

Every cutaneous abscess should undergo incision and drainage and a sample sent for culture. Suspected cases of actinomycosis should be cultured with prolonged incubation of at least 10 days in aerobic and anaerobic conditions with Gram stain.[1] Due to the lack of clinical guidelines, a consultation with infectious disease for the choice of antibiotic and treatment length is recommended.

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3Anderson K, Scherger JM, Opal SM, Mylonakis T. Actinomycosis. Philadelphia, PA: Elsevier:First Consult, Clinical Key; 2012.
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