Actinomyces is a gram-positive facultative anaerobe common in the gastrointestinal microbiota. Because of the close proximity of the vagina and anus, it can colonize the genital tract in women. Actinomyces may ascend into the upper genital tract and cause severe pelvic inflammatory disease, particularly in the setting of long-term intrauterine device (IUD) use.
However, because Actinomyces can be part of the normal vaginal flora, its presence does not necessarily indicate active pelvic infection. In addition, Pap testing has poor specificity for Actinomyces, with a high false-positive rate (eg, 50%), even in patients with an IUD.
Therefore, patients with Actinomyces or Actinomyces-like organisms found incidentally on Pap testing require additional evaluation for symptoms (eg, pelvic pain, abnormal vaginal discharge). Asymptomatic patients, such as this one, have minimal risk of infection. Therefore, they can maintain their IUD and require no further management.
In contrast to this patient, those with Actinomyces on Pap testing who are symptomatic (eg, abnormal vaginal discharge, pelvic pain) require IUD removal and empiric broad-spectrum antibiotics for pelvic inflammatory disease. The IUD is sent for culture; those with positive Actinomyces cultures require additional targeted treatment with penicillin.
Patients with severe pelvic actinomycosis may have systemic symptoms (eg, fever, weight loss) and a pelvic mass (ie, abscess). These patients require IUD removal and culture, pelvic ultrasound, and prolonged penicillin therapy (eg, 6-12 months).
<aside> 💡 Cervical culture is typically not performed because a positive culture for Actinomyces may be due to asymptomatic colonization. Even in symptomatic patients, a culture from the IUD is preferred over a cervical culture.
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