Recurrent Breast Abscess Caused by Gordonia bronchialis in an Immunocompetent Patient

Abstract

We present the first reported case of a recurrent breast infection caused by Gordonia bronchialis. The infection occurred in a 43-year-old immunocompetent female, and species level identification was obtained with 16S rRNA sequencing. CASE REPORTA 43-year-old female presented to hospital with a 4-day history of a tender mass in her left breast. On examination, there was marked fullness with erythema on the lateral aspect of the left breast extending to the areola and a palpable mass measuring 4 to 5 cm in diameter. Ultrasonic examination showed an extensive area of inflammatory changes but no abscess formation. There was no mammographic evidence of malignancy. Microscopic examination of a core biopsy showed acute inflammatory changes and intra-and extracellular grampositive organisms. The peripheral white blood cell count remained normal, a human immunodeficiency virus antibody test was negative, and immunoglobulin levels were normal. The histological diagnosis was granulomatous mastitis with no evidence of malignancy.Intravenous penicillin and flucloxacillin therapy was started, but this was changed to oral amoxicillin-clavulanate and metronidazole after 3 days. A further 3 days later, she was discharged from hospital taking oral doxycycline (100 mg daily) and oral clindamycin (150 mg 4 times a day), which was continued for 12 days. In the following 2 weeks, the area of inflammation enlarged and an abscess formed, requiring readmission to hospital. The abscess was incised, and approximately 10 ml of purulent material was drained. At this stage, she was recommenced on doxycycline (200 mg daily). Two further drainage procedures were required, after which the skin healed and the induration resolved, leaving a small palpable lesion thought to be scar tissue. Antibiotic therapy was stopped after 5 months of continuous treatment, but within 2 weeks pain returned and the abscess reformed.Of note in the patient's past medical history is a pituitary adenoma with galactorrhea detected 3 years before. This has been controlled with cabergoline. There was no history of prior breast abscess, breast implants, trauma to the breast, or other conditions that might predispose to breast abscess formation.Dry, crinkled, creamy-white colonies were seen on culture of pus aspirated at the time the abscess was first incised. A Gram stain could not be performed at this time, as there was an insufficient amount of specimen available. Morphologically similar colonies were identified from a follow-up swab taken 5 days after the lesion was first incised and from a swab and aspirate taken a further 5 days later. On this occasion, grampositive cocci were seen in the aspirated material with microscopy. After the second incision and drainage, cultures of three further wound swabs and one tissue specimen all grew the previously isolated organism. Coagulase-negative staphylococci were coisolated from two of the samples, but no other microorganisms were cultured.Upon nonstandardized susceptibility testing by disk diffusion, the organism was found ...

Breast abscess caused by Gordonia bronchialis and the use of 16s rRNA gene sequence analysis for its definitive identification

“…bronchialis, the species isolated in this case, was initially identified from samples of soil and sputum from patients with pulmonary disease (Conville & Witebsky, 2001;Johnson et al, 2011;Siddiqui et al, 2012). Only 13 cases of infection with this species of actinomycete have been described (Siddiqui et al, 2012), including a reported recurrent breast abscess in an immunocompetent patient with no previous medical history (Werno et al, 2005) that shared many features with our case. Another case of granulomatous mastitis in an immunocompetent patient caused by other species of Gordonia (Gordonia terrae) has also been reported, although the patient had a previous history of nipple piercing (Zardawi et al, 2004).…”

“…(Werno et al, 2005). Many patients, as in our case, require 6-12 weeks of therapy with different antibiotics, often along with appropriate surgical debridement (Johnson et al, 2011;Siddiqui et al, 2012;Sng et al, 2004;Werno et al, 2005).…”

“…Gordonia spp., previously classified within the genera Rhodococcus and Gordona, have been isolated from the environment and from the intestinal content of mammals (Conville & Witebsky, 2001). These organisms rarely cause disease in humans, although they have been isolated in infections from immunocompromised patients and, less frequently, from previously healthy persons (Siddiqui et al, 2012;Werno et al, 2005;Riegel et al, 1996). However, their true prevalence could be underestimated due to their fastidious growth requirements, slow growth in conventional cultures and confusing morphology.…”

“…This prolonged course could be explained by the ability of Gordonia spp. to form sessile communities where antimicrobial penetration is poor (Werno et al, 2005). There are no standardized recommendations for treatment of infections caused by Gordonia spp.…”

“…These organisms are emergent pathogens that have been isolated in infections from immunocompromised patients and, less frequently, from previously healthy individuals (Siddiqui et al, 2012;Werno et al, 2005;Riegel et al, 1996).…”