Clinical features of actinomycosis

Abstract

Actinomycosis is a rare heterogeneous anaerobic infection with misleading clinical presentations that delay diagnosis. A significant number of misdiagnosed cases have been reported in specific localizations, but studies including various forms of actinomycosis have rarely been published.We performed a multicenter retrospective chart review of laboratory-confirmed actinomycosis cases from January 2000 until January 2014. We described clinical characteristics, diagnostic procedures, differential diagnosis, and management of actinomycosis of clinical significance.Twenty-eight patients were included from 6 hospitals in France. Disease was diagnosed predominately in the abdomen/pelvis (n = 9), orocervicofacial (n = 5), cardiothoracic (n = 5), skeletal (n = 3), hematogenous (n = 3), soft tissue (n = 2), and intracranially (n = 1). Four patients (14%) were immunocompromised. In most cases (92 %), the diagnosis of actinomycosis was not suspected on admission, as clinical features were not specific. Diagnosis was obtained from either microbiology (50%, n = 14) or histopathology (42%, n = 12), or from both methods (7%, n = 2). Surgical biopsy was needed for definite diagnosis in 71% of cases (n = 20). Coinfection was found in 13 patients (46%), among which 3 patients were diagnosed from histologic criteria only. Two-thirds of patients were treated with amoxicillin. Median duration of antibiotics was 120 days (interquartile range 60–180), whereas the median follow-up time was 12 months (interquartile range 5.25–18). Two patients died.This study highlights the distinct and miscellaneous patterns of actinomycosis to prompt accurate diagnosis and earlier treatments, thus improving the outcome. Surgical biopsy should be performed when possible while raising histologist's and microbiologist's awareness of possible actinomycosis to enhance the chance of diagnosis and use specific molecular methods.

Pelvic Actinomycosis Masquerading as Malignancy

“…6 Actinomycosis often presents with vivid presentations that can mimic various etiologies like tuberculosis, nocardiasis, malignancies.…”

“…6 Pelvic actinomycosis can occur at any age and in a reported large cohort of 92 patients, the mean age at diagnosis was 37 years. 7 The presenting features usually include fever, pelvic pain or the incidental findings of suspicious pelvic masses on imaging.…”

Actinomyces neuii infection following ovarian cystectomy

“…[2] Coinfection with other organisms is common and contributes to the pathogenesis. [1] Actinomycosis, a chronic granulomatous disease, occurs most frequently in the orocervicofacial regions (50%-60%), but may also occur in the abdomen, thorax or in the pelvis related to intrauterine contraceptive devices (IUDs). [1,2] The most common Actinomyces is Actinomyces israelii, but several others have been described through the use of biochemical assays.…”

“…[1] Actinomycosis, a chronic granulomatous disease, occurs most frequently in the orocervicofacial regions (50%-60%), but may also occur in the abdomen, thorax or in the pelvis related to intrauterine contraceptive devices (IUDs). [1,2] The most common Actinomyces is Actinomyces israelii, but several others have been described through the use of biochemical assays. [3] Actinomyces neuii, a species of Actinomyces, was first described in 1994 by Funke et al [4,5] In contrast to other species of Actinomyces, it is a diphtheroidal organism without branching, has both anaerobic and aerobic growth, and has greater than 60 strains.…”

“…are gram positive, filamentous anaerobic bacteria, characterized by pigment-producing rods forming filamentous branches. [1] Actinomyces form a component of the intestinal commensal flora and vaginal flora, and are generally not pathogenic. However, infections occur through a breach in an anatomic barrier, leading to abscess formation, sinus tracts, or fistulas with a characteristic release of "sulphur granules" resulting in a pungent odor.…”