Pelvic actinomycosis

Pelvic actinomycosis infection is rare but serious infection caused by Actinomyces sp, an opportunistic gram-positive bacteria usually introduced by foreign bodies specially IUCDs, surgery, or trauma. It generally falls under the broader spectrum of pelvic inflammatory disease.

Pathology

Pelvic infection from several actinomyces sp can occur, which include:

• Actinomyces israelii: by far the commonest causative organism ³
• Actinomyces naeslundii
• Actinomyces viscosus
• Actinomyces eriksonii

The organisms are indigenous in the oral cavity, gastrointestinal tract, and genital tract, with opportunistic infection occurring when the mucosal barrier is broken.

Associations

• placement of intra-uterine contraceptive devices: usually when it has been present for a prolonged period
  • approximately 25% of IUCDs eventually get colonised  by actinomycosis
  • 2-4% of IUCDs that are colonised ultimately develop a serious actinomycotic infection

Radiographic features

Actinomycosis infection can mimic many other pelvic pathologies on imaging. The spread of infective/inflammatory change across tissue planes, and in particular retroperitoneal extension into the psoas muscle may suggest towards the diagnosis. MostThe most common site of involvement inof the GI system is iliocaecalthe ileocaecal junction.

Other findings:

• indurated pelvic fat
• pelvic free fluid 
• pelvic abscess
• hydronephrosis

Complications

• wider Intraintra-abdominal extension: mainly through contiguous spread
• formation of tubo-ovarian abscesses ²
• subsequent infertility

Treatment and prognosis

Treatment is usually with IV Penicillinpenicillin in uncomplicated cases. The presence of an associated complication such as a tubo-ovarian abscess would warrant surgical intervention.

Differential diagnosis

Due to its non specific-specific imaging appearances, pelvic actinomyces infectionactinomycosis can mimic several pathology such as:

• other forms of pelvic inflammatory disease
  • tuberculous pelvic inflammatory disease
• pelvic malignancy
  • ovarian cancers: as a general rule, may incite more ascites and lymphanopathy ^reflymphadenopathy