Actinomycosis (abdominal)

Abdominopelvic actinomycosis accounts for about 20% of cases.

Predisposing factors include:

• acute appendicitis (particularly with perforation) - account for most (65%) cases and can present with a right iliac fossa mass
• gastrointestinal perforation
• previous surgery
• neoplasia
• foreign bodies in the gastrointestinal tract or genitourinary tract, with or without erosion through the mucosal barrier

Patients may present with non specific symptoms such as fever, weight loss, and abdominal pain.

• a hard fibrous mass, honey-combed with abscess cavities, develops in the right iliac fossa but may not always be palpable
• multiple sinuses may appear on the abdominal wall or the perianal region

Spread may occur via the portal vein producing a portal pyaemia, the liver being riddled with abscess cavities. Spread to all abdominal viscera may occur.

Although pelvic actinomycosis is predominantly associated with IUCD, abdominal disease spreading to the pelvic may result in pelvic actinomycosis (1).

Reference:

• (1) Wong VK, Turmezei TD, Weston VC. Actinomycosis. BMJ. 2011;343:d6099