title: Retroperitoneal actinomycosis masquerading as inflammatory pseudotumor.
abstract: Inflammatory pseudotumors present clinically as mass lesions and microscopically show a spectrum of nonspecific inflammatory and regenerative changes. When the mesentery or retroperitoneum are involved, differentiation from inflammatory fibrosarcoma poses a diagnostic problem. The authors report on a 7-year-old boy who presented with fever, anemia, weight loss, and a retroperitoneal mass. Needle biopsy results of the mass showed features consistent with inflammatory pseudotumor. Examination of the resected mass showed actinomycosis.
authors.affiliation: Department of Pathology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Radhi
authors.forename: N
authors.initials: N
authors.lastname: Hadjis
authors.forename: L
authors.initials: L
authors.lastname: Anderson
authors.forename: B
authors.initials: B
authors.lastname: Burbridge
authors.forename: K
authors.initials: K
authors.lastname: Ali
mesh_terms: D000196:Actinomycosis / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D003937:Diagnosis, Differential; D005354:Fibrosarcoma / Q000175:diagnosis*; D006104:Granuloma, Plasma Cell / Q000175:diagnosis*; D006801:Humans; D008297:Male; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis*; D012187:Retroperitoneal Space