History: A 20 lb pig of unknown age had a history of diarrhea. (Thats all we know)
Gross Lesions:
The ileum and distal jejunum were diffusely thickened, with a cobblestoned appearance to the serosa and corrugated mucosa which was covered in a moderate amount of green to yellow fibrin. The serosal surface of the colon had multiple focal pale grey nodules protruding from the surface.
(sorry no pictures)
Histopathology:
Ileum: There is marked superficial necrosis of the mucosa with abundant fibrin accumulation on the mucosal surface. Crypts are multifocally dilated with neutrophils and cellular debris. Warthan-Starry silver stain was positive for intracellular curved bacteria in the apical enterocyte cytoplasm (Lawsonia intracellularis).
Ileum- mucosal hyperplasia with crypt abscesses
The mucosal epithelium is hyperplastic lined by pseudostratified columnar cells and crypts occasionally herniate into the submucosa.
Ileum- branching and dividing crypts
The crypts are often branched and there are moderate numbers of neutrophils and macrophages in the lamina propria.
Ileum- Warthin Starry silver stain with intracellular bacteria
Lawsonia are intracellular bacteria that reside usually in the apical cytoplasm.
Ileum- Warthin-Starry silver stain showing bacteria in the apical cytoplasm of enterocytes
Morphologic Diagnosis:
Ileum: Fibrino-necrotic ileitis, moderate, multifocal, pyogranulomatous, with mucosal hyperplasia and intracellular bacteria consistent with Lawsonia intracellularis
Filed under: Necropsy Cases | Tagged: Gastrointestinal, Bacteria, Porcine
