A 63 year old man presents with acute onset pain that is mostly localized in left lower quadrant. He has fever, chills, nausea, and vomiting. Physical exam reveals rebound tenderness, involuntary guarding, and board-like rigidity. There is a tender, firm, and fixed abdominal mass.
Labs: Gram negative rods found on blood agar plates grown anaerobically containing kanamycin and vancomycin.
Discussion: The diagnosis of diverticulitis is made by clinical presentation. The determination of the organism can be made by culture. Diverticula of the colon are herniations of the mucosa and submucosa through the circular muscular layer. Diverticulitis is an infection of the diverticula. Bacteroides fragilis is the most common cause of serious anaerobic infections such as diverticulitis.
Other causes of diverticulitis are members of the Enterobacteriaceae family. Members of the Enterobacteriaceae family include Escherichia, Shigella, Salmonella, Klebsiella, Enterobacter, Serratia, Proteus, and Yersinia.
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