What is the Cause of this Mechanic’s Abdominal Pain?
A 56-year-old male auto mechanic experienced fever, chills, drenching night sweats, malaise, nausea, and abdominal pain and distention for 6 weeks, associated with 15 kg of lost weight. Twenty years ago he was diagnosed with ileocolonic Crohn’s disease, but he had been asymptomatic on mercaptopurine therapy for the past 10 years. He stopped smoking 20 years ago.
Upon physical examination, he had mild pallor and a distended, soft abdomen, which was mildly tender. He did not have jaundice, and there was no distinct palpable mass or evidence of ascites.
Laboratory tests revealed hemoglobin, 8.5 g/dL; mean corpuscular volume, 98; platelets, 790 × 109/L; erythrocyte sedimentation rate, 134; International Normalized Ratio, 1.8; total protein, 5.6 g/dL; and albumin, 1.8 g/dL. Levels of lectrolytes, creatinine, and liver enzymes were otherwise normal.
Computed tomography images of the abdomen and pelvis are shown in panels A and B.
CT-guided biopsy was performed and the pathology results are shown in panels C and D.