A 61-yr-old man, born and raised in Crete, was admitted to our hospital with a 6-month history of diarrhea, weight loss of 7 kg, weakness, anorexia, low grade fever, and episodes of pain in the right lower abdominal quadrant. He did not reported arthralgias, rash, cough, or the presence of blood in his stools. There was no family history of inflammatory bowel disease or colon cancer. His past medical history included a diagnosis of hypothyoidism under treatment with thyroxine 100 mcg/d, and an episode of haemoptysis five years ago attributed to bronchiectasis. The patient had no past history of TB and was not aware of any TB exposure. He had been drinking alcohol (50-60 g/d) for 25 years, but stopped drinking five years ago. He did not smoke and worked as auxiliary staff in a community mental clinic.
Physical examination revealed mild abdominal tenderness, mostly confined to the right lower quadrant. The remainder of the examination was unremarkable. The laboratory workup showed a mild anaemia (Hb 11.5 g/dl, Hct 35.8%, MCV 68.1 fl), a serum ferritin of 7.71 (normal, 12-237 ng/ml) and a serum folate of 4.2 ng/ml (normal, 5.3-14.4 ng/ml). Liver biochemistries, total cholesterol, serum proteins, prothrombin time and thyroid hormones were within normal range. Serologic testing for HIV, Yersinia and E. histolytica were negative. Stool samples were negative for infectious organisms. A chest x-ray examination presented no significant findings.
Colonoscopy revealed a tumorous lesion in the ascending colon near the caecum. The colonoscope could not be introduced beyond the lesion. Initial endoscopic diagnosis was that of a malignant lesion, and multiple biopsies were obtained. Histology showed chronic inflammatory changes and noncaseating epithelioid granulomas, a pattern consistent with Crohn's disease. Esophagogastroduodenoscopy showed an axial hiatal hernia and a diffusely erythematous gastric mucosa. A small bowel series was normal. A tentative diagnosis of Crohn's disease was made and a treatment with Budesonide 9 mg/d and Mesalamine 3 g/d was initiated. However, no improvement was noticed and the diarrhea and fever rather deteriorated in the next days.
A CT-scan examination was performed to rule out an abdominal or pelvic abscess. The CT scan revealed a concentric wall thickening confined to the caecal-ascending colon border, luminal stenosis, extensive thickening of the mesenteric folds, the peritoneum and great omentum, small mesenteric lymph nodes, and a small amount of high density peritoneal fluid (Figures 1 and 2). CT findings were not consistent with Crohn's disease and raised the possibility of TB involvement. Tuberculin test was negative. A thoracic CT revealed nodular and fibrotic changes in the apical segments of the upper lobes, a pattern consistent with past TB exposure. Bronchoscopy was normal and acid-fast bacilli were not detected in the sputum, bronchoalveolar lavage or gastric aspirate. In view of our failure to confirm the diagnosis of colonic TB, a second colonoscopy was planned to obtain new biopsy specimens for culture and PCR analysis. When however the biopsies from the tumorous lesion were reevaluated and appropriately stained to look for acid-fast rods, several tubercle bacilli were identified upon Zielh-Neelsen staining. The patient was treated with Rifampicin (10 mg/kg/d), Isoniazid (5 mg/kg/d), Pyrazinamide (30 mg/kg/d) and Ethambutol (15 mg/kg/d). Over the next 10 days, the patient became afebrile, the stools were formed, at a frequency of 2-3 times per day, and he was subsequently discharged from the hospital in good condition. The patient was seen 2 months after discharge at which time he had gained weight and he was asymptomatic. Colonoscopy revealed a normal appearing caecal mucosa. Currently, six months after diagnosis, the patient is free of symptoms and is continuing the anti-tuberculous treatment.