Small-bowel obstruction caused by tuberculous strictures in an infant.

Abstract

Tuberculous enteritis is an unusual illness in children. Strictures causing obstruction are uncommon. We report a case of miliary tuberculosis (TB) with complicating small intestinal obstruction. In the discussion that follows, we review briefly the current knowledge on this form of TB. CASE REPORT An 11-month-old Pakistani boy was admitted with a 3-week history of intermittent fever and poor feeding. He had come to the United Kingdom, accompanying his mother, at the age of 5 months. She became ill with abdominal TB 2 months after arrival. Her sputum smear was initially negative, and so the child was not given chemoprophylaxis (M. tuberculosis was later grown from it). His initial tuberculin test was negative. Bacille Calmette-Guérin (BCG) was due to be given the day he was admitted. On admission, he was febrile and had a clear chest and a soft abdomen. Chest radiograph revealed miliary shadowing. Gastric lavage demonstrated scanty acid-fast bacilli (AFB), which were also present in his stools. A diagnosis of pulmonary TB was made at that stage; he was given triple chemotherapy (isoniazid, rifampicin, and pyrazinamide) and sent home, 11 days after admission. He was readmitted 2 weeks later with abdominal distention and persistent bilious vomiting. Barium follow-through demonstrated a distal jejunal obstruction. At laparotomy, there were multiple small-bowel strictures in ileum and proximal jejunum. Excision of part of the ileum was undertaken with end-to-end anastomosis and multiple stricturoplasty. The resected intestinal tissue had granulomata throughout the wall thickness, and many AFBs were seen, although the culture was negative. Postoperatively, he required intravenous nutrition for 10 days and was well enough to go home 20 days after his operation. DISCUSSION Abdominal tuberculosis is commonly a disease of young adults in the third and fourth decades of life and is largely restricted to developing countries. It is uncommon in children. Narasimharao (1) reported 56 cases only, over a period of 15 years. Involvement of the gastrointestinal tract was not uncommon world-wide, especially in adults, until the 1950s when, with pasteurisation of milk, better hygiene, and early treatment of pulmonary disease, it became unusual in developed countries. The human strain of mycobacteria is responsible for most cases today, but coexistent evidence of pulmonary TB is present in as few as 15-20% of cases (2). The disease may affect any part of the digestive system from mouth to anus but most commonly the terminal ileum and caecum. The fatty capsule of the bacillus protects it from acid digestion, and as they have a predilection for lymphoid tissue, bacteria tend to localise in this region. Intestinal TB can manifest itself as an acute or subacute obstruction that settles conservatively. Strictures of the small bowel that may be associated with obstruction are uncommon, and among 80 children with abdominal TB, only five had intestinal strictures (3). A definite diagnosis of intestinal TB requires histologic, with or without, microbiologic evidence of intestinal involvement. In practice, this is difficult except in those who have undergone laparotomy. The best way of obtaining histologic evidence is by laparoscopy, which is the investigation of choice in those who are nonobstructed. Percutaneous needle biopsy is helpful if there is associated peritoneal disease. Not infrequently, therefore, the diagnosis rests on characteristic clinical and barium contrast study findings. Treatment requires nutritional support, chemotherapy, and dealing with complications. Mortality has decreased from 50 to 3% with the introduction of anti-TB drugs and supportive nutritional therapy. Factors that still contribute to the death of patients include complications, late presentation, and delay in institution of specific therapy. If the small bowel is seriously affected, parenteral nutrition may be needed. Surgery has a definite place as a diagnostic procedure (to obtain histologic specimens and material for culture) and for the treatment of acute complications. Resection is required only if there is mechanical obstruction. There are a few lessons to be learnt from this case. Small intestinal obstruction due to TB is unusual in infancy and is rarely seen in the West. It therefore needs to be considered in the differential diagnosis of children with signs of intestinal obstruction when there is a family history of TB, and particularly in families from the Asian subcontinent. Tuberculin test took a few weeks before it became positive, and the child was about to have BCG when his symptoms precipitated the first admission. The case also highlights the practical difficulty in giving medications orally in a child with persistent vomiting. Laparotomy was done when our patient showed signs of bowel obstruction and only then was a definite diagnosis of intestinal TB made.