Intestinal perforation is one of the severe complications of typhoid fever. Although its incidence is low, its mortality rate remains relatively high.
Etiology and Pathology
Typhoid fever is caused by Salmonella typhi, which invades the lymphoid follicles and Peyer’s patches of the terminal ileum after oral ingestion. This leads to inflammatory edema, and by the second week of illness, necrosis begins to develop, resulting in ulcer formation. These ulcers are longitudinal, with their long axis parallel to the intestinal lumen. The ulcers typically affect the submucosa but can extend to the muscular and serosal layers in severe cases. Increased intraluminal pressure may subsequently lead to acute perforation. The perforations are usually not contained, resulting in acute, diffuse peritonitis. About 80% of perforations occur in the terminal ileum within 50 cm of the ileocecal valve, and most of these are solitary.
Clinical Presentation and Diagnosis
In patients already diagnosed with typhoid fever, sudden onset of pain in the right lower abdomen that rapidly spreads throughout the abdomen, accompanied by vomiting and abdominal distension, may indicate intestinal perforation. Although typhoid fever is commonly associated with a slow pulse, leukopenia, and persistent high fever, the occurrence of perforation is marked by tachycardia, leukocytosis, and a sudden drop in body temperature. A physical examination would typically reveal marked abdominal tenderness, absent bowel sounds, and other signs of peritonitis. X-ray imaging may show free air in the abdominal cavity. Abdominal paracentesis may yield purulent fluid, which can be used for Salmonella typhi culture, along with blood cultures or the Widal test for a definitive diagnosis.
Attention should also be given to a subset of patients who have no typical history of typhoid fever and present only with mild symptoms such as low-grade fever, headache, and general malaise. This presentation is sometimes referred to as "ambulatory typhoid." In these cases, when perforation occurs, it presents as acute right lower abdominal pain with signs of acute peritonitis, and the condition is often misdiagnosed as perforated appendicitis. Surgical exploration may reveal perforation of the terminal ileum with surrounding inflammation of the appendix but no appendiceal perforation. Differential diagnosis of intestinal typhoid perforation and appendiceal perforation should be considered in regions and seasons where typhoid fever is prevalent.
Treatment
Once intestinal typhoid perforation is confirmed, urgent surgical treatment is required. Given the typically debilitated condition of these patients, simple and rapid perforation repair is generally the preferred approach. In cases involving multiple perforations or severe, uncontrollable intestinal bleeding, and where the patient's overall condition permits, intestinal resection with anastomosis or stoma creation may be considered.
Postoperative care focuses on supportive therapy and aggressive antimicrobial treatments. Effective antibiotics for Salmonella typhi include fluoroquinolones, third-generation cephalosporins, ampicillin, or amoxicillin, all of which have demonstrated reliable efficacy.