A colonoscopy is a medical procedure used to examine the inner lining of the large intestine, including the colon and rectum. A thin, flexible tube equipped with a camera, known as a colonoscope, is gently inserted through the anus and guided through the bowel. This allows healthcare providers to visualize the intestinal lining, detect abnormalities, and perform interventions such as polyp removal or tissue biopsies. While generally considered a safe and routine procedure, some individuals may experience a fever afterward.
Typical Post-Colonoscopy Body Responses
After a colonoscopy, it is common to experience some mild discomforts, such as bloating or abdominal cramps. These sensations often result from the air introduced into the colon during the examination to improve visualization. Small amounts of rectal bleeding may also occur, particularly if biopsies were taken or polyps removed, and this typically resolves within a day or two.
A low-grade fever, generally below 100.4°F (38°C), can sometimes be a transient reaction following any invasive medical procedure. This mild temperature elevation might be part of the body’s natural inflammatory response to the procedure itself, a slight irritation, or even an effect of the sedation administered. Such fevers are usually temporary, resolving within 24 to 72 hours, and often do not indicate a serious complication.
Fever as a Sign of Complication
While minor fevers are common, a higher temperature or fever accompanied by other symptoms can indicate a more serious, though less frequent, complication. Several distinct conditions can manifest with fever after a colonoscopy.
Post-polypectomy syndrome (PPS) can occur after polyps are removed using electrocautery during a colonoscopy. This condition involves a localized burn injury to the colon wall, causing inflammation, pain, and often fever. PPS mimics the symptoms of a colonic perforation but does not involve an actual tear in the bowel wall. Symptoms typically appear within 12 hours, but can be delayed up to 5-7 days after the procedure. Management typically involves supportive care, including intravenous fluids and pain relief, and does not generally require surgery.
Colonic perforation is a rare but serious complication where a tear develops in the colon wall. This tear allows bacteria and intestinal contents to leak into the abdominal cavity, causing peritonitis. Signs include high fever, severe or worsening abdominal pain, and rigidity of the abdomen. Perforation most commonly presents within 24 hours of the procedure, but delayed cases can occur. It requires immediate medical attention and often surgical repair.
Infections, distinct from perforation, can also cause fever. While uncommon, bacteria can sometimes enter the bloodstream during the procedure, or existing conditions like diverticulitis might be exacerbated. Symptoms of an infection can include abdominal pain, tenderness, and chills, in addition to fever.
Sedation medications used during the procedure can also rarely cause fever. While patients may feel tired or groggy, severe reactions like heart or breathing problems are possible.
Guidance on Seeking Medical Care
If concerning symptoms arise after a colonoscopy, contact the gastroenterologist who performed the procedure or seek emergency medical care immediately. This ensures potential complications are evaluated and addressed without delay.
Immediate medical attention is necessary for specific warning signs:
High fever, typically above 101°F (38.3°C), or persistent fever over 100.4°F (38°C).
Severe or worsening abdominal pain.
Abdominal rigidity or tenderness.
Persistent nausea or vomiting.
Significant rectal bleeding, especially if heavy or with blood clots.
Dizziness or fainting.