The abdomen as a source of occult sepsis.

When a patient presents with sepsis and no clear etiology, the abdomen can hide a focus of infection and must be considered in the course of the evaluation (Fig. 1). There are certain groups of patients who do not exhibit the usual signs and symptoms of intra-abdominal infection and therefore constitute the population at risk for occult abdominal sepsis. These patients, for one reason or another, have an unreliable history or physical exam. Once intra-abdominal infection is suspected, certain basic laboratory and radiographic evaluations should be undertaken. Treatment delays are not tolerated and the performance of diagnostic tests when a laparotomy appears inevitable is not indicated. CT of the abdomen should not be used as a screening exam and should be reserved for those cases potentially having an infected fluid collection. If a thorough evaluation of the abdomen reveals a possible source, a measured medical and surgical approach can be undertaken, depending on the etiology. If no source is found, the question of a diagnostic laparotomy arises in certain cases (Fig. 2). This procedure should be reserved for those patients having some type of underlying abdominal surgery or pathology. Without a previous history of abdominal surgery or pathology, and with no other clinical evidence of intra-abdominal infection, a nondirected laparotomy can be safely performed when organ failure is not present but usually will not reveal a treatable lesion. Multiple organ failure may indicate the presence of a hidden abdominal source of infection; however, the window for successful surgical intervention may have already passed. Multiple organ failure does not mandate laparotomy when there is no clinical or radiographic basis for suspecting an abdominal source of infection. This is especially true if an alternative source of sepsis has been defined.