| Intra-abdominal infection | |
|---|---|
| Specialty | Gastroenterology |
Intra-abdominal infection (IAI, also spelledintraabdominal) is a group ofinfections that occur within theabdominal cavity. They vary fromappendicitis tofecal peritonitis.[1] Risk of death despite treatment is often high.[1]
IAIs can be classified into uncomplicated and complicated infections. Uncomplicated infections often involved the infection of single organ and can be controlled by surgical removal of the source of infection, and antibiotics is not required after the surgery to control the infection. In complicated infections, the infection spread to a part or to the whole of theperitoneum, causingperitonitis. Meanwhile, peritonitis can be classified into primary, secondary, and tertiary peritonitis. Primary peritonitis is the diffuse bacterial infection of the peritoneum while the integrity of the gastrointestinal tract is preserved (in cases ofascites); secondary peritonitis is the infection of peritoneum where the integrity of gastrointestinal tract is compromised; tertiary peritonitis is reinfection of peritoneum 48 hours after apparently good surgical control of secondary peritonitis.[2]
Those with suspected IAIs usually have acute onset of abdominal pain with signs of local or generalisedinflammations such as pain,tenderness (pain on touching), fever,tachycardia (increased heart rate), ortachypnea (increased breathing rate). In more severe cases, such as organ failure, signs such ashypotension (low blood pressure),oliguria (reduced urine output), sudden onset ofaltered level of consciousness, andlactic acidosis will appear.[2]
In case ofappendicitis, signs such as fever, positivepsoas sign, migration of pain from umbilicus to theright iliac fossa increases the likelihood of the disease; while signs such as vomiting before the pain reduces its likelihood to occur.[2]
CT scan and ultrasound has been used routinely to complete the assessment of IAIs. CT scan has higher sensitivity and specificity than ultrasound to access the condition. However, CT scan poses radiation risk to the subject.[2] MRI scan is less readily available than CT scan or ultrasound in hospitals to diagnose IAIs. However, it has been proposed to be used in those who are pregnant and have inconclusive findings on ultrasound. The sensitivity and specificity of MRI in diagnosing acute appendicitis are 94% and 96% respectively.[2]
Laparoscopic surgery has also been used to diagnose the cause of IAIs when imaging is unhelpful. Besides, the laparoscopic surgery can also initiate treatment in the same setting. The accuracy is very high, in the range of 86 to 100%.[2]