Consider Cormorbidities in Abdominal Infections

SARASOTA, FLA. — Preexisting conditions may be better predictors of the outcomes of intra-abdominal infections than are the source or type of infection, according to a single-center, retrospective study.

The results suggest that interventions for intra-abdominal infections (IAIs) should focus on treating the burden of chronic disease in patients rather than on preventing specific sources or types of IAIs, Tazo Inui said at the annual meeting of the Central Surgical Association.

Community-acquired IAIs (CIAIs) tend to occur most frequently with complicated appendicitis, but nosocomial IAIs (NIAIs) have been reported to have worse outcomes, said Mr. Inui, a fourth-year medical student at Case Western Reserve University, Cleveland.

In a review of 452 patients with IAIs during 1999-2007 at MetroHealth Medical Center, Cleveland, Mr. Inui and his associates, led by Dr. Mark Malagoni, compared 234 patients with a CIAI and 218 with an NIAI. An NIAI was defined as an infection diagnosed 48 hours or more after admission for an unrelated diagnosis or within 4 weeks of an operation or intervention for an IAI.

The investigators reviewed patients' scores on the Charlson Comorbidity Index, which is designed to predict mortality based on the burden of a patient's comorbid disease, as well as their multiorgan dysfunction (MOD) score, which is intended to measure dysfunction in six organ systems and has been shown to correlate strongly with mortality, particularly in ICU patients, Mr. Inui said.

Patients with CIAI most often presented with complicated appendicitis (52%), followed by colonic (26%) or small bowel (11%) sources of infection. NIAIs were associated most frequently with postoperative infection (44%), then colonic (29%) or small bowel sources (17%). NIAI patients also were significantly older than those with CIAI (53 vs. 50 years).

Patients were excluded from the study if they had been treated within 24 hours for a gastroduodenal perforation or within 12 hours for a traumatic intestinal perforation.

The investigators found that the 122 CIAI patients with complicated appendicitis were younger, had lower Charlson scores, and had lower preoperative MOD scores than did CIAI patients without complicated appendicitis. However, when they excluded CIAI patients with complicated appendicitis from the analysis, there were no differences in preoperative characteristics between NIAI patients and CIAI patients without appendicitis.

Mr. Inui and his colleagues excluded patients with complicated appendicitis from further analyses because no one with that condition died, and only 7% of such patients required reintervention (surgery or percutaneous drainage).

Thus, among patients without appendicitis in the CIAI and NIAI groups, comparable rates of treatment failure—defined as death (8% vs. 9%, respectively) or the need for reintervention (21% vs. 21%)—and postoperative complications were seen.

“This observation suggests that patients with community-acquired and nosocomial infections are, in fact, more alike than previously reported,” Mr. Inui said.

Mortality was independently predicted by the presence of catheter-related bloodstream infections, postoperative myocardial infarctions or arrhythmias, and an age of 65 years or older.

Even though Charlson scores of 2 or higher did not independently predict mortality, Mr. Inui noted that there was a stepwise increase in mortality according to Charlson score, such that mortality was less than 5% in patients with a score of 0, 10% with a score of 1-2, 12% with a score of 3-4, and 20% with a score of 5 or higher.

However, when patients with appendicitis were included in the analysis, treatment failure was independently associated with a nonappendiceal source of infection and a Charlson score of 2 or greater. Reintervention also was independently associated with a nonappendiceal source of infection, as well as a MOD score of 4 or greater on postoperative day 7.

Mr. Inui noted that he and his coinvestigators did not evaluate the results of cultures or the attempts to control the sources of infection.

SARASOTA, FLA. — Preexisting conditions may be better predictors of the outcomes of intra-abdominal infections than are the source or type of infection, according to a single-center, retrospective study.

The results suggest that interventions for intra-abdominal infections (IAIs) should focus on treating the burden of chronic disease in patients rather than on preventing specific sources or types of IAIs, Tazo Inui said at the annual meeting of the Central Surgical Association.

Community-acquired IAIs (CIAIs) tend to occur most frequently with complicated appendicitis, but nosocomial IAIs (NIAIs) have been reported to have worse outcomes, said Mr. Inui, a fourth-year medical student at Case Western Reserve University, Cleveland.

In a review of 452 patients with IAIs during 1999-2007 at MetroHealth Medical Center, Cleveland, Mr. Inui and his associates, led by Dr. Mark Malagoni, compared 234 patients with a CIAI and 218 with an NIAI. An NIAI was defined as an infection diagnosed 48 hours or more after admission for an unrelated diagnosis or within 4 weeks of an operation or intervention for an IAI.

The investigators reviewed patients' scores on the Charlson Comorbidity Index, which is designed to predict mortality based on the burden of a patient's comorbid disease, as well as their multiorgan dysfunction (MOD) score, which is intended to measure dysfunction in six organ systems and has been shown to correlate strongly with mortality, particularly in ICU patients, Mr. Inui said.

Patients with CIAI most often presented with complicated appendicitis (52%), followed by colonic (26%) or small bowel (11%) sources of infection. NIAIs were associated most frequently with postoperative infection (44%), then colonic (29%) or small bowel sources (17%). NIAI patients also were significantly older than those with CIAI (53 vs. 50 years).

Patients were excluded from the study if they had been treated within 24 hours for a gastroduodenal perforation or within 12 hours for a traumatic intestinal perforation.

The investigators found that the 122 CIAI patients with complicated appendicitis were younger, had lower Charlson scores, and had lower preoperative MOD scores than did CIAI patients without complicated appendicitis. However, when they excluded CIAI patients with complicated appendicitis from the analysis, there were no differences in preoperative characteristics between NIAI patients and CIAI patients without appendicitis.

Mr. Inui and his colleagues excluded patients with complicated appendicitis from further analyses because no one with that condition died, and only 7% of such patients required reintervention (surgery or percutaneous drainage).

Thus, among patients without appendicitis in the CIAI and NIAI groups, comparable rates of treatment failure—defined as death (8% vs. 9%, respectively) or the need for reintervention (21% vs. 21%)—and postoperative complications were seen.

“This observation suggests that patients with community-acquired and nosocomial infections are, in fact, more alike than previously reported,” Mr. Inui said.

Mortality was independently predicted by the presence of catheter-related bloodstream infections, postoperative myocardial infarctions or arrhythmias, and an age of 65 years or older.

Even though Charlson scores of 2 or higher did not independently predict mortality, Mr. Inui noted that there was a stepwise increase in mortality according to Charlson score, such that mortality was less than 5% in patients with a score of 0, 10% with a score of 1-2, 12% with a score of 3-4, and 20% with a score of 5 or higher.

However, when patients with appendicitis were included in the analysis, treatment failure was independently associated with a nonappendiceal source of infection and a Charlson score of 2 or greater. Reintervention also was independently associated with a nonappendiceal source of infection, as well as a MOD score of 4 or greater on postoperative day 7.

Mr. Inui noted that he and his coinvestigators did not evaluate the results of cultures or the attempts to control the sources of infection.

SARASOTA, FLA. — Preexisting conditions may be better predictors of the outcomes of intra-abdominal infections than are the source or type of infection, according to a single-center, retrospective study.

The results suggest that interventions for intra-abdominal infections (IAIs) should focus on treating the burden of chronic disease in patients rather than on preventing specific sources or types of IAIs, Tazo Inui said at the annual meeting of the Central Surgical Association.

Community-acquired IAIs (CIAIs) tend to occur most frequently with complicated appendicitis, but nosocomial IAIs (NIAIs) have been reported to have worse outcomes, said Mr. Inui, a fourth-year medical student at Case Western Reserve University, Cleveland.

In a review of 452 patients with IAIs during 1999-2007 at MetroHealth Medical Center, Cleveland, Mr. Inui and his associates, led by Dr. Mark Malagoni, compared 234 patients with a CIAI and 218 with an NIAI. An NIAI was defined as an infection diagnosed 48 hours or more after admission for an unrelated diagnosis or within 4 weeks of an operation or intervention for an IAI.

The investigators reviewed patients' scores on the Charlson Comorbidity Index, which is designed to predict mortality based on the burden of a patient's comorbid disease, as well as their multiorgan dysfunction (MOD) score, which is intended to measure dysfunction in six organ systems and has been shown to correlate strongly with mortality, particularly in ICU patients, Mr. Inui said.

Patients with CIAI most often presented with complicated appendicitis (52%), followed by colonic (26%) or small bowel (11%) sources of infection. NIAIs were associated most frequently with postoperative infection (44%), then colonic (29%) or small bowel sources (17%). NIAI patients also were significantly older than those with CIAI (53 vs. 50 years).

Patients were excluded from the study if they had been treated within 24 hours for a gastroduodenal perforation or within 12 hours for a traumatic intestinal perforation.

The investigators found that the 122 CIAI patients with complicated appendicitis were younger, had lower Charlson scores, and had lower preoperative MOD scores than did CIAI patients without complicated appendicitis. However, when they excluded CIAI patients with complicated appendicitis from the analysis, there were no differences in preoperative characteristics between NIAI patients and CIAI patients without appendicitis.

Mr. Inui and his colleagues excluded patients with complicated appendicitis from further analyses because no one with that condition died, and only 7% of such patients required reintervention (surgery or percutaneous drainage).

Thus, among patients without appendicitis in the CIAI and NIAI groups, comparable rates of treatment failure—defined as death (8% vs. 9%, respectively) or the need for reintervention (21% vs. 21%)—and postoperative complications were seen.

“This observation suggests that patients with community-acquired and nosocomial infections are, in fact, more alike than previously reported,” Mr. Inui said.

Mortality was independently predicted by the presence of catheter-related bloodstream infections, postoperative myocardial infarctions or arrhythmias, and an age of 65 years or older.

Even though Charlson scores of 2 or higher did not independently predict mortality, Mr. Inui noted that there was a stepwise increase in mortality according to Charlson score, such that mortality was less than 5% in patients with a score of 0, 10% with a score of 1-2, 12% with a score of 3-4, and 20% with a score of 5 or higher.

However, when patients with appendicitis were included in the analysis, treatment failure was independently associated with a nonappendiceal source of infection and a Charlson score of 2 or greater. Reintervention also was independently associated with a nonappendiceal source of infection, as well as a MOD score of 4 or greater on postoperative day 7.

Mr. Inui noted that he and his coinvestigators did not evaluate the results of cultures or the attempts to control the sources of infection.