Influence of histamine receptor antagonists on the outcome of perforated appendicitis: analysis from a prospective trial.
OBJECTIVE
Diphenhydramine blocks the H(1) receptor to treat pruritus or to induce sleep, while ranitidine blocks the H(2) receptor to suppress gastric acid. They are often given to ill patients, such as those with perforated appendicitis. However, these receptors are integral to the inflammatory response, and to our knowledge, the impact of H(1) or H(2) blockade on outcome in the setting of perforated appendicitis has never been evaluated.


METHODS
Prospective randomized trial.


METHODS
Referral center.


METHODS
Children undergoing an operation for perforated appendicitis from April 2005 to November 2006.


METHODS
We conducted multivariate analysis with Pearson correlation on data from a prospective randomized trial comparing antibiotic regimen after appendectomy for perforated appendicitis and outcome. Medications with a significant correlation to abscess development were investigated by comparing those receiving the medication with those who did not using the t test for continuous variables and chi(2) test for discrete variables. Significance was defined as P < or = .05.


RESULTS
Significant correlations were found between the use of ranitidine (P = .05) or diphenhydramine (P = .03) and the development of an abscess. Direct comparison found no differences in patient or operative variables in those given either medication compared with those receiving no doses. Abscess rate in those receiving neither medication (n = 41) was 10%. Those given only ranitidine (n = 24) or diphenhydramine (n = 17) had doubled abscess rates of 17% and 18%, respectively. Those given both medications (n = 16) had a quadrupled abscess rate of 44% (P = .03).


CONCLUSIONS
Ranitidine or diphenhydramine given to patients with perforated appendicitis may increase the risk of postoperative abscess. Therefore, these medications should not be used empirically in this population.
Center for Prospective Clinical Trials, Department of Surgery, Children's Mercy Hospital, 2401 Gillham Road, Kansas City, MO 64108, USA. sspeter@cmh.edu
Shawn D
SD
St Peter
Susan W
SW
Sharp
Daniel J
DJ
Ostlie
D018784:Abdominal Abscess / Q000453:epidemiology*; D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001064:Appendicitis / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D004155:Diphenhydramine / Q000627:therapeutic use; D005260:Female; D006634:Histamine H1 Antagonists / Q000627:therapeutic use*; D006635:Histamine H2 Antagonists / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011899:Ranitidine / Q000627:therapeutic use; D013530:Surgical Wound Infection / Q000453:epidemiology*; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D011899:Ranitidine; D004155:Diphenhydramine