Lymphocyte depression as a predictor of postoperative intraabdominal abscess after appendectomy in children.
BACKGROUND
This study evaluated the efficacy of lymphopenia to predict postappendectomy intraabdominal abscess (IAA) in pediatric complex appendicitis.


METHODS
This single-center retrospective cohort study included appendectomy patients with complex appendicitis from 4/2012 to 10/2014. IAA was diagnosed based on imaging or undergoing a drainage procedure. Labs were used from the closest day prior to abscess diagnosis or day of discharge from index admission. Lymphocyte percentage was categorized based on age-specific cutoffs with lymphopenia defined as a low percentage. Comparisons were made using chi-square or Fisher exact tests for categorical variables and Mann-Whitney U-tests for continuous variables.


RESULTS
Of 611 appendectomy patients with complicated appendicitis, 551 had WBC and differential. IAA was identified in 79 (12.9%) patients. There were no significant differences in demographics between IAA and non-IAA groups. Patients with IAA had higher rates of leukocytosis (44.3% versus 12.3%, p<0.001) and higher rates of age-based lymphopenia (84% vs. 46%, p<0.001). IAA was independently associated with leukocytosis (OR 3.65, p<0.001) and lymphopenia (OR 4.46, p<0.001). Patients with leukocytosis and lymphopenia had the highest abscess rate (36%), and those with normal labs had the lowest (3%, p<0.001).


CONCLUSIONS
Lymphocyte depression is a useful adjunct to predict postoperative IAA in patients with complicated appendicitis.


METHODS
III.
Center for Surgical Outcomes Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH.
Daniel L
DL
Lodwick
Center for Surgical Outcomes Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH.
Jennifer N
JN
Cooper
Department of Pediatric Surgery, Nationwide Children's Hospital, Columbus, OH.
Brian
B
Kenney
Center for Surgical Outcomes Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH; Department of Pediatric Surgery, Nationwide Children's Hospital, Columbus, OH.
Katherine J
KJ
Deans
Center for Surgical Outcomes Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH; Department of Pediatric Surgery, Nationwide Children's Hospital, Columbus, OH.
Peter C
PC
Minneci
Department of Pediatric Surgery, Nationwide Children's Hospital, Columbus, OH. Electronic address: Rajan.thakkar@nationwidechildrens.org.
Rajan K
RK
Thakkar
D018784:Abdominal Abscess / Q000175:diagnosis / Q000209:etiology*; D000293:Adolescent; D001062:Appendectomy; D001064:Appendicitis / Q000601:surgery*; D002648:Child; D005260:Female; D006801:Humans; D008231:Lymphopenia / Q000150:complications* / Q000175:diagnosis; D008297:Male; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology*; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors
Abscess; Complicated appendicitis; Lymphopenia; Pediatric; Perforated appendicitis