Leukocytosis after posttraumatic splenectomy: a physiologic event or sign of sepsis?

HYPOTHESIS Although elevations in white blood cell count (WBC) and platelet count (PC) after splenectomy for trauma constitute a physiologic event, certain WBC and PC patterns help differentiate patients with from those without sepsis. DESIGN Medical record and trauma registry record retrospective review. SETTING Academic level I trauma center. PATIENTS From February 1997 through May 2001, 118 trauma patients underwent splenectomy. Sixty patients developed postoperative sepsis (pneumonia, abdominal infection, septicemia, or severe urinary tract infection) (septic group) and 58 did not (nonseptic group). MAIN OUTCOME MEASURES White blood cell count, PC, and PC/WBC. RESULTS After the fifth postoperative day, the WBC of patients with sepsis remained consistently greater than 15 x 10(3)/microL and the PC/WBC remained consistently less than 20. In patients without sepsis, these values remained less than 15 x 10(3)/microL and greater than 20, respectively. Stepwise regression analysis identified 3 independent predictors of sepsis: (1) day 5 PC/WBC less than 20, (2) Injury Severity Score greater than 16, and (3) day 5 WBC greater than 15 x 10(3)/microL. According to a statistical prediction model, the probability of sepsis when all 3 predictors were present was 97.4%; when all 3 were absent, it was 2.5%. CONCLUSIONS At and after the fifth postoperative day, a WBC greater than 15 x 10(3)/microL and a PC/WBC less than 20 are highly associated with sepsis and should not be considered as part of the physiologic response to splenectomy. In view of the seriousness of postsplenectomy sepsis, these values may be used to increase vigilance and prompt early aggressive treatment.