Objectives: This study aimed to characterize the time course of white blood cell (WBC) count normalization in patients with isolated blunt head trauma and to examine whether this time course differs by injury severity (Glasgow Coma Scale, GCS) or computed tomography (CT) findings.

Methods: We conducted a prospective cohort study of 173 adult patients with blunt head trauma presenting to the surgical emergency department of Al-Zahra University Hospital, Isfahan, Iran, in 2020. WBC counts were measured at admission and every 8 hours for the first 48 hours, then daily until normalization or discharge. Normalization was defined as the first WBC value within the laboratory reference range (4,400–11,000/mm³), confirmed on the subsequent measurement. Time to normalization was compared across GCS and CT-finding categories using the Kaplan-Meier method and log-rank test. Categorical comparisons used the chi-square or Fisher's exact test. Data were analyzed in SPSS v22.

Results: At admission, 60% of patients (n=104) had leukocytosis, 38% (n=67) had a normal WBC count, and 1% (n=2) had leukopenia. Mean WBC count at admission was 12,564.18/mm³ (95% CI 11,915.77–13,212.85) and was significantly higher in men than women (P=0.011). Among the 104 patients with leukocytosis WBC counts at admission, the mean time to normalization was 2.32 days (95% CI 1.98–2.65) and did not differ significantly by CT finding (P=0.614) or GCS category (P=0.111).

Conclusion: In patients with isolated blunt head trauma and no clinical evidence of infection, trauma-related leukocytosis generally resolved within approximately three days, regardless of GCS category or CT findings.