Patient presents with leukocytosis, unspecified (R70.8).  Elevated white blood cell count (WBC) was noted on routine laboratory testing or as part of a workup for [mention reason for testing, e.g., fever, infection symptoms, fatigue].  Complete blood count (CBC) demonstrates WBC of [insert value] x 10^9L.  Differential shows [describe differential, e.g., neutrophilia, lymphocytosis, etc. If differential is unavailable, state "Differential unavailable"].  Patient's clinical presentation includes [describe symptoms, e.g., asymptomatic, fever, chills, localized infection signs, fatigue, malaise, weight loss, night sweats].  Physical examination findings include [document relevant findings, e.g., normal, lymphadenopathy, hepatosplenomegaly, signs of infection].  At this time, the etiology of the leukocytosis is undetermined.  Differential diagnosis includes infection, inflammation, hematologic malignancy, medication effect, stress, and smoking.  Plan includes further investigation to identify the underlying cause of the elevated WBC.  Ordered tests include [list ordered tests, e.g., peripheral blood smear review, repeat CBC with differential, blood cultures if indicated, comprehensive metabolic panel (CMP), inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), imaging studies as clinically indicated, referral to hematology if warranted].  Patient education provided regarding leukocytosis, possible causes, and the importance of follow-up. Return visit scheduled for [date or timeframe] to review results and discuss further management based on the identified etiology.  ICD-10 code R70.8.