An approximately 80-year-old male with unknown medical history is brought to the emergency department from a skilled nursing facility after unwitnessed arrest – EMS providers established return of spontaneous circulation after chest compressions and epinephrine. On arrival, the patient was hypotensive (MAP 40mmHg) and hypoxic (SpO2 85%) with mask ventilation. The patient was intubated, resuscitated with intravenous fluids and started on vasopressors. Imaging demonstrated lung consolidation consistent with multifocal pneumonia versus aspiration. Laboratory studies were obtained:
- CBC: WBC: 49.2 (N: 64%, Bands: 20%)
- ABG: pH: 7.07, pCO2: 73mmHg
- Lactate: 9.1mmol/L
The patient was admitted to the medical intensive care unit for cardiopulmonary arrest presumed secondary to hypoxia and septic shock from healthcare-associated pneumonia or aspiration. The markedly elevated white blood cell count was attributed to a combination of infection and tissue ischemia from transient global hypoperfusion.
- Markedly elevated leukocyte (particularly neutrophil) count without hematologic malignancy
- Cutoff is variable, 25-50k
Review of Available Literature
- Retrospective review of 135 patients with WBC >25k 2
- 48% infection
- 15% malignancy
- 9% hemorrhage
- 12% glucocorticoid or granulocyte colony stimulating therapy
- Retrospective review of 173 patients with WBC >30k 3
- 48% infection (7% C. difficile)
- 28% tissue ischemia
- 7% obstetric process (vaginal or cesarean delivery)
- 5% malignancy
- Observational study of 54 patients with WBC >25k 4
- Consecutive patients presenting to the emergency department
- Compared to age-matched controls with moderate leukocytosis (12-24k)
- Patients with leukemoid reaction were more likely to have an infection, be hospitalized and die.
Differential Diagnosis of Leukemoid Reaction 1,5-8
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