Correlation of pseudohypoxemia and leukocytosis in chronic lymphocytic leukemia.

Pseudohypoxemia has been reported in leukemic patients with extreme leukocytosis, and it is characterized by a low oxygen saturation on arterial blood gas analysis despite normal saturation on pulse oximetry. We report the case of a 51-year-old man with chronic lymphocytic leukemia and an elevated white blood cell (WBC) count after splenectomy, his progressive postoperative pseudohypoxemia gradually improved as the leukocytosis was lowered by chemotherapy. We believe this is the first report to show a statistically significant correlation between the WBC count and the degree of pseudohypoxemia in a patient with leukemia.