INTRODUCTION: Pulmonary leukostasis (PL) is a medical emergency defined by an extremely high white blood cell count (WBC) with pulmonary symptoms with or without imaging findings. This condition is seen more frequently in acute myeloid leukemia or chronic myeloid leukemia during a blast crisis and confers up to 30% mortality. Symptoms usually do not occur unless WBC exceeds 400x10 ˇ 3 / mL in patients with chronic lymphocytic leukemia (CLL). Here we present an atypical presentation of this dreaded disease.CASE PRESENTATION: An 80-year-old man with a history of atrial fibrillation, benign prostatic hyperplasia, diabetes mellitus, and a recent diagnosis of chronic lymphocytic leukemia came to the emergency room with tachypnea, hypoxia, headache, slurred speech, drowsiness, and confusion. Days before his arrival, he began with bradyphrenia, subjective fever, and dry cough. Vital signs with tachypnea and peripheral oxygen saturation of 90%. Routine laboratories stood out for 95.2 x10 ˇ 3 / mL white blood cells, with 65% immature blood cells, 17% lymphocytes, 10% neutrophils, and arterial blood gas with metabolic alkalosis and hypoxemia. Supportive therapy began with respiratory therapies every four hours, aggressive intravenous hydration, and empirical antibiotics. Chest radiography and chest computed tomography failed to show effusions, infiltrates, or consolidations. Brain studies negative for intracranial pathology. Debulking and leukoreduction therapies were discussed with the patient who decided to continue with supportive therapy, even with the risk of tumor lysis. After observation and aggressive hydration, there was a significant clinical improvement that correlated with the decrease in WBC from 95.2x10 ˇ 3 / mL to 69.9x10 ˇ 3 / mL. Noteworthy, cultures and respiratory panel were negatives. The following days the antibiotics were suspended and the patient was discharged with scheduled chemotherapy. DISCUSSION: Leukostasis is an emergency condition that, if overlooked or misdiagnosed, could be fatal if left untreated. In case of clinical suspicion, expeditious treatment is indicated since the mortality rate is approximately 20 to 40 percent regardless of the leukocytosis.CONCLUSIONS: Although it is less common in CLL and almost unthinkable with WBC less than 100x10 ˇ 3 / mL; L This case highlights the important role of high clinical suspicion of PL even if not all medical criteria are met and its response to supportive and symptomatic therapy when implemented in a rapid timely manner.
