Acute Eosinophilic Pneumonia Caused by Cigar Smoking

Introduction: Eosinophilic lung diseases (ELD) are a group of conditions that are characterized by pulmonary eosinophilia. Acute eosinophilic pneumonia (AEP) may be idiopathic in many patients, however, changes in smoking habits and drug use can trigger the disease. Case: A 24-year-old female presented to the emergency room with dyspnea for 1 week. She also had productive cough, fever of 38.7C (101.7F) and chest tightness. Although she had been vaping for the past year she switched to heavy cigar smoking 3 weeks prior to admission. Vital signs on presentation were blood pressure 127/72 mmHg, heart rate 122 beats/min, respiratory rate 28/min, oral temperature 37.4°C (99.4°F) and oxygen saturation 88% on room air. Lung exam revealed mild rhonchi. Blood work showed leukocytosis 29.13 x 103/mcL (N:4-12 x 103/mcL) with neutrophilia 26.6 x 103/mcL (N: 1.60-7.71 x 103/mcL), mild lymphopenia 1.07 x 103/mcL and a normal metabolic panel. SARS-CoV-2 PCR was negative 3 times. CT chest revealed consolidative opacities involving the right lung more than left and small bilateral pleural effusions. The patient was provided supplemental oxygen via nasal cannula and started on ceftriaxone and azithromycin for community acquired pneumonia. She rapidly declined requiring endotracheal intubation for invasive mechanical ventilation. Antibiotic coverage was broadened to vancomycin, piperacillin-tazobactam, doxycycline and levofloxacin. Further negative work up included viral pathogen panel, respiratory cultures, HIV screening, fungal antibodies, urine pneumococcal and legionella antigens, ANA and ANCA, and serum next-generation sequencing. She developed peripheral eosinophilia on hospital day 2 which peaked at 3.29 x 103/mcL (N: 0.0-0.40 x 103/mcL) on day 6. Bronchoscopy revealed no organisms on gram stain and there was no alveolar hemorrhage. Cell count from bronchoalveolar lavage (BAL) was not available. She was started on methylprednisone 60 mg every 6 hours IV for presumed AEP with marked improvement over the next 48 hours. She was discharged home shortly thereafter on an 8 week steroid taper. Discussion: AEP has been associated with new onset or resumption of cigarette smoking. Our patient had an acute onset febrile illness rapidly progressing to hypoxic respiratory failure, initial peripheral neutrophilic leukocytosis with subsequent peripheral eosinophilia, patchy bilateral ground glass and consolidative opacities with small pleural effusions, and immediate response to steroids. Prognosis is excellent if the disease is recognized and treated promptly. Conclusion: AEP is a rare cause of acute respiratory failure that can be confidently diagnosed with careful history, a constellation of symptoms and signs, and BAL eosinophilia (>20-25%).