Case Presentation: A 56-year-old male with history of spinal epidural abscess being treated with IV daptomycin, presented to the emergency department with a fever of 104° F. The patient had a history of recurrent epidural abscesses, requiring multiple surgical washouts, following past lumbar diskectomy subsequent to lumbar radiculopathy. Previous cultures were positive for two strains of Staphylococcus epidermidis, and the patient was started on a 6-week course of IV daptomycin approximately 2 weeks prior to current presentation.The patient was admitted and began empiric vancomycin and cefepime as symptoms were thought to be due to continued infection at his surgical site. Initial MRI demonstrated persistent ventral epidural fluid collection that was decreased in size from previous MRI. Due to continued fever on hospital day 2, a chest x-ray was ordered which demonstrated patchy interstitial pneumonic infiltrates bilaterally, and the patient was started on empiric treatment with azithromycin. Over his hospital course, the patient developed worsening shortness of breath that was not present at admission. Subsequent consult via pulmonology noted that the patient’s CXR, in conjunction with eosinophilia noted on CBC, could indicate eosinophilic pneumonia, likely secondary to recent daptomycin use. Bronchoscopy with bronchoalveolar lavage was conducted on hospital day 6 and demonstrated eosinophilia of pulmonary secretions, and the patient was subsequently placed on IV steroids for treatment of acute eosinophilic pneumonia. The patient was discharged on hospital day 9 with IV vancomycin, oral levofloxacin, an oral steroid taper, and oral sulfamethoxazole-trimethoprim for pneumocystis pneumonia prophylaxis. CXR 7 weeks after discharge demonstrated significant resolution of the interstitial lung opacities. At present, the patient has no residual pulmonary symptoms.
Discussion: Daptomycin is a cyclic lipopeptide antibiotic with great efficacy targeting gram-positive cocci, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus. Acute eosinophilic pneumonia (AEP) is a rare complication of daptomycin use, with a poorly understood etiology thought to involve accumulation of the drug in pulmonary surfactant inducing inflammation. Diagnosis of AEP requires a high degree of clinical suspicion, as identification may be further complicated by the fact that symptoms can present anywhere from days to weeks after beginning therapy. Diagnostic criteria include fever, exposure to daptomycin, dyspnea with requirement for oxygen therapy, bilateral infiltrates on CXR, bronchoalveolar lavage with >25% eosinophils, and clinical improvement following discontinuation of daptomycin. This complication is very responsive to treatment with corticosteroids and cessation of daptomycin, but recognition is essential.
Conclusions: Daptomycin is a relatively new antibiotic, with increasing use subsequent to continued emergence of antibiotic resistance and convenience for outpatient intravenous antibiotic therapy compared to vancomycin. With increased frequency of use, it is essential that physicians are aware of this rare complication of daptomycin therapy.