Essay Example on Acute eosinophilic pneumonia AEP is Rare

Introduction Acute eosinophilic pneumonia AEP is rare It often results in acute Respiratory failure with an attended mortality Acute eosinophilic pneumonia is characterized by infiltration of pulmonary parenchyma with eosinophilic infiltrates and often associated with peripheral eosinophilia 1 2 It has been associated with antibiotics certain chemicals and Non steroidal anti inflammatory agents 3 The pathophysiology of AEP involves detection of the offending agent by alveolar macrophages which presents the antigen to T helper cells which in turn produce interleukin 5 that along with eotaxin produced by endothelial cells epithelial cells macrophages and airway smooth muscle cells result in accumulation of eosinophils in the alveolar spaces This in turn results in acute epithelial injury5 We present a patient with AEP following therapy with Daptomycin Case Report 

A 65 year old Caucasian male with past medical history of chronic kidney disease stage 3 liver cirrhosis thoraco lumbar spinal stenosis status post surgery presented to the hospital because of progressive dyspnea fever non productive cough malaise for two days The patient had a recent spinal stenosis surgery complicated by T5 8 vertebral osteomyelitis with epidural phlegmon requiring drainage and debridement and removal of some hardware After the debridement the patient was also started on empiric antibiotics with vancomycin and cefepime Vancomycin and cefepime were replaced with Daptomycin when cultures from the phlegmon grew Methicillin sensitive Staphylococcus Aureus MSSA The patient received Daptomycin for three weeks On arrival at the hospital patient had stable vital signs except a low SPO2 of 90 He looked slight distressed with his breathing His Respiratory rate was slight tachypneic and Lung examination revealed scattered bi basal crackles Laboratory studies revealed a moderate Polymorphonuclear leukocytosis and eosinophilia 16 Table I His chest X ray and CT chest are shown in figure 

I Due to recent exposure to daptomycin a diagnosis of AEP secondary to daptomycin was strongly suspected requiring pulmonary consultation Bronchoscopy and Broncho Alveolar Lavage BAL revealed an eosinophil count of 20 Do we have actual percentage Special staining for Pneumocystis fungi and AFB were negative Bacterial fungal and cultures for Mycobacterium Tuberculosis were negative Aerobic and Anaerobic Blood cultures were negative as well Table II Daptomycin was discontinued and the patient was started on intravenous solumedrol and a combination of Vancomycin and Cefepime Patient responded to this regimen in the next 24 48 hours with subjective improvement and did not require supplemental oxygen Patient was discharged home on reducing course of steroids and a repeat CT chest revealed a good resolution of the bilateral peripherally distributed infiltrates Acute eosinophilic pneumonia in relation to daptomycin has been characterized into definite probable possible and unlikely 1 To date 35 cases of daptomycin induced AEP have been described in the literature The product labeling has been recently updated to include AEP and pulmonary eosinophilia among the side effects In 2007 pulmonary eosinophilia was added as an adverse reaction after post marketing survey The precise mechanism for lung injury secondary to Daptomycin is not known It is believed that Daptomycin binds to pulmonary surfactant which in turn causes epithelial injury Daptomycin induced AEP is common in elderly male receiving dose doses in the range of 4 10mg kg day Renal failure is associated with increased risk of developing AEP in response to daptomycin 

Peripheral eosinophilia is present in majority of cases 3 A diagnoses of AEP doesn t require a lung biopsy and can be diagnosed based on suggested criteria however a lung biopsy is helpful when diagnosis is uncertain or in patients who don't respond to conventional therapy 4 6 AEP is characterized by presence of fever dyspnea nonproductive cough with diffuse pulmonary infiltrates frequently leading to hypoxemic respiratory insufficiency 5 At present diagnosis of Eosinophilic pneumonia is attributed to daptomycin if the following criteria are met 1 concurrent exposure to daptomycin 2 fever 3 dyspnea with hypoxemic respiratory failure 4 new infiltrates on chest radiography 5 Bronchoalveolar lavage BAL with 25 eosinophils and 6 clinical improvement following daptomycin withdrawal Absence of eosinophils 25 in BAL may represent interplay between host and immunogen and altered immune response in affected individuals People who have lowered immune defense mechanism may not mount cellular response to offending agents It is also possible to diagnose the AEP at early stage when significant immune response has not been mounted and resulting insignificant eosinophilic response We believe the current criteria for diagnosis should be tailored to patient population This case enlightens importance of timely recognition and treatment of daptomycin induced eosinophilic pneumonia It is still not clear as to how long should the treatment with steroids be continued There is always a significant concern regarding exacerbation of underlying infections especially those involving bones when patients are being treated with steroids In our patient prednisone was given only for 2 weeks and patient has not had any relapse of his pulmonary symptoms A shorter course of steroid with rapid taper should be sufficient to treat majority of cases We believe that in the right setting lung biopsy is not essential for the diagnosis Healthcare providers should be aware of daptomycin related EP and timely discontinuation of Daptomycin could potentially prevent acute respiratory failure and the attended mortality