211. Coxiella burnetii: 7 Years of Experience at a Tertiary-Care Center.

Background Q fever is a zoonotic disease caused by Coxiella burnetii. Primary infection can progress to persistent infection irrespective of initial symptomatology. Our aim is to describe the clinical features, treatment, risk of progression, use of prophylaxis, and outcomes of Coxiella burnetii infection at our institution. Methods We did a retrospective review of all adult patients with positive Coxiella burnetii serology at Mayo Clinic, Rochester from 1st January 2012 to 31st December 2018. Centers for Disease Control and Prevention (CDC) case definition and classification were used to group the patients into confirmed and probable acute Q fever, and confirmed and probable chronic/persistent Q fever. Data on demographics, clinical presentation, comorbid conditions, exposure history, risk factors associated with progression, serology, treatment and outcomes were collected. Results We found 266 patients with positive titres of Coxiella IgG or IgM greater than 1:16, of which 49 patients met the CDC case definition for Q fever. Median age at presentation was 62 years. 45/49 (91. 8%) were men, while 4/49 (8%) were women. 20/49 (40. 8%) patients presented with acute Q fever of which 5 (25%) patients progressed to persistent infection. 29/49 (59%) patients presented with persistent Q fever of which 4 patients could recall symptoms suggestive of acute Q fever. The most common presentation of acute Q fever was acute febrile illness (65%). Endocarditis (11/29) was the most common presentation of chronic/persistent Q fever. Of the 5 patients with acute Q fever that progressed to persistent infection, 3/5(60%) progressed despite being on doxycycline and hydroxychloroquine. 8/29 patients with persistent Q fever had serological resolution at last follow-up. 2/4(50%) deaths were attributable to Q fever. Conclusion Minority of the patients tested met the case definition. 25% of patients with acute disease progressed to chronic Q fever out of which 60%(3/5) progressed despite prophylaxis. Endocarditis and vascular infections were the most common chronic cases. Interestingly we found 4 cases of MPGN in association with Q fever. Prosthetic valves are the most important risk factors for progression (P = 0.02). Serological cure often lags behind clinical cure (27% vs. 68% in persistent infection)(Table 4). Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]