Outcomes of Mycotic Abdominal Aortic Aneurysms in the Native Aorta: A Single Referral Center Study

Mycotic abdominal aortic aneurysms (MAAAs) are rare but often lethal with little data to guide management decisions. Given the paucity of on MAAAs, this study’s objective was describe a single tertiary center experience MAAAs focus presenting symptoms, causative organisms, and postoperative outcomes. This single-center retrospective study from June 2012 February 2020 all confirmed or strongly suspected native aorta. The primary inclusion criterion infection aorta below diaphragm. obtained institutional review board approval, patient history, operative characteristics, organisms involved, complications, mortality were retrieved via manual encounters notes. Statistical analyses performed using χ2 tests, Cox proportional hazard ratios, linear mixed-effects model analysis. Overall, 27 cases included, 26 (96%) which underwent repair cryopreserved homograft in situ 1 synthetic polytetrafluoroethylene graft extra-anatomic repair. Patients MAAA had an average age 68 (±11) years Charlson comorbidity scores 5 (±3.8), identifiable 23 (85%) (Table I). most common symptom pain, occurred 89% fever, elevated WBC, nausea Peripheral blood cultures identified organism 14 (52%). responsible MSSA (n = 5), total 16 distinct species (11 gram-positive, gram-negative, 2 fungi) III). Postoperatively, complication pulmonary effusion, edema, pneumonia (37%) IV). All-cause 30-day 90-day 15% 23%, respectively, survival at 3 77% 56%, respectively (Fig). Kaplan-Meier over impacted by presence penetrating ulcer odds ratio 2.1 for earlier (P .024). investigation demonstrates that is still associated high 90 days after cohort indicates erosion may be worse wide variety can opportunistically infect AAAs. Homograft remains preferred approach in-line MAA series. Future directions work will increase numbers better observe whether symptom-specific markers predict outcomes optimal MAAAs.Table IPatient characteristics presentationCharacteristicNo. (%)90-day (%)P valuebTotal population27 (100)6 (23)a–Comorbidities Smoking statusNever5 (19)1 (20)–Prior11 (48)1 (9).475Current11 (33)4 (40).55 Coronary artery disease6 (22)1 (14).678 Prior CABG/PCI6 (22)2 (33).998 Previous vascular intervention2 (8)0 (0).997 Cerebrovascular disease2 (7)1 (50).997 Hypertension21 (78)4 (20).636 Congestive heart failure4 (15)0 (0).996 COPD1 (4)0 (0).998 Diabetes8 (30)1 (12).65 ESRD dialysis6 (33).47Preoperative medications Statin13 (48)3 (23).677 β-Blocker10 (37)2 (20).69 ACE-inhibitor8 (30)2 (25).577 Aspirin17 (63)3 (18).611 Antibiotic5 (20).947 Other anticoagulant2 (7)0 (0).998Clinical presentation Blood positive14 (52)2 (14).364 Aortic tissue examined infection26 (96)6 (24)1 positive17 (63)4 (25).287 Infectious identified25 (92)6 (25).997 Gastrointestinal fistula1 (4)1 (100).998 Spine involvement5 (19)0 Contained rupture12 (44)3 (27).782 Pseudoaneurysm17 (63)5 (29).248 Penetrating ulcer15 (56)5 (36).0726 Leukocytosis (>10.0 g/L)17 (63)6 (38).997 SymptomsFever chills11 (41)0 (0).997Pain24 (89)6 (26).997Nausea6 (20).996ACE, Angiotensin-converting enzyme; CABG, coronary bypass graft; COPD, chronic obstructive disease; ESRD, end-stage renal PCI; percutaneous intervention.aOne excluded due no mortality.bCalculated base including disease, hypertension, congestive failure, diabetes, ESRD. Open table new tab Table IIOperative characteristicsOperative characteristicsNo. valueGraft type Homograft26 (96)5 (20).998 Synthetic1 (100).998Location Upper third6 (33).908 Middle third25 (92)5 Lower third15 (56)1 (7).0669 Clamp placement above arteries12 (27).384 IIIInfectious identifiedOrganism identifiedNo. valueMSSA5 (19)2 (40).994Streptococcus pneumoniae3 (11)1 (33).998Salmonella group D2 (0).998Thysanophora penicillioides1 (0)1Enterococcus faecalis1 (100)1Capnocytophaga canimorsus1 (0)1Peptostreptococcus1 (0)1Enterobacter cloacae1 (0)1Streptococcus mitis1 (100)1Staphylococcus epidermidis1 (0)1Epicoccum nigrum1 (0)1Mycobacterium bovis1 (0)1Bacteroides fragilis1 (100)1Klebsiella pneumoniae1 (0)1Viridans streptococcus1 pyogenes1 (0)1Listeria monocytogenes1 (0)1Clostridium perfringens1 (0)1Unidentified2 (0).996MSSA, Methicillin-resistant Staphylococcus aureus. IVOutcomes repairComplicationNo. (%)Postoperative MI1 (4)Postoperative CHF0 (0)Postoperative complication10 (37)Postoperative AKI9 (34)Postoperative delirium7 (26)Postoperative stroke1 (4)6 week antibiotics16 (86)Return operating room7 (26)Surgical site infection1 (4)30-day mortality4 (15)90-day mortality6 (23)1-year (22)3-year mortality10 (37)AKI, Acute kidney injury; CHF, congenital failure; MI, myocardial infarction.