Expedient management of Listeria monocytogenes endovascular graft infection in an immunosuppressed patient

Introduction

Listeria monocytogenes is a rare cause of infection following endovascular aneurysm repair (EVAR); there remains lack of consensus on the optimal management strategy, in particular the need for life-long suppression. Despite this organism’s increased pathogenicity amongst immunosuppressed hosts, to date no EVAR infections have been described in this cohort.

Here we describe the first case ofListeria monocytogenesEVAR infection in an immunocompromised host.

Case description

A 75-year-old gentleman presented with a 5-day history of back pain, fever and dysuria despite 3 days of oral co-amoxiclav for presumed urinary tract infection. There was no recent gastrointestinal upset. Admission blood and urine cultures were negative.

Past medical history included on-going methotrexate therapy for rheumatoid arthritis and EVAR of the infra-renal aorta in 2013.

A CT abdomen, performed to exclude intra-abdominal pathology, revealed an enlarged aneurysmal sac and fat stranding, secondary to inflammation. A CT-guided sample of aneurysmal fluid was obtained before commencing empirical piperacillin-tazobactam and vancomycin; Listeria monocytogeneswas isolated from subculture after 5 days broth enrichment. The EVAR was removed and replaced 7 days after admission and antimicrobials rationalised to intravenous amoxicillin, ciprofloxacin and metronidazole.

The patient completed 6 weeks intravenous therapy, then commenced lifelong suppressive therapy with oral co-trimoxazole 960mg OD.

Discussion

Listeria monocytogenesEVAR infection has been described in only 8 patients; this is the first in an immunosuppressed patient. This case adds to the literature by outlining a putative management strategy, involving explanation and life-long antimicrobials, for immunocompromised patients with Listeria monocytogenes EVAR infection.