[A case of bacteremia and suppurative vertebral osteomyelitis/discitis due to Shewanella algae occurring after raw-fish consumption].

Abstract

Shewanella algae is an aquatic gram-negative bacterium, rarely recovered from human clinical samples. Case reports of human Shewanella infection are, however, slowly increasing, and a Shewanella infection outbreak was reported at a South Korean hospital. We report the case of an 89-year-old man admitted for back pain and fever after eating raw marine fish. Sulbactam/cefoperazone was started under a tentative diagnosis of gall bladder inflammation with gallstones based on ultrasonographic findings. His persistent back pain, however, necessitated vertebral magnetic resonance imaging (MRI), which showed thoracic vertebral osteomyelitis and discitis. Two sets of blood culture on admission yielded a gram-negative bacillus identified as "Shewanella putrefaciens" by automated identification. Ceftriaxone administration for 3 weeks followed by oral levofloxcin for 5 weeks cured the vertebral osteomyelitis and discitis. 16S rRNA sequence analysis showed that "S. putrefacien" was, in fact, S. algae-incorrectly detected because semi-automated and automated identification did not include S. algae in their database. It should thus be kept in mind that consuming raw-fish may cause Shewanella bacteremia and osteomyelitis in patients with hepatobiliary disease and that genetic analysis is required to precisely determine the occurrence of Shewanella spp.