The First Case Report of Community-Acquired Infective Endocarditis Due to Sequence Type 1223 Staphylococcus argenteus Complicated with Convexity Subarachnoid Hemorrhage

Abstract

Staphylococcus argenteus is a new species classified as part of the Staphylococcus aureus-related complex in 2015 and has been recognized to be as pathogenic as S. aureus. We describe the first case of endocarditis caused by S. argenteus. A 51-year-old man presented with chief complaints of fever and headaches. On admission, he showed a slight decrease in consciousness level (Glasgow Coma Scale, E4V4M6). Careful physical examination and imaging revealed a systolic heart murmur, Janeway lesions, and complicating convexity subarachnoid hemorrhage (cSAH) of the left frontal lobe. Ceftriaxone 4 g/day was administered immediately after blood cultures were obtained. The next day, all blood cultures grew Gram-positive cocci, identified as Staphylococcus aureus or Staphylococcus argenteus by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). However, the version of MALDI-TOF MS used could not distinguish these bacteria. Although we could not find valvular vegetation, he was clinically diagnosed with infective endocarditis according to the modified Duke's criteria. Meropenem 6 g/day and linezolid 1.2 g/day were started to cover S. aureus and methicillin-resistant S. aureus. Finally, ampicillin was selected based on drug susceptibility, and the patient was treated for 8 weeks and recovered without permanent damage. The isolated strain formed white colonies on blood agar plates, characteristic of S. argenteus, and differs from golden colony-forming S. aureus. Genetic analysis revealed the isolated strain as S. argenteus (sequence type 1223). Although distinguishing S. argenteus from S. aureus using routine conventional laboratory tests is difficult, the updated library version of MALDI-TOF MS is useful in identifying S. argenteus. Interestingly, all published cases of infection caused by ST1223 have been reported in Japan. Therefore, the trend of infections from the ST1223 strain should be carefully monitored, particularly in Japan. Further investigation is needed to clarify the epidemiology and clinical characteristics of S. argenteus infection, as there are few studies regarding this pathogen.

Fatal bacteremia caused by Staphylococcus argenteus: A case report

“…[1,2] It causes infections similar to those triggered by S aureus, including skin and soft tissue infections, respiratory infections, necrotizing fasciitis, bone and joint infection, endocarditis, aortic mycotic aneurysm, bacteremia and sepsis, and food poisoning. [13][14][15][16] After the first report of genetically divergent ST75 in Australia in 2002, S argenteus were increasingly reported globally, including Cambodia, Trinidad and Tobago, New Zealand, Fiji, France, Thailand, China, Belgium, Laos, Japan, Denmark, Myanmar, Sweden, Taiwan, German, Nigeria, Canada and the United States, England, and Brazil. [13,17,18] Chen et al reported that compared with patients with methicillin-susceptible S aureus (MSSA) bacteremia, patients with S argenteus bacteremia had a higher percentage of polymicrobial blood culture results (P = .047), prior healthcare-associated exposure within the past year (P = .026), recent hospitalization within 3 months (P = .027), thrombocytopenia (P = .027), and the respiratory tract as the primary focus of infection (P = .028).…”

“…So far, the most feasible approach employed in clinic is based on the application of MALDI-TOF MS which can identify several specific signals that contribute to the resistance rate of S argenteus differentiation of bacterial species. [5,15,16,19,20] Routine biochemical methods such as agglutination cannot distinguish S argenteus from S aureus . [15] Up to date, there are no commercially available DNA-based assays for the identification of S argenteus .…”

“…[21] In this case, the isolate is penicillin-resistant and sensitive to methicillin and other tested antibiotics, which is consistent with other reports. [16,20,21] With the reports of methicillin-resistant S argenteus isolates were identified, [3] the emergence of methicillin resistance in S argenteus shows the potential for obtainment of the methicillin resistance gene in its biological evolution. As the invasion and dissemination of S argenteus into healthcare facility environments with high antibiotic pressure, the threat of the emergence of methicillin resistance in S argenteus is possible and deserves further concern for public health benefits.…”

Antimicrobial and biocide resistance in Staphylococcus aureus: genomic features, decontamination strategies, and the role of S. aureus complex-related species, with a focus on ready-to-eat food and food-contact surfaces

“…Therefore, bushmeat could actually be a possible source of contamination and spreading of such novel species, deserving investigation in the near future. Conversely, S. argenteus, known for its ability to cause various pathological conditions in humans (e.g., sepsis, joint infection, endocarditis, and lymphadenitis) (Chantratita et al, 2016;Jiang et al, 2018;Ohnishi et al, 2018;Hirai et al, 2022) and animals (e.g., abscess, wound infection, and bovine mastitis) (Indrawattana et al, 2019;Pumipuntu et al, 2019;Meijer et al, 2022), is being reported from food, and it is increasingly recognized as an emerging foodborne pathogen (Shi and Zhang, 2018;Fusco et al, 2020), being able to cause staphylococcal food poisoning due to the production of enterotoxins, as assessed in three outbreaks reported so far in Japan (Suzuki et al, 2017; Frontiers in Food Science and Technology frontiersin.org ). Although the actual prevalence and distribution of S. argenteus in food products and food-related environments is still unclear (Shi and Zhang, 2018), S. argenteus has been recently reported from different food sources, including RTE food, comprising those involved in food poisoning, as well as contact surfaces of kitchen utensils and specimens from food handlers (Table 3).…”

Prevalence and Characteristics of Invasive Staphylococcus argenteus among Patients with Bacteremia in Hong Kong

“…S. argenteus can cause infections in bone and joints, infective endocarditis, mycotic aneurysm, as well as bloodstream infections [6,7,[19][20][21][22][23][24][25]. Cases of food poisoning caused by S. argenteus enterotoxins have also been reported in Japan [26,27].…”