Fatal case of ST8/SCCmecIVl community-associated methicillin-resistant Staphylococcus aureus infection in Japan

Abstract

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) with ST8/SCCmecIV threatens human health. However, its pathogenesis remains unclear. ST8 CA-MRSA (CA-MRSA/J) with SCCmecIVl, which carries the large LPXTG-motif–containing putative adhesin gene, spj, has emerged in Japan. We present the first reported case of death from CA-MRSA/J. The patient was a 64-year-old woman with iliopsoas abscesses complicated by septic pulmonary embolism and multiorgan abscesses. Vancomycin, arbekacin, daptomycin and rifampicin were ineffective. CA-MRSA/J was resistant to erythromycin, clindamycin and antiseptics and was invasive in a HEp-2 cell assay, in contrast to skin-derived villous-adherent CA-MRSA/J. This suggests the strongly invasive pathotype of CA-MRSA/J.

Structures of a highly variable cell‐wall anchored protein‐encoding the spj gene from ST8/SCCmecIVl community‐associated methicillin‐resistant Staphylococcus aureus (CA‐MRSA/J) isolated from 2003 onwards: An indicator of a strongly invasive pathotype

“…We previously reported on ST8/SCC mec IVl CA‐MRSA (CA‐MRSA/J) in 2012 . CA‐MRSA/J is associated with a broad range of disease manifestations, one death having been caused by a strongly invasive pathotype, and can be transmitted on public transport, including having been spread internationally to Hong Kong . A key feature of SCC mec IVl is a large CWA protein encoding the spj gene .…”

“…A key feature of SCC mec IVl is a large CWA protein encoding the spj gene . Although we analyzed the genome of the invasive NN50 strain, isolated in 2008, initial strains (NN3 and NN4) isolated from bullous impetigo in 2003 and SI1 strain from the first fatal case in 2012 await investigation. In the present study, we analyzed the SCC mec IVl structures of these four strains, together with 26 other CA‐MRSA/J strains, our aim being to identify a factor/structure specific to the strongly invasive SI1 pathotype.…”

“…Genes analyzed included staphylococcal superantigen genes on S. aureus pathogenicity island and immune evasion cluster genes on phage Sa3 . Susceptibility testing was performed according to previously described procedures . The 30 antimicrobial and related agents tested (Table S4) included three β‐lactams, seven aminoglycosides, two macrolides/lincosamides, two glycopeptides, linezolid, daptomycin, levofloxacin, rifampicin, trimethoprim, sulfamethoxazole, tetracycline, fosfomycin, mupirocin, fusidic acid; and six antiseptics (including benzalkonium chloride) and related agents (ethidium bromide).…”

“…The 30 antimicrobial and related agents tested (Table S4) included three β‐lactams, seven aminoglycosides, two macrolides/lincosamides, two glycopeptides, linezolid, daptomycin, levofloxacin, rifampicin, trimethoprim, sulfamethoxazole, tetracycline, fosfomycin, mupirocin, fusidic acid; and six antiseptics (including benzalkonium chloride) and related agents (ethidium bromide). Plasmids were transferred as described previously …”

“…Antibodies against the Spj 11/22‐aa repeats (NN50), STEESTKEEQPSAEEVGKEAQS (N → C), were made in rabbits; the antibody‐bound cells having been detected by FITC‐labeled second antibody. A HEp‐2 cell infection assay was performed using SEM and TEM, as described previously . Data were analyzed statistically with Fisher's exact test.…”