Wound Infections from Taiwan Cobra (Naja atra) Bites: Determining Bacteriology, Antibiotic Susceptibility, and the Use of Antibiotics-A Cobra BITE Study.

Wound necrosis and secondary infection are common complications after Naja atra bites. Clinical tools to evaluate the infection risk after Taiwan cobra bites are lacking. In this Cobra BITE study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with Taiwan cobra snakebites. Patients with wound infection lacking tissue necrosis were included in developing Cobra BITE score utilizing univariate and multiple logistic regression, as patients with wound necrosis require antibiotics for infection treatment. 8,295,497 emergency department visits occurred in the span of this study, with 195 of those patients being diagnosed as having cobra bites. Of these patients, 23 had wound necrosis, and 30 had wound infection, resulting in a wound infection rate of 27.2% (53/195). Enterococcus faecalis and Morganella morganii were the main bacteria identified in the culture report regardless of whether patients' wounds had necrosis. As per our Cobra BITE score, the three factors predicting secondary wound infection after cobra bites are hospital admission, a white blood cell count (in 103/µL) × by neu-trophil-lymphocyte ratio value of ≥114.23, and the use of antivenin medication. The area under the receiver operating characteristic curve for the Cobra BITE score system was 0.88; ideal sensitivity and specificity were 0.89 and 0.76. This scoring system enables the assessment of wound infections after N. atra bites, and it could be modified and improved in the future for other Naja spp. bites.

High-resolution bacterial growth inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of antibacterial constituents in Chinese plants used to treat snakebites.

ETHNOPHARMACOGICAL RELEVANCE: Bacterial infection is one of the main secondary infections caused by snakebite. The 88 plant species investigated in this study have been used as folk remedies for treatment of snakebite, and it is therefore the aim of this study to investigate whether the plants contain compounds with bacterial growth inhibition. MATERIALS AND METHODS: The water and ethanol extracts of 88 plant species were screened at 200 µg/mL against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa for their antibacterial activity by micro-broth dilution assay. The most active extracts were fractionated into microplates using analytical-scale RP-HPLC, and subsequently growth inhibition was assessed for each well. The biochromatograms constructed from these assays were used to identify compounds responsible for antibacterial activity. The structures of five compounds were elucidated by HPLC-HRMS-SPE-NMR. RESULTS: Crude extracts of Boehmeria nivea, Colocasia esculenta, Fagopyrum cymosum, Glochidion puberum, Melastoma dodecandrum, Polygonum bistorta, Polygonum cuspidatum and Sanguisorba officinalis showed MIC values below 200 µg/mL against either Bacillus subtilis, Staphylococcus aureus, Escherichia coli or Pseudomonas aeruginosa. The biochromatograms demonstrated that tannins play a main role for the bacterial growth inhibition observed for all above-mentioned plants except for Polygonum cuspidatum. Furthermore, the high-resolution bacterial growth inhibition profiling combined with HPLC-HRMS-SPE-NMR allowed fast identification of three non-tannin active compounds, i.e., piceid, resveratrol and emodin from ethanol extract of Polygonum cuspidatum. CONCLUSION: The high-resolution bacterial growth inhibition profiling allowed fast pinpointing of constituents responsible for the bioactivity, e.g., either showing tannins being the main bacterial growth inhibitors as observed for the majority of the active plants, or combined with HPLC-HRMS-SPE-NMR for fast structural identification of non-tannin constituents correlated with antibacterial activity.