Evaluation of a Treatment Algorithm for Tsushima Mamushi (Gloydius tsushimaensis) Snakebites, after Its Introduction to Tsushima Island, Nagasaki, Japan

OBJECTIVE: Tsushima mamushi (Gloydius tsushimaensis) is an endemic species of snake inhabiting only Tsushima Island, a remote Japanese island. We conducted a multicenter, retrospective study of G. tsushimaensis bites for the first time and developed a treatment algorithm that unified treatment on the island and is still in use today. METHODS: This is a multicenter, retrospective study comparing 72 cases from January 2005 to December 2018, before the introduction of the algorithm, and 12 cases from January 2019 to December 2020, after its introduction. RESULTS: There was no significant decrease in the maximum grade of symptoms after the introduction of the algorithm, but there was a decreasing trend (p=0.057). Conversely, the median of the maximum creatinine kinase levels was 343.5 IU/L (interquartile range: 115.5-4,745.5) before the algorithm's introduction and significantly lower (142.5; interquartile range: 111.3-163) after the algorithm's introduction (p=0.042). After the algorithm's introduction, the disseminated intravascular coagulation merger rate and the acute kidney injury incidence both dropped to 0%, from 9.7% and 6.9%, respectively, before the algorithm's introduction. There was no significant difference in the length of hospital stay before versus after the algorithm's introduction. CONCLUSION: This study showed that the treatment algorithm can be safely and quickly applied. The algorithm's effectiveness is expected to be strengthened by the accumulation of more cases in the future.