Development and internal validation of a Wasp Sting Severity Score to assess severity and indicate blood purification in persons with Asian wasp stings

Abstract

Background In recent years, the incidence of wasp sting has increased annually in China. Organ damage and high mortality due to mass wasp envenomation remain major challenges. Timely and appropriate medical intervention can improve survival. However, there are currently no normalized tools for early assessment of severity. Methods The clinical data of wasp sting patients hospitalized from 2011 to 2019 were used as a training set. Logistic regression was used to explore major risk factors for the development of a severe case of wasp stings (SC). The Wasp Sting Severity Score (WSS) was determined considering these risk factors to identify SCs and was tested in a validation dataset that was prospectively collected in 2020. Results The data of 1131 wasp sting patients from 2011–2019 were included in the training set. Logistic regression analysis showed that tea-colored urine (TCU), number of stings, and lactate dehydrogenase (LDH) and total bilirubin (TBIL) levels were risk factors for developing a SC. The WSS was developed considering these four risk factors, and the total possible WSS was 20 points. The WSS was tested using the validation dataset, comprising the data of 153 patients, in 2020, and we found that a WSS ≥3 points was an important indication for blood purification, with a sensitivity of 71.9%, specificity of 92.6% and an area under the curve (AUC) of 0.918 (95% CI 0.873–0.962). Among patients with more than 30 stings, mortality in those who underwent plasma exchange (PE) within 24 hours after admission was significantly lower than that in those who did not receive PE treatment (14.3% vs. 46.9%, P = 0.003). However, continuous venovenous hemofiltration (CVVH) (P = 0.317) and hemoperfusion (HP) (P = 0.869) did not significantly reduce mortality. Conclusions Patients with WSS scores ≥ 3 should be considered for blood purification as early as possible in addition to routine treatment. In addition, PE is better than CVVH and HP at reducing mortality in patients suffering from severe wasp stings.

Wasp stings and plasma exchange

“…This conceptual figure summarizes data presented in Fig. 1D from [ 7 ]. Fewer than 20 stings were not associated with mortality, but mortality increased with a higher number of stings and peaked with 50 or more stings.…”

“…The location of Suining Central Hospital (Sichuan Province) and the species reported by Liu et al. to be associated with hospitalization are also indicated [ 7 ].…”

“…In a recent issue of ckj , Liu et al . describe their experience at Suining Central Hospital (Sichuan Province, southwest China) where they treat 100–200 wasp sting patients per year and now report the experience with 1284 patients from 2011 to 2020 [ 7 ]. Consistent with other reports from China, most cases were due to V. basalis stings (Fig.…”

“…Native American and European species are considerably less toxic than Asian species. As examples referenced by Liu et al ., the USA reports of a lethal dose of 20 stings/kg [ 8 , 9 ] do not apply to Asian wasps that may kill with as few as >20 stings per person [ 7 ]. As Asian wasps invade America and Europe, the report by Liu et al .…”

Correlation between early changes of serum lipids and clinical severity in patients with wasp stings

“…3 In China, wasp stings have occurred more frequently in recent years, and the mortality of wasp stings can reach 6% or more. 4 Wasp venom, a mixture of various components, mainly includes histamine phospholipase A2 (PLA2), melittin, hyaluronidase, mastoparans and serotonin. 4 From a clinical perspective, patients with wasp stings may have several clinical manifestations.…”