Soft tissue calcifications secondary to Hymenoptera stings: a potential prognostic CT imaging sign in pediatric patients.

Context: Soft tissue calcifications (STCs) were incidentally found in some of the Hymenoptera-stung (HS) children when they underwent computed tomography (CT) scans for evaluating complications of vital organs. Afterwards, a predilection of STCs to the children with severe complications was clinically noticed. A hypothesis was then developed that STCs secondary to HS may correlate with poor outcomes.

Objective: This study aims to firstly characterize the CT findings of STCs in HS children and to confirm our hypothesis that the occurrence of STCs may act as an indicator of poor outcomes in HS children.

Materials And Methods: Children who received CT scanning after Hymenoptera sting from January 2011 to October 2016 in our hospital were analyzed retrospectively. Shape, location, and distribution of the STCs were described according to the CT findings. Then the enrolled cases were classified into Soft Tissue Calcification Group (STCG) and non-Soft tissue Calcification Group (non-STCG) to conduct prognostic comparisons of Sequential Organ Failure Assessment (SOFA) scores, incidence of main complications (acute liver failure (ALF), acute kidney injury stage III (AKI-III) and multiple organ failure (MOF)), length of hospital days, and in-hospital death, respectively. Pearson correlation was also utilized between the cumulative volume of STCs and the SOFA score.

Results: Sixteen cases were enrolled, and STCs' incidence was 56.25% (9/16). Two STCG cases had diffuse nodular calcifications in their swollen subcutaneous tissue, and another seven had symmetrically stripy or patchy calcifications within or along local muscles. The SOFA scores during the first 3 days were all higher in STCG, and rose to the greatest difference at the third day (9.78 ± 2.17 vs. 2.29 ± 2.06, t = 7.009, p < .001); the incidence of ALF, AKI-III and MOF were significantly higher in STCG (66.67% vs. 0, p = .011), (77.78% vs. 0, p = .003) and (77.78% vs. 14.29%, p = .041); and children in STCG were treated with longer hospital durations (26.33 ± 8.41 days vs. 12.29 ± 7.36 days, t = 3.493, p = .004). One child in STCG died of cardiopulmonary failure, and no deaths occurred in non-STCG. No significant correlations presented between STCs cumulative volumes and SOFA score (r = 0.096, p = .806; r = 0.067, p = .863; r = 0.024, p = .950).

Conclusion: Soft tissue calcifications detected on CT imaging following multiple Hymenoptera stings in pediatric patients may be a potential prognostic indicator of more severe complications and poorer outcomes.