Early risk factors for re-detectable positive in the recovered COVID-19 children

Background and Objective: Compared with adult patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), children have a higher proportion of re-detectable positive (RP) in the recovery period.The underlying risk factors remain unknown.We aimed to identify the early risk factors for RP, and to provide a basis for early clinical prediction and risk stratification. Methods: A retrospective analysis was performed on all pediatric cases diagnosed with coronavirus disease 2019 (COVID-19). Results: 14 of 38 (36.8%) pediatric patients were RP.Children have a significantly higher percentage of RP (OR[95%CI] 4.84[2.21-10.59];P=.000).Compared with control group (n=24),RP group (n=14) had more family cluster infections (1.59[1.1-2.3];P=.030),while age ([7.2±4.8] vs [7.6±5.1]),and percentage of male gender (35.7% vs 45.8%), fever (21.4% vs 45.8%),respiratory or digestive symptoms (71.4% vs 50%), asymptom (28.6% vs 33.3%), computed tomography positive findings (85.7% vs 83.3%) and co-infection (7.1% vs 8.3%) were statistically nonsignificant.The laboratory data of RP group had a relatively higher white blood cell count (WBC) (7.5[5.1-9.8] vs 4.8[4.4-7.5];P=.009) and longer plasma prothrombin time (PT) ([12.6±0.7] vs [12.1±0.5];P=.023),while neutrophil percentage and count, lymphocyte percentage and count, hemoglobin, platelets,erythrocyte sedimentation rate,high sensitivity C-reactive protein, interleukin 6,procalcitonin, activated partial thromboplastin time ([37.5±4.6] vs [34.2±5.1]; P=.057),fibrinogen,antithrombin III and D-dimer showed no statistical difference. Conclusions:Family cluster infection,higher WBC and longer PT are the main risk factors for RP in the recovered COVID-19 children.Early activation of coagulation and WBC may be involved in SARS-CoV-2 clearance.