G412(P) Influenza in children: is there a pattern of adverse outcomes and are inflammatory markers predictive?

Influenza is generally a self-limiting disease (1), however, complications can occur (2). We examined whether there is link between influenza strains in children and length of hospital stay (LOS), transfer to ICU, mortality, secondary bacterial infection (SBI) or peripheral blood tests. We studied141 patients attended our hospital between November 2017 and March 2018; influenza A was reported in 80 (56.7%), influenza B in 60 (42.6%) and both strains in one. Mean (SD) age was 5.12 (4.30) years. Statistically, patients were divided into two groups (influenza A and influenza B). Admission to paediatric ward was required in 91 patients (64.54%), of whom two required transfer to ICU (2.2%). No mortality was documented. Mean (SD) LOS was 2.33 (1.92) days, with no link between LOS and influenza viral strains (p value 0.35). Of 141 patients, 111 underwent blood tests. Of 111 patients, the majority had normal total WBC [72 patients (64.9%)] and neutrophil values [80 (72.1%)]. More than half had normal lymphocyte [61 patients (55.0%)] and monocyte values [64 (57.7%)]. However, total WBC, neutrophil, lymphocyte and monocyte values were elevated in 9 (8.1%), 19 (17.1%),two(1.8%) and 47 (42.3%) patients, respectively. Total WBC, neutrophil and lymphocyte values were lower than the reference range in 30 (27.0%), 12 (10.8%) and 48 (43.2%) patients, respectively. Total WBC, neutrophil, lymphocyte or monocyte values did not differ between the groups (p value 0.48, 0.52, 0.71 and 0.38, respectively). Combined abnormal WBC differentials were uncommon [5 of 111 patients (4.50%)]. In terms of predicting influenza strains, neutrophil lymphocyte ratio (NLR) and monocyte lymphocyte ratio (MLR) have low sensitivity, with area under the ROC curve 0.42 and 0.53, respectively. Mean (SD) C-reactive protein (CRP) value was 14.45 (10.12) mg/L, with no difference between the groups (p value 0.52). No organisms were detected in 79 patients who underwent peripheral blood culture. In conclusion, influenza can occur with normal WBC and CRP values. NLR or MLR has no role in predicting influenza serotypes. In this group of patients, the vast majority did not require transfer to ICU. Moreover, there is no link between influenza viral strains and LOS, mortality or SBI References 1. Mancinelli L, Onori M, Concato C, et al. Clinical features of children hospitalized with influenza A and B infections during the 2012–2013 influenza season in Italy. BMC Infect Dis. 2016 Jan 8;16:6. doi: 10.1186/s12879–015–1333-x Rothberg MB, Haessler SD. Complications of seasonal and pandemic influenza. Crit Care Med 2010; 38:e91.