The comparisons of procalcitonin and age between mild and severe Hand, foot, and mouth disease

Background: Hand, foot, and mouth disease (HFMD) is an epidemic infectious disease in children, usually associated with fever, mouth lesions, and limb rashes. Although benign and self-limiting, it can be dangerous or even fatal in rare cases. Early identification of severe cases is crucial to ensure optimal care. Procalcitonin (PCT) is an early marker for predicting sepsis. Therefore, in this study, we aimed to investigate the significance of PCT levels, age, lymphocyte subsets, N-terminal pro-brain natriuretic peptide (BNP) in the early diagnosis of severe HFMD. Methods: Using strict inclusion and exclusion criteria, we retrospectively enrolled 183 children with HFMD between January 2020 and August 2021 and divided them into mild (76 cases) and severe (107 cases) groups according to their condition. Data on the patients' PCT levels, lymphocyte subsets, and clinical characteristics at admission were evaluated and compared using the Student's t-test and chi(2) test. Results: We found that compared with mild disease forms, the severe disease forms were associated with higher blood PCT levels (P=0.001) and lower ages of onset ( P<0.001). The percentages of lymphocyte subsets, including suppressor T cells (CD3(+)CD8(+)), T lymphocytes ( CD3(+)), T helper cells (CD3(+)CD4(+)), natural killer cells (CD16(+)56(+)), and B lymphocytes (CD19(+)), were identical between the two disease forms in patients under 3 years of age. Conclusions: Age and blood PCT levels play a vital role in the early identification of severe HFMD.