Evaluation of serum high sensitive C-reactive protein, procalcitonin, neopterin and leukocyte on different respiratory infectious disease in Chinese children

Objective: To investigate serum high sensitive C-reactive protein (hs-CRP), procalcitonin (PCT), neopterin (NP) and leukocyte (WBC) on different pathogens of respiratory infectious disease, and to provide antibiotic therapy with favorable evidences in Chinese children in the region of guangdong. Methods: 438 infants and children were diagnosed and divided into normal bacterial infection (group A1), suppurative tonsillitis (group A2), mycoplasma (Mp) infection (group B) and virus infection (group C). 50 healthy children were taken as control. Serum hs-CRP, PCT, NP, WBC and blood routine were detected and compared in all groups before and after antibiotic therapy. Results: Serum hs-CRP (mg/L) was higher in A1 (11.55±9.31), A2 (46.38±40.17) and B (6.25±2.64) groups than in control (1.39±1.76) group, significantly (P<0.05). Serum PCT (ng/mL) was higher in A1 (1.33±6.90), A2 (1.41±4.31), B (0.26±4.98) and C (0.18±7.10) groups than in control (0.05±5.75) group, significantly (P<0.05). Serum NP (nmol/L) in A1 (19.05±8.94), A2 (35.86±12.76), B (33.75±10.44) and C (43.51±15.90) groups was higher than in control (6.67±3.32) group, significantly (P<0.05). Serum WBC (1×109/L) was higher in A1 (13.82±10.81) and A2 (13.64±10.55) groups than in control (7.45±3.30) group, significantly (P<0.05). The positive rate of hs-CRP in A1 (71.33%) and A2 (77.78%) groups were higher than in B (30.86%) and C (14.80%) group. The positive rate of PCT in A2 (100%) group was the highest; while in A1 (40.56%) group was higher than in B (32.10%) and C (17.35%) groups. The positive rate of NP in A1 (68.51%), A2 (72.22%), B (80.25%) and C (96.94%) increased gradually. The positive rate of WBC in A1 (51.75%) group was higher than in A2 (33.33%), B (34.57%) and C (15.31%) groups. The sensitivities and specificities of hs-CRP, PCT and WBC for bacterial respiratory infection were 72.05% and 100%, 47.20% and 98.00%, 49.69% and 96.00%, separately, while NP for viral were 96.94% and 100%. Conclusions: Detection of serum hs-CRP, PCT, NP and WBC was helpful for identification of bacterial, Mp pneumonia and virus infection. Using serum hs-CRP to evaluate bacterial respiratory infection was more sensitive than using serum PCT or WBC, independently, while using serum NP to evaluate viral respiratory infection was more sensitive. Combining serum hs-CRP, PCR, NP and WBC to evaluate different kinds of respiratory infection was more suitable clinically.