[Application of Mycoplasma pneumoniae antibody and load index in the diagnosis of Mycoplasma pneumoniae pneumonia in children].

OBJECTIVE: To study the role of Mycoplasma pneumoniae (MP) load and antibody measurements in the diagnosis of MP pneumonia. METHODS: A total of 115 children with MP pneumonia and 400 healthy children were enrolled. The MP load and total antibody level were measured at different stages, and the MP load index (MPLI) was calculated. RESULTS: The cut-off value of MPLI for MP infection was 6.12. MPLI and total antibody titer increased during the course of the disease, while MP-DNA decreased rapidly. Within the same time of blood collection, the group with a higher MP load had a significantly higher total antibody titer than the group with a lower MP load (P<0.05). Within 2 weeks of the course of the disease, the negative antibody group had a significantly higher MPLI than the positive antibody group (P<0.05). CONCLUSIONS: MPLI provides a standardized quantitative value of MP-DNA and plays an important role in the early diagnosis of MP infection.

[Determination of resting energy expenditure in critically ill children experiencing mechanical ventilation].

OBJECTIVE: Energy metabolism of critically ill children has its own characteristics, especially for those undergoing mechanical ventilation. We tried to assess the energy expenditure status and evaluate the use of predictive equations in such children. Moreover, the characteristics of the energy metabolism among various situation were explored. METHOD: Fifty critically ill children undergoing mechanical ventilation were selected in this study. Data produced during the 24 hours of mechanical ventilation were collected for computation of severity of illness. Resting energy expenditure (REE) was determined at 24 hours after mechanical ventilation (MREE). Predictive resting energy expenditure (PREE) was calculated for each subject using age-appropriate equations (Schofield-HTWT, White). The study was approved by the hospital medical ethics committee and obtained parental written informed consent. RESULT: The pediatric risk of mortality score 3 (PRISM3) and pediatric critical illness score (PCIS) were (7 ± 3) and (82 ± 4), respectively. MREE, Schofield-HTWT equation PREE and White equation PREE were (404.80 ± 178.28), (462.82 ± 160.38) and (427.97 ± 152.30) kcal/d, respectively; 70% were hypometabolic and 10% were hypermetabolic. MREE and PREE which were calculated using Schofield-HTWT equation and White equation, both were higher than MREE (P = 0.029). Correlation analysis was performed between PRISM3 and PCIS with MREE. There were no statistically significant correlation (P > 0.05). CONCLUSION: The hypometabolic response is apparent in critically ill children with mechanical ventilation; Schofield-HTWT equation and White equation could not predict energy requirements within acceptable clinical accuracy. In critically ill children undergoing mechanical ventilation, the energy expenditure is not correlated with the severity of illness.