Unresolved atelectasis in refractory Mycoplasma pneumoniae pneumonia: Predictive factors and the influence of corticosteroids and bronchoscopy lavage therapy

Abstract Background Unresolved atelectasis occurs in some children with refractory mycoplasma pneumoniae pneumonia (RMPP). The aim was to analyze factors predicting unresolved atelectasis in RMPP and the impact of corticosteroids and bronchoscopy lavage therapy (BLT) on developing atelectasis.Methods We retrospectively analyzed data for 230 pediatric RMPP from January 2013 to June 2017 in Beijing Children’s Hospital. In this study, we diagnosed RMPP when patients' clinical and radiological findings deteriorated after 7 days of macrolide therapy, peripheral blood C-reactive protein (CRP) was higher than 40mg/L, and chest imaging showed consolidation with high density > 1/2 pulmonary lobe. We divided patients into two groups according to the presence/absence of atelectasis on chest imaging after a 6-month follow-up. We calculated the predictive value of fever duration, levels of CRP and lactate dehydrogenase (LDH), and the size of lobe consolidation, regarding atelectasis. Additionally, we compared the starting time and dosage of corticosteroids and the starting time of BLT between the two groups.Results Ninety-five patients developed atelectasis (atelectasis group/group A), and 135 patients did not (non-atelectasis group/group NA). Chest imaging showed > 2/3 pulmonary lobe consolidation in 93.7% of patients in group A and 54.1% of patients in group NA. Multiple logistic regression analysis showed that fever duration, CRP and LDH levels, and lobe consolidation were related to developing atelectasis. Areas under the curve revealed that CRP ≥ 137 mg/L had 82.11% sensitivity and 80.07% specificity, and LDH ≥ 471 IU/L had 62.65% sensitivity and 60.31% specificity to predict atelectasis. Fewer patients receiving corticosteroids and BLT within 10 days after illness onset developed atelectasis.Conclusions Fever duration>10 days, CRP and LDH levels, and lobe consolidation are risk factors for developing atelectasis in RMPP. CRP ≥ 137 mg/L, LDH ≥ 471 IU/L, and >2/3 pulmonary lobe consolidation were significant predictors of atelectasis, which can aid in early recognition. Corticosteroid administration and subsequent BLT within 10 days of the disease onset, and increased corticosteroid dosage may help reduce the incidence of atelectasis in these RMPP patients.