Yixin Ren, Y Yanliu Lin, Jihong Dai
BACKGROUND: Fulminant Mycoplasma pneumoniae pneumonia (FMPP) represents a life-threatening progression of typical Mycoplasma pneumoniae pneumonia (MPP) in pediatric patients. This study aimed to identify the risk factors and clinical characteristics associated with FMPP complicated by respiratory failure in children, thereby facilitating early recognition and timely intervention. METHODS: A retrospective case–control study was conducted involving 66 children with FMPP and 217 children with non-fulminant Mycoplasma pneumoniae pneumonia (NFMPP) who were admitted to the Department of Respiratory Medicine and the Intensive Care Unit of the Children’s Hospital Affiliated with Chongqing Medical University between January and December 2023. Cox regression analysis was performed to identify independent risk factors for FMPP. Propensity score matching (PSM) was applied to balance baseline risk factors, followed by a comparative analysis of clinical characteristics between the matched FMPP group (n = 62) and the matched NFMPP group (n = 116). RESULTS: Wheezing, a Mycoplasma pneumoniae load ≥ 1.7 × 10⁷ copies/mL, and pulmonary consolidation were independently associated with FMPP, whereas concomitant Epstein-Barr virus infection and β-lactam treatment for ≥ 3 days were inversely associated. After PSM, children with FMPP more frequently presented with fine crackles and wheezing and had higher rates of atelectasis and neurological complications. Compared with NFMPP cases, FMPP was characterized by increased peripheral blood and bronchoalveolar lavage neutrophil proportions and elevated liver enzyme levels, along with lower fibrinogen, total protein, albumin, and interferon-γ levels. In multivariable analysis, fine crackles, peripheral blood neutrophil percentage, and fibrinogen level remained independently associated with FMPP. Clinically, children with FMPP required more frequent escalation to second-line antimycoplasma therapy, β-lactam antibiotics, and glucocorticoids and experienced longer hospital stays; however, all patients recovered without mortality. CONCLUSION: Wheezing, a high Mycoplasma pneumoniae load, and pulmonary consolidation are independent risk factors for FMPP, whereas Epstein-Barr virus coinfection and early β-lactam therapy may mitigate disease progression. Although FMPP is characterized by severe systemic inflammation and multiorgan involvement, prompt and appropriate management can lead to favourable clinical outcomes. CLINICAL TRIAL NUMBER: Not applicable.