Background: Mycoplasma pneumoniae pneumonia (MPP) is common among children, but the impact of atopy on MPP severity in children is unknown. This study investigated whether atopic vs. nonatopic children had greater MPP severity. Methods: Of 539 children (ages 3-14 years) diagnosed with MPP between January 2018 and December 2021 in the First Affiliated Hospital of Anhui Medical University and enrolled in this study, 195 were atopic and 344 were nonatopic. Of them, 204 had refractory MPP, and 335 had general MPP. Data on demographic and clinical characteristics, laboratory findings, clinical treatments, lung function, and fibrobronchoscopy results were analyzed. Results: Significantly more boys with MPP were atopic than nonatopic ( P<0.05). More atopic (than nonatopic) children presented with prolonged fever and hospitalization, severe extra-pulmonary complications, steroid treatment, wheezing, and increased IgE levels (all P<0.05). In atopic (vs. nonatopic) children with MPP, the incidence of mucosal inflammation with lymphoid follicular hyperplasia and segmental pneumonia was significantly increased and required bronchoscopy-assisted and steroid therapy. Compared with nonatopic children, more atopic children developed refractory MPP ( P<0.05). Prolonged fever and hospitalization, severe extra-pulmonary complications, lymphocyte count, procalcitonin and lactate dehydrogenase levels, and percentages of atopy were all significantly higher ( P<0.05) among children with refractory MPP vs. general MPP. Spearman correlation analysis showed strong associations between atopy and male sex, length of hospital stay, fever duration, IgE level, wheezing, segmental pneumonia, refractory MPP, and treatment with hormones or bronchoscopy ( P<0.05). Conclusions: Atopy may be a risk factor for and was positively correlated with the severity of MPP in children.

Objective: Untreated protracted bacterial bronchitis (PBB), a chronic wet cough prevalent in children, may lead to chronic suppurative lung disease or bronchiectasis. However, clinical diagnostic criteria for PBB are nonspecific; thus, PBB may be misdiagnosed. Thus, we assessed the diagnostic value of fiberoptic bronchoscopy (FOB) and risk factors associated with PBB. Methods: Children with chronic cough at First Affiliated Hospital of Anhui Medical University from January 2015 to May 2020 were enrolled and allocated to a suspected PBB (n=141) or a non-PBB (n=206) group. All children underwent extensive laboratory, chest imaging, and allergen tests. Children with suspected PBB underwent FOB with bronchoalveolar lavage; lavage and sputum samples were cultured. Results: All 347 children had chronic wet cough for approximately 2 months. Of 141 children with suspected PBB, 140 received FOB with bronchoalveolar lavage. Visible tracheal changes included pale mucosa, mucosal congestion, edema, swelling, and increased secretions attached to the wall. Sputum was visible primarily in the left main bronchus (78.7%), left lower lobe (59.6%), right upper lobe (62.4%), and right lower lobe (64.5%). Sputum properties and amounts significantly differed between children with vs. without PBB ( P < 0.05). Dermatophagoides (odds ratio [OR], 2.642; 95% CI, 1.283–5.369) and milk protein (OR, 2.452; 95% CI, 1.243–4.836) allergies and eczema (OR, 1.763; 95% CI, 1.011–3.075) were risk factors significantly associated with PBB. Conclusion: Dermatophagoides, milk protein, and eczema were associated with increased risk of PBB. Sputum distribution and tracheal wall changes observed through FOB may distinguish PBB and assist in its diagnosis.