Mycoplasma pneumoniae and Viral Pneumonia Coinfection: Something NOT to be Overlooked

This is the authors' abstract. We don't add key points for this paper.

To the Editors: We have read with great interest the recent publication by Guo et al,1 which analyzed the differences in clinical characteristics between Mycoplasma pneumoniae pneumonia (MPP) and viral pneumonia. The authors included 210 pediatric patients with community-acquired pneumonia (CAP) and reported significant differences in symptomatology (fever and vomiting) and investigation results between the MPP and viral pneumonia groups. The MPP group also had a higher disease burden and required more intensive monitoring. It is noteworthy that patients with coinfections were excluded in this study. Coinfections with more than one causative pathogen in pediatric CAP were not uncommon. Jiang et al2 reported that coinfection was identified in more than one-third of patients with CAP, and the majority had a combination of viral and bacterial infections. In a 2-year analysis in our center, we managed 142 pediatric patients diagnosed with Mycoplasma pneumoniae infections. Of these, 123 of them had CAP, while the remaining had other diagnoses including upper respiratory tract infections and encephalopathies. The mean (standard deviation) age of the CAP cohort was 6.8 ± 3.8 years old. Nasopharyngeal swabs were obtained for respiratory viral panels in all patients, which revealed coexisting viral infections in 16 (13%) of them. These included enterovirus/rhinovirus (n = 9), adenovirus (n = 3), respiratory syncytial virus (n = 2), influenza B (n = 1) and parainfluenza (n = 1) infections. In comparison to those without respiratory coinfection, our cohort showed a higher prevalence of rhinorrhea in the coinfection group (75% vs. 41%, P = 0.015). However, there were no significant differences in other symptoms such as fever, cough, sputum production, sore throat, vomiting, diarrhea and dermatological manifestations. Furthermore, patients with viral coinfection had worse outcomes, as indicated by a higher likelihood of pediatric intensive care unit admission (19% vs. 3%, P = 0.029), oxygen therapy requirement (56% vs. 25%, P = 0.017), mechanical ventilation (13% vs. 1%, P = 0.044) and a longer hospital stay [median 4 (interquartile range, 3–11) vs. 3 (interquartile range, 2–5) days, P = 0.022]. The incidence of MPP had drastically decreased during the COVID-19 pandemic, likely attributed to the widespread implementation of nonpharmaceutical interventions during the years.3 However, in recent months, there has been a notable upsurge of MPP cases across different regions.4 In addition, owing to the reduced global population exposure to Mycoplasma in the preceding years, the resurgence of MPP may also be associated with increased extrapulmonary manifestations with a more severe disease spectrum.3 Given the possible detrimental effects of coinfections, early detection of coexisting viral infections and high vigilance for atypical extrapulmonary manifestations become crucial for effective risk stratification and timely interventions to improve clinical outcomes in these patients.