Annual and seasonal patterns in etiologies of pediatric community-acquired pneumonia due to respiratory viruses and Mycoplasma pneumoniae requiring hospitalization in South Korea

Abstract

Background: Community–acquired pneumonia (CAP) is one of the leading worldwide causes of childhood morbidity and mortality. Its disease burden varies by age and etiology and is time dependent. We aimed to investigate the annual and seasonal patterns in etiologies of pediatric CAP requiring hospitalization. Methods: We conducted a retrospective study in 30,994 children (aged 0-18 years) with CAP between 2010 and 2015 at 23 nationwide hospitals in South Korea. Mycoplasma pneumoniae (MP) pneumonia was clinically classified as macrolide-sensitive MP, macrolide-less effective MP (MLEP), and macrolide-refractory MP (MRMP) based on fever duration after initiation of macrolide treatment, regardless of the results of in vitro macrolide sensitivity tests. Results: MP and respiratory syncytial virus (RSV) were the two most commonly identified pathogens of CAP. With the two epidemics of MP pneumonia (2011 and 2015), the rates of clinical MLEP and MRMP pneumonia showed increasing trends of 36.4% of the total MP pneumonia. In children < 2 years of age, RSV (34.0%) was the most common cause of CAP, followed by MP (9.4%); however, MP was the most common cause of CAP in children aged 2-18 years of age (45.3%). Systemic corticosteroid was most commonly administered for MP pneumonia. The rate of hospitalization in intensive care units was the highest for RSV pneumonia, and ventilator care was most commonly needed in cases of adenovirus pneumonia. Conclusions: The present study provides fundamental data to establish public health policies to decrease the disease burden due to CAP and improve of pediatric health.

Predictive Factors of the Responses to Treatment of Mycoplasma pneumoniae Pneumonia

“…Mycoplasma pneumoniae (MP) is one of the most common causes of community-acquired pneumonia in children, with its cyclic epidemics occurring every three to four years, depending on the geographic location [ 1 , 2 ]. MP can spread via infectious droplets, and the estimated incubation period is between four days and three weeks.…”

“…MP can spread via infectious droplets, and the estimated incubation period is between four days and three weeks. MP is characterized by the absence of cell-wall material; hence, only a few antibiotics are effective against MP infection [ 1 , 2 ]. Although MP infection is considered to be a self-limiting disease in some cases, potentially severe MP pneumonia cases, characterized by poor response to the first-line therapy—which consists of a 7- to 14-day treatment of clarithromycin (10–15 mg/kg/day, 2–3 doses, orally) or a three-day treatment of azithromycin (10 mg/kg/day, once daily, orally)—and incomplete resolution of pulmonary lesions, are increasing [ 3 ].…”

“…In cases of refractory MP pneumonia, usually defined as clinical and radiologic deterioration despite appropriate treatment for seven days or more [ 1 , 6 , 7 , 8 ], the risk of developing complications, such as persistent pulmonary atelectasis, consolidation, or post-infectious bronchiolitis obliterans, is increased [ 9 ]. In clinical situations, MP pneumonia cases, with poor response to treatments, including macrolides, floxacins, tetracyclines, or glucocorticoids, result in increased medical care costs and socioeconomic burdens.…”