Clinical Characteristics Of Community-acquired Pneumonia In Children Caused By Mycoplasma Pneumoniae

Background:Community-acquired pneumonia(CAP)is a lung parenchymal infection that occurs outside of the hospital.Mycoplasma pneumoniae(MP)is a bacterial pathogen that is one of the most often seen causes of community-acquired pneumonia.MP is a very prevalent pathogen causing respiratory diseases in kids and teenagers,responsible around 40%of CAP in children over the age of five years.Mycoplasma has been reported as the smallest prokaryote with no cell wall.Microbes are cell-free,flexible organisms that can develop and replicate in the absence of cells.We know that mycoplasma pneumoniae can cause an immune response that damages the respiratory epithelium and cilia.The human body produces a variety of inflammatory factors in response to a mycoplasma pneumoniae infection via activating immune cells.Typically,pneumonia is acquired in the community,and its presentation varies with disease progression.Complaints such as low-grade fever,sore throat headache,and malaise,may be present upon gradual onset of illness.Wet or dry cough is common,and it may be accompanied by pleuritic chest pain or shortness of breath.In clinical practice,MP bloodstream infection is widespread,and this infection might contribute to a role in the development of extrapulmonary mycoplasma pneumoniae-associated illnesses.MP is thought to spread to other organs via the circulation,causing damage to other organs.These infections may progress to mycoplasma pneumoniae pneumonia(MPP),with complications including pleural effusion,plastic bronchitis,and atelectasis in the acute phase,as well as necrotizing pneumonia,pulmonary thromboembolism,and lung abscess.MPP is challenging to identify or differentiate solely on clinical signs.In this regard,the lab test is especially helpful in the diagnosis of mycoplasma pneumoniae.Techniques for detecting mycoplasma pneumoniae in the laboratory include culture,serology,and nucleic acid amplification.A positive serology MP-Ig M antibody test and a nasopharyngeal swab that tested positive for MP-DNA on polymerase chain reaction(PCR)testing led to the infection’s diagnosis.In the case of MP-Ig M>1.1 COI was regarded positive,0.9 COI was considered negative,and MP-Ig M between 0.9 and 1.1 COI was considered weakly negative.The primary therapeutic treatment for mycoplasma pneumonia in children is drug therapy.At the moment,macrolide antibiotics are the most often utilized medications.Azithromycin and erythromycin are macrolide medicines that are effective against mycoplasma.Research purpose:This study aims to assess the differences in clinical characteristics of children diagnosed with CAP caused by MP and to further identify the cohort of patients who developed MP-induced myocardial damage as well as those without myocardial damage.Methods:This work is a retrospective study.We identified children between 2 months and 16years of age with clinical and radiological findings consistent with CAP.We admitted patients to the inpatient department of the Second Hospital of Jilin University,Changchun,China,from January 2019 to December 2019.Inclusion criteria:(1)Age between 2 months and 16years old;(2)Children admitted to the inpatient pediatric department of the Second Hospital of Jilin University during 2019 with diagnosed MPP;(3)Radiological findings such as interstitial infiltration,linear opacities,patchy infiltration,segmental or lobar consolidation,reticulonodular infiltrate or pleural effusion;(4)Diagnosed with MP by serology with an immunoglobulin M(Ig M)titer of>1.1COI considered positive.Exclusion criteria:(1)Children with chronic respiratory tract infection;(2)Community-acquired pneumonia caused by other species like chlamydia pneumonia;(3)The number of children with MP infection during Covid-19 is small,therefore,this data excludes children with MPP between 2020-2022.Clinical data were collected uniformly from the Second Hospital of Jilin University pediatrics inpatient department database.Based on the following symptoms,all patients were diagnosed with community-acquired pneumonia(CAP):cough,tachypnea,chest retractions,fever,wheezing,crackles or reduced breath sounds,and radiological abnormalities.The data was populated in Microsoft Excel 2016.Categorical data and comparison among groups of sex between mild and severe MPP were analyzed using the chi-squared or fisher’s exact tests((?)~2).An independent T-Test was used for normally distributed numerical variables.Statistical analyses were done through IBM SPSS statistics26.0,and a statistical significance was set at a P-value of＜0.05.Results were presented as mean±standard deviation (?)±SD for numerical variables.Results:A total of 409 hospitalized patients were diagnosed with MPP.Among them were214(52.3%)males and 195(47.7%)females.In mild MPP cases,232 patients were<5years,accounting for 77.6%:67 patients who were≥5 years,accounting for 22.4%.In severe MPP cases,85 patients were<5 years,accounting for 77.3%,and 25 patients were≥5 years,accounting for 22.7%.The seasonal distribution of hospitalized children with mild MPP 102/299(34.10%)and severe MPP indicated that 41/110(37.30%)were diagnosed during winter while mild MPP 80/299(26.80%)and severe MPP28/110(25.50%)patients were diagnosed during spring period.On the other hand,mild MPP 28/299(9.40%)and severe MPP 28/110(10.00%)patients were diagnosed during summer whereas mild MPP cases 89/299(29.80%)and severe MPP 30/110(27.30)patients were diagnosed during autumn.These results indicated that the incidence rate of mycoplasma pneumoniae in hospitalized children was highest in winter.The duration of fever and cough was the longest in severe MPP cases.Similarly,plasma levels of highly sensitive C-reactive protein(HSCRP)(t=-2.834,P<0.05),alanine transaminase(t=-2.511,P<0.05),aspartate aminotransferase(t=-2.939,P<0.05),and lactate dehydrogenase(LDH)(t=-2.939,P<0.05),creatine kinase isoenzyme(CK-MB)(t=-3.72,P<0.05),a-hydroxybutyrate dehydrogenase(HBDH)(t=-3.25,P<0.05),were also significantly higher in severe MPP cases than in mild MPP cases.Conversely,the neutrophil percentage was significantly lower in severe MPP cases than in mild MPP.Among the 409 patients,52patients were identified with myocardial damage,while 357 patients were identified without myocardial damage.The incidence of myocardial damage was 12%.From the 52patients with myocardial damage,23 patients(44.2%)were found with abnormal ECG changes such as(ST-T wave changes,QRS wave low voltage,sinus tachycardia or sinus bradycardia).The incidence of myocardial damage was higher and statistically significant in severe MPP cases than in mild(χ~2=157.078,P<0.05).Conclusions:Mycoplasma pneumoniae is the main cause of community-acquired pneumonia in hospitalized children.Children<5 years of age were most likely to have severe MPP than children≥5 years of age.We found a significantly higher incidence of myocardial damage in children with severe MPP than with mild MPP.However,it is unknown whether there is a causal link between Severe MPP and myocardial damage.