Increased procalcitonin level is a risk factor for prolonged fever in children with Mycoplasma pneumonia

Correlation of DNA load, genotyping, and clinical phenotype of Mycoplasma pneumoniae infection in children

Introduction

This study aimed to investigate the correlation between Mycoplasma pneumoniae (MP)-DNA load in the bronchoalveolar lavage fluid (BALF) of children with MP pneumonia (MPP) and its subtypes, relevant laboratory data, imaging, extrapulmonary complications in infected children, and its clinical significance in evaluating the disease.

Methods

Children hospitalized with MPP at Tianjin Children's Hospital between December 2017 and December 2020 were selected for the study, excluding those with mixed viral, bacterial, and fungal infections. Children were divided into low- and high-load groups according to the MP DNA load in BALF using real-time quantitative fluorescence polymerase chain reaction (PCR). After a successful MP culture, positive specimens were subjected to PCR-Restriction fragment length polymorphism and Multiple-locus variable number tandem repeat analysis typing. Basic data, clinical information, laboratory data, and radiological results were collected from all children included in the study.

Results

The PI-I type dominated the different load groups. Children in the low-load group had more wheezing and shortness of breath; however, children in the high-load group had a higher length of hospitalization, maximum fever temperature, higher chills/chilliness, incidence of abdominal pain, and higher C-reactive protein (CRP), procalcitonin (PCT) and aspartate aminotransferase (AST) levels. Children in the high-load group were more likely to have imaging changes such as pleural effusion, and the incidence of respiratory infections and extrapulmonary complications was higher than that of those in the low-load group. We applied Spearman's correlation analysis to clarify the relationship between MP DNA load and the clinical severity of MPP. We found that MP DNA load was positively correlated with length of hospitalization, maximum fever temperature, CRP, PCT, Interleukin-6 (IL-6), and AST levels, and negatively correlated with fever and cough durations, white blood cell count (WBC), and proportion of monocytes (MONO). The degree of correlation was as follows: length of hospitalization > IL-6 > cough duration > AST > fever duration > PCT > WBC > proportion of MONO > maximum fever temperature > CRP levels.

Conclusions

MP DNA load was not correlated with MP typing but was significantly correlated with the children's clinical phenotype. Therefore, the MP DNA load helps in the early diagnosis of infection and can better predict disease regression.

Clinical, Laboratory, and Radiographic Features Can Help Predict Mycoplasma pneumoniae Lower Respiratory Tract Infection in Children

Mycoplasma pneumoniae (Mp) is a common cause of lower respiratory tract infection (LRTI) in children that is difficult to distinguish from LRTI of other etiologies. We aimed to determine if a combination of clinical, laboratory, and chest radiographic features can help identify patients at higher risk of Mp LRTI. We reviewed medical charts of children referred to our tertiary hospital with suspected acute mycoplasmal LRTI. Pharyngeal swabs obtained from patients were tested by Mp PCR. We compared epidemiological and clinical data of children with positive and negative Mp PCR results. In addition, a multivariable logistic regression analysis was performed to predict Mp LRTI based on the patient's age, duration of symptoms, presence of extrapulmonary manifestations, laboratory findings, and chest radiographic findings. We included 65 children with Mp PCR-negative and 49 with Mp PCR-positive LRTI and no viral co-detection. Children with Mp LRTI were older (median age 5.8 vs. 2.2 years, p < 0.001), had a longer duration of symptoms on referral (median 7 vs. 4 days, p < 0.001), and lower median WBC (9.9 vs. 12.7 × 10⁹/L, p < 0.001). On chest radiograph, unilateral infiltrates were more frequently observed in the Mp PCR-positive group (57.5% vs. 24.1%, p = 0.001). Age, duration of symptoms, and chest radiographic findings had the highest predictive value for Mp LRTI in a multivariable logistic regression model. Our analysis suggests that a combination of clinical, laboratory, and chest radiographic features can be used to assess the likelihood of Mp LRTI and assist in decision-making for which children need further tests or macrolide antibiotic treatment.

Effect of sea buckthorn extract on production performance, serum biochemical indexes, egg quality, and cholesterol deposition of laying ducks

The purpose of this experiment was to study the effect of sea buckthorn extract (SBE) supplementation on the production performance, serum biochemical indexes, egg quality, and cholesterol deposition of laying ducks. A total of 240 23-week-old laying ducks (female ducks) with similar body weight were randomly divided into four treatment groups with 6 replicates of 10 each. The experimental groups were fed diets supplemented with 0, 0.5, 1.0, and 1.5 g/kg of SBE, respectively. The results showed that the addition of 1.0 g/kg SBE to the diet had significant increase (P < 0.05) in average egg weight and feed conversion ratio. The inclusion of SBE showed the significant improvement (P < 0.05) in yolk weight, shell strength, egg white height and haugh unit. Ducks fed with 1.0 and 1.5 g/kg SBE displayed a significant decrease (P < 0.05) in yolk cholesterol. The significant improvements were observed in the contents of total amino acid essential amino acids, non-essential amino acids, umami amino acids, monounsaturated fatty acids, and docosahexenoic acids of eggs (P < 0.05) when supplemented with SBE. However, the contents of total saturated fatty acids, polyunsaturated fatty acids, n-3 polyunsaturated fatty acids and n-6 polyunsaturated fatty acids in eggs showed decrease when ducks fed with SBE diets (P < 0.05). SBE diets may reduce (P < 0.05) the levels of serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol, while increased (P < 0.05) the levels of serum superoxide dismutase, total antioxidant capacity, and glutathione catalase compared to the control. The levels of serum immunoglobulin G, immunoglobulin A and immunoglobulin M were improved in SBE diets (P < 0.05) in comparation to the control. The addition of SBE to diets can improve feed nutrient utilization, increase egg weight, optimaze egg quality and amino acid content in eggs, reduce blood lipids, improve fatty acid profile and yolk cholesterol in eggs, and increase antioxidant capacity and immunity in laying ducks.

Highly Expressed lncRNA GAS5 in the Serum of Children with Mycoplasma pneumoniae Pneumonia and Its Effect on LAMPs-Induced Apoptosis and Inflammation

The aim of the study was to explore the serum expression of long noncoding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) in Mycoplasma pneumoniae pneumonia (MPP) and its effect on lipid-associated membrane proteins (LAMPs)-induced apoptosis and inflammation. Totally, 56 children with MPP (MPP group) and 56 healthy children (NC group) were enrolled. lncRNA GAS5 expression was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Serum levels of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) were detected using ELISA, and the high mobility family protein B1 (HMGBl) was detected by qRT-PCR. The methylated binding protein 2 (MECP2) was inhibited by gene silencing, and the expression of MECP2, TNF-α, IL-6, HMGBl, p-p65, and p-IκBα was measured. lncRNA GAS5 and TNF-α, IL-6, and HMGBl in the peripheral blood of the MPP group were positively correlated (P < 0.05). The expression of TNF-α, IL-6, HMGBl, and lncRNA GAS5 showed a positive correlation with that of LAMPs. The GAS5-siRNA group showed an increased cell survival rate compared with the scrambled-RNAi group (P < 0.05) while showing decreased apoptosis and cell death rates (P < 0.05). In addition, the expression of IL-6, TNF-α, HMGBl, p-p65, and p-IκBα was significantly reduced (P < 0.05). lncRNA GAS5 is highly expressed in the serum of children with MPP and inhibits LAMPs-induced apoptosis and alveolar macrophage inflammation.

Prediction of Bronchopneumonia Inpatients' Total Hospitalization Expenses Based on BP Neural Network and Support Vector Machine Models

Objective

BP neural network (BPNN) model and support vector machine (SVM) model were used to predict the total hospitalization expenses of patients with bronchopneumonia.

Methods

A total of 355 patients with bronchopneumonia from January 2018 to December 2020 were collected and sorted out. The data set was randomly divided into a training set (n = 249) and a test set (n = 106) according to 7 : 3. The BPNN model and SVM model were constructed to analyze the predictors of total hospitalization expenses. The effectiveness was compared between these two prediction models.

Results

The top three influencing factors and their importance for predicting total hospitalization cost by the BPNN model were hospitalization days (0.477), age (0.154), and discharge department (0.083). The top 3 factors predicted by the SVM model were hospitalization days (0.215), age (0.196), and marital status (0.172). The area under the curve of these two models is 0.838 (95% CI: 0.755~0.921) and 0.889 (95% CI: 0.819~0.959), respectively.

Conclusion

Both the BPNN model and SVM model can predict the total hospitalization expenses of patients with bronchopneumonia, but the prediction effect of the SVM model is better than the BPNN model.

Clinical Significance of Pleural Effusion in Mycoplasma pneumoniae Pneumonia in Children

The clinical significance of pleural effusion in Mycoplasma pneumoniae (MP) pneumonia in children has not yet been elucidated. Herein, we investigated the clinical implications of pleural effusion in children with MP pneumonia. Overall, 150 children with MP pneumonia transferred to a tertiary hospital were enrolled in this study. Information on their clinical, laboratory, and radiological features was retrospectively obtained from medical chart reviews. In total, 24 (16.0%) children had pleural effusion at the time of admission. The duration of fever and length of hospitalization were significantly longer in the pleural effusion group than in the non-pleural effusion group. A significantly higher proportion of individuals in the pleural effusion group had a poor response to stepwise treatment for MP pneumonia. The mean C-reactive protein, lactate dehydrogenase, and aspartate aminotransferase levels were significantly higher in the pleural effusion group than in the non-pleural effusion group at admission. The prevalence of severe pneumonia, defined on the basis of the extent of pneumonic lesions on chest radiography, was higher in the pleural effusion group than in the non-pleural effusion group. However, there was no significant intergroup difference in the proportion of macrolide-resistant MP cases or respiratory viral coinfections. The presence of pleural effusion in children with MP pneumonia indicated a more severe clinical course and poor treatment response. The results of the present study would help in the creation of a therapeutic plan and prediction of the clinical course of MP pneumonia in children.

Early Confirmation of Mycoplasma pneumoniae Infection by Two Short-Term Serologic IgM Examination

The aim of the present study is to re-evaluate the clinical application of two-times serologic immunoglobulin M (IgM) tests using microparticle agglutination assay (MAA), an enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction (PCR) assay in diagnosing Mycoplasma pneumoniae (MP) infection. A retrospective analysis of 62 children with MP pneumonia during a recent epidemic (2019–2020) was conducted. The MAA and ELISA immunoglobulin M (IgM) and IgG measurements were conducted twice at admission and around discharge, and MP PCR once at presentation. Diagnostic rates in each test were calculated at presentation and at discharge. The seroconverters were 39% (24/62) of patients tested by MAA and 29% (18/62) by ELISA. At presentation, the diagnostic positive rates of MAA, ELISA, and PCR tests were 61%, 71%, and 52%, respectively. After the second examination, the rates were 100% in both serologic tests. There were positive correlations between the titers of MAA and the IgM values of ELISA. The single serologic IgM or PCR tests had limitations to select patients infected with MP in the early stage. The short-term, paired IgM serologic tests during hospitalization can reduce patient-selection bias in MP infection studies.

[Clinical features of children with Mycoplasma pneumoniae pneumonia and peripheral lymphocytopenia]

OBJECTIVE

To study the clinical features of children with Mycoplasma pneumoniae pneumonia (MPP) and peripheral lymphocytopenia.

METHODS

A total of 310 MPP children who were hospitalized and underwent bronchoalveolar lavage from June 2018 to June 2019 were enrolled and divided into two groups: simple MPP group with 241 children (without peripheral lymphocytopenia) and MPP + peripheral lymphocytopenia group with 69 children. The two groups were compared in terms of clinical data and treatment outcome.

RESULTS

Compared with the simple MPP group, the MPP + peripheral lymphocytopenia group had significantly longer duration of fever and length of hospital stay and significant increases in C-reactive protein, lactate dehydrogenase, and Mycoplasma pneumoniae DNA copies in bronchoalveolar lavage fluid (P < 0.05). Compared with the simple MPP group, the MPP + peripheral lymphocytopenia group had significantly higher incidence rates of intrapulmonary consolidation, extrapulmonary complications, and serious lesions under bronchoscopy (erosion or sputum bolt) and a significantly higher proportion of patients with severe MPP (P < 0.05).

CONCLUSIONS

Children with MPP and peripheral lymphocytopenia tend to have more severe immunologic injury. Peripheral blood lymphocyte count may be used to evaluate the severity of MPP.

Mycoplasma pneumoniae: Atypical Pathogen in Community Acquired Pneumonia

Mycoplasma pneumoniae is a one of most common reasons of respiratory tract infections in both adolescents and children with severity ranged from moderate to high. Many facts in the previous years regarding infections were induced via this organism having extra pathogenic mechanisms. Clinically, resistance to macrolide has produced internationally and represents a treatment trouble. Antimicrobial sensitivity checking out techniques have been applied, and novel antibiotics which are effective towards M. pneumoniae are present processing development. That evaluate concentrates on the several trends occurring in the previous quite a few years which beautify the grasp of that microorganism, which is one of the smallest pathogenic bacteria; however, is of extreme medical significance.

Improved Diagnostics Help to Identify Clinical Features and Biomarkers That Predict Mycoplasma pneumoniae Community-acquired Pneumonia in Children

BACKGROUND

There are no reliable signs or symptoms that differentiate Mycoplasma pneumoniae (Mp) infection in community-acquired pneumonia (CAP) from other etiologies. Additionally, current diagnostic tests do not reliably distinguish between Mp infection and carriage. We previously determined that the measurement of Mp-specific immunoglobulin M antibody-secreting cells (ASCs) by enzyme-linked immunospot assay allowed for differentiation between infection and carriage. Using this new diagnostic test, we aimed to identify clinical and laboratory features associated with Mp infection.

METHODS

This is a prospective cohort study of children, 3-18 years of age, with CAP from 2016 to 2017. Clinical features and biomarkers were compared between Mp-positive and -negative groups by Mann-Whitney U test or Fisher exact test, as appropriate. Area under the receiver operating characteristic curve (AUC) differences and optimal thresholds were determined by using the DeLong test and Youden J statistic, respectively.

RESULTS

Of 63 CAP patients, 29 were Mp-positive (46%). Mp positivity was statistically associated with older age (median, 8.6 vs 4.7 years), no underlying disease, family with respiratory symptoms, prior antibiotic treatment, prolonged prodromal respiratory symptoms and fever, and extrapulmonary (skin) manifestations. Lower levels of C-reactive protein, white blood cell count, absolute neutrophil count, and procalcitonin (PCT), specifically PCT <0.25 μg/L, were statistically associated with Mp infection. A combination of age >5 years (AUC = 0.77), prodromal fever and respiratory symptoms >6 days (AUC = 0.79), and PCT <0.25 μg/L (AUC = 0.81) improved diagnostic performance (AUC = 0.90) (P = .05).

CONCLUSIONS

A combination of clinical features and biomarkers may aid physicians in identifying patients at high risk for Mp CAP.