Application of peripheral blood routine parameters in the diagnosis of influenza and Mycoplasma pneumoniae.

OBJECTIVES: Influenza and Mycoplasma pneumoniae infections often present concurrent and overlapping symptoms in clinical manifestations, making it crucial to accurately differentiate between the two in clinical practice. Therefore, this study aims to explore the potential of using peripheral blood routine parameters to effectively distinguish between influenza and Mycoplasma pneumoniae infections. METHODS: This study selected 209 influenza patients (IV group) and 214 Mycoplasma pneumoniae patients (MP group) from September 2023 to January 2024 at Nansha Division, the First Affiliated Hospital of Sun Yat-sen University. We conducted a routine blood-related index test on all research subjects to develop a diagnostic model. For normally distributed parameters, we used the T-test, and for non-normally distributed parameters, we used the Wilcoxon test. RESULTS: Based on an area under the curve (AUC) threshold of ≥ 0.7, we selected indices such as Lym# (lymphocyte count), Eos# (eosinophil percentage), Mon% (monocyte percentage), PLT (platelet count), HFC# (high fluorescent cell count), and PLR (platelet to lymphocyte ratio) to construct the model. Based on these indicators, we constructed a diagnostic algorithm named IV@MP using the random forest method. CONCLUSIONS: The diagnostic algorithm demonstrated excellent diagnostic performance and was validated in a new population, with an AUC of 0.845. In addition, we developed a web tool to facilitate the diagnosis of influenza and Mycoplasma pneumoniae infections. The results of this study provide an effective tool for clinical practice, enabling physicians to accurately diagnose and differentiate between influenza and Mycoplasma pneumoniae infection, thereby offering patients more precise treatment plans.

Quantitative radiomics analysis of imaging features in adults and children Mycoplasma pneumonia.

Purpose: This study aims to explore the value of clinical features, CT imaging signs, and radiomics features in differentiating between adults and children with Mycoplasma pneumonia and seeking quantitative radiomic representations of CT imaging signs. Materials and methods: In a retrospective analysis of 981 cases of mycoplasmal pneumonia patients from November 2021 to December 2023, 590 internal data (adults:450, children: 140) randomly divided into a training set and a validation set with an 8:2 ratio and 391 external test data (adults:121; children:270) were included. Using univariate analysis, CT imaging signs and clinical features with significant differences (p < 0.05) were selected. After segmenting the lesion area on the CT image as the region of interest, 1,904 radiomic features were extracted. Then, Pearson correlation analysis (PCC) and the least absolute shrinkage and selection operator (LASSO) were used to select the radiomic features. Based on the selected features, multivariable logistic regression analysis was used to establish the clinical model, CT image model, radiomic model, and combined model. The predictive performance of each model was evaluated using ROC curves, AUC, sensitivity, specificity, accuracy, and precision. The AUC between each model was compared using the Delong test. Importantly, the radiomics features and quantitative and qualitative CT image features were analyzed using Pearson correlation analysis and analysis of variance, respectively. Results: For the individual model, the radiomics model, which was built using 45 selected features, achieved the highest AUCs in the training set, validation set, and external test set, which were 0.995 (0.992, 0.998), 0.952 (0.921, 0.978), and 0.969 (0.953, 0.982), respectively. In all models, the combined model achieved the highest AUCs, which were 0.996 (0.993, 0.998), 0.972 (0.942, 0.995), and 0.986 (0.976, 0.993) in the training set, validation set, and test set, respectively. In addition, we selected 11 radiomics features and CT image features with a correlation coefficient r greater than 0.35. Conclusion: The combined model has good diagnostic performance for differentiating between adults and children with mycoplasmal pneumonia, and different CT imaging signs are quantitatively represented by radiomics.

Recurrent Reactive Infectious Mucocutaneous Eruption in an Adult Male Secondary to Mycoplasma Infection: A Case Report.

Mycoplasma pneumoniae commonly causes respiratory tract infections but can also involve the skin and mucosal surfaces. Reactive infectious mucocutaneous eruption (RIME) secondary to mycoplasma infection is uncommon in adults but is an important clinical entity. We present the case of a 26-year-old male who experienced recurrent episodes of erythematous and painful oral ulcers without any prodromal or respiratory symptoms. Serological testing confirmed a recent mycoplasma infection. The patient was successfully treated with oral steroids and supportive therapy. This case underscores the challenges of diagnosing RIME, particularly in the absence of typical respiratory symptoms. Moreover, oral steroid therapy with supportive treatment may suffice to manage RIME if the patient lacks an ongoing infection or other underlying pathologies.

Diagnostic value of cytokines in severe childhood Mycoplasma pneumoniae pneumonia combined with Adenovirus infection.

BACKGROUND: To explore the alterations of inflammatory markers and immune-related cytokines in children infected with Mycoplasma pneumoniae (MP) combined with Adenovirus (ADV). METHODS: The study population consisted of 201 children with MPP, and they were grouped according to whether they were coinfected with ADV infection and critically ill. Additionally, comparative analyses were performed. The diagnostic value of different indicators and combined indicators for SMPP combined with ADV was assessed using ROC curves. RESULTS: There was no difference between group A1 and group A2, group B1 and group B2 in terms of age, gender, duration of hospitalisation and fever. The levels of calcitoninogen(PCT), lactate dehydrogenase concentration(LDH), interleukin(IL)-6, IL-8, IL-10, IL-4, IL-12P70, and IFN-γ in group A were higher than group B. The severe group (A1, B1) was significantly higher than the mild group (A2, B2) in terms of D-dimer, CRP, PCT, LDH, IL-6, IL-8, IL-10, IL-17a and number of patients with pleural effusion, solid lung changes. Among the individual indexes of D-dimer, CRP, N%,LDH, and PCT, the AUC of the combined test was 0.977, which was higher than that of the individual indicators. Among IL-6, IL-8, IL-10, and IL-17a, the AUC of the combined assay was 0.802, which was higher than that of the individual indicators. CONCLUSION: MP combined with ADV infection was associated with increased expression levels of IL-6, IL-8, IL-10, IL-4, IL-12P70, IFN-γ, and LDH. IL-6, IL-8, IL-10, IL-17a, LDH, PCT, CRP, and D-dimer could be used as predictors of SMPP and the combined test can improve the diagnostic value.

Navigating the Diagnostic Challenges of Mycoplasma and Legionella Coinfection Through Serological Testing.

Diagnosing community-acquired pneumonia (CAP) is increasingly challenging, especially with the emergence of atypical pathogens such as Mycoplasma pneumoniae and Legionella pneumophila. This report presents the case of a 60-year-old male exhibiting lethargy and decreased oral intake, with a medical history marked by chronic kidney disease and benign prostate hyperplasia. Despite a positive Legionella urine antigen, the clinical and radiological profile did not align with Legionella pneumonia. Elevated M. pneumoniae IgM antibody titers further complicated the diagnostic scenario. We explore the complexities of distinguishing coinfection from primary infection, highlight the limitations of serological testing, and promote a comprehensive diagnostic strategy customized to individual patient circumstances. This case emphasizes the importance of comprehensive assessment strategies to understand atypical pneumonia presentations, particularly within complex clinical scenarios.

Immunity debt: Hospitals need to be prepared in advance for multiple respiratory diseases that tend to co-occur.

As SARS-CoV-2 transitions from a pandemic to an endemic presence, a significant rise in respiratory diseases such as influenza and Mycoplasma pneumonia is challenging healthcare systems weakened by the impact of COVID-19. This commentary examines the global resurgence of respiratory pathogens, heightened by the post-pandemic "immunity debt", through an analysis of WHO surveillance data and national health reports. Findings reveal a substantial increase in respiratory illnesses, notably among children, compounded by a shortage of pediatricians and growing antimicrobial resistance. This underscores the need to improve hospital preparedness, optimize clinical responses, and enhance public health strategies to effectively navigate the impending peak of concurrent respiratory infections.

Chest imaging classification in Mycoplasma pneumoniae pneumonia is associated with its clinical features and outcomes.

BACKGROUND: The imaging findings of Mycoplasma pneumoniae pneumonia (MPP) vary; however, few studies have focused on the relationship of imaging classification with clinical manifestations and outcomes. OBJECTIVE: To prospectively investigate whether chest imaging classification in Mycoplasma pneumoniae pneumonia (MPP) is associated with its clinical features and outcomes. METHODS: A total of 1,401 hospitalized children with MPP were enrolled from January 2019 to December 2021. Imaging findings were categorized as bronchopneumonia and consolidation/atelectasis according to X-ray, and bronchopneumonia, consolidation/atelectasis, bronchiolitis, and mosaic pattern according to computed tomography (CT). Clinical characteristics and outcomes of patients with different imaging classifications were prospectively analyzed based on electronic medical records. RESULTS: Bronchopneumonia was the most common finding (59.6%), while consolidation/atelectasis was the most severe group. Clinical manifestations and laboratory indicators for the consolidation/atelectasis group included serious abnormalities. Further, outcomes of the patients were worse, including having longer total durations of fever and hospitalization, greater hospitalization expenses, and a higher likelihood of developing refractory MPP, necrotizing pneumonia, and bronchiolitis obliterans (BO) in this group. The incidence of bronchiolitis, a disease characterized by a high prevalence of fever, moist rales, and an atopic constitution, tended to increase after the coronavirus disease pandemic and predisposed patients to BO. A mosaic pattern occurred in allergic and young individuals, with wheezing as the main manifestation, with patients having relatively mild symptoms and good outcomes. CONCLUSION: Different imaging classifications have different clinical features and clinical outcomes; thus, formulating an imaging-based classification system is of great clinical value.

Coronary artery dilation in children with febrile illnesses other than Kawasaki disease: A case report and literature review.

Background: Coronary artery dilation (CAD) had rarely been described as a cardiac complication of febrile disease other than Kawasaki disease (KD). There are rare cases complicated by CAD reported in patients with Mycoplasma pneumoniae (MP) infection. Case presentation: A 6-year-old boy with severe Mycoplasma pneumoniae pneumonia (MPP) was transferred to our hospital due to significant respiratory distress on the 11th day from disease onset. Nadroparin, levofloxacin, and methylprednisolone followed by oral prednisone were aggressively prescribed. His clinical condition gradually achieved remission, and the drugs were withdrawn on the 27th day. Regrettably, the recurrent fever attacked him again in the absence of infection-toxic manifestations. Necrotizing pneumonia (NP) was found on chest CT. And echocardiography revealed right CAD (diameter, 3.40mm; z-score, 3.8), however, his clinical and laboratory findings did not meet the diagnostic criteria of KD. CAD was proposed to result from MP infection, and aspirin was prescribed. Encouragingly, the CAD regressed one week later (diameter, 2.50mm; z-score, 1.4). Additionally, the child defervesced seven days after the initiation of prednisone and Nadroparin treatment. The patient was ultimately discharged home on the 50th day. During follow-up, the child was uneventful with normal echocardiography and fully resolved chest CT lung lesions. Conclusions: CAD can develop in patients with severe MP infection. Pediatricians should be alert to the possibility of CAD in patients with severe MP infection and recognize that CAD might also develop in febrile disease rather than KD.

Clinical Efficacy of Ulinastatin Combined with Azithromycin in the Treatment of Severe Pneumonia in Children and the Effects on Inflammatory Cytokines and Oxidative Stress: A Retrospective Cohort Study.

Purpose: This retrospective cohort study aimed to evaluate the clinical efficacy of ulinastatin (UTI) and azithromycin (AZM) combination therapy in treating severe pneumonia in children and its impact on inflammatory cytokines and oxidative stress. Patients and Methods: This retrospective cohort study was conducted from January 1, 2019, to January 1, 2021, involving pediatric patients diagnosed with severe mycoplasma pneumonia (SMPP). The pediatric patients were divided into two groups: those receiving UTI and AZM combination therapy (treatment group) and those receiving azithromycin alone (control group). We compared the two groups regarding clinical data, disease outcomes, inflammatory cytokines, and oxidative stress levels. Results: Baseline characteristics did not significantly differ between the two groups. UTI, in combination with AZM, significantly improved blood oxygen levels, inflammatory infection markers, and relevant clinical symptoms in patients with SMPP on the 3rd day of treatment. Additionally, it significantly reduced the levels of inflammatory cytokines TNF-a, IL-6, IL-1ß, and IL-10, as well as oxidative stress markers GSH and SOD. Conclusion: Combining UTI and AZM can rapidly alleviate clinical symptoms and effectively control the progression of patients with SMPP. Therefore, this treatment approach deserves consideration for clinical promotion and utilization.

Etiology and clinical features of infection-associated plastic bronchitis in children.

OBJECTIVE: To investigate the etiological characteristics of plastic bronchitis (PB) caused by pulmonary infections in children and to identify any differences in the clinical features of PB cases caused by different pathogens. METHOD: We collected data on children diagnosed with PB and admitted to the Respiratory Department at Soochow University Children's Hospital between July 2021 and March 2023 utilizing electronic bronchoscopy. We analyzed clinical characteristics and the species of pathogens causing the illness in these children. RESULT: A total of 45 children were enrolled. The main clinical symptoms observed were cough (100%), fever (80%), shortness of breath (28.9%), and wheezing (20.0%). Pathogens were identified in 38 (84.4%) patients. Mycoplasma pneumoniae (MP) had the highest detection rate at 53.3%, followed by the Boca virus at 26.7%. MP-induced PB typically occurs in older children with an average age of 7.46 ± 2.36 years, with the main symptoms including high fever (85.7%) and local hyporespiration (42.9%). In contrast, Boca virus-induced PB tends to occur in younger children, with the main symptoms of moderate fever (54.5%), and wheezing (54.5%). The MP group exhibited a higher incidence of both internal and external pulmonary complications, including pleural effusion (42.9%), elevated aspartate aminotransferase (52.4%), lactic dehydrogenase (76.2%), and D-D dimer (90.5%). Conversely, the Boca virus group primarily showed pulmonary imaging of atelectasis (81.8%), with no pleural effusion. The average number of bronchoscopic interventions in the MP group was 2.24 ± 0.62, which was significantly higher than that required in the Boca virus group (1.55 ± 0.52). During the second bronchoscopy, 57.1% of children in the MP group still had visible mucus plugs, while none were observed in the Boca virus group. CONCLUSION: MP and Boca virus are the primary pathogens responsible for PB among children. The clinical manifestations of PB typically vary significantly based on the pathogen causing the condition.

Risk Prediction Model for Necrotizing Pneumonia in Children with Mycoplasma pneumoniae Pneumonia.

Objective: To analyze the predictive factors for necrotizing pneumonia (NP) in children with Mycoplasma pneumoniae pneumonia (MPP) and construct a prediction model. Methods: The clinical data with MPP at the Children's Hospital of Kunming Medical University from January 2014 to November 2022 were retrospectively analyzed. Eighty-four children with MPP who developed NP were divided into the necrotizing group, and 168 children who did not develop NP were divided into the non-necrotizing group by propensity-score matching. LASSO regression was used to select the optimal factors, and multivariate logistic regression analysis was used to establish a clinical prediction model. The receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the discrimination and calibration of the nomogram. Clinical decision curve analysis was used to evaluate the clinical predictive value. Results: LASSO regression analysis showed that bacterial co-infection, chest pain, LDH, CRP, duration of fever, and D-dimer were the influencing factors for NP in children with MPP (P < 0.05). The results of ROC analysis showed that the AUC of the prediction model established in this study for predicting necrotizing MPP was 0.870 (95% CI: 0.813-0.927, P < 0.001) in the training set and 0.843 (95% CI: 0.757-0.930, P < 0.001) in the validation set. The Bootstrap repeated sampling for 1000 times was used for internal validation, and the calibration curve showed that the model had good consistency. The Hosmer-Lemeshow test showed that the predicted probability of the model had a good fit with the actual probability in the training set and the validation set (P values of 0.366 and 0.667, respectively). The clinical decision curve showed that the model had good clinical application value. Conclusion: The prediction model based on bacterial co-infection, chest pain, LDH, CRP, fever duration, and D-dimer has a good predictive value for necrotizing MPP.

Reduced serum 25(OH)D is closely related to bronchial mucus plug formation in children with mycoplasma pneumonia: A prospective cohort study.

Background: The relationship between vitamin D nutritional status and the formation of bronchial mucus plugs (BMPs) is unclear. The aims of the current study were to investigate associations between serum 25(OH)D levels, serum inflammatory factors, and clinical characteristics in children with mycoplasma pneumonia (MPP), and to summarize the risk factors for BMPs in children with MPP. Methods: Clinical data from 175 children with MPP were collected and analyzed, the children were divided into a BMP group and a non-BMP group. Serum 25(OH)D levels, IL-8, and various inflammatory factors were compared in the two groups. Associations between 25(OH)D levels and IL-8, various inflammatory factors, and clinical characteristics were analyzed, and the diagnostic value of serum 25(OH)D levels was assessed. Results: Serum 25(OH)D level was significantly lower in the BMP group (p < 0.05). Serum IL-8 level, percentages of neutrophils, and some inflammatory factors were significantly higher in the BMP group (p < 0.05). Serum 25(OH)D level was negatively correlated with IL-8, neutrophil percentage, various inflammatory factors (all p < 0.05). It was also associated with lobular infection, pleural effusion, mechanical ventilation, and mycoplasma 2,063/2,064 mutation (all p < 0.05). In multivariate regression analysis 25(OH)D [odds ratio (OR) 0.98, 95% confidence interval (CI) 0.97-0.99, p = 0.003], IL-8 (OR 1.02, 95% CI 1.00-1.04, p = 0.002), polylobular infection (OR 1.75, 95% CI 1.17-2.64, p = 0.007), and MP DNA copies (OR 0.98, 95% CI 1.04-1.01, p = 0.022) were independent risk factors for BMPs, and the area under the curve value was 0.915 (95% CI 0.895-0.935). If the serum 25(OH)D level was <50 nmol/L, the respective percentages for sensitivity, specificity, positive predictive value, and negative predictive value were 97, 81, 78.9, and 97.6%. Conclusions: Vitamin D deficiency is common in children with MPP, and 25(OH)D levels are closely associated with inflammatory factors and disease severity in children. The serum 25 (OH) D level of MPP children with BMPs was lower than that of children without BMPs. Serum 25(OH)D can be used as a marker for the diagnosis of MPP in children with BMPs.

The role of serum inflammatory in mycoplasma pneumonia infection with respiratory asthma.

OBJECTIVE: With the growing frequency of Mycoplasma pneumoniae infections linked to respiratory asthma (MP-RA), particularly in children, the quest for novel diagnostic molecular markers has become critical. We examined the link between serum immunoglobulin, inflammatory variables, vitamin A, and vitamin D levels in MP-RA patients and then found markedly diagnostic indicators. METHODS: From January 2015 to March 2020, our hospital screened 55 cases of healthy control children (HC), 53 instances of mycoplasma pneumonia infection complicated with respiratory asthma (MP-RA), and 58 cases of non-respiratory asthma children for pneumonia mycoplasma infection (MP). Serum immunoglobulins, inflammatory markers, vitamin D, and vitamin A levels were analyzed, and a predictive model including the feature chosen in the least absolute shrinkage and selection operator regression model was developed. RESULTS: Serum TNF- and IL-1b levels were greater in MP-RA children than in MP children, but 25(OH)D, IgG, and IgA levels were lower. Our findings verified the link between IgA, TNF-a, 25(OH)D, and vitamin A with MP-RA. In addition, TNF-a, IL-1b, 25(OH)D (Vit-D), IgG, and IgA were the predictors in the prediction nomogram, showing the combined influence of serum inflammation in MP-RA. C-index of 0.985 (95% CI: -1.25 to 1.68) shows high scaling ability and the model exhibits good discriminative capacity. With range validation, the high C-index value of 0.96 is still possible. CONCLUSION: TNF-a, IL-1b, 25(OH)D (Vit-D), IgG, and IgA were considered as predictors in children with MP-RA was investigated in this research.

Apigenin suppresses mycoplasma-induced alveolar macrophages necroptosis via enhancing the methylation of TNF-α promoter by PPARγ-Uhrf1 axis.

BACKGROUND: Mycoplasma-associated pneumonia is characterized by severe lung inflammation and immunological dysfunction. However, current anti-mycoplasma agents used in clinical practice do not prevent dysfunction of alveolar macrophages caused by the high level of the cytokine tumor necrosis factor-α (TNF-α) after mycoplasma infection. Apigenin inhibits the production of TNF-α in variet inflammation associated disease. PURPOSE: This study aimed to investigate apigenin's effect on mycoplasma-induced alveolar immune cell injury and the mechanism by which it inhibits TNF-α transcription. METHODS: In this study, we performed a mouse model of Mycoplasma hyopneumoniae infection to evaluate the effect of apigenin on reducing mycoplasma-induced alveolar immune cell injury. Furthermore, we carried out transcriptome analysis, RNA interference assay, methylated DNA bisulfite sequencing assay, and chromatin immunoprecipitation assay to explore the mechanism of action for apigenin in reducing TNF-α. RESULTS: We discovered that M. hyopneumoniae infection-induced necroptosis in alveolar macrophages MH-S cells and primary mouse alveolar macrophages, which was activated by TNF-α autocrine. Apigenin inhibited M. hyopneumoniae-induced elevation of TNF-α and necroptosis in alveolar macrophages. Apigenin inhibited TNF-a mRNA production via increasing ubiquitin-like with PHD and RING finger domains 1 (Uhrf1)-dependent DNA methylation of the TNF-a promotor. Finally, we demonstrated that apigenin regulated Uhrf1 transcription via peroxisome proliferator activated receptor gamma (PPARγ) activation, which acts as a transcription factor binding to the Uhrf1 promoter and protected infected mice's lungs, and promoted alveolar macrophage survival. CONCLUTSION: This study identified a novel mechanism of action for apigenin in reducing alveolar macrophage necroptosis via the PPARγ/ Uhrf1/TNF-α pathway, which may have implications for the treatment of Mycoplasma pneumonia.

Prognosis and correlation analysis of serum SAA, PCT and SF levels in children with severe mycoplasma pneumonia / 公共卫生与预防医学

Objective To analyze the prognosis of children with severe mycoplasma pneumonia (MPP) and its correlation with serum SAA, PCT and SF levels, so as to provide a basis for evaluating the prognosis of children with MPP. Methods A total of 273 children with MPP admitted to our hospital from January 2020 to December 2020 were divided into mild MPP children (n=187) and severe MPP children (n=86) according to the severity of their disease. According to the prognosis, children with severe MPP were divided into survival group (n=65) and death group (n=21). Serum SAA, PCT and SF levels were determined. Pearson correlation analysis was used to analyze the correlation between serum SAA, PCT and SF levels and APACHE ⅱ score. ROC curve was used to analyze the predictive value of serum SAA, PCT and SF levels for poor prognosis of children with severe MPP. Results The levels of serum SAA, PCT and SF and APACHE II score in children with severe MPP were significantly higher than those in children with mild MPP (P<0.05). Serum SAA, PCT and SF levels and APACHE II score in death group were significantly higher than those in survival group (P<0.05). Pearson correlation analysis showed that APACHE II score was positively correlated with serum SAA, PCT and SF levels (r =0.474,0.519,0.446,P<0.05). The AUC, sensitivity and specificity of combined ROC curve analysis to predict the prognosis of severe MPP were 0.871, 85.9% and 93.6% respectively, which were higher than those of SAA, PCT and SF alone. Conclusion SAA, PCT and SF are closely related to the prognosis of severe MPP, and can be used as potential markers to predict poor prognosis of severe MPP children.

Maternal Exposure to Mycoplasma Pneumonia and Amniotic Constriction Band: A Case Report of Probable Novel Etiology.

Amniotic constriction band (ACB) is an uncommon clinical concept with different presentations specific to each patient with clinical symptoms may include ring constrictions, digital defects, natural limb amputations, and visceral defects. The etiology of this defect is not fully understood. We present a full-term newborn boy who was born by vaginal delivery to a healthy mother. At birth, amniotic bands encircled and constricted his upper and lower limbs. At two and six months of gestation, the mother gave a unique obstetric history of recurrent exposure to her infected daughter, which was diagnosed later as a case of atypical M. pneumoniae. This raises suspicion that M. pnemoniae may play a critical role in the pathogenesis of ACB and the hypothesis related to its origin. The inquiry in our case is whether M. pneumoniae might have been a non-aberrant teratogen and caused subclinical chorioamnionitis that leads to early rupture of amniotic membranes and result in the proposed defects. As far as we know, this is the first case reported in the literature that combines gestational exposure to M. pneumoniae and postpartum isolated amniotic constrictions and minor digital defects in Saudi Arabia newborns. In addition, we discussed the possible underlying causes and reviewed the published literature on this defect.

Lymphoplasmacytic Lymphoma/Waldenstrom Macroglobulinemia Masquerading as IgM Warm Antibody Autoimmune Hemolytic Anemia in Association With Mycoplasma pneumoniae Infection: A Case Report.

Warm antibody autoimmune hemolytic anemia (AIHA) is mostly of IgG subtype. IgM subtype is extremely rare and has not been reported in association with lymphoplasmacytic lymphoma (LPL)/Waldenström macroglobulinemia (WM). We are reporting the case of a 75-year-old female patient who presented with severe hemolytic anemia and Mycoplasma pneumoniae pneumonia (MPP). Cold agglutinin and serum protein electrophoresis (SPEP) were negative but immunofixation was positive for IgM. Ultimately, hemolytic anemia was labeled warm antibody AIHA in association with MPP. She presented again one year later with more severe hemolytic anemia. Persistently elevated IgM was seen in immunofixation and triggered bone marrow biopsy that confirmed LPL/WM. This case highlights the clinical pearl that warm antibody AIHA in association with MPP is a rare entity and more intensive investigation to rule out other etiologies is mandated. Also, this case is rare as it is of IgM subtype warm AIHA and observed in the context of LPL/WM.

Visual detection of Mycoplasma pneumoniae by the recombinase polymerase amplification assay coupled with lateral flow dipstick.

Mycoplasma pneumoniae (Mp) is a common cause of respiratory infections in school-age children. In the present study, a recombinase polymerase amplification (RPA) assay combined with lateral flow dipstick (LFD) was developed for diagnosis of Mp. Specific primers and a probe were designed for the Mp p1 gene. The optimal reaction conditions of the RPA-LFD assay were 37 °C and 25 min. The minimal detection limit of the RPA assay was 10 DNA molecules. The RPA method had no cross-reaction with the other 14 common pathogens tested. The practicability of the assay for detecting Mp in clinical samples from the patients suspected to be Mp infection was also determined. The nucleic acids of the clinical samples were extracted by the DNA Rapid extraction reagent which took about 10 min. The clinical specimens were detected by the RPA method, and the result showed high agreement with that of the qPCR commercial kit. The RPA-LFD method with high sensitivity and specificity is easy to perform and is an alternative method for field detection in resources-limited settings.

Clinical characteristics of patients with Mycoplasma pneumoniae infection.

OBJECTIVE: To describe the characteristics of patients diagnosed with Mycoplasma pneumoniae infection. METHODS: A retrospective study of clinical and epidemiological characteristics of acute infections by M. pneumoniae confirmed by PCR was carried out in the Navarra Health Service (Spain) in 2014-2018. RESULTS: M. pneumoniae infection was confirmed in 9.5% of analyzed patients. Among 123 confirmed cases, 65% were 5-14 years old, 21.1% <5 years old, and 13.8% were ≥14 years old. Pneumonia was radiologically confirmed in 83.7% of cases, and 22.0% presented extra-respiratory manifestations. A total of 44.7% of cases required hospitalization. Bilateral pneumonia, asthmatic crisis and extra-respiratory manifestations were associated to higher risk of hospitalization (81.3, 72.2 and 66.7%, respectively). Microbiological targeted treatment was monotherapy with macrolides in 60.2% of cases and combined with other antibiotics in 13.0%. CONCLUSION: M. pneumoniae was the cause of acute respiratory infection affecting mainly to children younger than 14 years old and frequently required hospitalization.