Macrolide-Resistant Mycoplasma pneumoniae Infections in Children, Ohio, USA

Treatment modalities for fever duration in children with Mycoplasma pneumoniae pneumonia

Mycoplasma pneumoniae is the leading cause of community-acquired pneumonia in children. With increasing macrolide resistance, the use of second-line antibiotics such as tetracyclines and quinolones is also increasing. Clinical data were collected from 13 institutions between September 2023 and February 2024. MPP was defined as the detection of M. pneumoniae via polymerase chain reaction or serological tests and radiologic evidence of pneumonic infiltration. Among the 389 children with MPP included in the analysis, 89.1% were macrolide resistant (MR). The treatment groups were as follows: spontaneous resolution (SR, 21.9%), macrolide alone (ML, 18.0%), macrolide with other treatments (ML-O, 38.0%), and second-line antibiotics and/or steroids (2nd-A/S, 22.1%). The median fever duration was 5 days for the SR group, 7 days for both the ML and 2nd-A/S groups, and 8 days for the ML-O group. The ML-O group had significantly greater hospitalization rates (93.9% vs. 81.4-84.7%, P = 0.023) and longer hospital stays (5.0 days vs. 3.0-4.0 days, P < 0.001). The median times to defervescence from the initiation of macrolide and second-line treatments were 2-3 days and 0-2 days, respectively. In conclusion, despite high MR rates, macrolide monotherapy remains effective in many patients, even those with macrolide-resistant M. pneumoniae.

Clinical characteristics and associated factors of macrolide-resistant mycoplasma pneumoniae pneumonia in children: a systematic review and meta-analysis

In recent years, the incidence of macrolide-resistant Mycoplasma pneumoniae (MRMP) pneumonia has markedly increased across East Asia, especially in China, Japan, and South Korea, presenting considerable challenges for clinical management. We systematically reviewed and conducted a meta-analysis on the resistance rate, clinical characteristics, and associated factors of MRMP, thereby establishing a foundation for early clinical identification and optimization of treatment strategies. In accordance with the PRISMA 2020 reporting guidelines, six databases including PubMed, Embase, Web of Science, CNKI, VIP, and Wanfang Data were systematically searched for relevant literature up to October 31, 2024. Studies explicitly reporting the clinical characteristics of both MRMP and macrolide-sensitive Mycoplasma pneumoniae (MSMP) pneumonia patients were included, with the population restricted to children. Pooled odds ratio (OR) and mean difference (MD), along with 95% confidence intervals, were calculated using inverse-variance weighting. A significance threshold was set at p < 0.05, and meta-analysis was performed using software such as RevMan, Stata, and R Studio. A total of 65 studies encompassing 20,141 patients were included in this analysis. The meta-analysis revealed that MRMP showed high resistance in East Asia compared to lower resistance in other regions. The overall resistance rate was 61% (95% CI: 54%, 68%), exhibiting notable regional variation. Elevated resistance rates were noted in East Asian countries, specifically China, Japan, and South Korea, reported at 68% (95% CI: 63%, 73%), 61% (95% CI: 43%, 80%), and 63% (95% CI: 42%, 85%), respectively. MRMP resistance was significantly associated with prolonged fever duration (MD: 1.97, 95% CI: 1.10, 2.84), extended hospitalization (MD: 1.96, 95% CI: 1.39, 2.54), elevated log MP-DNA levels (MD: 2.79, 95% CI: 1.54, 4.04), increased proportions of severe (OR: 2.45, 95% CI: 1.75, 3.44) cases and refractory (OR: 3.25, 95% CI: 1.47, 7.17) cases, and the occurrence of complications, particularly intrapulmonary manifestations including pulmonary consolidations (OR: 1.43, 95% CI: 1.14, 1.78), pleural effusions (OR: 2.11, 95% CI: 1.28, 3.49), lobar lesions (OR: 2.03, 95% CI: 1.03, 4.00), mucus plugs (OR: 4.63, 95% CI: 1.66, 12.94), and necrotizing pneumonia (OR: 2.49, 95% CI: 1.19, 5.24), alongside extrapulmonary involvement (OR: 3.08, 95% CI: 2.49, 3.82). No significant differences were observed in peak body temperature (MD: 0.05, 95% CI: -0.11, 0.20) or inflammatory markers including white blood cell count (WBC, MD: 0.28, 95% CI: -0.38, 0.94), C-reactive protein (CRP, MD: 0.71, 95% CI: -2.16, 3.58), Procalcitonin (PCT, MD: -0.11, 95% CI: -0.27, 0.05) and lactate dehydrogenase (LDH, MD: 3.80, 95% CI: -22.92, 30.52). The high resistance rate may be associated with environmental pressure stemming from the widespread use of macrolide antibiotics and increased genetic mutations due to the extensive spread of MP. The observed increase in severe cases, refractory cases, and complications associated with MRMP may be attributed to prolonged colonization resulting from ineffective anti-Mycoplasma pneumoniae treatment, rather than to enhanced virulence or a more severe cytokine storm. PROSPERO registration number CRD42024550871.

Macrolide-Resistant Mycoplasma pneumoniae in Children: Emphasis on the United States

Several studies regarding infections caused by macrolide-resistant Mycoplasma pneumoniae have been reported in the last years in the United States, where the prevalence is approximately 10% but may range from 3% to even 80%. Macrolide-resistant M. pneumoniae may be associated with prolonged fever, hospital stay, and complications. Suspicion should be raised by non-response to macrolides, and detection can be achieved through routine reflexive testing of M. pneumoniae-positive specimens with a polymerase-chain reaction assay that rapidly predicts macrolide resistance. After timely initiation of an alternative antibiotic, prompt resolution of the disease is likely in most cases. This review summarizes current US data, offers some suggestions, and identifies knowledge gaps on this infection.

Macrolide-Resistant Mycoplasma pneumoniae Infections among Children after COVID-19 Pandemic, Ohio, USA

Mycoplasma pneumoniae infections decreased in Ohio, USA, during the COVID-19 pandemic but reemerged in 2023; >2,000 cases were reported during September 2023--September 2024. Of 995 M. pneumoniae-positive samples, 24 (2.4%) had mutations for macrolide-resistant M. pneumoniae (MRMp). MRMp rates are low but increasing. MRMp surveillance is crucial for monitoring antimicrobial resistance.

Clinical Characteristics and Treatment Outcomes of Pediatric Drug-Resistant Mycoplasma pneumoniae Pneumonia in the Post-COVID-19 Era

Background

Mycoplasma pneumoniae pneumonia (MPP) is a prevalent disease among children. Typically, macrolides are the first-line treatment for MPP in China. However, the number of cases resistant to macrolides has been rising, especially after the outbreak of the COVID-19 pandemic, which has further complicated the clinical management of macrolide-unresponsive Mycoplasma pneumoniae pneumonia (MUMPP) in children.

Objective

This study examined the clinical characteristics of MUMPP and the effects of various treatments on children with MUMPP during March 2023 to February 2024 in southern China.

Methods

We conducted a retrospective case-control study at a university-affiliated hospital in southern China. Patients were categorized based on their response to macrolide treatment into two groups: MUMPP and control group. The study included 549 pediatric patients. Of these, 297 were in the MUMPP group and 252 were in the control group. This categorization allowed us to compare clinical characteristics and laboratory indicators between the groups. The MUMPP group received one of the three treatments: combined antibiotics, additional steroids, or a switch to doxycycline. Subsequently, we analyzed differences in clinical outcomes, which included hospital stay, hospital cost, and recovery time.

Results

No significant differences were found in gender or pre-admission disease duration between the MUMPP and control group (P>0.05). However, subjects in MUMPP group was older, had longer fever durations, extended hospital stays, higher medical costs, and elevated levels of C-reactive protein, lactate dehydrogenase, IL-6, and γ-IFN. All of which showed statistically significant differences (P<0.05). Within the MUMPP group, patients switched to doxycycline had the shortest hospital stay and recovery time, significantly differing from those in other treatment groups (P<0.05).

Conclusion

Children in the MUMPP group exhibited higher inflammatory indicators than the control group. The early adaptation of treatment strategies, particularly the switch to doxycycline, is associated with improved clinical outcomes.

Macrolide-Resistant Mycoplasma pneumoniae, North Dakota 2024

A cluster of macrolide-resistant Mycoplasma pneumoniae -causing community-acquired pneumonia was observed in children in North Dakota in 2024. Suspicion was raised by non-response to macrolides, with confirmation via a polymerase-chain reaction assay. Prompt improvement occurred after the initiation of alternative antibiotics.

Clinical Characteristics and Laboratory Diagnoses of Pediatric Patients Hospitalized During an Outbreak of Mycoplasma pneumoniae

This study prospectively collected the clinical data, information on respiratory pathogens, and laboratory findings of children with Mycoplasma pneumoniae (M. pneumonia) infection who were hospitalized at the First Affiliated Hospital of Anhui Medical University during the M. pneumoniae outbreak in Hefei City, Anhui Province, China, between October 2023 and December 2023. We analyzed the prevalence of M. pneumoniae infection in hospitalized children during the M. pneumoniae outbreak, discrepancies in the detection of M. pneumoniae by multiplex polymerase chain reaction (PCR) and serological methods, and the differences in clinical characteristics and laboratory results of patients with co-infections of M. pneumoniae and other pathogens with the aim of providing a reference for disease assessment and clinical treatment of M. pneumoniae. A total of 270 children, 146 males and 124 females, were enrolled in the study after screening with the inclusion criteria. The most common co-infections were adenovirus (ADV) (48 cases) and influenza A virus (FLU A) (30 cases). The prevalence of infections was higher in children under the age of 7 years (54.1%). In addition, 167 of the PCR-positive patients were infected with macrolide-resistant Mycoplasma pneumoniae (MRMP), suggesting that MRMP infections are common in hospitalized children. Levels of procalcitonin (PCT) (OR 15.765 [95% CI, 1.651-150.533], p < 0.017) and lactate dehydrogenase (LDH) (OR 1.006 [95% CI, 1.003-1.009], p < 0.001) were independently predictive of co-infections in patients infected with M. pneumoniae.

Impact of the COVID-19 pandemic on epidemiological and clinical characteristics of Mycoplasma pneumoniae pneumonia in children: a multicenter study from Hubei, China

Aims

To investigate the epidemiological and clinical characteristics of children with Mycoplasma pneumoniae pneumonia (MPP) in Hubei, China.

Methods

We retrospectively analyzed inpatients with MPP from 20 hospitals in Hubei, China from January 2021 to December 2022. The co-detected pathogens of Mycoplasma pneumoniae (M. pneumoniae) were investigated using targeted next-generation sequencing (tNGS), and 23S rRNA gene mutations were analyzed to assess the macrolide resistance.

Results

M. pneumoniae infected 20.7% of patients with CAP, with cough (96.59%) and fever (80.28%) being the most prevalent symptoms. The infection rates in children younger than 1, 1-2, 3-6, 7-12, and older than 12 years were 6.17%, 19.98%, 26.97%, 43.93%, and 2.95%, respectively. Among 1,349 patients undergoing tNGS, the overall co-detection rate was 59.45%, with Streptococcus pneumoniae (29.30%), Haemophilus influenzae (23.57%), and Human rhinovirus (17.21%) being the most commonly co-detected pathogens. In 635 patients undergoing the 23S rRNA gene mutation test, 86.30% exhibited positive mutations (A2063G, 98.00%; A2064G, 1.50%; A2067G, 0.50%). Despite a significant age difference (P = 0.037) between macrolide-resistant M. pneumoniae and macrolide-sensitive M. pneumoniae groups, there were no significant differences in symptoms, lab data, or disease severity.

Conclusions

In Hubei Province, the prevalence of exhibited consistent changes during the COVID-19 pandemic. MPP was prevalent year-round, particularly in summer and autumn, with school-age children being more susceptible. Co-detections of viruses and bacteria were frequent in MPP cases, and macrolide resistance exceeded 85%. Ongoing surveillance of M. pneumoniae in children is crucial for understanding the healthcare impact of MPP.

Severe Mycoplasma pneumoniae infection in a young child: An emerging increase in incidence?

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Expert consensus on the diagnosis and treatment of macrolide-resistant Mycoplasma pneumoniae pneumonia in children

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae) is a significant contributor to community-acquired pneumonia among children. Since 1968, when a strain of M. pneumoniae resistant to macrolide antibiotics was initially reported in Japan, macrolide-resistant M. pneumoniae (MRMP) has been documented in many countries worldwide, with varying incidence rates. MRMP infections lead to a poor response to macrolide antibiotics, frequently resulting in prolonged fever, extended antibiotic treatment, increased hospitalization, intensive care unit admissions, and a significantly higher proportion of patients receiving glucocorticoids or second-line antibiotics. Since 2000, the global incidence of MRMP has gradually increased, especially in East Asia, which has posed a serious challenge to the treatment of M. pneumoniae infections in children and attracted widespread attention from pediatricians. However, there is still no global consensus on the diagnosis and treatment of MRMP in children.

METHODS

We organized 29 Chinese experts majoring in pediatric pulmonology and epidemiology to write the world's first consensus on the diagnosis and treatment of pediatric MRMP pneumonia, based on evidence collection. The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, CNKI, Medline, and the Cochrane Library. We used variations in terms for "macrolide-resistant", "Mycoplasma pneumoniae", "MP", "M. pneumoniae", "pneumonia", "MRMP", "lower respiratory tract infection", "Mycoplasma pneumoniae infection", "children", and "pediatric".

RESULTS

Epidemiology, pathogenesis, clinical manifestations, early identification, laboratory examination, principles of antibiotic use, application of glucocorticoids and intravenous immunoglobulin, and precautions for bronchoscopy are highlighted. Early and rapid identification of gene mutations associated with MRMP is now available by polymerase chain reaction and fluorescent probe techniques in respiratory specimens. Although the resistance rate to macrolide remains high, it is fortunate that M. pneumoniae still maintains good in vitro sensitivity to second-line antibiotics such as tetracyclines and quinolones, making them an effective treatment option for patients with initial treatment failure caused by macrolide antibiotics.

CONCLUSIONS

This consensus, based on international and national scientific evidence, provides scientific guidance for the diagnosis and treatment of MRMP in children. Further studies on tetracycline and quinolone drugs in children are urgently needed to evaluate their effects on the growth and development. Additionally, developing an antibiotic rotation treatment strategy is necessary to reduce the prevalence of MRMP strains.

Clinical Manifestations, Macrolide Resistance, and Treatment Utilization Trends of Mycoplasma pneumoniae Pneumonia in Children and Adolescents in South Korea

A resurgence of Mycoplasma pneumoniae (MP)-the leading cause of community-acquired bacterial pneumonia, particularly in children-occurred following the COVID-19 pandemic. We aimed to investigate the clinical manifestations, macrolide resistance patterns, and therapeutic approaches related to the MP pneumonia epidemic. Children and adolescents diagnosed with MP pneumonia in September-December 2023 were screened. Clinical data were retrospectively collected from 13 major hospitals using concordant microbiological criteria, including either a positive PCR result or four-fold increase in serological markers. Demographic characteristics, treatment modalities, and clinical outcomes were analyzed. Of the 474 screened patients, 374 (median age: 7.7 [IQR, 5.4-9.6] years; hospitalization rate: 88.6%) met the microbiological confirmation criteria. Most patients experienced fever (98.9%), and lobular/lobar consolidation (59.1%) was the dominant radiological finding. The macrolide resistance rate remained high at 87.0%; corticosteroids were widely used (55.6%) alongside macrolides, despite resistance. Patients with consolidation had prolonged fever (median 8 vs. 7 days, p = 0.020) and higher hospitalization rates (92.3% vs. 83.0%, p = 0.008). Macrolide resistance did not significantly influence radiological outcomes. This study highlights the ongoing challenge of macrolide resistance in MP pneumonia and need for tailored therapeutic approaches. Despite high resistance, macrolides remain commonly prescribed, often concurrently with corticosteroids.

Comparative genomic sequencing to characterize Mycoplasma pneumoniae genome, typing, and drug resistance

To analyze the characteristics of Mycoplasma pneumoniae as well as macrolide antibiotic resistance through whole-genome sequencing and comparative genomics. Thirteen clinical strains isolated from 2003 to 2019 were selected, 10 of which were resistant to erythromycin (MIC >64 µg/mL), including 8 P1-type I and 2 P1-type II. Three were sensitive (<1 µg/mL) and P1-type II. One resistant strain had an A→G point mutation at position 2064 in region V of the 23S rRNA, the others had it at position 2063, while the three sensitive strains had no mutation here. Genome assembly and comparative genome analysis revealed a high level of genome consistency within the P1 type, and the primary differences in genome sequences concentrated in the region encoding the P1 protein. In P1-type II strains, three specific gene mutations were identified: C162A and A430G in L4 gene and T1112G mutation in the CARDS gene. Clinical information showed seven cases were diagnosed with severe pneumonia, all of which were infected with drug-resistant strains. Notably, BS610A4 and CYM219A1 exhibited a gene multi-copy phenomenon and shared a conserved functional domain with the DUF31 protein family. Clinically, the patients had severe refractory pneumonia, with pleural effusion, necessitating treatment with glucocorticoids and bronchoalveolar lavage. The primary variations between strains occur among different P1-types, while there is a high level of genomic consistency within P1-types. Three mutation loci associated with specific types were identified, and no specific genetic alterations directly related to clinical presentation were observed.IMPORTANCEMycoplasma pneumoniae is an important pathogen of community-acquired pneumonia, and macrolide resistance brings difficulties to clinical treatment. We analyzed the characteristics of M. pneumoniae as well as macrolide antibiotic resistance through whole-genome sequencing and comparative genomics. The work addressed primary variations between strains that occur among different P1-types, while there is a high level of genomic consistency within P1-types. In P1-type II strains, three specific gene mutations were identified: C162A and A430G in L4 gene and T1112G mutation in the CARDS gene. All the strains isolated from severe pneumonia cases were drug-resistant, two of which exhibited a gene multi-copy phenomenon, sharing a conserved functional domain with the DUF31 protein family. Three mutation loci associated with specific types were identified, and no specific genetic alterations directly related to clinical presentation were observed.

Effectiveness and safety of tetracyclines and quinolones in people with Mycoplasma pneumonia: a systematic review and network meta-analysis

Background

The escalating resistance of Mycoplasma pneumoniae to macrolides has become a significant global health concern, particularly in low-income and middle-income countries (LMICs). Although tetracyclines and quinolones have been proposed as alternative therapeutic options, concerns regarding age-specific safety issues and the lack of consensus in recommendations across various national guidelines prevail. Thus, the primary objective of this study is to ascertain the most efficacious interventions for second-line treatment of M. pneumoniae infection while considering the age-specific safety issues associated with these interventions.

Methods

In this systematic review and network meta-analysis we searched PubMed, Embase, CNKI, and WanFang Data, from inception up to November 11th, 2023. Studies of quinolones or tetracyclines for the treatment of people with M. pneumoniae infection were collected and screened by reading published reports, with any type of study included, and no individual patient-level data requested. A systematic review and direct meta-analysis compared the efficacy of tetracyclines and quinolones regarding time to defervescence (TTD) and the rates of fever disappearance within 24 h and 48 h of antibiotic administration, for managing M. pneumoniae infection. Bayesian network meta-analysis (NMA) was employed to indirectly assess the relative effectiveness of different interventions in people with M. pneumoniae infection and the safety profile of medication in paediatric patients. This study is registered with PROSPERO, CRD42023478383.

Findings

The systematic review and direct meta-analysis included a total of 4 articles involving 246 patients, while the NMA encompassed 85 articles involving a substantial cohort of 7095 patients. The NMA measured the effectiveness across all ages and included 7043 patients, with a mean age of 37.80 ± 3.91 years. Of the 85 included studies, 14 (16.5%) were at low risk of bias, 71 (83.5%) were at moderate risk, and no studies were rated as having a high risk of bias. In the direct meta-analysis, no statistically significant differences were found between tetracyclines and quinolones concerning TTD (mean difference: -0.40, 95% CI: -1.43 to 0.63; I2 = 0%), fever disappearance rate within 24 h of antibiotic administration (OR: 0.37, 95% CI: 0.08-1.79; I2 = 58%), and fever disappearance rate within 48 h of antibiotic administration (OR: 1.10, 95% CI: 0.30-3.98; I2 = 59%). However, the comprehensive NMA analysis of clinical response (in 70 studies; n = 6143 patients), shortening of TTD (in 52 studies; n = 4363 patients), shortening length of cough relief or disappearance (in 39 studies; n = 3235 patients), fever disappearance rate at 48 h (in four studies; n = 418 patients) revealed that minocycline exhibited the most favourable outcomes across these various parameters, and the analysis of fever disappearance rate at 24 h (in three studies; n = 145 patients) revealed that levofloxacin may be the most effective, as indicated by the rank probabilities and surface under the cumulative ranking area (SUCRA) value. Moxifloxacin ranked second in clinical response and in shortening the length of cough relief or disappearance, and third in shortening TTD. Notably, when evaluating the occurrence of adverse reactions in paediatric patients (in four studies; n = 239 children), levofloxacin was associated with the highest SUCRA value rankings for the rate of adverse events.

Interpretation

Our findings suggest that tetracyclines and quinolones may be equally effective. Based on the age of participants in the included studies, minocycline may be the most effective intervention for children over eight years of age when all preventive measures are considered, whereas moxifloxacin may benefit people under eight years of age. However, these results should be interpreted with caution, given the limited number of studies and patients included, and the heterogeneity between included studies. Based on a limited number of studies in children, levofloxacin is likely to have one of the highest rates of adverse reactions. The majority of the studies included in the NMA were from the Asian region, and more randomised controlled trials comparing different therapeutic strategies in patients with M. pneumoniae are warranted. This comparative study provides clinical pharmacists and clinicians with important information to enable them to make informed decisions about treatment options, considering drug efficacy and safety.

Funding

The Natural Science Foundation of Fujian Province, China.

Observational retrospective clinical study on clinical features of macrolide-resistant Mycoplasma pneumoniae pneumonia in Chinese pediatric cases

This study aimed to investigate differences in clinical characteristics and laboratory findings between children infected with Macrolide-Sensitive Mycoplasma pneumoniae (MSMP) and Macrolide-Resistant Mycoplasma pneumoniae (MRMP). Additionally, the research sought to identify laboratory markers for rapidly distinguishing refractory Mycoplasma pneumoniae pneumonia (RMPP) from ordinary Mycoplasma pneumoniae pneumonia (OMPP). In total, 265 Mycoplasma pneumoniae (MP) patients were included, with MRMP identified by specific point mutations in domain V of the 23S rRNA gene. A retrospective analysis compared the clinical courses and laboratory data, revealing that MRMP patients experienced prolonged febrile days (P = 0.004), elevated CRP levels (P < 0.001), and higher MP DNA loads than MSMP patients (P = 0.037). Based on clinical symptoms, MRMP was divided into RMPP (n = 56) and OMPP (n = 70), with RMPP demonstrating significantly increased IL-18, community-acquired respiratory distress syndrome (CARDS) toxins in nasopharyngeal aspirate, and serum CRP levels (P < 0.001; P = 0.006; P < 0.001). In conclusion, timely recognition of RMPP is crucial for enhancing prognosis. The identification of MRMP, coupled with proinflammatory cytokines such as IL-18, CARDS toxins, and CRP, emerges as promising markers with the potential to contribute significantly to diagnostic accuracy and prognosis assessment.

Characteristics of the Mycoplasma pneumoniae Epidemic from 2019 to 2020 in Korea: Macrolide Resistance and Co-Infection Trends

Mycoplasma pneumoniae, a major etiological agent of community-acquired pneumonia, exhibits distinct cyclic epidemic patterns recurring every three to five years. Several cases of co-infection with severe acute respiratory syndrome coronavirus 2 have been reported globally, resulting in unfavorable clinical manifestations. This study investigated the epidemiological features of the recent M. pneumoniae outbreak (May 2019-April 2020) using retrospective data from the last five years. Molecular test data for macrolide resistance and co-infection were obtained from the Seegene Medical Foundation. National medical expenditure and hospitalization rates were analyzed using data from The Health Insurance Review and Assessment Service of Korea. The macrolide resistance rate was 69.67%, peaking at 71.30% during the epidemic period, which was considerably higher than the 60.89% rate during non-epidemic periods. The co-infection rate with other respiratory pathogens was 88.49%; macrolide-resistant M. pneumoniae strains showed a 2.33% higher co-infection rate than the susceptible strains. The epidemic period had 15.43% higher hospitalization and 78.27% higher medical budget expenditure per patient than non-epidemic periods. The increased rates of macrolide resistance and co-infection observed in macrolide-resistant M. pneumoniae during the epidemic period highlight the importance of monitoring future outbreaks, especially considering macrolide resistance and the risk of co-infection with other pathogens.

Investigation of oral macrolide prescriptions in Japan using a retrospective claims database, 2013-2018

Macrolide usage in Japan exceeds that in Europe and the United States. Investigating the actual conditions in which macrolides are used is important for identifying further interventions for appropriate antimicrobial use; however, this situation has not been evaluated in Japan. Therefore, we aimed to clarify the number of macrolide prescriptions and their changes before and after implementation of the Antimicrobial Resistance (AMR) Action Plan. In addition, we also investigated the names of diseases for which macrolides have been prescribed and the number of days of prescription. A retrospective observational study was conducted using JMDC claims data from January 2013 to December 2018. The proportion of all oral antimicrobials and macrolides used during this period and the diseases for which macrolides were used in the 3 years before and after the AMR Action Plan were determined separately for acute (< 14 prescription days) and chronic (> 14 prescription days) diseases. The number of prescriptions for macrolides constituted approximately 30% of those for all oral antimicrobials; of these, clarithromycin accounted for approximately 60%. Most prescriptions for acute diseases were for common cold, whereas allergic and dermatological diseases were included among chronic diseases. The names of these illnesses did not change before and after the AMR Action Plan. Overall, these results indicate that appropriate macrolide use involves a review of their use for common cold along with appropriate evaluation of their long-term use for skin and allergic diseases. They also indicate the need for further fact-finding studies and ongoing AMR measures.

Erythromycin Restores Osteoblast Differentiation and Osteogenesis Suppressed by Porphyromonas gingivalis Lipopolysaccharide

The macrolide erythromycin (ERM) inhibits excessive neutrophil accumulation and bone resorption in inflammatory tissues. We previously reported that the expression of developmental endothelial locus-1 (DEL-1), an endogenous anti-inflammatory factor induced by ERM, is involved in ERM action. Furthermore, DEL-1 is involved in the induction of bone regeneration. Therefore, in this study, we investigated whether ERM exerts an osteoblastogenic effect by upregulating DEL-1 under inflammatory conditions. We performed in vitro cell-based mechanistic analyses and used a model of Porphyromonas gingivalis lipopolysaccharide (LPS)-induced periodontitis to evaluate how ERM restores osteoblast activity. In vitro, P. gingivalis LPS stimulation suppressed osteoblast differentiation and bone formation. However, ERM treatment combined with P. gingivalis LPS stimulation upregulated osteoblast differentiation-related factors and Del1, indicating that osteoblast differentiation was restored. Alveolar bone resorption and gene expression were evaluated in a periodontitis model, and the results confirmed that ERM treatment increased DEL-1 expression and suppressed bone loss by increasing the expression of osteoblast-associated factors. In conclusion, ERM restores bone metabolism homeostasis in inflammatory environments possibly via the induction of DEL-1.

Recent Trend of Antimicrobial Susceptibility among Mycoplasma pneumoniae Isolated from Japanese Children

Macrolide-resistant Mycoplasma pneumoniae (MRMP) infections have become increasingly prevalent, especially in East Asia. Whereas MRMP strains have point mutations that are implicated in conferring resistance, monitoring the antibiotic susceptibility of M. pneumoniae and identifying mutations in the resistant strains is crucial for effective disease management. Therefore, we investigated antimicrobial susceptibilities among M. pneumoniae isolates obtained from Japanese children since 2011. To establish the current susceptibility trend, we analyzed the minimum inhibitory concentrations (MICs) of M. pneumoniae in recent years (2017−2020) in comparison with past data. Our observation of 122 M. pneumoniae strains suggested that 76 were macrolide-susceptible M. pneumoniae (MSMP) and 46 were macrolide-resistant. The MIC ranges (µg/mL) of clarithromycin (CAM), azithromycin (AZM), tosufloxacin (TFLX), and minocycline (MINO) to all M. pneumoniae isolates were 0.001−>128, 0.00012−>128, 0.25−0.5, and 0.125−4 µg/mL, respectively. None of the strains was resistant to TFLX or MINO. The MIC distributions of CAM and AZM to MSMP and MINO to all M. pneumoniae isolates were significantly lower, but that of TFLX was significantly higher than that reported in all previous data concordant with the amount of recent antimicrobial use. Therefore, continuation of appropriate antimicrobial use for M. pneumoniae infection is important.

Macrolide versus Non-Macrolide in Combination with Steroids for the Treatment of Lobar or Segmental Mycoplasma pneumoniae Pneumonia Unresponsive to Initial Macrolide Monotherapy

In the last few decades, macrolide-resistant Mycoplasma pneumoniae (MRMP) has been increasing in proportion. This study aimed to evaluate the treatment outcomes of children with lobar or segmental MP pneumonia unresponsive to the initial 3−5-day macrolide therapy, who then switched to either a non-macrolide, macrolide + steroid, or a non-macrolide + steroid regimen, according to the 2019 KSPID and KAPARD guideline during the 2019−2020 Mycoplasma epidemic in South Korea. A total of 190 patients <18 years old were admitted during the study period for MP lobar or segmental pneumonia, and 16.8% (n = 32/190) were responsive to the initial macrolide monotherapy, whereas 83.2% (158/190) were refractory. The median age of the patients was 7 (interquartile range [IQR], 5−9) years old and 46.2% (n = 73/158) were male. The overall treatment success rates of non-macrolide, macrolide + steroid, and non-macrolide + steroid groups were 46.2%, 80.8%, and 100.0%, respectively. Patients in the non-macrolide + steroid group had the shortest fever duration after a regimen change of 1 (IQR, 0−3) day compared with patients in the non-macrolide group and macrolide + steroid group; 2 (IQR, 1−4) days and 2 (IQR, 1−3.3) days (p = 0.004), respectively. Follow-up CRP (ß, 0.169; CI, 0.050−0.287; p = 0.006), macrolide + steroid therapy (ß, −1.694; CI, −2.463−−0.925; p < 0.001), and non-macrolide+ steroid therapy (ß, −2.224; CI, −3.321−−1.127; p < 0.001) were shown to be significantly associated with the duration of fever after admission. To conclude, in patients with severe MP pneumonia that failed to respond to the initial macrolide therapy, a non-macrolide + steroid had the highest treatment success rate and a shorter duration of fever.

Global Trends in the Proportion of Macrolide-Resistant Mycoplasma pneumoniae Infections: A Systematic Review and Meta-analysis

IMPORTANCE

The proportion of macrolide-resistant Mycoplasma pneumoniae (MRMP) infections has changed, and it differs according to geographical region.

OBJECTIVE

To analyze the global patterns, including the temporal trends, regional variations, and variant types, in the proportion of MRMP infections in this systematic review and meta-anaysis.

DATA SOURCES

PubMed, Cochrane Library, and Embase databases were searched for observational studies from inception to September 10, 2021.

STUDY SELECTION

Observational studies reporting the proportion of MRMP infections were screened independently by 2 authors. The presence of MRMP infection was defined as any case of M pneumoniae infection positive for any variants associated with macrolide resistance identified using respiratory samples.

DATA EXTRACTION AND SYNTHESIS

Data were extracted independently and in duplicate by 2 reviewers. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline was used. Random-effects meta-analyses were used to estimate the proportion of MRMP infections.

MAIN OUTCOMES AND MEASURES

The global patterns in the proportion of MRMP infections were estimated, and the temporal trends and variant types of MRMP infection with regional differences were investigated.

RESULTS

This study included 153 studies from 150 articles (27 408 samples in 26 countries) in the meta-analysis. The global patterns in the proportion of MRMP infections showed an increasing trend with regional differences. The proportion of MRMP infections was highest in the Western Pacific regions (53.4%; 95% CI, 47.4%-60.3%), followed by the South East Asian region (9.8%; 95% CI, 0.8%-100%), the region of the Americas (8.4%; 95% CI, 6.1%-11.6%), and the European region (5.1%; 95% CI, 3.3%-8.0%). The most commonly identified variant of MRMP infection was A2063G (96.8%; 95% CI, 95.8%-97.7%), followed by A2064G (4.8%; 95% CI, 3.5%-6.7%). The proportion of MRMP infections was the highest in studies including only children (37.0%; 95% CI, 29.8%-46.1%), followed by those including only adults (15.9%; 95% CI, 6.4%-39.7%) and those including both children and adults (16.7%; 95% CI, 10.1%-27.6%).

CONCLUSIONS AND RELEVANCE

This study provides global trends in the proportion of MRMP infections and suggests that strategies to prevent the spread of MRMP infection and to treat MRMP infections are needed to decrease disease burden.

Clinical significance of respiratory virus coinfection in children with Mycoplasma pneumoniae pneumonia

BACKGROUND

The prevalence of refractory Mycoplasma pneumoniae (MP) pneumonia has been increasing. However, few studies have investigated the impact of respiratory virus coinfection in patients with MP pneumonia, and their results have been inconclusive. This study aimed to investigate the impact of respiratory virus coinfection in children hospitalized with MP pneumonia.

METHODS

This study enrolled 145 children hospitalized with MP pneumonia between May 2019 and March 2020. The patients were divided into two groups: the respiratory virus coinfection and non-coinfection groups. All the children underwent polymerase chain reaction testing for respiratory virus infection. Information on clinical, laboratory, and radiologic findings were obtained retrospectively via medical chart reviews.

RESULTS

Children in the respiratory virus coinfection group were younger than those in the non-coinfection group. Respiratory virus coinfection in children hospitalized with MP pneumonia was significantly associated with persistence of fever more than 6 days (adjusted odds ratio [aOR], 2.394; 95% confidence interval [95% CI], 1.172-4.892), severe pneumonia (aOR, 4.602; 95% CI, 1.154-18.353), and poor response to the stepwise approach for MP pneumonia (aOR, 4.354; 95% CI, 1.374-13.800). In addition, higher levels of liver enzymes and lactate dehydrogenase at admission were associated with respiratory virus coinfection in children with MP pneumonia.

CONCLUSIONS

The results of this study suggest that respiratory virus coinfection in children hospitalized with MP pneumonia may be associated with refractory MP pneumonia.

Clinical significance of Mycoplasma pneumoniae specific IgM titer in children hospitalized with Mycoplasma pneumoniae pneumonia

BACKGROUND

The present study aimed to identify the clinical significance of Mycoplasma pneumoniae (MP)-specific immunoglobulin M (IgM) titer, in addition to a diagnosis of MP infection, in children with MP pneumonia.

METHODS

This study was performed in 155 children hospitalized with MP pneumonia. The clinical features and laboratory and radiographic findings on admission in children with positive or negative MP-specific IgM titers were retrospectively reviewed from the electronic medical records.

RESULTS

The mean age of the included children was 6.0 years, and 118 (76.1%) of the children were positive for MP-specific IgM. A longer duration between symptom onset and admission (adjusted odds ratio [aOR] 1.47, 95% confidence interval [CI] 1.24-1.75), longer duration of symptoms during the illness (aOR 1.15, 95% CI 1.02-1.30), and development of extra-pulmonary manifestations (aOR 9.16, 95% CI 1.96-42.81) were significantly associated with a positive MP-specific IgM titer. Serum lactate dehydrogenase levels (aOR 1.00, 95% CI 1.00-1.01) and pneumonic infiltration involving > 50% of the total lung volume on chest radiography (aOR 4.68, 95% CI 1.12-19.55) were associated with positive MP-specific IgM in children with MP pneumonia. A poor response to stepwise treatment for MP pneumonia was more common in children with a positive MP-specific IgM titer than those with a negative MP-specific IgM titer on admission.

CONCLUSIONS

A positive MP-specific IgM titer at diagnosis of MP pneumonia may partially suggest an exaggerated immune response with a higher disease burden compared to children with MP pneumonia with a negative MP-specific IgM titer.

Recent Trends in the Epidemiology, Diagnosis, and Treatment of Macrolide-Resistant Mycoplasma pneumoniae

Among Mycoplasma pneumoniae (MP) is one of the major pathogens causing lower respiratory tract infection. Macrolide-resistant Mycoplasma pneumoniae (MRMP) isolates have been increasing and has become a global concern, especially in East Asian countries. This affects the treatment of MP infection; that is, some patients with MRMP infections fever cannot be controlled despite macrolide therapy. Therefore, alternative therapies, including secondary antimicrobials, including tetracyclines, fluoroquinolones, or systemic corticosteroids, were introduced. However, there are insufficient data on these alternative therapies. Thus, this article provides reviews of the recent trends in the epidemiology, diagnosis, and treatment of MRMP.

Macrolide Resistance in Mycoplasma pneumoniae, Midwestern United States, 2014 to 2021

The epidemiology of macrolide resistance in Mycoplasma (Mycoplasmoides) pneumoniae in the United States is incompletely described. Using a PCR assay targeting common mutations associated with macrolide resistance in M. pneumoniae (23S rRNA gene, A2063G/A2064G), the frequency of macrolide resistance was estimated to be 10% based on analysis of 114 samples tested from January 2014 to September 2021 at Mayo Clinic Laboratories. Seasonality data showed the highest rates of M. pneumoniae infection in the fall/early winter.

Persistent high macrolide resistance rate and increase of macrolide-resistant ST14 strains among Mycoplasma pneumoniae in South Korea, 2019-2020

BACKGROUND

Expansion of the single sequence type 3 (ST3) was associated with a high macrolide resistance rate among Mycoplasma pneumoniae in Korea during the 2014-2016 epidemic. This study investigates the macrolide resistance rate and genetic diversity of the subsequent epidemic of M. pneumoniae pneumonia in 2019-2020.

METHODS

The culture for M. pneumoniae was developed from 1228 respiratory samples collected from children with pneumonia in four hospitals in Korea between January 2019 and January 2020. Determination of macrolide resistance and multilocus sequence typing analysis were performed on M. pneumoniae isolates. eBURST analysis was applied to estimate the relationships among strains and to assign strains to a clonal complex.

RESULTS

M. pneumoniae was cultured in 93 (7.6%) of 1228 clinical samples. The overall macrolide resistance rate of M. pneumoniae strains was 78.5% (73/93). Of the nine STs identified, three were novel. The most common ST was ST3 (66 [71.0%]) followed by ST14 (18 [19.4%]) and ST7/ST15 (2 [2.2%] each). Three STs (ST3, ST14, and ST17) exhibited macrolide resistance. The macrolide resistance rates of ST3 and ST14 were 98.5% (65 of 66) and 38.9% (7 of 18), respectively.

CONCLUSION

Compared to the previous outbreak in 2014-2016, the overall macrolide resistance remained high; however, an increasing proportion of macrolide resistance was observed within ST14 strains in 2019-2020.