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Clinical Microbiology Reviews Jul 2017is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several... (Review)
Review
is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several years there has been much new information published concerning infections caused by this organism. New molecular-based tests for detection are now commercially available in the United States, and advances in molecular typing systems have enhanced understanding of the epidemiology of infections. More strains have had their entire genome sequences published, providing additional insights into pathogenic mechanisms. Clinically significant acquired macrolide resistance has emerged worldwide and is now complicating treatment. susceptibility testing methods have been standardized, and several new drugs that may be effective against this organism are undergoing development. This review focuses on the many new developments that have occurred over the past several years that enhance our understanding of this microbe, which is among the smallest bacterial pathogens but one of great clinical importance.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Humans; Molecular Epidemiology; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Respiratory System; United States
PubMed: 28539503
DOI: 10.1128/CMR.00114-16 -
Journal of Microbiology, Immunology,... Aug 2021Mycoplasma pneumoniae is a common pathogen that causes community-acquired pneumonia. In the past, M. pneumoniae was sensitive to macrolide antibiotics, and M. pneumoniae... (Review)
Review
Mycoplasma pneumoniae is a common pathogen that causes community-acquired pneumonia. In the past, M. pneumoniae was sensitive to macrolide antibiotics, and M. pneumoniae pneumonia (MPP) was usually a benign and self-limiting disease. However, despite use of the appropriate antibiotics, persistent fever and clinical deterioration may occur, leading to severe disease. Two major complicated conditions that may be clinically encountered are macrolide-resistant MPP and refractory MPP. Regarding the epidemics in Taiwan, before 2017, the mean rate of macrolide resistance was below 30%. Notably, since 2018, the prevalence of macrolide-resistant MPP in Taiwan has increased rapidly. Macrolide-resistant MPP shows persistent fever and/or no radiological regression to macrolide antibiotics and may even progress to severe and complicated pneumonia. Tetracyclines (doxycycline or minocycline) or fluoroquinolones are alternative treatments for macrolide-resistant MPP. Refractory MPP is characterized by an excessive immune response against the pathogen. In this context, corticosteroids have been suggested as an immunomodulator for downregulating the overactive host immune reaction. Overuse of macrolides may contribute to macrolide resistance, and thereafter, an increase in macrolide-resistant MPP. Delayed effective antimicrobial treatment is associated with prolonged and/or more severe disease. Thus, the appropriate prescription of antibiotics, as well as the rapid and accurate diagnosis of MPP, is important. The exact starting point, dose, and duration of the immunomodulator are yet to be established. We discuss these important issues in this review.
Topics: Anti-Bacterial Agents; Child; Community-Acquired Infections; Drug Resistance, Bacterial; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Prevalence; Taiwan; Treatment Outcome
PubMed: 33268306
DOI: 10.1016/j.jmii.2020.10.002 -
Current Microbiology Dec 2022Mycoplasma pneumoniae, an obligate parasitic pathogen without cell wall, can cause severe upper and lower respiratory tract symptoms. It is the pathogen of human... (Review)
Review
Mycoplasma pneumoniae, an obligate parasitic pathogen without cell wall, can cause severe upper and lower respiratory tract symptoms. It is the pathogen of human bronchitis and walking pneumonia, and named community-acquired pneumonia. In addition to severe respiratory symptoms, there are clinical extrapulmonary manifestations in the skin, brain, kidney, musculoskeletal, digestive system, and even blood system after M. pneumoniae infection. Hereby, we comprehensively summarized and reviewed the intrapulmonary and extrapulmonary pathogenesis of M. pneumoniae infection. The pathogenesis of related respiratory symptoms caused by M. pneumoniae is mainly adhesion damage, direct damage including nutrient predation, invasion and toxin, cytokine induced inflammation damage and immune evasion effect. The pathogenesis of extrapulmonary manifestations includes direct damage mediated by invasion and inflammatory factors, indirect damage caused by host immune response, and vascular occlusion. The intrapulmonary and extrapulmonary pathogenic mechanisms of M. pneumoniae infection are independent and interrelated, and have certain commonalities. In fact, the pathogenic mechanisms of M. pneumoniae are complicated, and the specific content is still not completely clear, further researches are necessary for determining the detailed pathogenesis of M. pneumoniae. This review can provide certain guidance for the effective prevention and treatment of M. pneumoniae infection.
Topics: Humans; Mycoplasma pneumoniae; Cell Wall; Cytokines; Inflammation; Kidney
PubMed: 36459213
DOI: 10.1007/s00284-022-03103-0 -
International Journal of Clinical... 2022(. ) is one of the leading causes of community-acquired pneumonia in children and is also implicated in a variety of reactive extrapulmonary diseases. Recurrent and/or... (Review)
Review
(. ) is one of the leading causes of community-acquired pneumonia in children and is also implicated in a variety of reactive extrapulmonary diseases. Recurrent and/or severe respiratory infections are one of the most frequent manifestations of several types of primary immunodeficiency. Here, we reviewed the medical literature to assess the potential relevance of . in the infections observed in children affected with combined, humoral, and innate primary immune deficiencies. . does not result to be epidemiologically prevalent as a cause of pneumonia in children affected by primary immunodeficiencies, but this infection can have a persistent or severe course in this category of patients. Indeed, the active search of . could be useful and appropriate especially in children with humoral immune deficiencies. Indeed, most cases of . infection in primary immunodeficiencies are described in patients affected by a/hypo-gammaglobulinemia.
Topics: Child; Community-Acquired Infections; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Primary Immunodeficiency Diseases
PubMed: 35855053
DOI: 10.1155/2022/6343818 -
The Pediatric Infectious Disease Journal Nov 2018
Review
Topics: Child; Clinical Laboratory Techniques; Community-Acquired Infections; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Polymerase Chain Reaction; Radiography
PubMed: 30169485
DOI: 10.1097/INF.0000000000002171 -
The Indian Journal of Medical Research Jan 2018Lower respiratory tract infections are considered a common cause responsible for morbidity and mortality among children, and Mycoplasma pneumoniae is identified to be... (Review)
Review
Lower respiratory tract infections are considered a common cause responsible for morbidity and mortality among children, and Mycoplasma pneumoniae is identified to be responsible for up to 40 per cent of community-acquired pneumonia in children greater than five years of age. Extrapulmonary manifestations have been reported either due to spread of infection or autoimmune mechanisms. Infection by M. pneumoniae has high incidence and clinical importance but is still an underrated disease. Most widely used serologic methods are enzyme immunoassays for detection of immunoglobulin M (IgM), IgG and IgA antibodies to M. pneumoniae, though other methods such as particle agglutination assays and immunofluorescence methods are also used. Detection of M. pneumoniae by nucleic acid amplification techniques provides fast, sensitive and specific results. Utilization of polymerase chain reaction (PCR) has improved the diagnosis of M. pneumoniae infections. Besides PCR, other alternative amplification techniques include (i) nucleic acid sequence-based amplification, (ii) Qβ replicase amplification, (iii) strand displacement amplification, (iv) transcription-mediated amplification, and (v) ligase chain reaction. Macrolides are used as the first-line treatment in childhood for M. pneumoniae infections; however, emergence of macrolide-resistant M. pneumoniae is a cause of concern. Development of a safe vaccine is important that gives protective immunity and would be a major step in reducing M. pneumoniae infections.
Topics: Adolescent; Anti-Bacterial Agents; Child; Child, Preschool; Community-Acquired Infections; Female; Humans; Immunoglobulin M; Infant; Male; Mycoplasma pneumoniae; Respiratory Tract Infections
PubMed: 29749357
DOI: 10.4103/ijmr.IJMR_1582_16 -
Indian Journal of Medical Microbiology 2016Genus Mycoplasma, belonging to the class Mollicutes, encompasses unique lifeforms comprising of a small genome of 8,00,000 base pairs and the inability to produce a cell... (Review)
Review
Genus Mycoplasma, belonging to the class Mollicutes, encompasses unique lifeforms comprising of a small genome of 8,00,000 base pairs and the inability to produce a cell wall under any circumstances. Mycoplasma pneumoniae is the most common pathogenic species infecting humans. It is an atypical respiratory bacteria causing community acquired pneumonia (CAP) in children and adults of all ages. Although atypical pneumonia caused by M. pneumoniae can be managed in outpatient settings, complications affecting multiple organ systems can lead to hospitalization in vulnerable population. M. pneumoniae infection has also been associated with chronic lung disease and bronchial asthma. With the advent of molecular methods of diagnosis and genetic, immunological and ultrastructural assays that study infectious disease pathogenesis at subcellular level, newer virulence factors of M. pneumoniae have been recognized by researchers. Structure of the attachment organelle of the organism, that mediates the crucial initial step of cytadherence to respiratory tract epithelium through complex interaction between different adhesins and accessory adhesion proteins, has been decoded. Several subsequent virulence mechanisms like intracellular localization, direct cytotoxicity and activation of the inflammatory cascade through toll-like receptors (TLRs) leading to inflammatory cytokine mediated tissue injury, have also been demonstrated to play an essential role in pathogenesis. The most significant update in the knowledge of pathogenesis has been the discovery of Community-Acquired Respiratory Distress Syndrome toxin (CARDS toxin) of M. pneumoniae and its ability of adenosine diphosphate (ADP) ribosylation and inflammosome activation, thus initiating airway inflammation. Advances have also been made in terms of the different pathways behind the genesis of extrapulmonary complications. This article aims to comprehensively review the recent advances in the knowledge of pathogenesis of this organism, that had remained elusive during the era of serological diagnosis. Elucidation of virulence mechanisms of M. pneumoniae will help researchers to design effective vaccine candidates and newer therapeutic targets against this agent.
Topics: Asthma; Bacterial Proteins; Bacterial Toxins; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Virulence Factors
PubMed: 26776112
DOI: 10.4103/0255-0857.174112 -
Nihon Saikingaku Zasshi. Japanese... 2015Mycoplasmas are smallest organisms capable of self-replication and cause various diseases in human. Especially, Mycoplasma pneumoniae is known as an etiological agent of... (Review)
Review
Mycoplasmas are smallest organisms capable of self-replication and cause various diseases in human. Especially, Mycoplasma pneumoniae is known as an etiological agent of pneumonia. From 2010 to 2012, epidemics of M. pneumoniae infections were reported worldwide (e.g., in France, Israel, and Japan). In the diseases caused by mycoplasmas, strong inflammatory responses induced by mycoplasmas have been thought to be important. However, mycoplasmas lack of cell wall and do not possess inflammation-inducing endotoxin such as lipopolysaccharide (LPS). We purified inflammation-inducing factors from pathogenic mycoplasmas and identified that they were lipoproteins. Lipoproteins derived from mycoplasmas induced inflammatory responses through Toll-like receptor (TLR) 2. In addition, we demonstrated that cytadherent property of M. pneumoniae played an important role in induction of inflammatory responses. Cytadherent property of M. pneumoniae induced inflammatory responses through TLR2 independent pathway. TLR4, inflammasomes, and autophagy were involved in this TLR2 independent induction of inflammatory responses.
Topics: Autophagy; Bacterial Adhesion; Bacterial Translocation; Humans; Inflammasomes; Lipoproteins; Mycoplasma; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Toll-Like Receptor 2; Toll-Like Receptor 4
PubMed: 26632216
DOI: 10.3412/jsb.70.369 -
Clinical Infectious Diseases : An... Jan 2019The epidemiology of Mycoplasma pneumoniae (Mp) among US children (<18 years) hospitalized with community-acquired pneumonia (CAP) is poorly understood.
BACKGROUND
The epidemiology of Mycoplasma pneumoniae (Mp) among US children (<18 years) hospitalized with community-acquired pneumonia (CAP) is poorly understood.
METHODS
In the Etiology of Pneumonia in the Community study, we prospectively enrolled 2254 children hospitalized with radiographically confirmed pneumonia from January 2010-June 2012 and tested nasopharyngeal/oropharyngeal swabs for Mp using real-time polymerase chain reaction (PCR). Clinical and epidemiological features of Mp PCR-positive and -negative children were compared using logistic regression. Macrolide susceptibility was assessed by genotyping isolates.
RESULTS
One hundred and eighty two (8%) children were Mp PCR-positive (median age, 7 years); 12% required intensive care and 26% had pleural effusion. No in-hospital deaths occurred. Macrolide resistance was found in 4% (6/169) isolates. Of 178 (98%) Mp PCR-positive children tested for copathogens, 50 (28%) had ≥1 copathogen detected. Variables significantly associated with higher odds of Mp detection included age (10-17 years: adjusted odds ratio [aOR], 10.7 [95% confidence interval {CI}, 5.4-21.1] and 5-9 years: aOR, 6.4 [95% CI, 3.4-12.1] vs 2-4 years), outpatient antibiotics ≤5 days preadmission (aOR, 2.3 [95% CI, 1.5-3.5]), and copathogen detection (aOR, 2.1 [95% CI, 1.3-3.3]). Clinical characteristics were non-specific.
CONCLUSIONS
Usually considered as a mild respiratory infection, Mp was the most commonly detected bacteria among children aged ≥5 years hospitalized with CAP, one-quarter of whom had codetections. Although associated with clinically nonspecific symptoms, there was a need for intensive care in some cases. Mycoplasma pneumoniae should be included in the differential diagnosis for school-aged children hospitalized with CAP.
Topics: Adolescent; Child; Child, Preschool; Community-Acquired Infections; Female; Hospitalization; Humans; Infant; Infant, Newborn; Male; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Prospective Studies; United States
PubMed: 29788037
DOI: 10.1093/cid/ciy419 -
Frontiers in Cellular and Infection... 2023, as one of the most common pathogens, usually causes upper respiratory tract infections and pneumonia in humans and animals. It accounts for 10% to 40% of... (Review)
Review
, as one of the most common pathogens, usually causes upper respiratory tract infections and pneumonia in humans and animals. It accounts for 10% to 40% of community-acquired pneumonia in children. The alveolar epithelial cells (AECs) are the first barrier against pathogen infections, triggering innate immune responses by recruiting and activating immune cells when pathogens invade into the lung. Alveolar macrophages (AMs) are the most plentiful innate immune cells in the lung, and are the first to initiate immune responses with pathogens invasion. The cross-talk between the alveolar epithelium and macrophages is necessary to maintain physiological homeostasis and to eradicate invaded pathogen by regulating immune responses during infections. This review summarizes the communications between alveolar macrophages and epithelial cells during infections, including cytokines-medicated communications, signal transduction by extracellular vesicles, surfactant associated proteins-medicated signal transmission and establishment of intercellular gap junction channels.
Topics: Child; Animals; Humans; Pneumonia, Mycoplasma; Macrophages, Alveolar; Mycoplasma pneumoniae; Lung; Epithelial Cells
PubMed: 37113130
DOI: 10.3389/fcimb.2023.1052020