Mycoplasma pneumoniae Infection

Mycoplasmas, the smallest self-replicating organisms, include M. pneumoniae (pneumonia), M. genitalium, and Ureaplasma urealyticum (urethritis). M. pneumoniae is a common cause of community-acquired pneumonia.

Tabs Content

Clinical Overview

Diagnosis

Indications for Testing

Mild illness consisting of upper or lower respiratory illness with gradual onset of
- Malaise
- Fever
- Headache
- Sore throat
- Persistent cough
- Atypical pneumonia appearance on chest x-ray (patchy unilateral or diffuse bilateral infiltrates)
Appearance of extrapulmonary symptoms in addition to severe pneumonia – usually prompts testing
- Rash, including Stevens-Johnson syndrome
- Hemolysis, secondary to IgM cold agglutinins
- Cardiac involvement including conduction disturbances, arrhythmias, congestive heart failure, and chest pain
- Central nervous system (CNS) involvement
- Gastrointestinal manifestations, eg, nausea, vomiting, and diarrhea
- Joint pain
If indications are not present, testing for Mycoplasma pneumoniae is not indicated as this is usually a mild, self-limited disease that responds to macrolide antibiotics

Laboratory Testing

Polymerase chain reaction (PCR)
- Rapid test to identify M. pneumoniae
- Increased sensitivity if sputum is tested and infection is in early stage (first 21 days after onset)
- Probably most sensitive test to use, especially in adults who may not mount significant IgM levels early in infection
IgG, IgM by enzyme-linked immunosorbent assay (ELISA), complement fixation
- Usually requires acute and convalescent samples
- Not effective in early diagnosis
Cold agglutinins – especially if hemolysis is present or suspected
- Negative result does not rule out infection
  - 30-50% of patients with M. pneumoniae will develop cold agglutinins (Fischbach, 2009)
Culture
- Inadequate for acute diagnosis
- Not recommended; bacteria are relatively fastidious and require a long incubation (up to 4 weeks)
Consider concurrent testing for Chlamydia pneumoniae, urinary antigen detection for Legionella, viral studies (eg, PCR panel) for respiratory viruses

Imaging Studies

Chest radiography – patchy unilateral infiltrates or diffuse bilateral interstitial process

Differential Diagnosis

Background

Epidemiology

Prevalence
- Responsible for 15-20% of all community-acquired pneumonia; higher rates among school children and people in closed populations (military recruits)
- 2-5% of patients require hospitalization as compared with 15-20% hospitalization rates for other causes of pneumonia
Transmission
- Respiratory droplet
- Most common in U.S. during late summer to early fall

Organism

M. pneumoniae
- Flask-shaped bacteria with no true cell wall and a very small genome (816 kilobase pairs)
- Facultative intracellular parasite
- Cultivation in vitro is difficult
  - Fastidious nature
  - Dependence on externally supplied growth factors (by host organism or in culture medium)
  - Limited metabolic capacity inherent in small genome

Clinical Presentation

Most infections are mild and often indistinguishable from other viral and atypical bacterial pathogens
Initial symptoms
- Malaise, myalgias, sore throat, headache (retro-orbital), ear pain, and fever
Advanced infection
- Dry, nonproductive cough occurs 3-5 days after onset of initial nonspecific symptoms
- Cough may produce mucopurulent sputum later in illness
- May be accompanied by chills, chest pain, shortness of breath, nausea, vomiting, diarrhea
- Patients usually seek medical attention after 5-7 days – cough may become paroxysmal and nocturnal
- Cough may persist several weeks following resolution of constitutional symptoms
- Pleural effusions more common in severe disease
Extrapulmonary manifestations of M. pneumoniae infection
- Syndromes caused by spread of organism
  - Bullous hemorrhagic otitis
  - Arthritis
  - Acute respiratory distress syndrome
  - Myocarditis with conduction disturbances and chest pain
  - Encephalitis/meningitis
  - Sinusitis
- Immunologically mediated syndromes
  - Hemolysis/hemolytic anemia
  - Skin rashes
  - Erythema nodosum or erythema multiforme
  - Thrombocytopenia
  - Guillain-Barré syndrome

ARUP Lab Tests

Detect M. pneumoniae bacteria

Mycoplasma pneumoniae by PCR 0060256

Method: Qualitative Polymerase Chain Reaction

Aid in diagnosis of M. pneumoniae in patient with persistent pneumonia that is outside of the expected acute phase

Mycoplasma pneumoniae Antibodies, IgG & IgM 0050399

Method: Semi-Quantitative Enzyme-Linked Immunosorbent Assay

Detect respiratory pathogens in patients with pneumonia

Explify Respiratory Pathogen Detection by Next Generation Sequencing 3002026

Method: Massively Parallel Sequencing

Cold Agglutinins 0050175

Method: Semi-Quantitative Hemagglutination

Related Tests

Panel that combines M. pneumoniae IgG and IgM antibodies is preferred

Low IgM antibody levels may persist more than 12 months postinfection

Mycoplasma pneumoniae Antibody, IgM 0050398

Method: Semi-Quantitative Enzyme-Linked Immunosorbent Assay

Panel that combines M. pneumoniae IgG and IgM antibodies is preferred

Mycoplasma pneumoniae Antibody, IgG 0050397

Method: Semi-Quantitative Enzyme-Linked Immunosorbent Assay

Preferred test to confirm respiratory syncytial virus (RSV) or influenza in general inpatients and RSV in adults

Respiratory Virus Mini Panel by PCR 0060764

Method: Qualitative Reverse Transcription Polymerase Chain Reaction

Preferred test for evaluating severely immunocompromised (eg, bone marrow transplant [BMT]) or critically ill (ICU) patients with respiratory symptoms

Detect influenza (A H1, A H3, A 2009 H1N1, B), RSV (A, B), parainfluenza (1, 2, 3), human metapneumovirus (hMPV), human rhinovirus, and adenovirus (B/E, C)

Respiratory Viral Panel by PCR 3001479

Method: Qualitative Polymerase Chain Reaction

Detect C. pneumoniae in bronchoalveolar lavage (BAL), nasal wash, nasopharyngeal swab, or pleural fluid

Chlamydia pneumoniae by PCR 0060715

Method: Qualitative Polymerase Chain Reaction

Differentiate between Chlamydophila species (C. psittaci, C. pneumoniae)

Differentiate early IgM response to infection from persistent low-level titer

Because of cross-reactivity, a C. pneumoniae-specific reaction will exhibit titers 2-fold or greater than C. trachomatis or C. psittaci serology

Limited value in diagnosis of most oculogenital (eg, eyes, genitalia) chlamydial infections

Chlamydia Antibody Panel, IgG & IgM by IFA 0065100

Method: Semi-Quantitative Indirect Fluorescent Antibody

Provide retrospective evidence of suspected L. pneumophila infection

Legionella pneumophila Antigen, Urine 0070322

Method: Qualitative Enzyme-Linked Immunosorbent Assay

Medical Experts

Couturier, Marc Roger, PhD, D(ABMM), Medical Director, Microbial Immunology, Parasitology and Fecal Testing, and Infectious Disease Antigen Testing at ARUP Laboratories; Associate Professor of Clinical Pathology, University of Utah

Hillyard, David R., MD, Medical Director, Molecular Infectious Diseases at ARUP Laboratories; Professor of Pathology, University of Utah

References

General References

Atkinson TP, Balish MF, Waites KB. Epidemiology, clinical manifestations, pathogenesis and laboratory detection of Mycoplasma pneumoniae infections. FEMS Microbiol Rev. 2008; 32(6): 956-73. PubMed

Fischbach F, Dunning M. Chapter 8: Overview of Immunodiagnostic Studies. A Manual of Laboratory and Diagnostic Tests, 8th. Philadelphia: Lippincott Williams & Wilkins, 2009.

Loens K, Goossens H, Ieven M. Acute respiratory infection due to Mycoplasma pneumoniae: current status of diagnostic methods. Eur J Clin Microbiol Infect Dis. 2010; 29(9): 1055-69. PubMed

Thurman KA, Walter ND, Schwartz SB, Mitchell SL, Dillon MT, Baughman AL, Deutscher M, Fulton JP, Tongren JE, Hicks LA, Winchell JM. Comparison of laboratory diagnostic procedures for detection of Mycoplasma pneumoniae in community outbreaks. Clin Infect Dis. 2009; 48(9): 1244-9. PubMed

Waites KB. What's new in diagnostic testing and treatment approaches for Mycoplasma pneumoniae infections in children? Adv Exp Med Biol. 2011; 719: 47-57. PubMed

Zhang L, Zong Z, Bin Liu Y, Ye H, Lv X. PCR versus serology for diagnosing Mycoplasma pneumoniae infection: a systematic review & meta-analysis. Indian J Med Res. 2011; 134: 270-80. PubMed

Resources from the ARUP Institute for Clinical and Experimental Pathology®

Diaz MH, Benitez AJ, Cross KE, Hicks LA, Kutty P, Bramley AM, Chappell JD, Hymas W, Patel A, Qi C, Williams DJ, Arnold SR, Ampofo K, Self WH, Grijalva CG, Anderson EJ, McCullers JA, Pavia AT, Wunderink RG, Edwards KM, Jain S, Winchell JM. Molecular detection and characterization of Mycoplasma pneumoniae among patients hospitalized with community-acquired pneumonia in the United States. Open Forum Infect Dis. 2015; 2(3): ofv106. PubMed

Diaz MH, Cross KE, Benitez AJ, Hicks LA, Kutty P, Bramley AM, Chappell JD, Hymas W, Patel A, Qi C, Williams DJ, Arnold SR, Ampofo K, Self WH, Grijalva CG, Anderson EJ, McCullers JA, Pavia AT, Wunderink RG, Edwards KM, Jain S, Winchell JM. Identification of bacterial and viral codetections with Mycoplasma pneumoniae using the TaqMan Array Card in patients hospitalized with community-acquired pneumonia. Open Forum Infect Dis. 2016; 3(2): ofw071. PubMed

Dunn JJ, Malan AK, Evans J, Litwin CM. Rapid detection of Mycoplasma pneumoniae IgM antibodies in pediatric patients using ImmunoCard Mycoplasma compared to conventional enzyme immunoassays. Eur J Clin Microbiol Infect Dis. 2004; 23(5): 412-4. PubMed

Content Review:

September 2017

Last Update: November 2019

Mycoplasma pneumoniae Infection

Diagnosis

Indications for Testing

Laboratory Testing

Imaging Studies

Differential Diagnosis

Background

Epidemiology

Organism

Clinical Presentation

ARUP Lab Tests

Medical Experts

References

General References

Resources from the ARUP Institute for Clinical and Experimental Pathology®

ARUP Laboratories

ARUP Websites

ARUP Consult


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	Mycoplasma pneumoniae Infection. ARUP Consult^©. Retrieved November 18, 2019, from: https://arupconsult.com/content/mycoplasma-pneumoniae

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Mycoplasma pneumoniae Infection

Diagnosis

Indications for Testing

Laboratory Testing

Imaging Studies

Differential Diagnosis

Background

Epidemiology

Organism

Clinical Presentation

ARUP Lab Tests

Medical Experts

References

General References

Resources from the ARUP Institute for Clinical and Experimental Pathology®

ARUP Laboratories

ARUP Websites

ARUP Consult