Lung
Infectious
Bacterial
Mycoplasma pneumoniae
Author: Elliot Weisenberg, M.D.
Last author update: 1 September 2011
Last staff update: 9 August 2020
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed search: mycoplasma pneumoniae [title] pneumonia pulmonary
Table of Contents
Definition / general | Clinical features | Treatment | Gross description | Microscopic (histologic) description | Videos | Differential diagnosisCite this page: Weisenberg E. Mycoplasma pneumoniae. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungnontumormycoplasma.html. Accessed December 25th, 2024.
Definition / general
- Strict aerobe that lacks a true cell wall, 0.2 - 0.8 μm and among the smallest free living bacterias
- Formerly called atypical pneumonia (atypical due to moderate sputum production and consolidation and only minimal leukocytosis)
Clinical features
- Common in children and young adults, but may occur in older age groups
- Causes community acquired pneumonia (eMedicine), either interstitial (usually) or bronchopneumonia (rare)
- Often asymptomatic
- Superimposed bacterial infection may occur
- Diagnosis: rarely biopsied, diagnose with complement fixation antigen assays; cold agglutinins present in 50% of cases
Treatment
- Macrolides (erythromycin), although may be resistance (J Infect Chemother 2011;17:114)
Gross description
- Reddish blue, congested, patchy lungs; usually no pleuritis
Microscopic (histologic) description
- Bronchiolitis, interstitial and minimal intra-alveolar involvement with widened alveolar septa due to lymphoplasmacytic inflammatory cells
- Intra-alveolar proteinaceous material
- Neutrophilic infiltrate in bronchioles acutely, bronchiolar metaplasia, lymphoplasmacytic infiltrate in bronchial wall and pneumocyte hyperplasia
Videos
Gliding phase
Differential diagnosis
- Respiratory syncytial virus, rhinovirus, rubeola, varicella, Chlamydia psittacosis, Coxiella burnetti (Q fever)
