By Susan Simmons, PhD, RN, ARNP-BC
Recognizing and preventing
CONSIDERED AN ATYPICAL pneumonia, mycoplasmal pneumonia is one of the most common types of community-acquired pneumonia in otherwise healthy people under age 40. It’s caused by Mycoplasma pneumoniae, an interstitial bacterium that spreads in respiratory droplets. Unlike typical community-acquired pneumonia,which is usually caused by pneumococcal pneumonia, it’s most likely to strike children and young adults age 5 to 20, and is often mistaken for asthma.1
Although most patients with M. pneumoniae don’t develop pneumonia, those with comorbid conditions (especially involving the lower respiratory tract) are at risk for seriousrespiratory distress. With community-acquired infections becoming more prevalent, it’s essential to recognize the signs and symptoms early in order to treat the infection before it spreads. Walking through the signs and symptoms Sometimes called walking pneumonia, mycoplasmal pneumonia is most common in the summer and fall. Outbreaks in communities tend to be cyclical, occurring every 3 to 8 years.Hallmarks of the disease are a long, insidious onset and a long, gradual recovery. Wheezing and coughing are also characteristic, explaining why the illness is sometimes misdiagnosed as asthma. Most patients recover without complications in several weeks, but the infection may cause pneumonia in children and acute chest syn-
• its ability to produce the damaging oxygen free radicals hydrogen peroxideand superoxide, which damage cells and cause inflammation.1,3 Ciliary paralysis, cell damage, and inflammation of the respiratory tract lead to coughing and may result in lower respiratory tract infection. Recognizing mycoplasmal pneumonia When assessing a patient for possible M. pneumoniae infection, look for the following. • upper respiratory tract signs and symptoms: pharyngitis, rhinorrhea •lower respiratory tract signs and symptoms: crackles, rhonchi, wheezes, dyspnea, nonproductive cough, chest pain • fever, chills, otalgia, and malaise. Fever typically lasts more than 3 days. A prolonged fever, combined with the patient’s history and other signs and symptoms, helps identify mycoplasmal pneumonia, especially when illnesses such as strep throat, acute otitis media, and sinusitis havebeen ruled out. Keep in mind, however, that disease presentation is variable: 50% to 75% of patients with M. pneumoniae infection may develop only pharyngitis, otalgia, rhinorrhea, and fever. Otalgia associated with M. pneumoniae may be caused by bullous myringitis, which is manifested as a lesion on the tympanic membrane. This lesion is a confirmatory finding of M. pneumoniae infection. Onphysical exam, other clinical findings may include a nontoxic
Signs and symptoms of mycoplasmal pneumonia include wheezing and coughing, so it’s often misdiagnosed as asthma.
drome in patients with sickle-cell disease.1 M. pneumoniae has a long incubation period (1 to 4 weeks).2 The gradual onset and length of the illness reflect M. pneumoniae’s distinctive properties: • itsaffinity for both ciliary and nonciliary epithelial cells of the respiratory tract
When the course gets complicated
Common complications in patients with mycoplasmal pneumonia include pleural effusion, empyema, respiratory distress syndrome, and respiratory failure.4,5 Other complications include: • cardiovascular: endocarditis, myocarditis, or pericarditis1,4 • neurologic: aseptic meningitis,encephalitis, Guillain-Barré syndrome, transverse myelitis1,4 • dermatologic: erythema multiforme, erythema nodosum, Stevens-Johnson syndrome, urticaria • hematologic: patients with sickle-cell disease are at increased risk for hemolytic anemia and thrombocytopenia.1,4 African American and Asian patients with hemoglobinopathies are also at risk for severe pleural effusions and marked respiratory...