Table 2.
Less common causes of pneumonia in children
| Organism | Risk factors or clinical scenarios |
|---|---|
| Human metapneumovirus | Similar in epidemiology and presentation to respiratory syncytial virus |
| Bordetella pertussis | Peak incidence in infants and adolescents; exposure to adults with cough illness |
| Mycobacterium tuberculosis | Most common cause in developing world; travel to endemic region or exposure to high-risk individuals |
| Listeria monocytogenes | Component of early-onset septicemia in infants from birth to 3 weeks of age; in older patients, ingestion of contaminated food or unpasteurized dairy products (disease often seen in pregnant women) |
| Cytomegalovirus | Infants with congenital/perinatal infection or part of disseminated illness in immunocompromised hosts |
| Varicella-zoster virus and herpes simplex virus | May cause pneumonia/pneumonitis as part of disseminated disease |
| Legionella pneumophila | Exposure to contaminated water supply |
| Coccidioides immitis | Travel to endemic region (southwest United States) |
| Histoplasma capsulatum | Travel to endemic region (Ohio and Mississippi River valley) |
| Blastomyces dermatitidis | Travel to endemic region (Ohio and Mississippi River valley) |
| Chlamydophila psittaci | Exposure to birds (parakeets) |
| Hantavirus | Exposure to mouse droppings |
| Coxiella burnetii | Exposure to sheep |
| Brucella abortis | Exposure to cattle or goats; ingestion of unpasteurized dairy products |
| Coronavirus | Associated with severe acute respiratory syndrome (SARS); travel to affected region (particularly Asia) |
| Avian influenza (influenza A: H5, H7, H9) | Exposure to birds; travel to affected region (Asia) |
| Francisella tularensis | Exposure to animals (rabbits); bioterrorist activity |
| Yersinia pestis | Exposure to rats; bioterrorist activity |
| Bacillus anthracis | Exposure to infected animals; bioterrorist activity |