Definition
Legionnaire’s Disease is an acute bronchopneumonia produced by gram-negative bacillus,Legionella pneumophila. It derives its name and notoriety from the peculiar and highly publicized disease that struck 182 (29 of whom died) at an American Legion convention in Philadelphia in July 1976.
Etiology
It is caused by Legionella pneumophilla, which is an aerobic, gram-negative bacillus which flourishes on soils and transmitted airborne through cooling towers and air-conditioning systems.
Risk Factors
The following people are at risk:
- Middle-age and elderly people
- Immunocompromised patients or those with lymphoma or other disorders associated with delayed hypersensitivity.
- Patients with chronic underlying diseases, such as diabetes, chronic renal failure, or chronic obstructive pulmonary disease.
- Those with alcoholism
- Cigarette smokers
- Those on a ventilator for extended periods
Incubation Period
It has an incubation period around 2 to 10 days.
Manifestations
- diarrhea
- anorexia
- malaise
- diffuse myalgias
- and generalized weakness
- headache
- and recurrent chills
- blood-tinged sputum
Diagnostic Findings
- White Blood Count would show leukocytosis
- Chest Xray would show consolidations
- Auscultation would show fine crackles
- Definitive tests include direct immunofluorescence of respiratory tract secretions and tissue, culture of L. pneumophilia, and indirect fluorescent antibody testing of serum comparing acute samples with convalescent samples drawn at least 3 weeks later. A convalescent serum showing a fourfold or greater rise in antibody titer for Legionella confirms the diagnosis.
Treatment
- Quinolones (ciprofloxacin)
- Macrolides (erythromycin)
Nursing Management
- Closely monitor the patient’s respiratory status
- Continually monitor the patient’s vital signs
- Replace fluid and electrolytes
- Provide mechanical ventilation and other respiratory therapy
- Give antibiotic therapy as indicated
