Christina Riggall, BS, RN, CNRN SUNY Institute of Technology
Legionella is a bacteria that first found in July 1976 during an American Legion Convention where it caused the death of 34 delegates. At the time the cause of illness was unknown. It wasn’t until January 1977 that the bacteria was isolated and identified. Legionella is a common cause of community- acquired and nosocomial-acquired pneumonia. It is estimated that 25,000 people in the US develop Legionnaires’ disease each year. (Lane, Ferrari, & Dreher,,2004 / NYS DOH, 2004)
When the organism is inhaled, it attaches to the respiratory epithelial cells and the alveolar macrophages. The bacterium most often causes pneumonia but can also cause flu-like symptoms known as Pontiac fever. This occurs hours after exposure to the bacteria. Legionnaires’ disease occurs 2-14 days after exposure to the bacteria. (CDC, 2013 / Pedrot-Betot, Stout, & Yu, 2013)
Legionella is an aerobic, gram-negative bacilli There are over 50 species of legionella, L. pneumophila is the most common, accounting for 80% of human infections. Pedrot-Betot, Stout, & Yu, 2013
Successful diagnosis requires specialized lab tests. Legionnaires’ disease accounts for 2-9% of community acquired pneumonia The incidence has tripled from in both the U.S. and U.K.
Exposure to bodies of water, especially stagnant water. Man-made reservoirs cause the bacteria to grow and proliferate. In warm temperatures (25-42 ° C) the bacteria have increased growth Compost facilities or potting soil may also be a reservoir for legionella.
Chronic lung disease/smoking Older age (>50) Transplant recipients Immunosuppressants Tumor necrosis factor- alpha inhibitor Immunosuppressed children Neonates Recent repairs/maintenance to domestic plumbing. Recent travel CDC, 2013
Pneumonia Fevers Cough Pleuritic chest pain Headaches Watery diarrhea Neuro symptoms (seizure, confusion, disorientation, insomnia). (Domino, 2014) Body aches, Flu-like symptoms, malaise without pneumonia is known as Pontiac fever (CDC, 2013) CDC, 2013/ Domino, 2014
Legionnaires’ disease (482.84) Pneumonia due to other gram neg. bacteria (482.83) Pneumonia, unspecified organism (486) Without pneumonia present: Flu Pontiac fever (also caused by Legionella)
Ask about travel that occurred 14 days before onset of symptoms- 20% of Legionnaires’ disease is thought to be due to travel. The majority of cases are sporadic and outbreaks are rare. According to the NYS Dept. of Health, only outbreaks of the disease need to be investigated. (NYS DOH, 2004)
Legionella can be found in cooling towers, humidifiers, showers, hot tubs, ice machines, faucets and sinks. Inhaling or swallowing the bacteria is what causes the disease. It can also be found in lakes and streams, especially stagnant water. People that have an increased risk (immunocompromised) may need to avoid situations where there is an increased risk of legionellosis. (Freije, 2013 & Lane, Ferrari, & Dreher, 2004)
Urine antigen testing (most common method of detection) Culture of the organism Direct fluorescent antibody staining Serology (antibody titers) Both urine antigen testing AND culture of the organism are preferred by the CDC for diagnosis. (Lane, Ferrari, & Dreher, 2004)
PHARMACOLOGICALNON-PHARMACOLOGICAL * Azithrhromycin or levaquin- treatment of choice Erythromycin- not favorable Rifampin- in combination with macrolide or flurquinolone if pt is severely ill In an immunosuppressed pt: Treatment with Levaquin or Cipro for three weeks Antipyretics for fever Rest Deep breathing Symptomatic treatment Oxygen Hydration
Respiratory failure Dehydration Extrapulmonary disease Disseminated intravascular coagulation Multi orgal dysfunction Coma Death Follow up with a chest xray to ensure resolution. Respiratory status, hydration and electrolyte status should be assessed. Domino, 2014
Hot water tank temperature should be above 140°F. The temperature at the faucet should be above 122°F. Avoid conditions that allow water to stagnate. Tub baths may have less aerosolized bacteria then shower.
May need to collaborate with local public health officials to assess environmental risks, especially in areas such as apartment complexes. Silk, et al., 2013
Some highlights from the literature review were that Legionella is actually a fairly common cause of pneumonia, however it is very under-reported. There were difference in the first line treatment between literature. The 5-Minute Clinical Consult recommends levaquin as first line treatment but states that azithromycin may also be used as first line. In the article by Lane, Ferrari and Dreher, azithromycin is listed as first line. The Engineer’s Notebook discusses how new piping systems are not resistant to Legionella, some of the older systems are actually less prone to legionella growth due to less surface area in the piping.
1. True or False: Legionella can be identified using routine bacteriologic media? a.True b.False 2. Who is at most risk to develop Legionnaires’ disease? a.65 year old transplant recipient b.14 year old swimming in a lake c.90 year old living in an apartment complex 3. The preferred treatment for Legionnaires’ is ________. a.Erythomycin b.Rifampin c.Azithromycin
4. True or False: The CDC recommends urine antigen testing only for the diagnosis of Legionnaires disease? a.True b.False 5. Who should be tested for Legionnaires? a.In a person that has travelled in the last 2 weeks. b.Severe pneumonia c.A pt that has failed antibiotic therapy d.All of the above 6. NYS will most likely investigate cases of Legionella infection when: a.Someone is diagnosed with the condition b.A patient dies from the disease c.An outbreak is suspected
7. True or False: Legionnaires Disease should be reported to the Department of Health. a.True b.False 8. Complications of Legionnaires’ disease include: a.Fevers b.Respiratory failure c.Death d.All of the above 9. True or false: Legionella infection can be transmitted person to person. a.True b.False 10. Domestic water heaters should be kept at temperatures: a.Below 140 degrees F b.Above 140 degrees F
1. b. False- Specialized media like buffered charcoal yeast extract must be used. 2. a. Transplant recipients are at a high risk for LD due to anti-rejection medications. 3. c. Azithromycin 4. b. False- Both culture and urine antigen testing is recommended by the CDC. 5. d. All of the above 6. c. When an outbreak is suspected 7. a. True 8. d. All of the above 9. b. False 10. a. Above 140 degrees F (60 degrees C)
Centers for Disease Control & Prevention. (2013). Legionnaires’ disease for clinicians. Retrieved from Domino, F. (2014). The 5-Minute Clinical Consult. (22 nd ed.) Philadelphia: Lippincott Williams & Wilkins. Freije, M.R. (2012). Legionella: Don’t assume. Engineer’s Notebook: ASHRAA Journal, 54 (10), Lane, G., Ferrari, A., & Dreher, H. (2004). Clinical practice. Legionnaire's disease: a current update. MEDSURG Nursing, 13(6), New York State Department of Health. (2004). Legionellosis (Legionnaires’ Disease). Retrieved from Pedrot-Betot, M.L., Stout, S.E. & Yu, V.L. (2013). Epidemiology and pathogenesis of Legionella infection. Retrieved from infection. Silk, B. J., Foltz, J. L., Ngamsnga, K., Brown, E., Muñoz, M., Hampton, L. M., &... Hicks, L. A. (2013). Legionnaires' disease case-finding algorithm, attack rates, and risk factors during a residential outbreak among older adults: an environmental and cohort study. BMC Infectious Diseases, 13(1), 1- 8.