legionnaires disease


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A severe lung infection by Legionella pneumophila which may occur sporadically or in an epidemic with a mortality of up to 15%; depending on the population, Legionella spp cause 1­­–27% of community-acquired pneumonias; male:female ratio, 3:1
Epidemiology Most L pneumophila infections are associated with water supplies and ventilation systems; most epidemics occur during the summer with 0.5–5% attack rates; the only documented mode of spead is aerosol
Sources Plumbing, shower heads, water-storage tanks, evaporative condensors, cooling towers
Risk factors Cigarettes, alcohol, renal transplant, elderly
DiffDx Sporadic LD mimics myoplasma pneumonia, Q fever, tularemia, plague, psittacosis, influenza and other viral pneumonias
Lab Decreased Na+, decreased PO4-, increased liver enzymes, proteinuria, microscopic hematuria, relative leukocytosis, increased ESR, hyponatremia, increased ALT, increased AST, increased BR, azotemia
Complications Empyema, shock, DIC, renal failure, neurologic sequelae, peripheral neuropathy
Management Erythromycin, T-S, penicillin
Prognosis 15–20% mortality w/o therapy; up to 50% of immunocompromised patients die
Poor prognostic features Tachycardia, tachypnea, WBCs 14,000/mm3, increased BUN, increased creatinine, hyponatremia, hypoxia, leukopenia, bilateral infiltrates on chest films
Prevention Chlorination of water supply for showers and ventilation systems; UV irradiation of water supplies

legionnaires’ disease

a rare human pneumonial condition, caused by the bacterium Legionella pneumophila, that can lead to death. The disease was named after an outbreak occurring at an American Legion convention in a Philadelphia hotel in 1976, the bacteria eventually being traced to the air-conditioning plant of the hotel. Since then a number of cases have been reported in connection with recirculated hot water systems such as cooling towers. There is no evidence of person-to-person transmission.
References in periodicals archive ?
To identify potential exposures associated with Legionnaires disease, case-patients were asked about their activities during the 2 weeks before onset of illness.
Editorial Note: Approximately 10,000-15,000 cases of Legionnaires disease occur each year in the United States; most occur sporadically (1).
The number of cases of Legionnaires disease reported to the CDC rose from 436 in mid 2002 to 624 in mid 2003.
Public Health England (PHE) has seen a recent increase in the number of cases of Legionnaires disease in people who have travelled to a town called Palmanova, in Mallorca, Spain.
It was after the third diagnosis of Legionnaires Disease in March that the hospital decided to test their water for Legionella.
According to EWGLI, more than 700 cases of Legionnaires disease were reported in Europe in 2002, tripling the number of reported cases over the past decade.
Yesterday it was confirmed one man had Legionnaires Disease and there were 49 confirmed or probable cases of Pontiac Fever.
When only about fifty-nine people per year in California contract Legionnaires Disease, and nineteen of them happen to work in the Borax Building, we know there is a serious problem," remarked Brian Kabateck, founding partner of the law firm, Quisenberry & Kabateck LLP.
Officials at Harford Memorial Hospital reported today that final results of independent tests to determine the presence of bacteria that causes Legionnaires Disease show that the water supply at the hospital is clean and safe.