ABSTRACT
Ten patients from a rehabilitation center were admitted to hospital with serious respiratory infections within ten weeks. An outbreak of Legionnaire's disease was suspected based on the epidemic and atypical manifestation of pneumonia and could be proven microbiologically. Pulmonary and extrapulmonary complications included respiratory failure, lung abscess, transitory renal impairment in five patients and acute renal failure requiring dialysis in one, tetraparesis caused by peripheral neuropathy and acute psychosis. Three patients died despite immediate institution of therapy with erythromycin. Legionella pneumophila serogroup 1 subtype Pontiac was isolated from a bronchial lavage sample of one patient and from the water supply of the rehabilitation center. Monoclonal antibody subtyping and restriction endonuclease analysis were performed on both environmental and patient isolates. Potable water was identified as the source of the outbreak based on identical patterns on restriction endonuclease analysis. Despite thermic and chemical disinfection with chlorination (up to 15 ppm) in the rehabilitation clinic, an eleventh case of Legionnaire's disease was detected 11 months later.
Subject(s)
Cross Infection/etiology , Disease Outbreaks , Legionella pneumophila , Legionnaires' Disease/etiology , Rehabilitation Centers , Water Microbiology , Acute Disease , Adult , Aged , Antibodies, Monoclonal , Bronchoalveolar Lavage Fluid/microbiology , Cause of Death , Chlorine , Cross Infection/complications , Cross Infection/diagnosis , Cross Infection/drug therapy , Cross Infection/epidemiology , Disinfection , Erythromycin/therapeutic use , Female , Humans , Legionella pneumophila/classification , Legionnaires' Disease/complications , Legionnaires' Disease/diagnosis , Legionnaires' Disease/drug therapy , Legionnaires' Disease/epidemiology , Male , Middle Aged , Prognosis , Serotyping/methods , Treatment OutcomeABSTRACT
A series of nosocomial Legionella infections in a rehabilitation center is reported. In a three months period a total of 10 pneumonias with 3 deaths occurred (8 patients, 1 companion, 1 staff member). Serologic analysis proved additional Legionella infections within the nursing staff. The warm-water system was proved to be the source of infection by isolating Legionella pneumophila serogroup 1 subtype Pontiac both in warm-water and patients samples. The air conditioning system could not be ruled out as another (secondary) route of exposure because of shortcomings in construction. Conclusions about prevention and the course of the disease are discussed and standards for warm-water and air conditioning systems are proposed.
