Polmonite da legionella e compromissione neurologica

The incidence of Legionnaires' disease ranges between 2-13% of all community acquired pneumonia (CAP). Risk factors include advanced age, smoking, COPD, chronic renal failure in hemodialysis and immunodepression (cancer, diabetes, chronic use of corticosteroids, organ transplantation). This disease presents multisistemic extrapulmonary manifestations, in 40% of cases, we can find neurological signs and symptoms like torpidity, sleepiness, headache, while other typical clinical manifestations are myalgias, watery diarrhea (50% of cases), sinus bradycardia (60% of cases), abdominal discomfort, nausea and vomiting (25% of cases). In the literature associated with Legionnaires' disease, two neurological syndromes have been reported, with extremely wide patterns of severity. The first one is characterized by headache, confusion, and obtundiment for diffused cerebral involvement; in the second, more limited one tremors, ataxia, nystagmus, oculomotor muscles and visus paralysis, disartria prevail. Mortality ranges roughly between 10-13% and rarely exceeds 30% in severe cases, which need a UTIR recovery. Results depend on host immunocompetence, early start of an adequate therapy and on complications. The case here reported reminds that in patients with Legionella pneumophila the involvement infections must be considered of central nervous system. This involvement can precede or can be contemporary to pneumonia onset. Vigilance alterations are the most common symptom even if often associated with sometimes unusual signs of more localized damage. A causal relationship between this pathogen and the neurological syndrome is never been demonstrated: immunological reactions or neurotoxin action can be responsible for neurological alterations.