Neumonía aguda grave de la comunidad en menores de 65 a？os sin comorbilidades conocidas previamente: estudio multicéntrico retrospectivo

aims: to analyze epidemiologic, clinical and other abnormalities in healthy young adults with severe community acquired pneumonia (scap). methods: retrospective analysis of clinical records of adults younger than 65 years, with scap and without previously known comorbidities, admitted from 1998 to 2008. results: forty patients were included (m/f = 0.48), age 37.8 ± 14.1 years (range 16 - 61). mechanical ventilation was used in 42.5% and vasopressors in 57.5% of patients. initial pao2/fio2 ratio was 203.6 ± 91.4 mmhg (50 - 366.7); frequent laboratory abnormalities included: anemia, leukocytosis, hypoalbuminemia and high urea and creatinine levels. the empiric antimicrobial therapy was ceftriaxone or ？-lactam/？ - lactamases (bl) inhibitor plus macrolide in 70% of cases. the etiology was established in 50%; the specific pathogens were: streptococcus pneumoniae, 35%; leptospira, 15%; hantavirus and mycoplasma pneumoniae, 10%; and legionella pneumophila, pneumocystis jirovecii, histoplasma capsulatum, klebsiella pneumoniae, haemophilus influenzae bl (-) and methicillin susceptible staphylococcus aureus, 5%. complications were present in 77.5% including shock, respiratory failure, acute renal failure and pleural effusion. eight patients presented previously unknown comorbidities including hiv infection, diabetes mellitus, asthma, congestive cardiac failure and hypothyroidism. mortality was 12.5 %. diastolic arterial hypotension, taquichycardia, requirement of hemodialysis and inadequate therapy were significantly associated to mortality. conclusions: 20% of young and presumably healthy adults with scap had comorbidities. s. pneumoniae was the commonest pathogen; mortality was associated with severity of sepsis and inadequate therapy.