PneumoniaPneumonia, BacterialPneumonia, ViralPneumonia, PneumococcalCryptogenic Organizing PneumoniaPneumonia, PneumocystisPneumonia, StaphylococcalPneumonia, Ventilator-AssociatedPneumonia, AspirationCommunity-Acquired InfectionsPneumonia, MycoplasmaPneumonia, LipidLung Diseases, InterstitialLungIdiopathic Interstitial PneumoniasStreptococcus pneumoniaeAnti-Bacterial AgentsMurine pneumonia virusPneumocystis jiroveciiPneumocystisLegionnaires' DiseaseBronchoalveolar Lavage FluidRadiography, ThoracicMycoplasma pneumoniaeCross InfectionPulmonary EosinophiliaTrimethoprim-Sulfamethoxazole CombinationBronchopneumoniaHospitalizationPneumonia, Progressive Interstitial, of SheepRetrospective StudiesVentilators, MechanicalBronchoalveolar LavageRespiration, ArtificialProspective StudiesIntensive Care UnitsTreatment OutcomeFatal OutcomePneumonia of Swine, MycoplasmalPseudomonas InfectionsPneumococcal VaccinesAnti-Infective AgentsRisk FactorsSeverity of Illness IndexPneumocystis cariniiEmpyemaLegionella pneumophilaInfluenza, HumanPneumococcal InfectionsImmunocompromised HostLegionellaChild, HospitalizedBronchoscopyPentamidineChlamydial PneumoniaBacteremiaAIDS-Related Opportunistic InfectionsRespiratory Tract InfectionsPasteurellosis, PneumonicPulmonary FibrosisSputumIncidenceTime FactorsKlebsiella InfectionsAcute DiseasePseudomonas aeruginosaKlebsiella pneumoniaeOpportunistic InfectionsHaemophilus InfectionsLung DiseasesInfant, NewbornTomography, X-Ray ComputedPneumovirus InfectionsPneumocystis InfectionsCohort StudiesLength of StayLung AbscessSensitivity and SpecificityDisease Models, AnimalSepsisPasteurella InfectionsRespiratory InsufficiencyUnited StatesChlamydophila pneumoniaeConfusionIdiopathic Pulmonary FibrosisPneumonia, RickettsialNasopharynxPulmonary AlveoliPleural EffusionInfluenza A Virus, H1N1 SubtypeMycoplasma InfectionsHospital MortalityMacrophages, AlveolarMineral OilIntensive CareIntubation, IntratrachealLung Diseases, FungalMacrolidesDeglutition Disorders