PneumoniaPneumonia, BacterialPneumonia, ViralPneumonia, PneumococcalCryptogenic Organizing PneumoniaPneumonia, PneumocystisPneumonia, StaphylococcalPneumonia, Ventilator-AssociatedPneumonia, AspirationCommunity-Acquired InfectionsPneumonia, MycoplasmaPneumonia, LipidLung Diseases, InterstitialDelayed DiagnosisSensitivity and SpecificityEarly DiagnosisPrenatal DiagnosisRetrospective StudiesLungAnti-Bacterial AgentsIdiopathic Interstitial PneumoniasProspective StudiesStreptococcus pneumoniaeRadiography, ThoracicDiagnosisTreatment OutcomePneumocystis jiroveciiTomography, X-Ray ComputedFatal OutcomeMurine pneumonia virusRisk FactorsPneumocystisBronchoalveolar Lavage FluidLegionnaires' DiseaseMycoplasma pneumoniaeBiopsyHospitalizationCross InfectionDiagnostic ErrorsTime FactorsInfant, NewbornPredictive Value of TestsSeverity of Illness IndexIncidenceTrimethoprim-Sulfamethoxazole CombinationPulmonary EosinophiliaBronchopneumoniaPrognosisBronchoalveolar LavageAcute DiseaseCohort StudiesDiagnosis, Computer-AssistedBronchoscopyIntensive Care UnitsPneumonia, Progressive Interstitial, of SheepRespiration, ArtificialFollow-Up StudiesPolymerase Chain ReactionVentilators, MechanicalReproducibility of ResultsSputumNursing DiagnosisImmunocompromised HostAge FactorsAIDS-Related Opportunistic InfectionsAnti-Infective AgentsEmpyemaUnited StatesPseudomonas InfectionsPneumonia of Swine, MycoplasmalRespiratory Tract InfectionsPneumococcal VaccinesCase-Control StudiesBiological MarkersInfluenza, HumanPneumocystis cariniiLung DiseasesPreimplantation DiagnosisLegionella pneumophilaPregnancyBacteremiaMagnetic Resonance ImagingComorbidityChild, HospitalizedPrevalenceBiopsy, NeedlePleural EffusionPneumococcal InfectionsLegionellaEnzyme-Linked Immunosorbent AssayOpportunistic InfectionsPulmonary FibrosisROC CurveLength of StayAutopsyPentamidineChlamydial PneumoniaPasteurellosis, PneumonicSepsisSyndrome