C-Reactive ProteinComplement C3Complement C4Blood SedimentationComplement C4aComplement C3aComplement C1qComplement C5aComplement ActivationComplement C4bComplement C5Complement C3bComplement System ProteinsBiological MarkersComplement C6Complement C3cArthritis, RheumatoidComplement C3dComplement C2Complement C9Receptors, ComplementComplement C1sAcute-Phase ReactionComplement Membrane Attack ComplexComplement C1rSerum Amyloid A ProteinTuberculosis, MiliaryComplement Inactivator ProteinsComplement C7Complement C3-C5 ConvertasesSpondylitis, AnkylosingAntirheumatic AgentsNephelometry and TurbidimetryComplement Factor BComplement Pathway, AlternativeComplement Pathway, ClassicalComplement C8Gold Sodium ThiomalateLeukocyte CountPolyarteritis NodosaComplement C1Mendelian Randomization AnalysisRheumatoid FactorBacterial InfectionsOrosomucoidReceptors, Complement 3bProspective StudiesPolymyalgia RheumaticaComplement Factor HAcute DiseaseArthritis, PsoriaticComplement C5bComplement C2aSeverity of Illness IndexMeningitis, ViralStatistics, NonparametricSynovitisReceptor, Anaphylatoxin C5aLatex Fixation TestsCalcitoninComplement Activating EnzymesFeverCrohn DiseaseComplement Inactivating AgentsComplement Hemolytic Activity AssayImmunoglobulin GComplement C1 Inactivator ProteinsReceptors, Complement 3dEnzyme-Linked Immunosorbent AssayAnaphylatoxinsSynovial FluidInfant, Premature, DiseasesOsteoarthritisAcute-Phase ProteinsInterleukin-6ArthritisSepsisCase-Control StudiesTime FactorsComplement Fixation TestsInflammationInfant, NewbornAntibodies, MonoclonalComplement Factor DRisk FactorsAutoantibodiesPancreatitisComplement Factor IAngina, UnstablePrednisoloneTreatment OutcomePrognosisComplement C4b-Binding ProteinCross-Sectional StudiesComplement C3b Inactivator ProteinsTumor Necrosis Factor-alphaDouble-Blind MethodFalse Positive ReactionsInflammation MediatorsFollow-Up Studies