Measurement ofAntibodies totheBorrelia burgdorferi Flagellum Improves Serodiagnosis inLymeDisease

(Bannwarth's syndrome), themostfrequent secondarystage manifestation ofLymedisease inEurope. Twohundred healthy individuals andpatients withaseptic meningitis, encephalitis, Guillain-Barre syndrome, andsyphilis served ascontrols. Theflagellum ELISAwas significantly moresensitive thanthesonic extract ELISA. Thediagnostic sensitivities wereincreased from41.1 to76.8%(P< 0.01) forIgGandfrom35.7 to67.9%(P< 0.05) forIgMdetection inserum. Theincrease in sensitivity wasmostpronounced inpatients withashort duration ofdisease (<20daysafter onset). The diagnostic specificity increased forIgGdetection butwasalmost unaltered forIgM.Theflagellum ELISAdid notimprove thediagnostic sensitivity ofmeasuring antibodies toborreliae inCSF,mostlikely owing tothelow level ofunspecific antibodies inCSFcompared withserum. Thecross-reactivity ofseraandCSFfrompatients withsyphilis decreased significantly. Theflagellum antigen ofB.burgdorferi shows nostrain variation, iseasy topurify insufficient quantity, andistherefore asuitable reference antigen forroutine serodiagnosis ofLyme disease.