TABLE 4.

Evaluation of Western blot interpretation criteria for B. quintana endocarditis^a

Criterion(s) (bands required)	B. quintana infectionb		Bartonella sp. endocarditisc
	Sensitivity (%)	Specificity (%)	Sensitivity (%)	Specificity (%)	PPV (%)
≥1 of any B. quintana band and ≥2 of any B. henselae bands	97.0	90.9	97.0	33.3	81.8
≥7 of any B. quintana bands or no. of B. quintana bands ≥ no. of B. henselae bands + 2	81.1	100.0	81.1	100.0	100.0
≥1 of Bq83 and/or Bq10	100.0	100.0	100.0	83.3	94.9
≥3 of Bq83, Bq45, Bq35, Bq30, and/or Bq20	97.3	90.9	97.3	83.3	94.7

^aRecommended criteria are in boldface.

^bSensitivity and specificity of the various criteria were determined for all tested sera from patients with B. quintana infection (n = 48).

^cSensitivity, specificity, and PPV of the various criteria were determined for all tested sera from patients with Bartonella endocarditis (n = 49).