TABLE 1.

Reactivities of Western blot-positive pediatric sera with the Pgp3 ELISA and commercial serological assays

Sample no.a	Result by the:
	Pgp3 assay (absorbance at 450 nm)	Medac pELISAb (AU/ml)	SeroCT ELISAc (COI)	Ani Labsystems EIAd (S/CO)
1	2.49	10.6	3.89	ND
2	1.92	54.7	2.06	2.40
3	2.01	313.9	4.08	4.36
4	1.70	90.5	3.30	3.70
5	2.59	145.6	5.02	4.52
6	2.46	67.4	2.88	2.31
7	2.18	48.7	1.57	2.00

^aAll seven samples were positive for C. trachomatis and C. pneumoniae by MIF at a dilution of 1:32.

^bResults were considered negative at ≤28 AU/ml and positive at >28 AU/ml.

^cCOI, cutoff index. Results were considered negative at ≤1.1 and positive at >1.1.

^dS/CO, signal-to-cutoff ratio. Results were considered negative at ≤1.4 and positive at >1.4. ND, not determined (insufficient serum available).