. 2026 May 22;64(6):e01324-25. doi: 10.1128/jcm.01324-25

TABLE 2.

Species identifications of Corynebacterium diphtheriae species complex bacteria samples by MALDI-TOF MS using the commercial Bruker database MBT_K^c^,^d

Species/parameter of interest	No. of samples	Score mean	Score STD	No. of samples identified	Identification rate (%)	No. of true positive	No. of false negative	True positive rate (%) of identified samples	False negative rate (%) of identified samples	No. of. samples of the control group	No. of samples identified	Identification rate (%)	No. of true negative	No. of false positive	True negative rate (%) of identified samples	False positive rate (%) of identified samples	Criteria of the BVL guideline fulfilled
C. diphtheriae s.l.
C. belfantii	7	2.19	0.09	7	100	0	7^a	0	100^a	1,602	803	50.1	803	0	100	0	No
C. diphtheriae s.s.	31	2.41	0.11	31	100	31	0	100	0	1,578	786	49.8	772	14^a	98.2	1.8^a	No
C. rouxii	8	2.12	0.11	7	87.5	0	7^a	0	100^a	1,601	803	50.2	803	0	100	0	No
C. diphtheriae s.s., C. belfantii, C. rouxii interpreted as C. diphtheriae s.l.	46	2.33	0.16	45	97.8	45	0	100	0	1,563	772	49.4	772	0	100	0	Yes^a
C. pseudotuberculosis	80	2.36	0.17	80	100	80	0	100	0	1,529	723	47.3	723	0	100	0	Yes
C. ulcerans s.l.
C. silvaticum	88	2.10	0.10	78	88.6	0	78^b	0	78^b	1,521	803	52.8	803	0	100	0	No
C. ramonii	9	2.37	0.09	9	100	0	9	0	100^b	1,600	803	50.2	803	0	100	0	No
C. ulcerans s.s.	105	2.37	0.10	105	100	105	0	200	0	1,504	785	52.2	698	87^a	88.9	11.1^b	No
C. ulcerans. s., C. ramonii, C. silvaticum interpreted as C. ulcerans s.l.	202	2.25	0.17	202	100	202	0	100	0	1,485	698	46.7	698	0	100	0	Yes^b

^{^a}

C. belfantii and C. rouxii are not represented in the database used.

^{^b}

C. ramonii and C. silvaticum are not represented in the database used. s.l.: sensu lato; s.s.: sensu stricto, No.: number; Score STD: standard deviation of the score.

^{^c}

True/False: the species was correctly/not correctly identified. All samples within the control group did not belong to the parameter of interest. Individual results for every sample are given in Tables S3a through i.

^{^d}

Italics indicate calulated values, like %, mean STD, against the counted numbers (roman).