Table 1.

Additional β-lactam resistance mechanisms observed among 319 OXA-48-like-producing K. pneumoniae

Organisms/OMP alterations	No. of isolates among all K. pneumoniae	No. of isolates with acquired broad-spectrum β-lactamases
		ESBLs					MBLs	KPC-2	transferable AmpC ± ESBL	only OXA-48-like
		all ESBLs	CTX-M-14	CTX-M-15	CTX-M-15 + OXA-1	other ESBLs
All K. pneumoniae	319	241	9	57	156	19	36	1	4	37
OMP alterations
OmpK35 stop codon	212	152	6	44	92	10	25	1	2	32
all OmpK36 alterations	197	141	6	41	85	9	22		2	32
OmpK36 A183_T184insLSP	67	50		3	46	1	4		2	11
all OmpK36 G134_D135ins	130	91	6	38	39	8	18			21
OmpK36 G134_D135insD	18	3		3			15
OmpK36 G134_D135insDG	20	15	5	1	8	1	2			3
OmpK36 G134_D135insDG, A183_T184insLSP	88	70	1	32	31	6	1			17
OmpK36 G134_D135insDT, G182_A183insTS	2	2		2
OmpK36 stop codon	2	1				1				1
OmpK36 WT	15	11		3	7	1	3	1
OmpK35 WT	107	89	3	13	64	9	11		2	5
all OmpK36 alterations	76	64	1	10	50	3	8		2	2
OmpK36 A183_T184insLSP	44	39		5	31	3	1		2	2
all OmpK36 G134_D135ins	32	25	1	5	19		7
OmpK36 G134_D135insD	1	1	1
OmpK36 G134_D135insDG	23	16			16		7
OmpK36 G134_D135insDG, A183_T184insLSP	4	4		4
OmpK36 stop codon	4	4		1	3
OmpK36 WT	31	25	2	3	14	6	3			3