Table 1.

Susceptibility phenotypes and resistance mechanisms in S. pneumoniae and H. influenzae and the inferred prevalence in Spain [36-43].

Phenotype	Penicillin	Ampicillin/ amoxicillin	Amoxicilin-clavulanate	Cefuroxime	Cefixime	Cefotaxime	Cefditoren	Imipenem /meropenem	Beta-lactamase	Altered PBPs	Prevalence
Streptococcus pneumoniae
Pen-S, CTX-S (Wild type)	S	S	S	S	S	S	S	S	-	-	80-90%
Pen-I/R, CTX-S	I/R	I	I	I/R	I/R	S	S	S	-	1A,2X,SB	5-10%
Pen-S, CTX-I/R	S	I	I	R	R	I/R	I/R	S	-	2x	<1%
Pen-I, CTX-I/R	I	I	I	I/R	R	I/R	I/R	S	-	1A,2X	<1%
Pen-R, CTX-I/R	R	R	R	R	R	I/R	I/R	I/R	-	1A,2X,SB	2-5%
Haemophillus influenzae
Wild Type	R	S	S	S	S	S	S	S	-		60-70%
BLPAR: β-lactamase-(+) ampicillin-resistant	R	R↑	S	S	S	S	S	S	TEM-1, ROB	-	20-30% (decreasing)
BLNAR: β-lactamase-(-) ampicillin-resistant	R	R↓	R↓	R	S↓	S	S	S	-	3	5-10% (increasing)
BLPACR: β-lactamase-(+) amoxicillin-clavulanate-resistant	R	R↑	R	R↓	S↓	S	S	S	TEM-1, ROB	3	<3% (increasing)

Arrows indicate low (R↓) and high level (R↑) resistance or decrease susceptibility (S↓).