Table 1. Nontyphoidal Salmonella isolates with clinically important resistance, by serotype and resistance category, United States, 2004–2012*.

Resistance category	Typhimurium, no. (%), n = 3,324	Enteritidis, no. (%), n = 3,501	Newport, no. (%), n = 2,175	Heidelberg, no. (%), n = 738	Other fully serotyped, no. (%), n = 9,265	Not fully serotyped, no. (%), n = 407	Total NTS, no. (%), n = 19,410
Cipro†	54 (1.6)	211 (6.0)	7 (0.3)	2 (0.3)	183 (2.0)	10 (2.5)	467 (2.4)
Cef/Amp‡	162 (4.9)	8 (0.2)	198 (9.1)	87 (11.8)	141 (1.5)	3 (0.7)	599 (3.1)
Amp-only§	750 (22.6)	90 (2.6)	25 (1.1)	94 (12.7)	274 (3.0)	21 (5.2)	1,254 (6.5)
Any of the above¶	966 (29.1)	309 (8.8)	230 (10.6)	183 (24.8)	598 (6.5)	34 (8.4)	2,320 (12.0)

*Total NTS isolates include isolates serotyped as Typhimurium, Enteritidis, Newport, and Heidelberg; isolates serotyped as other than these 4; and those not fully serotyped. Amp-only, resistant to ampicillin but susceptible to ceftriaxone and ciprofloxacin; Cef/Amp, resistant to ceftriaxone and ampicillin; Cipro, nonsusceptible to ciprofloxacin but susceptible to ceftriaxone; NTS, nontyphoidal Salmonella. Cipro, Cef/Amp, and Amp-only are mutually exclusive categories.
†Nonsusceptible to ciprofloxacin (MIC >0.12 μg/mL) but susceptible to ceftriaxone, with or without resistance to other agents.
‡Resistant to ceftriaxone (MIC ≥4 μg /mL) and ampicillin (MIC ≥32 μg /mL), with or without nonsusceptibility to ciprofloxacin or resistance to other agents; of the 599 ceftriaxone-resistant isolates, 38 (0.2% of all NTS isolates) were nonsusceptible to ciprofloxacin.
§Resistant to ampicillin but susceptible to ceftriaxone and ciprofloxacin, with or without resistance to other agents.
¶Nonsusceptible to ciprofloxacin, resistant to ceftriaxone, or resistant to ampicillin.