Table 6.

Summary of antibiotic(s) usage and the dose range in 37 cats infected with Rhodococcus equi

	Pre-diagnosis (antibiotic[s])	Post-diagnosis (antibiotic[s])	No. of cats (n = 37)	Outcome (n = 37)	Remarks
1	Amoxicillin–clavulanic acid	–	3	3 died	One owner refused boarding; 2 died in pre-diagnostic management
2	Amoxicillin–clavulanic acid	Azithromycin + rifampin	3	2 recovered, 1 died	Of 2 recovered cats, 1 went through a course of enrofloxacin + azithromycin before presentation. Other bacteria were susceptible to azithromycin, but infection relapsed after apparent recovery of this cat, possibly because of poor compliance, and the cat died 9 weeks after initial diagnosis because of a similar presentation
3	Marbofloxacin	–	2	1 recovered, 1 died	One cat died in pre-diagonstic management, while the other went through thoracotomy, and bacteria susceptible to marbofloxacin
4	Marbofloxacin	Azithromycin	1	1 died	Went through thoracotomy but died within 7 days of postoperative management of infection
5	–	Gentamicin + rifampin	1	1 euthanased	Owner refused post-diagnosis management
6	Marbofloxacin + metronidazole	–	3	3 died	Two cats died during pre-diagnostic management; third cat died during long-term (4 weeks) management post-diagnosis
7	Marbofloxacin + metronidazole	Switched to azithromycin + rifampin	1	1 recovered	Bacteria susceptible to azithromycin
8	Amoxicillin–clavulanic acid + metronidazole	Switched to azithromycin + rifampin	8	5 recovered, 2 died, 1 euthanased	Of the two cats that died, 1 was FeLV positive. Infection relapsed after an apparently full recovery in 1/5 recovered cats, possibly because of poor compliance, and the cat died 10 weeks after the initial diagnosis because of a similar presentation
9	Amoxicillin–clavulanic acid + metronidazole	Switched to marbofloxacin + rifampin	2	2 recovered	Bacteria was susceptible to marbofloxacin in both cases
10	Amoxicillin–clavulanic acid + metronidazole	–	4	4 died	All cats died during pre-diagnostic management of infection
11	Amoxicillin–clavulanic acid + azithromycin	Rifampin added and amoxicillin–clavulanic acid stopped	1	1 euthanased	Poor response to treatment during long-term management (4 weeks)
12	Amoxicillin–clavulanic acid + metronidazole + azithromycin	Rifampin added and amoxicillin–clavulanic acid and metronidazole stopped	2	1 recovered, 1 died	Dead cat had a high FCoV antibody titre and a low A:G (0.5), supporting clinical signs
13	Amoxicillin–clavulanic acid + marbofloxacin + azithromycin	Rifampin added and amoxicillin–clavulanic acid stopped	1	1 recovered	–
14	Amoxicillin–clavulanic acid + metronidazole + marbofloxacin	Rifampin added and amoxicillin–clavulanic acid and metronidazole stopped	2	1 recovered, 1 died	Poor response to antibiotics seen in the dead cat and bacteria were resistant to marbofloxacin
15	Amoxicillin–clavulanic acid + metronidazole + marbofloxacin	Switched to azithromycin and rifampin	1	1 euthanased	Poor response to antibiotics and chest tube management, although bacteria were susceptible to azithromycin
16	Amoxicillin–clavulanic acid + metronidazole + marbofloxacin	–	1	1 recovered	Eight weeks of therapy and bacteria were susceptible to marbofloxacin
17	Amoxicillin–clavulanic acid + metronidazole + enrofloxacin	–	1	1 died	Died during pre-diagnostic management

Amoxicillin–clavulanic acid: 12.5–20 mg/kg q12h; metronidazole: 10–15 mg/kg (lower dosage q8h and higher dosage q12h); marbofloxacin: 2–4 mg/kg q24h (higher dosage for susceptible bacteria); enrofloxacin: 5 mg/kg q24h for a maximum of 3 days; azithromycin: 10 mg/kg q24h used for a maximum of 8 weeks; rifampin: 10 mg/kg q24h used for a maximum of 8 weeks (with on and off adverse effects in three cases, such as anorexia and vomiting possibly related to hepatotoxicity)

FeLV = feline leukaemia virus; FCoV = feline coronavirus; A:G = albumin to globulin ratio