Quantitative PCR of ear discharge from Indigenous Australian children with acute otitis media with perforation supports a role for Alloiococcus otitidis as a secondary pathogen

Table 2 A. otitidis isolates cultured from ear discharge swabs

Sample	Days of culture until A. otitidis was isolated		Penicillin MIC	Erythromycin MIC	Azithromycin MIC
Sample	HBA agar	BHI agar with 6.5%NaCl	Penicillin MIC	Erythromycin MIC	Azithromycin MIC
Child A (Left ear)	5	7	0.19	4	1.5
Child A (Right ear)	2	5	0.125	3	2
Child B	14	5	0.006	>256	128
Child C	Not detected*	9	0.19	>256	>256
Child D	7	Not detected	0.032	96	64

Culture and antibiotic susceptibility data for five isolates from four children (designated child A-D). All cultures were positive for other bacteria after two days’ incubation. MIC values are in μg/mL. In the absence of A. otitidis-specific CLSI breakpoints, the MIC values used to define pneumococcal susceptibility were applied[28]. For oral penicillin V: sensitive ≤0.06μg/mL, intermediate susceptibility 0.12-1μg/mL, resistant ≥2μg/mL. For erythromycin: sensitive ≤0.25μg/mL, intermediate susceptibility 0.5μg/mL, resistant ≥1μg/mL. For azithromycin: sensitive ≤0.5μg/mL, intermediate susceptibility 1μg/mL, resistant ≥2μg/mL. HBA = Horse blood agar. *This plate was overgrown by a Proteus sp.

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