Anti-bacterial activity of intermittent preventive treatment of malaria in pregnancy: comparative in vitro study of sulphadoxine-pyrimethamine, mefloquine, and azithromycin

Table 1 Median minimal inhibitory concentrations (MIC) of anti-malarials against selected Gram-positive and Gram-negative bacteria.

Microorganisms	Median Minimal Inhibitory Concentration (μg/ml)
	Sulphadoxine/Pyrimethamine	Mefloquine	Azithromycin
S. aureus (n = 5)	16	16	0.5
S. agalactiae (n = 4)	24	16	0.06
S. pneumoniae (n = 5)	4	0.06	0.01
E. faecalis (n = 5)	12	16	4
N. gonorrhoeae (n = 10)	256	8	0.01
E. coli (n = 5)	128	128	4

Thresholds for drug resistance:
Mefloquine: sensitive: ≤ 0.265 μg/ml
Sulphadoxine/Pyrimethamine (threshold based on fractional pyrimethamine concentration in 1:20 combination): sensitive, intermediate, resistant
S. aureus and E. coli: ≤ 2 μg/ml; > 2 - < 4 μg/ml; ≥ 4 μg/ml,
S. pneumonia: ≤ 0.5 μg/ml; > 0.5 - < 4 μg/ml; ≥ 4 μg/ml,
S. agalactiae: ≤ 1 μg/ml; > 1 - ≤ 2 μg/ml; > 2 μg/ml,
E. faecalis: ˂ 0.03 μg/ml; ≥ 0.03 - ≤ 1 μg/ml; > 1 μg/ml.
Azithromycin: sensitive, intermediate, resistant
S. aureus; E. coli and E. faecalis ≤ 2 μg/ml, > 2 - < 8 μg/ml, ≥ 8 μg/ml;
S. pneumonia and S. agalactiae ≤ 0.5 μg/ml, > 0.5 - < 2 μg/ml, ≥ 2 μg/ml;
N. gonorrhoeae ≤ 0.25 μg/ml; > 0.25 μg/ml - ≤ 0.5 μg/ml; > 0.5 μg/ml;

ISSN: 1475-2875