Chloroquine does not enhance the activity of clarithromycin against multiplication of Mycobacterium avium within human macrophages.
METHODS
Chloroquine, an alkalinizing lysosomotropic agent, enhances the intracellular activity of antibiotics against Mycobacterium tuberculosis or Coxiella burnetii.


OBJECTIVE
To determine if chloroquine modifies the activity of clarithromycin, less effective at acidic pH, against intracellular Mycobacterium avium.


METHODS
The activity of clarithromycin (4 micrograms/ml) against the MO-1 strain of M. avium was evaluated within human macrophages in presence of chloroquine (5 micrograms/ml). The minimal inhibitory concentration of clarithromycin for the strain was 2 micrograms/ml.


RESULTS
While clarithromycin alone did decrease the intracellular infection at day 7 of culture (P < 0.01), chloroquine alone did not impede the intracellular growth of M. avium, and did not enhance the activity of clarithromycin.


CONCLUSIONS
Chloroquine should not improve clarithromycin treatment against M. avium infection.
Lazard
T
T
Institut National de la Santé et de la Recherche Médicale, Hôpital Bichat-Claude Bernard, Paris.
Perronne
C
C
Truffot-Pernot
C
C
Grosset
J
J
Vildé
J L
JL
Pocidalo
J J
JJ
D002478:Cells, Cultured; D002738:Chloroquine / Q000494:pharmacology*; D017291:Clarithromycin / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004347:Drug Interactions; D006801:Humans; D008264:Macrophages / Q000382:microbiology*; D009162:Mycobacterium avium / Q000187:drug effects / Q000254:growth & development*
D002738:Chloroquine; D017291:Clarithromycin