ABSTRACT
Aspergilli are increasingly important infections in immunocompromised patients (ICP). The available antifungals often cause discrepancies in laboratory determination of MICs and a correlation in therapy. An effort was made to compare in vitro techniques for testing of antifungals, viz. polyenes, imidazoles, 5-fluorocytosine, amorolfine; and screened a phytoproduct- himachalol (a sesquiterpene alcohol) from Cedrus deodara (Roxb.) Loud against A. fumigatus clinical isolates (24) by macrobroth two-fold seal dilution (TFSD), microbroth microtitre (MT) and disc diffusion (DD) techniques using various broth/agar media at varying periods of incubation. The best activity in terms of geometric mean (GM) (GM.MIC < 0.39 microgrmas ml-1) was obtained with SCZ in the broth by both MT or TFSD technique followed by ECZ (GM.MIC 0.39 micrograms ml-1) and ITZ (GM.MIC 0.39-0.8 micrograms ml-1) in RPMI-1640. Overall RPMI-1640 was found to be the most suitable growth medium for testing of azoles or amorolfine, and YNB for polyene and 5-FC. MT technique was the most sensitive quantitative, reproducible, rapid and economical compared to other techniques. The treatment of Swiss mice with himachalol (200 mg kg-1, po) once a day, for 7 days, provided 60% protection concomitantly with increased MST (15 days) against invasive aspergillosis. A combination of himachalol (200 mgkg-1) plus SCZ (5 mgkg-1) showed better regimen in the therapy evidenced by enhanced survival (80%) of mice significantly (p < 0.001) with prolonged MST (> 15 days) compared to control. The treatments also reduced cfu (mean log10) burden of A. fumigatus from kidney.