Özlem GÜZEL, Esin ŞENOL, Ayşe KALKANCI, Semra KUŞTİMUR

In vitro activities of voriconazole, amphotericin B, and fluconazole against Candida strains isolated from neutropenic patients with haematologic malignancies

Amaç: Mantar infeksiyonlarının görülme sıklığının son 20 yılda artması ile antifungallere direnç gelişimi arasında son 20 yılda belirgin bir paralellik bulunmaktadır. Yeni azollerden vorikonazol (UK-109,496; Vfend (Pfizer Pharmaceuticals, New York)) henüz duyarlılık sınırları standardize edilmemiş triazol grubu bir antifungaldir. Yöntem: Bu çalışmada, vorikonazol, amfoterisin B ve flukonazolün NCCLS (Clinical Laboratory Standards Institution-CLSI) M27-A2 sıvı dilüsyon protokolüne uygun olarak minimal inhibitör konsantrasyonları belirlenmiştir. Sonuçlar: Klinik örnekler 52 adet Candida albicans, 20 adet C. glabrata, 18 adet C. kefyr, 13 adet C. tropicalis, üç adet C. parapsilosis, bir adet C. krusei, bir adet C. famata ve iki adet referans suş olmak üzere toplam 109 Candida suşundan oluşmaktadır. Bütün test edilen klinik örnekler ile vorikonazol için 0.007-2 mg/ml arasında MİK değerleri elde edilmiştir. Vorikonazol hem C. krusei hem C. glabrata’ya flukonazolün aksine etkili bulunmuştur. Test edilen 111 Candida suşundan 19 tanesi (%17.1) 64 mg/ml MİK değerleri ile flukonazöle dirençli bulunurken, 16-32 mg/ml Mİk değeri elde edilen 15 tanesi (%13.5) flukonazole doza bağlı duyarlı, 8 mg/ml MİK değeri elde edilen 64 tanesi (%57.6) flukonazole duyarlı bulunmuştur. C. tropicalis izolatlarından flukonazole beklenmedik bir şekilde 0.25-128 mg/ml aralığında yüksek MİK değerleri elde edilmiştir. Amfoterisin B MIC 50 değeri 0.0313 mg/ml bulunmuştur. Sonuç: Hastanemizde flukonazol direncinin artmakta olduğu buna karşılık amfoterisin ve vorikonazolün etkin olduğu bulunmuştur.

Hematolojik malignitesi olan nötropenik hastalardan izole edilen Candida suşlarına karşı vorikonazol, amfoterisin B ve flukonazolün in vitro etkinliği

Objective: The incidence of invasive fungal infections has increased in the last 20 years, which also have witnessed an increased resistance to established antifungal agents. Among the new azoles, voriconazole (UK-109,496; Vfend (Pfizer Pharmaceuticals, New York)) is a new triazole that does not have proposed standard procedures for antifungal susceptibility testing. Methods: We determined minimal inhibitor concentrations of voriconazole, amphotericin B, and fluconazole by following the NCCLS (Clinical Laboratory Standards Institution-CLSI) M27-A2 broth microdilution method. Results: A total of 109 clinical Candida isolates, including isolates of Candida albicans (n: 53), C. glabrata (n: 20), C. kefyr (n: 18), C. tropicalis (n: 13), C. parapsilosis (n: 3), C. krusei (n: 1), C. famata (n: 1), and two reference strains were included in our study. All the tested isolates were inhibited by voriconazole at concentrations ranging from 0.007 to m2 g/ml. Voriconazole had consistent and significant activity against isolates of both C. krusei and C. glabrata, as opposed to fluconazole. We found that 17.1% (n: 19) of the 111 Candida strains were resistant to fluconazole, with MIC values (equal or) higher than 64 g/ml; while 13.5% (n:15) of the 111 Candida strains were dose dependentsusceptible, with MIC values between 16 and 32 mg/ml; and 57.6% (n: 64) of them were susceptible, with MIC values under 8 mg/ml. C. tropicalis isolates surprisingly showed high fluconazole MIC values ranging from 0.25 to 128 mg/ ml. MIC50 of amphotericin B was 0.0313 mg/ml for all species tested. Conclusion: Fluconazole resistance is gaining importance in our institution while amphotericin B and voriconazole are still completely active.

PDF

___

1. Serrano MC, Ramírez M, Morilla D, Valverde A, Chávez M, Espinel- Ingroff A, Claro R, Fernandez A, Almeida C, Martin-Mazuelos E. A comparative study of the disc diffusion method with the broth microdilution and E test methods for voriconazole susceptibility testing of Aspergillus spp. J Antimicrob Chemother 2004; 53: 739-742.
2. Perfect JR, Marr KA, Walsh J, Greenberg RN, Dupont B, Torre- Cisneros JT, Just-Nubling G, Schlamm HT, Lutsar I, Espinel-Ingroff A, Johnson E. Voriconazole treatment for less-common emerging, or refractory fungal infections. Clin Infect Dis 2003; 36: 1122-1131.
3. National Committee for Clinical Laboratory Standards. Reference method for broth dilution antifungal susceptibility testing of yeasts; approved Standard, document M27-A. National Committee for Clinical Laboratory Standards, Wayne, Pa. 1998.
4. National Committee for Clinical Laboratory Standards. Reference method for broth dilution antifungal susceptibility testing of yeasts; approved Standard. Second edition, document M27-A2. National Committee for Clinical Laboratory Standards, Wayne, Pa. 2002.
5. Linares MJ, Charriel G, Solís F, Casal M. Comparison of two microdilution methods for testing susceptibility of Candida spp. to voriconazole. J Clin Microbiol 2004; 42: 899-902.
6. Rex JH, Pfaller MA, Galgiani JN, Bartlett MS, Espinel-Ingroff A, Ghannoum MA, Lancaster M, Odds FC, Rinaldi MG, Walsh TJ, Barry AL. Development of interpretive breakpoints for antifungal susceptibility testing: conceptual framework and analysis of in vitroin vivo correlation data for fluconazole and itraconazole and Candida infections. Subcommittee on antifungal susceptibility testing of the National Committee for Clinical Laboratory Standards. Clin Infect Dis 1997; 24: 235-247.
7. Marangon FB, Miller D, Giaconi JA, Alfonso EC. In vitro investigation of voriconazole susceptibility for keratitis and endophthalmitis fungal pathogens. Am J Ophthalmol 2004; 137: 820-25.
8. Conton E, Peman J, Carrillo-Munoz A, Orero A, Ubeda V, Vides A, Gobernado M. Fluconazole susceptibilities of bloodstream Candida spp isolates as determined by NCCLS method M27-A and two other methods. J Clin Microbiol 1999; 37: 2197-2200.
9. Cuenca-Estrella M, Rodriguez D, Almirante B, Morgan J, Planes AM, Almela M, Mensa J, Sanchez F, Ayats J, Gimenez M, Salvado M, Warnock DW, Pahissa A, Rodriguez-Tudela JL, Barcelona Candidemia Project Study Group. In vitro susceptibilities of bloodstream isolates of Candida spp to six antifungal agents: results from a population-based active surveillance programme, Barcelona, Spain, 2002- 2003. J Antimicrob Chemother 2004; 54: 1-6.
10. Peman J, Conton E, Gobernado M, and the Spanish ECMM working group on candidaemia. Epidemiology and antifungal susceptibility of Candida species isolated from blood: result of a 2-year multicentre study in Spain. Eur J Clin Microbiol Infect Dis 2005; 24: 1267-1269.
11. Pfaller MA, Messer SA, Boyken L, Tendolkar S, Hollis RJ, Diekema DJ. Variation in susceptibility of bloodstream isolates of Candida glabrata to fluconazole according to patient age and geographic location. J Clin Microbiol 2003; 41: 2176-2179.
12. Belanger P, Nast CC, Fratti R, Sanati H, Ghannoum MA. Voriconazole (UK-109,496) inhibits the growth and alters the morphology of fluconazole-susceptible and -resistant Candida species. Antimicrob Agents Chemother 1997; 41: 1840-1842.
13. Pfaller MA, Diekema DJ, Jones RN, Sader HS, Fluıt AC, Hollis RJ, Messer SA, SENTRY Participant Group. International surveillance of bloodstream infections due to Candida species: frequency of occurrence and in vitro susceptibilities to fluconazole, ravuconazole, and voriconazole of isolates collected from 1997 through 1999 in SENTRY antimicrobial surveillance program. J Clin Mıcrobiol 2001; 39: 3254-3259.
14. Barry AL, Brown SD. In vitro studies two triazole antifungal agents (voriconazole UK-109,496) and fluconazole against Candida species. Antimicrob Agents Chemother 1996; 40: 1948-1949.
15. Marco F, Pfaller MA, Messer S, Jones RN. In vitro activities of voriconazole (UK-109,496) and four other antifungal agents against 394 clinical isolates of Candida spp. Antimicrob Agents Chemother 1998; 42: 161-63.
16. Pfaller MA, Barry A, Bile J, Brown S, Ellis D, Meis JF, Rennie R, Rinaldi M, Rogers T, Traczewski. Quality control limits for voriconazole disk susceptibility tests on Mueller-Hinton agar with glucose and methylene blue. J Clin Microbiol 2004; 42: 1716-1718.
17. Lozano-Chiu M, Arikan S, Paetznick VL, Anaissie EJ, Rex JH. Optimizing voriconazole susceptibility testing of Candida: effects of incubation time, endpoint rule, species of Candida, and level of fluconazole susceptibility. J Clin Microbiol 1999; 37: 2755-59.
18. Chryssanthou E, Cuenca-Estrella M. Comparison of the antifungal susceptiblity testing subcommittee of the European committee on antibiotic susceptibility testing proposed standard and the E-test with the NCCLS broth microdilution method for voriconazole and caspofungin susceptibility testing of yeast species. J Clin Microbiol 2002;40: 3841-3844.
19. McGinnis M, Pasarell L, Sutton DA, Fothergill AW, Cooper CR, Rinaldi MG. In vitro evaluation of voriconazole against some clinically important fungi. Antimicrob Agents Chemother 1997; 41:1832-1834.
20. Sheehan DJ, Hitchcock CA, Sibley CM. Current and emerging azole antifungal agents. Clin Microbiol Rev 1999; 12: 40-79.
21. Arikan S, Ostrosky-Zeicherner L, Lozano-Chiu M, Paetznick V, Gordon D, Wallace T, Rex JH. In vitro activity of nystatin compared with those of liposomal nystatin, amphotericin B and fluconazole against clinical Candida isolates. J Clin Microbiol 2002; 40: 1406-1412.
22. Rex JH, Pfaller MA, Walsh TJ, Chaturvedi V, Espinel-Ingroff A, Ghannoum MA, Gosey LL, Odds FC, Rinaldi MG, Sheehan DJ, Warnock DW. Antifungal susceptibility testing: practical aspects and current challenges. Clin Microbiol Rev 2001; 14: 643-658.
23. Barry AL, Pfaller MA, Brown SD, Espinel-Ingroff A, Ghannoum MA, Knapp C, Rennie RP, Rex JH, Rinaldi MG. Quality control limits for broth microdilution susceptibility tests of ten antifungal agents. J Clin Microbiol 2000; 38: 3457-3459.
24. Pfaller MA, Messer SA, Hollis RJ, Jones RN, Diekema DJ. In vitro activities of ravuconazole, and voriconazole compared with those of four approved systemic antifungal agents against 6,970 clinical isolates of Candida spp. Antimicrob Agents Chemother 2002; 46:1723-1727.
25. Arikan S, Arslan S, Hascelik G, Gunalp A. In vitro susceptibility patterns of bloodstream yeast isolates to various antifungal agents in Hacettepe University Hospital. Mikrobiyol Bul 2001; 35: 433-441. 26. Coskun O, Besirbellioglu AB, Yildiran ST, Gonlum A, Pahsa A. In vitro susceptibilities of Candida species isolated from candidemic patients against amphotericin B and fluconazol. Mikrobiyol Bul 2001; 356: 565-571.