Candida Glabrata
Total Page:16
File Type:pdf, Size:1020Kb
Candida glabrata Sometimes a problem, sometimes not… andida glabrata, once Pathogenicity known as Torulopsis Infections are most commonly seen Cglabrata, is a common non- in the elderly, immuno- hyphae forming yeast isolate in the compromised, and AIDS patients. It clinical laboratory. It is a member, is most importantly known as an along with over 200 other species, agent of urinary tract infections. In of the Candida genus. fact, 20% of all urinary yeast infections are due to C. glabrata, Habitat although they may be asymptomatic Candida spp. are ubiquitous and left untreated. inhabitants of the gastrointestinal tracts of mammals. According to More serious infections would Jay Hardy, CLS, SM (ASCP) one study, in the human GI tract, the include rare cases of endocarditis, most commonly isolated species meningitis, and disseminated would be in the following order: infections (fungaemias). Jay Hardy is the founder and C. albicans It has the ability to form sticky CEO of Hardy Diagnostics. C. tropicalis “biofilms” that adhere to living and He began his career in C. parapsilosis non-living surfaces (such as microbiology as a Medical C. glabrata catheters) thus forming microbial Technologist in Santa mats, making treatment more Barbara, California. However, some references list it as difficult. the second most commonly isolated In 1980, he began Candida organism from GI sources. Recently a shift has been noted from manufacturing culture media fungal disease caused by C. for the local hospitals. C. glabrata can be routinely isolated albicans to that of non-albicans Today, Hardy Diagnostics is as a commensal from the following species of Candida, such as glabrata, the third largest media body sites: especially in ICU patients. manufacturer in the US. Oral cavity Laboratory Cultivation To ensure rapid and reliable Genitourinary tract C. glabrata grows readily on all turn around time, Hardy Alimentary tract ordinary culture media such as; maintains six distribution Respiratory tract Sabdex, Mycobiotic, Inhibitory centers, and produces over Mold, BHI, or Blood Agar. A 2,700 products used in distinguishing characteristic is its clinical and industrial relatively slow growth on culture microbiology laboratories media; often requiring 48 to 72 throughout the world. hours for well developed colonies. For this reason, urine cultures should be incubated no less than three days. Colony Morphology The colonies will appear as small glossy, convex, and smooth. The color will be white to cream on Sabouraud’s Dextrose Agar. On Hardy’s chromogenic media, glabrata possesses is low-level HardyCHROM Candida, (cat no. intrinsic resistance to the azole G301) the colonies will be pink to drugs, which are the most mauve in color, often with a darker commonly prescribed antifungal center. HardyCHROM Candida will drugs. These drugs, including easily provide a presumptive fluconazole and ketoconazole, identification, however other although effective against most C. species of yeast will have a similar albicans isolates, are quite useless appearance on this media. against C. glabrata. Confirmation testing must be performed using rapid trehalose, as C. glabrata cells as seen growing It is still highly susceptible to described below. on Corn Meal with Tween Agar. polyene drugs such as amphotericin Biochemical Identification B and nystatin, along with variable vulnerability to flucytosine and Identification caspofungin. For systemic Laboratory identification is infections, amphotericin B remains facilitated by the fact that C. the drug of choice in spite of its side glabrata will ferment glucose and effects that are of great concern. rapidly ferment trehalose, making it unique among the yeasts. Hardy Due to its intrinsic resistance to Diagnostics offers two products for fluconazole and related drugs, it is this purpose. very important that Candida C. glabrata colonies as seen on glabrata be accurately identified HardyCHROM Candida Agar. Rapid Trehalose Broth, cat. no. and reported as such to the attending Z205. With this rapid test, C. physician, so that appropriate glabrata will turn the broth from therapy can be initiated. Microscopic Morphology blue to yellow within three hours. Microscopically the cells of C. glabrata will appear as small sized yeast cells (2 to 3 microns in Jay Hardy, CLS, SM (ASCP) diameter) less than half the size of a Santa Maria, CA red blood cell. They are often seen with single budding, and do not form hyphae or pseudohyphae. The cells are often more spherical rather than elongated as with some other Candida species. C. glabrata will not produce germ tubes, as seen with C. albicans. GlabrataQuick, cat. no. Z298. This rapid test kit will test maltose and sucrose (which will be negative) in addition to trehalose, thus eliminating the chance of false positives. This test can be read out in only one to two hours. On Corn Meal Agar, C. glabrata cells will appear under the microscope in very closely packed groupings, without any separations Treatment and Susceptibility as with Cryptococcus spp. Unfortunately, a major phenotype and potential virulence factor that C. .