Candida Yeasts, Pathogens

Candida Albicans is a yeast found on and in virtually every human being. Normally harmless, this yeast can take advantage of reduced immune function, decimated GI flora, and certain drugs to become pathogenic. Pathogenic means it is an organism that can cause disease.

The science and medical reports referenced, excerpted and summarized on this web page make that point clear.

Candida yeasts come in numerous species and strains with different human frequency in different geographies. Each type of yeast has different virulence, resistance to treatments, and pathogenic characteristics.

Learn up on yeast, and stay away from the sugar!


 "Antifungal therapy in the management of chronic candidiasis"; Benson J. Horowitz, MD; Dept. of Obstetrics and Gynecology, Mt Sinai Hospital, 449 Farmington Ave., Hartford, CT 06105

"Nine candida species are commonly recognized as being pathogenic in humans (Table 1). In an attempt to identify the same species that have been reported in the literature, we developed a reliable culture technique and then obtained vaginal samples from 175 consecutive patients. Our results were similar to those reported by others: among our first 175 patients, 65% were infected with Candida albicans and 23% with C. tropicalis. Only one patient had an infetion due to C. glabrata, a species more commonly seen in England than in the United States. Interestingly, three cases of infection were caused by the Saccharomyces cerevisiae - brewers or bakers yeast - were identified, as were six cases attributed to dermatophytes.

Another important finding was that not all yeast species react in the same way to imidazole preparations. C. tropicallis and C. glabrata, for example, are more resistant than C. albicans. In addition, a tenfold dose increase is necessary with drugs such as nystatin and miconazole to eliminate C. tropicallis and C. glabrata when compared with c. albicans in vitro. It should be pointed out that these results reflect only species differences; strain differences remain to be investigated."

Table I. Candida Species commonly found in human disease
C. albicans
C. guilliermondii
C. krusei
C. C. parapsilosis
C. stellatoidea
C. tropicallis
C. glabrata
C. psuedotropicallis
C. viswanathii


imidazole compounds (systemic yeast killers)
clotrimazole
miconazole
econazole
ketoconazole
butoconazaole

"C. tropicalis lacks ergosterol in its cell wall, and thus will not be killed by drugs designed to interfere with ergosterol synthesis......One exception to this principle is butoconazole. This agent's spectrum of activity includes the C. tropicalis organism"



"Candida infection in the tongue and pharnyx"; J Laryngol Otol; 98:6; 1984 June; 609-11; A. Bassiouny; HA el-refai; EA Abdel Nabi; AM Fateen; DS Hendawy.

"60 patients with chronic pharyngitis were investigated. In all cases the tongue was coated, fissured or hairy. Scrapings from the tongue and swabs from the posteriors pharyngeal wall were examined for the presence of Candida albicans. In the tongue, cultures were positive in all cases, and in the pharynx they were positive in 42 cases. After treatment with "Cansten" solution, the condition was cured in 53 cases. This directs attention to the role of Candida albicans as a cause of chronic pharyngitis, and to the relationship between candidiasis of the tongue and that of the throat."

"...many patients present with slight discomfort or considerable soreness in the throat. On examination the pharynx shows variable degrees of congestion. Usually the condition does not respond to antibiotics; indeed, it may be aggravated by the use of antibiotics, antiseptic lozenges, or gargles. The tongue in these cases looks unhealthy. It may show discolouration, deep fissures with elevated edges, shallow grooves or hypertrophied papillae. These observations directed our attention to the possibility that pathogenic fungi may affect the tongue and pharnyx, thus causing this picture."

"Ransome, in 1979, has also stated that Candida infection of the buccal and pharyngeal mucosa may be symptom less, or that it may only give slight discomfort or considerable soreness. Oral candidiasis can serve as a focus of infection from which the fungus spreads to the oropharnyx, hypopharnyx, and esophagus.

From our own results, it is obvious that candida infection of the pharnyx and tongue can occur in middle age and in non-debilitated persons. It causes variable degrees of soreness in the pharynx, but in the tongue it is symptom less in most cases, both tongue and pharnyx were were affected; this can be explained by direct continuity of the mucosa. Candidiasis of the tongue presented with different clinical pictures, e.g. coated tongue, hairy tongue, et.. In the pharynx, the characteristic candida rash did not show except in 5 percent of our cases."



"Gastrointestinal colonization and systemic dissemination by Candida albicans and Candida tropicallis in intact and immunocompromised mice."; Infec Immun; 60:11, 1992 Nov; 4907-14; de Repentigny L; Phaneuf M; Mathieu LG; Department of Microbiology and Immunology, Faculty of Medicine, University of Montreal, Quebec, Canada.

"Gastrointestinal colonization and systemic dissemination by Candida albicans and candida Tropicallis were compared in intact and immunocompromised mice. Five day old CFW mice were inoculated by the oral intragastric route with 1.0 X 10(7) CFU of two C. albicans and C. tropicallis strains isolated from the blood of patients with acute leukemia and with C. albicans 4918 and its cerulenin resistant mutant 4918-10. C. albicans and S. tropicallis spread to the lungs, liver, and kidneys within 30 minutes post inoculation, and organ CFU of the two species were comparable over the following 10 days. close association of blastocnidia with the villous surface of the small intestine resulted in lysis of microvilli and then the progressive invasion of villi. blastoconidia within the villi were surrounded by a conspicuous zone of clearing. Persistent colonization of the small and large intestines by C. albicans blood isolates and stains 4918 and 4918-10 was similar for 31 days after inoculation, but consistently exceeded that of C. tropicallis. In mice colonized with C. albicans, immunosuppression with cortisone acetate and cyclophosphamide on days 30 and 33 after inoculation increased stomach CFU 40 to 370 fold and intestinal 30 to 80 fold. In contrast, persistent colonization by C. tropicallis was undetectable before immunosuppression, and only became apparent after treatment. C. albicans disseminated more frequently and with higher organ CFU than C. tropicalis. Despite this fact, 20% of mice infected with c. tropicalis died, compared with 4% infected with C. albicans blood isolates. Indirect immunofluoresence revealed penetrative growth by Candida hyphae exclusively in the mucosa and submucosa of the stomach from immunosuppressed, persistently colonized mice. Taken together, the data indicate that C. tropicalis appears to be more virulent than C. albicans and that factors responsible for gastrointestinal colonization, systemic dissemination, and mortality in immunocompromised mice may not be identical."

Observations
1. The decreased weight gain of mice colonized with C. albicans may result from competition or malabsorption of nutrients.
2. The absence of systemic spread of both Candida species in persistently colonized mice before immunosuppression demonstrates that the normal GI tract and host defense mechanisms effectively prevent invasion by Candida species.



"Cutaneous manifestations of candidiasis"; Am J Obstetric Gynecology; 158:4; 991-993; April 1988; M McKay, MD; Atlanta, GA.

"Candida is identified microscopically by the observation of huffy, linear chains of asexually budding yeast. Since these structures do not grow extensively through the stratum corneum, cutaneous samples may require Gram stain for identification. since Candida can colonize normal tissue and also be a culture contaminant, clinicians should consider predisposing factors and clinical presentation when making a diagnosis of candidiasis. Predisposing cutaneous factors for candidiasis include occlusion, maceration, and altered barrier function. The hallmarks of Candida infection are bright erythema, fragile papulopustules, and satellite lesions. Cutaneous and mucous membrane candidiasis may differ in appearance, and sexual transmission should be considered. Treatment usually involves a topical or oral anticandidal agent, such as an imidazole. Although implicated as a predisposing factor to candidiasis, mild topical steroids can be used as short term adjuvant treatment of these infections; when used responsibly, steroids provide antiinflammatory effects that speed relief of patient discomfort."

Fact Review
1.Factors that predispose a patient to candidiasis...general health concerns include all conditions that affect the immune system, including systemic disease, endocrine abnormalities, diabetes, drugs such as immunosuppressive agents, systemic steroids, antibiotics, and oral contraceptives may increase the likelihood of development of candidiasis. Long term antibiotic treatment for acne or recurrent urinary tract infection is often implicated in the overgrowth of Candida.
2. The candidiasis may become extensive if the patients are treated with antibiotics on the erroneous assumption that the infection is bacterial.



"Mycology of vulvovaginitis"; Am J Obstet Gynecol; April 1988; 158:4; 989-990; WH Robertson, MD; Birmingham, Alabama.

"The life cycle of the yeast Candida is characterized by rapid budding, maturation, and degeneration. Pathogenic species and strain differences are identified and these differences are important in the study of recurrent infections. The relationships between Candida and other fungi, and between Candida and hormones, are discussed."

"The budding process occurs when the mother blastosphere produces a new cell outgrowth from a small site near one of the poles. The new bud enlarges until it is essentially as large as the parent. Mitosis occurs, the mother and daughter are partitioned by a septum, and each is now free to establish another cycle of budding"

"According to Odds the postulates of Koch have been unequivocally demonstrated for the following Candida species: c. albicans, C. tropicalis, C. stellatoidea, C. parapsilosis, C. psuedotropicalis, C. viswanathii.

They have been largely satisfied for the species C. guilliermondii, C. krusei, and C. glabrata. Other Candida species are also thought to be pathogenic.

The clinical significance of the various species is variable, with indicies of specific species varying according to the study. However, Odds quotes an overall frequency in isolates of 58% for C. albicans, 21% for C. glabrata, and 6% for C. tropicalis."

"There appear to be symbiotic relationships between some fungi and bacteria. A number of investigators have reported that Escherichia coli (E. coli), Salmonella, and Psuedomonas have an inhibitory effect on C. albicans. On the other hand, C. albicans demonstrates an inhibitory effect on Neisseria gonorrhea.

Carlson has studied the relationship between Staphylococcus aureus and C. albicans. Neither a sublethal dose of a toxin producing strain of Staphylococcus nor a comparable dose of Candida produced any results when infected into mouse peritoneal cavities. When the two were administered simultaneously, all of the mice died and at necropsy were found to have multiple microabsesses composed of a colony of S. aureas surrounded by a circumferential umbrella of C. albicans."


Back to Main Page



Copyright ©1996 / 1997 Jeff Clark