Course Outline
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- Introduction to Medically Important Fungi
- Introduction to Yeast, Molds, Thermally Dimorphic Fungi, and Safety Considerations
- Taxonomy
- Clinical Manifestations
- The taxonomy of fungi is constantly evolving. One such reason for this is:
- Yeast: Describe, Recognize, and Identify
- Yeast
- Introduction to Cryptococcus
- Cryptococcus Epidemiology
- Cryptococcal Infections
- Cryptococcus Identification
- All of the following special microbiology/histology stains are useful for the identification of Cryptococcus, except:
- Cryptococcus is commonly found in soil contaminated by bird droppings and decaying wood and in tree hollows.
- Candida species
- Candida glabrata
- Which feature distinguishes Candida glabrata from other infectious Candida species?
- Rhodotorula
- Rhodotorula species are yeasts that produce a pyocyanin pigment ranging from yellowish to red that can be visualized with individual colonies.
- Malassezia
- Which supplement is necessary to add to culture media to ensure proper growth of Malassezia species?
- Saccharomyces cerevisiae
- Trichosporon
- Trichosporon, continued
- Trichosporon yeasts form arthroconidia and hyphal elements that are larger than those of Candida species.
- Blastoschizomyces
- Pneumocystis: The "Yeast-like" Fungus
- Molds: Describe, Recognize, and Identify...
- Aspergillus
- Aspergillus
- Aspergillus, continued
- Aspergillus niger
- What is a distinguishing feature of Aspergillus species as seen in stains of tissues?
- Fusarium
- Fusarium
- What shape is commonly associated with the description of the macroconidia of Fusarium species?
- Dermatophytes
- Introduction to Dermatophytes
- Which enzymes do dermatophytes employ to digest hair, nails, and the stratum corneum of skin?
- Epidermophyton
- Epidermophyton floccosum always produces microconidia.
- Which antibiotic is used in growth media to help isolate dermatophytes?
- Trichophyton
- Trichophyton, continued
- Microsporum
- Microsporum, continued
- The dermatophytes consist of all of the following, except:
- Dematiaceous Molds
- Introduction to Dematiaceous Molds
- Dematiaceous Molds, continued
- Typically, dematiaceous molds are darkly pigmented on both the surface and reverse side of the culture plate.
- Which is a feature that can differentiate rapidly growing dematiaceous molds?
- Alternaria
- Scedosporium
- Upon culture, Lomentospora prolificans mold has a gray or black surface and reverse; the annellides have swollen bases and thin necks.
- Mucormycetes
- Introduction to Mucormycetes
- Mucormycetes, continued
- If Mucormycosis (previously called zygomycosis) is clinically suspected, then how should a tissue specimen be prepared prior to culture?
- The Mucor species do not produce rhizoids.
- Dimorphic Fungi: Describe, Recognize, and Identify
- Dimorphic Fungi
- Characteristics of Dimorphic Fungi
- The thermally dimorphic fungi grow as yeast when incubated at 25° C but grow as molds when incubated at 30° or 37° C.
- Coccidioides
- Arthroconidia of Coccidioides spp. are oval-shaped and alternate with empty cells.
- Coccidioides, continued
- In addition to culture, diagnosis of coccidioidomycosis can be accomplished by which of the following?
- Paracoccidioides brasiliensis
- Paracoccidioides brasiliensis gives the appearance of a mariner's wheel in tissue sections or primary wet preparations.
- Paracoccidioides brasiliensis, continued
- Blastomyces
- Blastomyces, continued
- What characteristic budding morphology can help identify Blastomyces species?
- Diagnosis of blastomycosis can be made with an antigen test performed on urine or serum.
- Histoplasma
- Which cells are H. capsulatum yeast cells often found within?
- Histoplasmosis
- Sporothrix schenckii
- Microscopically, S. schenckii mold produces very delicate hyaline septate hyphae producing conidiophores topped by clusters of macroconidia ("rosettes...
- Talaromyces marneffei
- How do T. marneffei yeast-forms replicate?
- Current and Emerging Techniques for the Diagnosis of Mycotic Infection
- Molecular and MALDI Identification Techniques
- One important limitation to the identification of medically important fungi using the MALDI method is:
- References
Additional Information
Level of Instruction: Basic to intermediate
Intended audience: This course is intended for microbiology bench technicians, scientists, supervisors, and administrators. A basic understanding of mycology media and stains is suggested.
Author Information: Timothy Walls, M.D., M.S., is an AP/CP-boarded pathologist. He has completed fellowships in medical microbiology as well as molecular genetic pathology. Currently, he is the Director of Clinical Laboratories at Sentara Reference Laboratories. Timothy has earned his B.S. in Biochemistry, Cellular and Molecular Biology at the University of Tennessee, his M.S. in Forensic Science at Drexel University, and an M.D. from the University of Tennessee Health Science Center.
Reviewer Information:
Ryan Relich, Ph.D., D(ABMM), MLS(ASCP)SM is a medical microbiologist. Dr. Relich is an Assistant Professor of Clinical Pathology and Laboratory Medicine at IU School of Medicine, conducting applied and translational research in diagnostic test development and evaluation; novel and emerging virus ecology, epidemiology, and pathogenesis; and pandemic preparedness. Dr. Relich holds a Ph.D. in microbiology (Miami University), and BS degrees in medical technology and molecular biology/biotechnology (Clarion University of Pennsylvania).
Dr. Julie Ann West is certified by the American Society for Clinical Pathology (ASCP) as a Medical Laboratory Scientist (MLS) and as a Specialist in Microbiology (SM). In addition, Dr. West has earned a Ph.D. in Public Health - Infectious Disease Epidemiology - and is Certified in Public Health (CPH) by the National Board of Public Health Examiners. Dr. West is experienced as a Technical Specialist, Safety Officer, Educator, and Lead in the Veterans Administration Healthcare System, and has prior experience as an Administrator.
Course Description: Upon completion of the course, the reader will have accomplished several skills: recognize the geographic distribution and anatomical predilection of the primary fungi causing human disease, recognize the clinical manifestation of disease, and identify pathogenic fungi through their unique distinguishing features such as culture growth characteristics and morphology.
