Fungi and Their Clinical Relevance

These flashcards cover the critical vocabulary, definitions, and concepts related to fungi, their characteristics, types of infections they cause, and their clinical relevance.

Yeast

Single-celled fungi that grow as smooth, creamy colonies and reproduce mainly by budding.

Molds

Multicellular fungi that grow with fuzzy appearances due to aerial hyphae and reproduce by producing spores.

Fungi

Eukaryotic organisms that cannot produce their own food, absorb nutrients from the environment, and have cell walls made of chitin.

Chitin

A tough, flexible polysaccharide that makes up the cell walls of fungi, providing resistance to environmental stress.

Opportunistic Fungal Infections

Infections caused by fungi that occur when the immune system is compromised, often seen in patients with HIV/AIDS, organ transplants, or undergoing chemotherapy.

Dimorphism

The ability of certain fungi to exist in two different forms (mold and yeast) depending on environmental conditions.

Mycoses

Fungal infections that can be superficial, cutaneous, subcutaneous, systemic, or opportunistic, varying from mild to severe.

Eukaryotic

Organisms, like fungi, whose cells contain a nucleus and membrane-bound organelles.

Polymorphism

The ability of fungi to exhibit multiple forms (e.g., yeast and mold) in the same culture.

Fragmentation

An asexual reproduction method where fungal mycelium breaks into pieces, each capable of growing into a new colony.

Budding

A method of asexual reproduction in yeasts where a small bud forms on the parent cell and eventually separates.

Fission

A method of asexual reproduction in yeasts where the cell elongates, the nucleus divides, and the cell splits into identical daughter cells.

Hyaline Hyphae

Nonpigmented or lightly pigmented fungal hyphae appearing clear or white under microscopy.

Phaeoid Hyphae

Darkly pigmented hyphae due to the presence of melanin, providing increased virulence.

Clinical Relevance of Fungi

Understanding fungi is crucial for identifying infections, their risk factors, and appropriate treatment methods.

Candida albicans

A common yeast that can cause mucosal infections and is significant in immunocompromised patients.

Rhizopus

A mold commonly found on bread that is important in the discussion of fungal infections.

Penicillium

A genus of molds that includes species known for antibiotic production but can also be pathogenic.

Cryptococcus

A pathogenic yeast, notably Cryptococcus neoformans, associated with serious infections, particularly in immunocompromised hosts.

HIV/AIDS and Fungi

Patients with HIV/AIDS experience a loss of CD4+ T cells, increasing susceptibility to opportunistic fungal infections.

Organ Transplantation and Fungi

Lifelong immunosuppressive therapy post-transplant increases the risk of fungal infections.

Broad-spectrum antibiotics and fungi

Use of these antibiotics can suppress normal flora and promote opportunistic fungal growth.

Iron Overload and Fungi

Patients with iron overload or receiving deferoxamine therapy are at higher risk for fungal infections due to increased availability of iron.