Fungal Pathogens and Mycoses Overview

Fungal Pathogens

• Mycoses are difficult to diagnose due to signs being missed and fungi resisting antifungal agents.
• Fungi are pathogenic in three ways: infections (true pathogens or opportunists), toxicoses (poisonous mushrooms), or allergies (inhaled spores).
• Amphotericin B is often the first-line drug for fungal infections.

Pathogenesis of Systemic Mycoses

• Histoplasma: Usually asymptomatic, inhalation of spores is common.
  • Histoplasma capsulatum is engulfed by macrophages, then spreads via blood and lymph.
• Blastomyces: Blastomyces dermatitidis is the causative agent, found in moist soil and decaying leaves.
  • Initial symptoms are nonspecific (muscle aches, fever, chills).
• Coccidioides: Coccidioides immitis is the causative agent, found in desert soil and other locations.
  • Primarily pulmonary, with potential for dissemination in immunocompromised hosts.

Pneumocystis Pneumonia

• Pneumocystis jiroveci is an opportunistic fungal infection, commonly affecting AIDS patients.
• Most people are exposed to P. jiroveci by age five.

Candidiasis

• A common microbiota found in skin and mucous membranes, transmissible between individuals.
• Oral thrush (candiasis) can also occur.
• Vaginal candidiasis is a form of yeast infection.
• Affects immunocompromised individuals more severely.

Dermatophytosis (Ringworm)

• Infections of skin/nails/hair.
• Spread from person-to-person.

Explore the complex world of fungal pathogens and their impact on human health. This quiz encompasses mycoses, their pathogenesis, and the specific pathogens like Histoplasma, Blastomyces, and Coccidioides. Test your knowledge on diagnosis, treatment, and the unique characteristics of these microorganisms.