Fungal infections

Question 1

Fungal infections: Classification

Answer 1

• Superficial
• Subcutaneous
• Deep

Question 2

Fungal infections: Superficial

Answer 2

• Can occur in anyone + are common.
• Immunocompromised = more at risk
• In this patient group they can have a more severe presentation (e.g. patients with HIV, diabetes)

Examples:

• Oral + vaginal thrush (Candida sp.)
• Tinea e.g. athelete’s foot (Tinea pedis), ring worm (Tinea capitis)
• Fungal nail infection (onychomyocosis)
• Pityriasis versicolor

Question 3

Fungal infections: Subcutanous

Answer 3

• Not common in the UK.
• Occur mainly in tropical countries.
• Affect the dermis, subcutenaous tissue and adjacent bones.
• There is often a degree of immunocompromise.

Question 4

Fungal infections: Deep

Answer 4

Occur in patients who are immunocompromised, examples include:

• Invasive Candida sp. - e.g. candidaemia in ICU patients with central lines that have bypassed the barrier made by the skin.
• Invasive Aspergillus fumigatus - patients who have had transplants or chemotherapy.
• Pneumocystis jirovecii pneumonia (PCP) - patients who have HIV or low lymphocytes.
• Cryptococcal meningitis - patients who have HIV or other severe immunosuppression. Caused by Cryptococcus neoformans.

Question 5

Fungi: Overview

Answer 5

Superficial/cutaneous mycoses:

• Dermatophytosis
• Superficial candidiasis
• Malassezia

Systemic/invasive:

• Invasive candidiasis
• Cryptococcus
• Histoplasmosis
• Blastomycosis