Assist Prof Dr. Syed Yousaf Kazmi MAJOR FUNGI Assist Prof Dr. Syed Yousaf Kazmi

OBJECTIVES Classify Fungi Clinical significance of fungal infections List common diseases caused by fungi Importance of opportunistic fungal infections in human

INTRODUCTION TO FUNGI 80,000 species of fungi- less than 400 are medically important Beneficial to humankind Breaking down and recycling organic matter Production of food and spirits, including cheese, bread, and beer Antibiotics (eg, penicillin) and immunosuppressive drugs e.g. Cyclosporine

INTRODUCTION TO FUNGI Eukaryotic Organisms Yeast Form (Unicellular), Mold Form (Multicellular) Obligate or facultative aerobes Natural habitats being water, soil, and organic debris Human are gen resistant to fungal infections Some form of immune deficiency in patients with fungal infections Normal flora e.g. Candida albicans

Classification of the fungi True yeast Cryptococcus neoformans Yeast like fungi Candida albicans Dimorphic fungi Histoplasma capsulatum, Blastomyces dermatidis Moulds Aspergillus fumigatus

CLASSIFICATION OF FUNGI Category Mycosis Causative Fungal Agents SUPERFICIAL Pityriasis versicolor Malassezia species CUTANEOUS Dermatophytosis Microsporum species, Trichophyton species, and Epidermophyton floccosum Candidiasis of skin, mucosa, or nails Candida albicans and other Candida species SUBCUTANEOUS Sporotrichosis Sporothrix schenckii Mycetoma Pseudallescheria boydii, Madurella mycetomatis, and others ENDEMIC (PRIMARY, SYSTEMIC) Coccidioidomycosis Coccidioides posadasii and Coccidioides immitis Histoplasmosis Histoplasma capsulatum OPPORTUNISTIC Systemic candidiasis Cryptococcosis Cryptococcus neoformans and Cryptococcus gattii Aspergillosis Aspergillus fumigatus etc Mucormycosis (zygomycosis) Species of Rhizopus, Absidia, Cunninghamella,

FUNGAL DISEASES IN HUMANS Allergic reaction Result from inhaling fungal spores React to fungal toxin Many have hallucinogenic properties Certain species produces toxins implicated in cancer. e.g. Aflatoxin Mycoses Fungi grows on or in the body Can be superficial, intermediate, systemic Economic impact Destroy human food supply causing starvation

FUNGAL ALLERGIES & MYCOTOXICOSES Fungal spores -common sources of Atopic allergies Asthma, Farmer’s lung, Fungal toxins lead to mycotoxicoses Ergot poisoning -ingestion of moldy grain Fungal Aflatoxin related to human cancer

FUNGAL DISEASES-MYCOSIS Mycoses are classified into Superficial mycoses: Infections of hair shafts and superficial epidermal cells. Prevalent in tropical climates Cutaneous mycoses: keratinized epidermis (skin, hair, nails) Trichophyton, Microsporum, Epidermophyton Examples: Ringworm (Tinea capitis and T. corporis) Athlete’s foot (Tinea pedis) Jock itch (Tinea cruris)

FUNGAL DISEASES-MYCOSIS Subcutaneous mycoses: Invade traumatized beneath skin Destructive local lesions Lymphocutaneous sporotrichosis Chromoblastomycosis Mycetomal -Systemic mycoses: Fungal infections deep within the body Usually caused by fungi that live in the soil and are inhaled. Examples: Histoplasmosis (Histoplasma capsulatum): Coccidiomycosis (Coccidioides immites):

FUNGAL DISEASES Opportunistic mycoses: Caused by organisms that are generally harmless unless individual has weakened defenses: - AIDS and cancer patients - Individuals treated with broad spectrum antibiotics -Very old or very young individuals (newborns). e.g. Inhalation of Aspergillus spores. Yeast Infections by Candida albicans.

CUTANEOUS FUNGAL INFECTIONS: Thrush 1.Candidiasis ,most common, the normal flora of the GIT. Oral cavity and esophagus are the two most common clinical manifestations of candidiasis in HIV-infected patients. 2. Dermatophytes Grows best on warm and moist surfaces Other species in the genus Candida such as C. glabrata C. krusei C. trophicalis etc., less common 1+2 very localized infection of the skin or mucosal membranes, including the oral cavity (thrush)pharynx or esophagus,GIT, urinary bladder, genitalia (vagina, penis) . Skin infection and occasionally nail infection may also occur. 3.Pityriasis versicolor

Cutaneous Mycosis Candida albicans infection of the nails.

MYCETOMA When Soil Microbes Are Accidentally Implanted Into The Skin Progressive, Tumor-like Disease Of The Hand Or Foot Due To Chronic Fungal Infection; May Lead To Loss Of Body Part Caused By Pseudallescheria or Madurella

Tinea Capitis Gray Patch

Tinea corporis – body ringworm

Tinea Unguium – Nail Infection

Tinea Pedis – Athlete’s Foot Infection

Superficial mycoses Tinea versicolor causes mild scaling, mottling of skin White piedra is whitish or colored masses on the long hairs of the body Black piedra causes dark, hard concretions on scalp hairs White & black piedra Transmission is often mediated by shared hair brushes or combs Several members of a family are usually infected at the same time Infected areas must often be shaved to remove the fungi

Cryptococcus neoformans A widespread encapsulated yeast that inhabits soils around pigeon roosts Common infection of AIDS, cancer or diabetes patients Infection of lungs leads to cough, fever, & lung nodules Dissemination to meninges & brain can cause severe neurological disturbance & death

Pneumocystis jerovecii A small, unicellular fungus that causes pneumonia (PCP), the most prominent opportunistic infection in AIDS patients This pneumonia forms secretions in the lungs that block breathing & can be rapidly fatal if not controlled with medication

MUCORMYCOSIS Genera most often involved are Rhizopus, Absidia, & Mucor Destructive invade the membranes of the nose, eyes, heart, & brain Strong association with diabetes mellitus

LIST OF IMPORTANT FUNGAL INFECTIONS Candidiasis Cryptococcosis Pneumocystis jerovecii Aspergillosis Tinea + Maduromycosis Blastomycosis Histoplasmosis Coccidioidomycosis Paracoccidioidomycosis Mucormycosis