MLAB 1331 – MYCOLOGY

 

CHARACTERISTICS OF FUNGI

DIVERSE GROUPS OF ORGANISMS , GENERALLY CLASSIFIED AS MOLDS OR YEASTS; SOME ARE PATHOGENS AND OTHERS ARE SAPROBES.

4 PHYLA

 

PRACTICAL CLASSIFICATION OF FUNGI

         SUPERFICIAL OR CUTANEOUS MYCOSES –FUNGAL INFECTIONS INVOLVING HAIR,
SKIN OR NAILS WITH NO DEEP INVASION OF TISSUES; ALL INFECT KERATINIZED TISSUES ; INCLUDE THE DERMATOPHYTES

         SUBCUTANEOUS MYCOSES – FUNGI THAT INFECT SUBCUTANEOUS TISSUE WITHOUT DISSEMINATING TO OTHER SITES; INCLUDE CHROMOBLASTOMYCOSIS, MYCETOMA AND PHAEOHYPHOMYCOTA

         SYSTEMIC MYCOSES – INFECTIONS INVOLVE THE LUNGS BUT MAY DISSEMINATE AND INVOLVE ORGAN SYSTEMS; INCLUDE BLASTOMYCES, COCCIDIOIDES, HISTOPLASMA AND PARACOCCIDIOIDES

         OPPORTUNISTIC MYCOSES – INFECTIONS OCCUR IN THE IMMUNOSUPPRESSED AND IMMUNOCOMPROMISED PATIENT; INCLUDE ASPERGILLUS, ZYGOMYCETES, CANDIDA AND CRYPTOCOCCUS

 

YEAST versus MOLD

HYPHAE – AERIAL OR VEGETATIVE TYPES OF HYPHAE

OTHER CHARACTERISTICS

 

DIMORPHIC FUNGI

REPRODUCTIVE STRUCTURES OF FUNGI

 

OTHER FUNGAL ROLES

         FOOD PROCESSING

1.        BEER AND WINE FERMENTATION

2.        CHEESE

3.        BREADMAKING

LABORATORY SAFETY

CLINICAL SITES AND SPECIMENS

 

 

         RESPIRATORY TRACT SPECIMENS

         CEREBROSPINAL FLUID

         BLOOD

         HAIR, SKIN AND NAIL SCRAPINGS

         URINE

         TISSUE

         BONE MARROW

         STERILE BODY FLUIDS

 

 

CULTURE MEDIA AND INCUBATION REQUIREMENTS

 

 

 

 

 

 

 

IDENTIFICATION OF FUNGI

 

DIRECT EXAMS

1.                    KOH – POTASSIUM HYDROXIDE 10-20% SOLUTION OF KOH, USED TO DETECT FUNGUS ELEMENTS IN SKIN, HAIR, NAILS AND TISSUES.

2.                    KOH WITH CALCOFLUOR WHITE       

3.                    INDIA INK

4.                    TISSUE STAINS

5.                    ACID FAST

6.                    GRAM STAIN

(TABLE 53-8 LISTS FUNGI FEATURES IN DIRECT EXAMS)

 

EXAMINATION AND IDENTIFICATION OF THE GROWN CULTURE

 



LPCB DYE - THE COMBINATION OF LACTIC ACID, PHENOL AND THE BLUE DYE KILLS, PRESERVES AND STAINS THE ORGANISMS

VIRULENCE FACTORS

 

 

 

 

 

YEAST

CANDIDA ALBICANS

SPECIMENS

GERM TUBE TEST FOR CANDIDA ALBICANS

 

CRYPTOCOCCUS NEOFORMANS

INDIA INK FOR CRYPTOCOCCUS NEOFORMANS

OTHER YEAST IDENTIFICATION SYSTEMS

         COMMERCIAL YEAST ID SYSTEMS ARE UTILIZED
THEY ARE RAPID AND RESULTS ARE AVAILABLE IN 72 HOURS
ID BASED ON A DATABASE OF NUMEROUS YEAST BIOTYPES
EXAMPLES: API-20, UNI-YEAST TEK, MICROSCAN YEAST PANEL, VITEK BIOCHEMICAL CARD, CHROMAGAR AND RAPID YEAST PLUS

         CONVENTIONAL METHODS BESIDES GERM TUBE INCLUDE CORNMEAL AGAR MORPHOLOGY, CARBOHYDRATE UTILIZATION, NIGER SEED AGAR, RAPID UREASE TEST, AND SERODIAGNOSIS


TRICHOSPORON BEIGELLII

MALASSEZIA FURFUR

ZYGOMYCETES: THE HYALINE, ASEPTATE OR SPARSELY SEPTATE MOLDS

ABSIDIA

MUCOR

RHIZOPUS

DERMATOPHYTES: HYALINE, SEPTATE, MONOMORPHIC MOLDS
 

         THEY ARE DISTRIBUTED WORLDWIDE, SOIL, ANIMALS AND HUMANS

 

LABORATORY SPECIMENS

TRICHOPHYTON

         WIDELY DISTRIBUTED AND MOST IMPORTANT AND COMMON CAUSE OF INFECTIONS OF HAIR, SKIN AND NAILS

         MOST ARE ANTHROPOPHILIC – HUMAN –LOVING

         FEW ARE ZOOPHILIC – INFECTING ANIMALS

         HAIRS INFECTED  WILL NOT FLUORESCE UNDER ULTRAVIOLET OF WOOD’S LAMP

TRICHOPHYTON MENTAGROPHYTES

         CAUSES INFLAMMATORY TINEA PEDIS, TINEA CORPORIS, TINEA UNGUIUM, TINEA BARBAE AND TINEA CAPITIS

         GROWTH RATE 7-10 DAYS

         WHITE GRANULAR AND FLUFFY COLONIES; YELLOW PERIPHERY WITH REVERSE BUFF TO REDDISH BROWN

         ROUND GRAPE-LIKE CLUSTERS OF MICROCONIDIA ON HAIR  

         MACROCONIDIA ARE THIN-WALLED, SMOOTH, MULTISEPTATE; NUMEROUS OR RARE

         FEW SPIRAL HYPHAE

         POSITIVE UREA AGAR

TRICHOPHYTON RUBRUM

TRICHOPHYTON TONSURANS

MICROSPORUM  AUDOUINII

MICROSPORUM CANIS

MICROSPORUM GYPSUM

EPIDERMOPHYTON FLOCCOSUM

OPPORTUNISTIC MYCOSES: HYALINE, SEPTATE, MONOMORPHIC MOLDS

ASPERGILLUS

ASPERGILLUS FUMIGATUS

ASPERGILLUS NIGER

ASPERGILLUS FLAVUS

FUSARIUM

GEOTRICHUM

 

 

ACREMONIUM

 

 

PENICILLIUM SPECIES

PAECILOMYCES

SCOPULARIOPSIS SPECIES

SYSTEMIC MYCOSIS: HYALINE SEPTATE DIMORPHIC MOLDS

SYSTEMIC MYCOSES

BLASTOMYCES DERMATITIDIS

COCCIDIOIDES IMMITIS

HISTOPLASMA CAPSULATUM

PARACOCCIDIODES BRASILIENSIS

SPOROTHRIX SCHENCKII

SEPTATE DEMATIACEOUS MOLDS

 

SUPERFICIAL INFECTIONS – TINEA NIGRA AND BLACK PIEDRA; THESE DISEASES OCCUR PRIMARILY IN TROPICAL AREAS OF THE WORLD

 

EXOPHIALA WERNICKII

PIEDRA HORTAE

MYCETOMA – CHRONIC GRANULOMATOUS INFECTION THAT INVOLVES LOWER EXTREMITIES BUT CAN OCCUR IN ANY PART OF BODY

 

MYCETOMA TYPE I – ACTINOMYCOTIC (BACTERIAL) MYCETOMA CAUSED BY NOCARDIA, ACTINOMADURA AND STREPTOMYCES

 

MYCETOMA TYPE II – EUMYCOTIC MYCETOMA CAUSED BY FUNGI

         PUS CONTAINS GRANULES OF COMPACT MYCELIAL MASSES

 

         GRANULES EXAMINED FOR COLOR (LIGHT OR DARK), SIZE, TEXTURE (SOFT OR HARD)

         SHOULD BE CULTURED ON FUNGAL MEDIA

         DIRECT EXAM STAINS LOOK FOR HYPHIAL ELEMENTS

 

 

PSEUDALLESCHERIA BOYDII

 

ACREMONIUM

 

EXOPHIALA JEANSELMEI

         BLACK GRAIN MYCETOMA

 

CRUVULARIA

         BLACK GRAIN MYCETOMA

         ARE TWISTED AT THE ENDS WHERE CONIDIA ARE ATTACHED

         CAUSES SINUSITIS

         DEMATIACEOUS AND SEPTATE HYPHAE

         SUBCUTANEOUS, HEART VALVES, EYE AND LUNGS

         FLUFFY OR DOWNY, OLIVE TO GRAY TO BLACK COLONY

 

MADURELLA MYCETOMATIS

 

 

CHROMOBLASTOMYCOSIS – CHRONIC FUNGAL INFECTIONS ACQUIRED VIA TRAUMATIC INOCULATION OF AN ORGANISM, PRIMARILY SKIN AND SUBCUTANEOUS TISSUE. CHARACTERIZED BY THE DEVELOPMENT OF PAPULE THAT SLOWLY FORMS ITCHY WARTY NODULES ON SKIN (FEET AND LEGS)

 

                                                                          CLADOSPORIUM

 

PHIALOPHORA

 

FONSECAEA

 

PHAEHOHYPHOMYCOSIS - INFECTIONS CAUSED BY DEMATIACEOUS FUNGI THAT FORM PIGMENTED HYPHAE AND YEASTLIKE CELLS IN TISSUE; CAN BE SUBCUTANEOUS, LOCALIZED OR SYSTEMIC

ALTERNARIA

DRECHSLERA

         RAPID GROWER, VELVETY - GRAYISH-BROWN TO BLACK

         MICROSCOPICALLY, THE HYPHAE IS SEPTATE AND DEMATIACEOUS

         CONIDIA ARE GENICULATE – SERIES OF BENT KNEE STRUCTURES

         DEMATIACEOUS, MULTICELLED CONIDIA

 

CURVULARIA

 

EXOPHIALA

 

 

EXSEROHILUM

 

 

 

 

 

PNEUMOCYSTIS CARINII – ATYPICAL FUNGI