Fungi Flashcards
“Histoplasma capsulatum
(historian’s cave)”
Features:“*Smaller than RBC
* Dimorphic
* Yeast lives in macrophages
* Granulomatous inflammation
Clinically similar to TB”
Location:” Midwestern/Central US
* MI & OH Rivers”
Symptoms:“Acute: Asymp pulm infection that can disseminate
* Vague symptoms: fever, chills, sweats, fatigue
* Erythema nodosum (painful nodules on legs/shins)
Chronic: liver, spleen, bone marrow
* Lung granuloma becomes calcified
*Cavitary lesions in upper lobes, calcified nodules, fibrosis; resembles TB (SOB, cough)
Hepatosplenomegaly w calc”
Diagnosis:” KOH Stain: Macrophages containing several oval bodies
* Urine rapid antigen test
*Serum rapid antigen test
*Culture of biopsy (takes VERY long)
Serology (ab titers, IgM indicates recent infection)”
Treatment:” Systemic: Amphotericin B
* Local: Conazoles
- HIV PPX (TMP-SMX) in those living in endemic areas”
Syetemic fungi
“Blastomycosis
(blast of the cannons)”
Features:”* Dimorphic
Broad based budding (yeast form)
Thick, well defined walls
* Same size as RBC
* Necrotizing granulomatous inflammation w suppuration”
Location:” East/Southern US
* Great Lakes & OH River Valley”
Symptoms:“Main symptoms: weight loss, fever, cough, bloody sputum, chest pain
*ONLY self-limited pulmonary disease
* Disseminates to skin (cutaneous ulcers, abscess, tissue destruction) & bone (osteomyelitis)
CXR patchy alveolar infiltrate, hazy, lesions & cavities present”
Diagnosis:” Urine antigen test
*KOH stain
*Culture (takes VERY long)
Serology (ab titers, IgM indicates recent infection)”
Treatment:” Systemic: Amphotericin B
* Local: Itraconazoles”
Syetemic fungi
“Coccidioidomycosis
(presidio san joaquin)”
Features:“*Dimorphic
*Spherules filled w endospores in lungs
Mold form are barrel shaped or filamentous arthroconidia
* Larger than RBC”
Location:“Southwest US
* San Joaquin Valley, CA
* Dust storms & earthquakes increase spread”
Symptoms:“Acute: Mostly asymptomatic; wide range of symptoms
* Chest pain, fever, cough, fatigue
* Erythema nodosum (nodules)
* Self-limited pneumonia w fever, cough, arthralgia that lasts a couple weeks
* CXR may show nothing OR cavities & nodules
Chronic:
* Targets skin & lungs
* Necrotizing granuloma (sometimes caseous)
*Disseminates to bone & meninges (meningitis)
HIV: focal or diffuse pneumonia, skin lesions, meningitis, liver/LN involvement”
Diagnosis:“*KOH stain
*Culture (takes VERY long)
Serology (ab titers, IgM indicates recent infection)”
Treatment:” Systemic: Amphotericin B
* Local: conazoles
- HIV PPX (TMP-SMX) in those living in endemic areas”
Syetemic fungi
“Paracoccidioidomycosis
(piratase del sur)”
Features:”* Dimorphic
* Yeast form appears as ship’s wheel in lungs (mult peripheral buds)
MUCH larger than RBC
* Mixed granulomatous & suppurative inflammation”
Location: South America (Brazil)
Symptoms:”* Often asymptomatic lung infection thaty may disseminate
Mucocutaneous lesions in mouth & upper resp tract
* Cervical lymphadenopathy”
Diagnosis:“KOH stain
*Culture (takes VERY long)
Serology (ab titers)”
Treatment:” Systemic: Amphotericin B
* Local: conazoles”
Syetemic fungi
“Dermatophytes
(tinea tin man)”
Features:“*Cutaneous
*Secretes keratinase
Transmitted person to person”
Location:“Cutaneous
*Secretes keratinase
Transmitted person to person”
Symptoms:“KOH stain: hyphae with skin scrapings
Woods lamp: only for microsporium”
Diagnosis:“Topical azoles (tinea)
* Oral terbinafine (onchomycosis)
*Oral griseofulvin (serious infections, lots of GI effects)”
Treatment:
Syetemic fungi
“Sporothrix schenckii
(shanked by a rose)”
Features:“Cigar shaped yeast w spiculated eosinophilic material (asteroid body); Splendore-Heopplie phenomenon
Branching hyphae mold form resembling rose thorns (25’)
* Dimorphic
* Granuloma formation with central suppuration”
Location:” Peru is epicenter
* All across US”
Symptoms:“Rose gardener’s disease
* Skin/subcutaneous infection w primary ulcer at site of entry that spreads in ascending path along draining lymphatics (satellite lesions)”
Diagnosis:“Culture: gold standard
* Biopsy: granulomas with histiocytes, multinucleated giant cells, cigar shaped budding yeast”
Treatment:“Itraconazole (lymphocutaneous sporothichosis)
*Saturated soln of potassium iodide (OLD)
* Amphotericin”
Cutaneous Mycoses
Features:
Location:
Symptoms:
Diagnosis:
Treatment:
Cutaneous Mycoses
“Candida albicans
(candid canadians)”
Features:“*Vaginal infections do not occur when pH > 4
* Catalase +
*Yeast w/ pseudohyphae at cold temp
*Mold w/ germ tubes & true hyphae at warm temp
Commonly contaminates sputum cultures”
Location:“Superficial infections in moist areas
*Candidal vulvovaginitis: pruritus, thick white discharge, edema, excoriations
* Candidal esophagitis: AIDS-defining; odynophagia, retrosternal pain
*Oral candidiasis: can be scraped off (vs leukoplakia cannot); painless, white creamy plaques
Candidial endocarditis: common in IVDU due to growth in drugs”
Symptoms:“Oral: Direct visualization or KOH stain of skin scrapings
Esophagitis: Endoscopy to visualize plaques, can biopsy & culture”
Diagnosis:“Azoles (minor infection)
*Nystatin (2nd line oral/esophageal)
* Fluconazole (vulvovaginitis, oral/esophagus)
*Amphotericin (disseminated or resistant)
* Caspofungin (disseminated + resistant to amphotericin)
*No PPX for HIV pts”
Treatment:
Opportunistic Fungal Infections
“Aspergillus fumigatus
(asparagus farm)”
Features:”* Mold
* Acute angle branching (< 45)
Septated hyphae
Conidiophores w fruiting bodies
* Catalase +”
Location:
Symptoms:“Aspergilloma: gravity-dependent fungal balls in pre-existing lung cavity (past TB or Klebsiella infection)
Allergic Bronchopulmonary Aspergillosis (ABPA): Type I HS (IgE release) non-invasive; wheezing, fever, migratory pulm infilitrate
* Angioinvasive Aspergillosis: invades blood vessels mimicing PE, infarction, fever, cough, hemoptysis, kidney failure, endocarditis
- ring enhancing brain lesions
- necrosis on paranasal sinuses”
Diagnosis: Brain CT: ring enhancing lesions
Treatment:“Voriconazole (less severe)
* Surgical debrasion (Aspergilloma)
*Amphotericin B (angioinvasive aspergillosis)
*Steroids (reduce IgE response w ABPA)”
Opportunistic Fungal Infections
“Cryptococcus neoformans
(crypt for cryptococcus)”
Features:“*Urease +
* Capsule (mucicarmine stain)
* Yeast w wide capsular halos on india ink stain
Narrow based, unequal budding”
Location:
Symptoms:“Early symptoms: cough, chest pain, weight loss, fever, dizziness
* Pneumonia (cough, dyspnea, fever)
* Pulmonary infection that resolves spont or spreads through blood to CNS
*Most common cause of fungal meningoencephalitis (lethal, permanent deficits); soap bubble lesions
* Skin infections: papule with umbilicated center usually due to disseminated disease (skin biopsy for dx)”
Diagnosis:“LP: elevated ICP
* CT scan prior (to ruleout any lesions that could precipitate herniation with LP)
*Cryptococcal antigen (specific)
*Elevated protein
*India Ink: visualize capsules as halos
* Culture of CSF
Other tests:
*Latex Agglutination Test: capsular antigen (more sensitive)
* Bronchopulmonary washing
* mucicarmine (red) or methanamine silver stains
* India Ink Stain: yeast w wide capsular halos
Brain CT: soap bubble lesions in gray matter”
Treatment:“Induction: Amphotericin + Flucytosine
*MD fluconazole
*Manage high ICP with repeat LPs
*No PPX for HIV pts”
Opportunistic Fungal Infections
“Mucormycosis/Zygomyces
(mu car auto shop)”
Features:”* Mold
* Right angle (90) branching
* Wide, non-septated hyphae (hollow tube)
* Mucor, Rhizopus (bread mold), Absidia, etc.
* Angioinvasive –> necrotizing inflammation”
Location:“Rhinocerebral/frontal lobe abscesses: penetrates cribiform plate & causes necrosis of nasal sinuses, orbit, brain (black eschars)
* Pulmonary form: angioinvasive (proliferate in blood vessel walls where there is glucose/ketone bodies)”
Symptoms:
Diagnosis:
Treatment:” Surgical removal of necrotic tissue
* Amphotericin B”
Opportunistic Fungal Infections
“Pneumocystis pneumonia
(PCP ping pong)”
Features:“Former protozoa
Targetoid/cup-shaped w silver stain
* Disc shaped yeast or cysts containing dark oval bodies”
Location:
Symptoms:“Diffuse interstitial pneumonia: intense inflammatory rxn in alveoli of lungs that impairs O2 exchange
*Non-productive cough, accelerated dyspnea (- O2 on RA), fever, no consolidations (bilateral infilitrates possible) & lung sounds may be normal (symptoms worsen over weeks)
* Frothy honeycomb/eosinophilic exudate in alveolar spaces
* AIDS-defining illness: Most common OI in AIDS pts”
Diagnosis:” Bronchoalveolar lavage (BAL): bronchoscopy w lung samples through fluid rinses
*Methamine silver stain: disc/ovoid shaped, stains for walls of cyst
Giemsa stain: identifies cysts & trophozoites
* CXR: ground glass appearance, diffuse, bilateral reticular or interstitial infilitrate
* LDH Blood Test: NOT specific, usually elevated”
Treatment:“TMP-SMX (ppx & treatment)
* Atovaquone or Pentamidine (w sulfa allergies)
* Steroids (reduce inflammation if significant)
- HIV PPX: TMP-SMX (CD4 = 50-100)”
Opportunistic Fungal Infections
Mycetoma
Features:
Location:
Symptoms:”* Chronic infection of skin, subcutaneous tissue & sometimes bone
*Usually on foot (watering can foot)”
Diagnosis:
Treatment:
Opportunistic Fungal Infections
