Fungi

Question 1

Three common fungal causes of acute pneumonia?

Answer 1

• Histoplasma capsulatum
• Coccidioides immitis
• Mucormycosis (rhizopus)

Question 2

Five common fungal causes of chronic pneumonia syndrome?

Answer 2

• aspergillus
• blasto derm
• coccidioides
• histo
• cryptococcus neoformans

Question 3

Which 3 fungi are associated with infections in patients with granulocyte dysfunction (neutropenia)?

Answer 3

• aspergillosis
• zygomycosis
• candidiasis

Question 4

Which 5 fungi are associated with infections in patients with depressed CMI?

Answer 4

• candida (mucosal)
• coccidioidomycosis
• cryptococcus
• histoplasmosis
• pneumocytosis

Question 5

Most prevalent and most virulent aspergillus species?

Answer 5

• fumigatus

- flavus

Question 6

Mycology of aspergillus?

Answer 6

• MOLD

- narrow, branching, septate hyphae

Question 7

Most widely used test for aspergillus detection?

Answer 7

• galactomannan antigen test (immunofluoresence)

Question 8

Three allergic classifications of aspergillosis?

Answer 8

• extrinsic allergic alveolitis
• extrinsic asthma and allergic bronchopulmonary aspergillosis (ABPA)
• allergic sinusitis

Question 9

What kind of patient does extrinsic allergic alveolitis with aspergillus occur in?

Answer 9

• farmer or malt work

- non-atopic workers to antigen in moldy hay/grain

Question 10

What kind of patients does ABPA occur in?

Answer 10

• children, adolescents and young adults with asthma

- allergic response to hyphae without direct tissue invasion

Question 11

What kind of patient does allergic sinusitis with aspergillus occur in?

Answer 11

• immunocompetent atopic patient with history of repeated bouts of sinus congestion

Question 12

What kind of patient does saprophytic aspergillosis occur in?

Answer 12

• patients with cavities due to TB, sarcoid, bronchiectasis, pneumoconiosis, CF
• fungal balls –> local hemorrhage

Question 13

Three major predisposing factors to invasive aspergillosis?

Answer 13

• granulocytopenia
• high dose corticosteroids
• HIV

Question 14

What is the airborne form of mucormycosis?

Answer 14

sporangiospores (contains lots of individual spores)

Question 15

Unique, common predisposing factor to mucormycosis?

Answer 15

• DM

Question 16

Structure of mucomycosis? Diagnosis?

Answer 16

• broad, irregularly wide, non-septate hyphae

- NO serology available

Question 17

Presentation of pulmonary mucormycosis?

Answer 17

• persistent fever and pulmonary infiltrates refractory to AB Tx
• consolidation involving one or multiple lobes
• endobronchial masses, erosion of bronchi, bronchopleural, and broncocutaneous fistulae and granulomatous mediastinitis

Question 18

Two AIDS-defining pulmonary illnesses?

Answer 18

• Cryptococcus neoformans

- Pneumocystis jirovecii

Question 19

What is the morphology of cryptococcus?

Answer 19

• encapsulated yeast (polysaccharide capsule with India Ink)

Question 20

How does cryptococcus manifest in COPD patients? IC?

Answer 20

• pneumonia with nodular lesions/cavitary disease/pleural effusions
• disseminated disease – meningoencephalitis, cutaneous lesions

Question 21

Primary predisposing factor to PCP?

Answer 21

• CD4 T cell defect caused by HIV infection

Question 22

How does PCP usually present? (pneumocystis jirovecii)

Answer 22

• pneumonia
• history of dry cough, fever, dyspnea, difficulty with deep inspiration
• bilateral diffuse infiltrates with ground-glass appearance
• extra-pulmonary infections rare

Question 23

Histopathology of PCP?

Answer 23

characteristic eosinophilic honeycombed material in alveolar space with H&E

Question 24

Geographic distribution and morphology of Histoplasma capsulatum?

Answer 24

• Mississippi-Ohio River valleys
• dimorphic
• mold in environment = septate hyphae, large tuberculated conidia and small smooth conidia
• yeast in tissue = small, single bud with narrow septum

Question 25

Three pulmonary disease manifestations of histo?

Answer 25

- acute primary pulmonary: immunocompetent with heavy inoculum; influenza-like illness, self-limiting (diffuse alveolar infiltration or military pattern that resolves with calcifications) - chronic cavitary pulmonary: COPD; indolent but progressive respiratory infection (low grade fever, productive cough, dyspnea, night sweats) - asymptomatic infection: fungemia and dissemination that could reactivate later

Question 26

How does histo present in the immunocompromised?

Answer 26

dissemination

Question 27

Diagnosis of histo?

Answer 27

serology, agglutination, complement fixation, immunofluorescence

Question 28

Morphology of blastomyces dermatiditis? Specific environmental association?

Answer 28

- dimorphic - mold in environment = septate hyphae, conidia on slender conidiophores - yeast in tissue = thick walled, budding, WIDE septum - bodies of water -- Mississippi-Missouri River valleys

Question 29

Four pulmonary manifestations of blastomycosis?

Answer 29

- 70% asymptomatic - acute or subacute with influenza-like symptoms in immunocompetent patients - chronic that may progress to dissemination particularly in IC patients

Question 30

What fungal disease is fulminant with ARDS?

Answer 30

Blastomycosis

Question 31

What cross-reaction can complicate blastomycosis serology?

Answer 31

- H. capsulatum

Question 32

What other animal is highly susceptible to blastomycosis?

Answer 32

- canines | - not contagious to humans from dogs

Question 33

Geographical distribution and morphology of coccidioidomycosis?

Answer 33

- desert southwest and deserts of Central and South America - dimorphic - mold in soil = septate hyphae with arthroconidia - spherules containing endospores in tissues

Question 34

What fungal disease is associated with erythema nodosum? Implications?

Answer 34

- Coccidioidomycosis | - associated with good prognosis

Question 35

How does cocci present as a pulmonary disease?

Answer 35

- initial infection = self-limiting - complications occur in IC -- nodules, cavities, progressive pneumonia, pyopneumothorax, bronchopleural fistula - extra pulmonary disease: skin, soft tissue, osteomyelitis, arthritis, meningitis

Question 36

Which fungus exists as spherules instead of yeast in tissue?

Answer 36

Cocci