8.3-ASPERGILLOSIS+MUCORMYCOSIS

Question 1

What is the causative agent of Aspergillosis?

Answer 1

Aspergillus spp

Question 2

What are the five most common Aspergillus species causing disease?

Answer 2

A. fumigatus (most common)
A. flavus
A. niger
A. terreus
A. lentulus

Question 3

What is the mode of transmission (MOT) for Aspergillus?

Answer 3

Inhalation of conidia (spores)

Question 4

What kind of fungi are Aspergillus species?

Answer 4

Ubiquitous saprobes (colonizing soil, plants, grains)

Question 5

What type of immune reaction can Aspergillus cause in atopic individuals?

Answer 5

Severe allergic reactions to conidial antigens

Question 6

What happens when immunocompromised patients inhale Aspergillus conidia?

Answer 6

Conidia germinate, forming hyphae that invade the lungs and other tissues

Question 7

What is the causative agent of Aspergillosis?

Answer 7

Aspergillus spp.

Question 8

What are the five most common Aspergillus species causing disease?

Answer 8

A. fumigatus (most common); A. flavus; A. niger; A. terreus; A. lentulus

Question 9

What is the mode of transmission (MOT) for Aspergillus?

Answer 9

Inhalation of conidia (spores)

Question 10

What kind of fungi are Aspergillus species?

Answer 10

Ubiquitous saprobes (colonizing soil, plants, grains)

Question 11

What type of immune reaction can Aspergillus cause in atopic individuals?

Answer 11

Severe allergic reactions to conidial antigens

Question 12

What happens when immunocompromised patients inhale Aspergillus conidia?

Answer 12

Conidia germinate, forming hyphae that invade the lungs and other tissues

Question 13

Which Aspergillus species is the most common cause of aspergillosis?

Answer 13

A. fumigatus

Question 14

What is a key morphological feature of A. fumigatus?

Answer 14

Sporulation occurs only from the upper half or two-thirds of the vesicle

Question 15

What does an A. niger colony look like?

Answer 15

White with black pepper-like growth → Forms a radiate head

Question 16

What does an A. flavus colony look like?

Answer 16

Yellow to yellow-green → Phialides cover the entire vesicle, pointing in all directions

Question 17

What does an A. terreus colony look like?

Answer 17

Brown colonies → Phialides cover the entire vesicle

Question 18

What is the first line of defense against Aspergillus conidia?

Answer 18

Alveolar macrophages engulf and destroy conidia

Question 19

What happens if conidia survive in the lungs?

Answer 19

Conidia swell and germinate; Hyphae invade lung tissue and blood vessels; May cause aspergilloma (fungus ball) in preexisting lung cavities

Question 20

What are the hallmark features of allergic bronchopulmonary aspergillosis (ABPA)?

Answer 20

Asthmatic reaction; Recurrent chest infiltrates; Eosinophilia; Type I (immediate) & Type III (Arthus) hypersensitivity

Question 21

What symptoms are common in ABPA?

Answer 21

Difficulty breathing; Sputum with Aspergillus; Serum precipitins; Lung scarring

Question 22

What can exposure to massive doses of conidia cause in normal hosts?

Answer 22

Extrinsic allergic alveolitis

Question 23

Aside from the lungs, what other infections can Aspergillus cause?

Answer 23

Keratitis (eye); Nail infections; Endocarditis (heart); CNS infections

Question 24

What is aspergilloma, and how does it form?

Answer 24

Fungus ball in preexisting lung cavities; Forms when inhaled conidia germinate & produce hyphae

Question 25

What lung condition increases the risk for aspergilloma?

Answer 25

Cavitary diseases (e.g., tuberculosis, lung abscesses)

Question 26

What are the symptoms of aspergilloma?

Answer 26

Cough; Dyspnea; Weight loss; Fatigue; Hemoptysis (coughing up blood)

Question 27

How is aspergilloma usually treated?

Answer 27

Lobectomy (surgical removal of affected lung area)

Question 28

Who is at highest risk for developing aspergilloma?

Answer 28

Immunocompromised patients (e.g., diabetics, corticosteroid users, AIDS patients)

Question 29

What noninvasive Aspergillus infections can occur?

Answer 29

Localized colonization in: Nasal sinuses; Ear canal; Cornea; Nails

Question 30

What is invasive aspergillosis?

Answer 30

Acute pneumonia with or without dissemination

Question 31

What organs can invasive Aspergillus spread to?

Answer 31

Gastrointestinal tract; Kidney; Liver; Brain; Other organs

Question 32

What patients are at highest risk for invasive aspergillosis?

Answer 32

Lymphocytic or myelogenous leukemia; Lymphoma patients; Stem cell transplant recipients; Patients on corticosteroids; AIDS patients (CD4 <50 cells/uL)

Question 33

What is the main risk factor for invasive aspergillosis in stem cell transplant patients?

Answer 33

Allogeneic transplants (higher risk than autologous transplants)

Question 34

What are the symptoms of invasive aspergillosis?

Answer 34

Fever; Cough; Dyspnea; Hemoptysis; Thrombosis, infarction, necrosis

Question 35

What is the gold standard for diagnosing Aspergillus infections?

Answer 35

Culture & histopathology

Question 36

What are the specimen types used for diagnosis?

Answer 36

Sputum; Bronchoalveolar lavage (BAL); Tissue biopsy; Blood (for disseminated infection)

Question 37

What is the key histopathological feature of Aspergillus?

Answer 37

Septate hyphae with acute-angle branching (45° angle)

Question 38

What serologic test is used to detect Aspergillus antigen?

Answer 38

Galactomannan antigen test

Question 39

What is the first-line treatment for invasive aspergillosis?

Answer 39

Voriconazole

Question 40

What are alternative antifungal treatments for Aspergillus?

Answer 40

Amphotericin B; Echinocandins (Caspofungin, Micafungin, Anidulafungin)

Question 41

Is aspergilloma (fungus ball) treated with antifungal drugs?

Answer 41

No, it requires surgical removal (lobectomy)

Question 42

Where is Aspergillus found in the environment?

Answer 42

Soil, decaying plants, grains, air

Question 43

What group of people should be extra cautious about Aspergillus exposure?

Answer 43

Immunocompromised individuals (e.g., transplant recipients, HIV/AIDS patients, plant enthusiasts in high-risk groups)

Question 44

What are the common specimen types used for Aspergillus diagnosis?

Answer 44

Sputum, respiratory tract specimens, lung biopsy tissue, blood samples

Question 45

What is the key microscopic feature of Aspergillus hyphae?

Answer 45

Hyaline, septate, uniform width (~4 µm), and dichotomous branching

Question 46

How quickly do Aspergillus species grow on culture media?

Answer 46

Within a few days at room temperature

Question 47

How are Aspergillus species identified?

Answer 47

By the morphology of their conidial structures

Question 48

What serologic test is positive in 80% of patients with aspergilloma or allergic aspergillosis?

Answer 48

ID test for precipitins to A. fumigatus

Question 49

What serologic marker is used for diagnosing invasive aspergillosis?

Answer 49

Circulating cell wall galactomannan

Question 50

What additional fungal marker helps diagnose invasive aspergillosis and candidiasis?

Answer 50

β-glucan detection

Question 51

What are the treatment options for aspergilloma?

Answer 51

Itraconazole or amphotericin B + surgery

Question 52

What is the first-line treatment for invasive aspergillosis?

Answer 52

Amphotericin B (native/lipid formulation) or voriconazole

Question 53

What adjunct therapy is often given for invasive aspergillosis?

Answer 53

Cytokine immunotherapy

Question 54

What antifungal is used for Amphotericin B-resistant Aspergillus species?

Answer 54

Posaconazole (for A. terreus, A. flavus, A. lentulus)

Question 55

What is the treatment for less severe chronic necrotizing pulmonary aspergillosis?

Answer 55

Voriconazole or itraconazole

Question 56

How are allergic forms of aspergillosis treated?

Answer 56

Corticosteroids or disodium cromoglycate

Question 57

What is the main preventive strategy for individuals at high risk for invasive aspergillosis?

Answer 57

Avoid exposure to Aspergillus conidia

Question 58

What prophylactic antifungal therapy is given to high-risk patients?

Answer 58

Low-dose amphotericin B or itraconazole

Question 59

What is another name for mucormycosis?

Answer 59

Zygomycosis

Question 60

What fungal order causes mucormycosis?

Answer 60

Mucorales

Question 61

What phylum and subphylum do Mucorales belong to?

Answer 61

Phylum Glomerulomycota, Subphylum Mucoromycotina

Question 62

What type of fungi are Mucorales?

Answer 62

Ubiquitous, thermotolerant saprobes

Question 63

What are the leading genera of fungi causing mucormycosis?

Answer 63

Rhizopus, Rhizomucor, Lichtheimia, Cunninghamella, Mucor

Question 64

What are the major risk factors for mucormycosis?

Answer 64

Acidosis, leukemia, lymphoma, corticosteroid treatment, severe burns, immunodeficiencies, dialysis with deferoxamine

Question 65

What is the major clinical form of mucormycosis?

Answer 65

Rhinocerebral mucormycosis

Question 66

What are the symptoms of rhinocerebral mucormycosis?

Answer 66

Edema of the involved facial area, bloody nasal exudate, orbital cellulitis

Question 67

How does thoracic mucormycosis develop?

Answer 67

Inhalation of sporangiospores with invasion of lung parenchyma and vasculature

Question 68

What causes massive tissue destruction in thoracic mucormycosis?

Answer 68

Ischemic necrosis

Question 69

What has thoracic mucormycosis been associated with?

Answer 69

Contaminated wound dressings and other situations

Question 70

What is the colony appearance of Mucorales?

Answer 70

Coarse, wooly, fluffy, white to gray or brown sporangium

Question 71

How fast do Mucorales hyphae grow?

Answer 71

Within 1–3 days, rapidly covering the agar surface

Question 72

What is the characteristic appearance of Rhizopus?

Answer 72

Large, broad, non-septate hyphae that produce horizontal runners (stolons), rhizoids at contact points, and sporangiospores in clusters

Question 73

How does Absidia differ from Rhizopus?

Answer 73

Sporangiospores arise between nodes from which rhizoids are formed

Question 74

What is the defining feature of Mucor?

Answer 74

No rhizoids (root-like structures)

Question 75

What are the key microscopic features of Mucorales?

Answer 75

Broad hyphae (10–15 µm), uneven thickness, irregular branching, sparse septations

Question 76

How do Mucorales colonies grow in culture?

Answer 76

Rapidly, producing abundant cottony colonies

Question 77

What is the basis for identification of Mucorales?

Answer 77

Sporangial structures

Question 78

What are the key treatment strategies for mucormycosis?

Answer 78

Aggressive surgical debridement, rapid administration of amphotericin B, control of underlying disease

Question 79

What residual effects may occur after treatment of rhinocerebral mucormycosis?

Answer 79

Partial facial paralysis or loss of an eye