Mycology 2

Question 1

What are the 5 diffrent Aspegillus species that can result in human infections??

Answer 1

Aspergillus fumigatus
A. flavus
A. terreus
A. ustus
A. niger

Question 2

What are the virulance factors of Aspergillus species?

Answer 2

1-High growth rate

2-Small spore size -can penetrate deep lung tissue

3-Hydrophobic coat on conidia - prevents from host defence

4-Ability to adhere to the epithelium

5-Toxin production by few species like A.flavus

Question 3

Which Aspergillus species that is intrinsically resistent to Amphotericin B?

Answer 3

Aspergillus terreus

Question 4

What infcetions that Aspergillus flavus can cause?

Answer 4

1-Sinusitis

2-Invasive disease in immunocompromised patients

Question 5

What infections can Aspergillus niger cause?

Answer 5

Can colonises airways

Can cause otomycosis

Question 6

What is the definition of a Possible IPA?

Answer 6

It is when an Immunosuppressed patients with suggestive radiology (CT) of IPA

Question 7

What is the definition of Probable IPA?

Answer 7

It is a possible IPA plus:

positive direct examination or culture from non-sterile site (sputum/BAL) or:

positive galactomannan and/or PCR

Question 8

What is the definition of a proven IPA?

Answer 8

Positive histopathology or culture from a sterile site and evidence of infection

Question 9

What is Tx Dosing of IPA and target Trough level?

Answer 9

Voriconazole
Loading dose: 6 mg/kg IV q12h for 2 doses
Maintenance: 4 mg/kg IV q12h or 200-300 mg oral q12h
Target trough: 2-5.5 mg/L

Question 10

What are the 2nd line options for Tx of IPA ?

Answer 10

1-Posaconazole (300 mg IV/oral daily)
2-Isavuconazole (200 mg IV/oral daily)
3-Liposomal amphotericin B (3-5 mg/kg/day)
4-Amphotericin B lipid complex (5 mg/kg/day)

Question 11

What is the 1st line Tx of IPA ?

Answer 11

Voriconazole

Question 12

What are the situation where Amphotericin is fisrt line Tx option for IPA instead of Voriconazole?

Answer 12

1-Patients who are on mould-active prophylaxis already

2-Possible mucormycosis

3-Severe chronic liver disease (Child Pugh score C)

4-Documented intolerance of voriconazole (e.g., significant ocular toxicity, neurotoxicity, visual/auditory hallucinations)

5-Patient is on vinca alkaloid

Question 13

what is the required Trough level for Triazoles in treatment of IPA?

Answer 13

Voriconazole: 2-5.5 mg/L
Posaconazole: >1 mg/L

Question 14

IPC measures to reduce risk of Aspergillus spores exposure?

Answer 14

1-HEPA filtration for high-risk patients
2-Positive pressure rooms
3-Avoid construction areas
4-Avoid plants and flowers
5-face Mask during hospital construction
6-Regular air sampling in high-risk units

Question 15

When to start on Empiric antifungals for neutropenic pt whith no diagnosis of fungal infections?

Answer 15

Febrile neutropenic patients (<1.0 x 10⁹/L) unresponsive to broad-spectrum antibacterials for 96 hours

Question 16

What are the IPA high rsk groups requiring prophylaxis?

Answer 16

1-History of prior proven, probable, or possible invasive fungal infection

2-ALL patients receiving induction therapy

3-AML/MDS on intensive chemotherapy

4-Severe/very severe aplastic anaemia

5-Allogeneic stem cell transplant recipients (especially with GVHD)

6-Patients receiving intensive
immunosuppression

Question 17

What is the prophylaxis agent to use in Aspergillus High risk group?

Answer 17

Preferred: Posaconazole or voriconazole

Alternative: Liposomal amphotericin or echinocandin

Question 18

What are the low risk groups of aspergillus infection?

Answer 18

1-Myeloid malignancy with neutropenia
2-Lymphoma with intensive therapy
3-Autologous stem cell transplant
4-Fludarabine in refractory CLL
5-Alemtuzumab use

Question 19

What is the preferred prophylaxis for low risk group?

Answer 19

Oral fluconazole 50mg OD

ALL patients receiving vinca alkaloids: Weekly liposomal amphotericin

Question 20

What are the very low risk conditions for IPA in which prophylaxis is not indicated?

Answer 20

Standard lymphoma therapy
CML with TKIs
Myeloproliferative malignancy
CLL
Non-severe aplastic anemia
ALL maintenance

Question 21

What are the risk groups of ABPA ??

Answer 21

Asthma (common)
cystic fibrosis (common)
bronchiectasis,
chronic granulomatous disease,
hyperimmunoglobulinemia E
lung transplant recipients

Question 22

T/F:

ABPA is type 4 hypersensitivity reaction?

Answer 22

F
It is type 1 immediate
and type 3 immune complex

Question 23

HRCT featchers of ABPA?

Answer 23

1-Central cylindrical bronchiectasis

2-Mucous plugging

3-Ground glass changes with predilection for the upper lobe

Question 24

What are diagnostic criteria of ABPA (ISHAM)?

Answer 24

1- Suggestive clinical picture

2-Mandatory:
#Demonstration of
fungal sensitisation plus:
#Serum total IgE ≥1000 IU/ml (or ≥500 IU/ml if high suspecious ABPA diagnosis , and :

3-Two of the following:
#fungal-specific IgG,
#peripheral blood eosinophilia or
#suggestive imaging.

Question 25

T/F: Aspergillus IgG levels by EIA or lateral flow assay are preferred over Aspergillus serum precipitins.

Answer 25

T

Question 26

What are the virulence factors of cryptococcus spp ?

Answer 26

1-polysaccharide capsule 2-Melanin Production 3-Urease (C. neoformans) 4-Phospholipase (C. gattii)

Question 27

What are the CSF Investigations to consider if suspected CNS Cryptococcosis?

Answer 27

1-CSF opening pressure 2-Glucose 3-Protein 4-Cell counts 5-Microscopy 6-Culture 7-Quantification of CSF cryptococcal antigen

Question 28

Infections that can caused by Cryptococcus spp

Answer 28

1-Pulmonary Cryptococcosis 2-CNS Cryptococcosis 3-Disseminated Cryptococcosis: (skin, bones, eyes and prostate)

Question 29

What are spp of genus cryptococcus?

Answer 29

1-Cryptococcus neoformans (serotypes A and D)- immunocompromised 2-Cryptococcus gattii (serotypes B and C)- immunocompetent

Question 30

What are the possible explanations of false negative CrAg test ?

Answer 30

1-low fungal load 2-Prozone reaction due to high antigen titers (>1:256) 3-Immune complexes preventing antigen shedding 4-Hypocapsular (small levels of capsule) or acapsular strains of Cryptococcus.

Question 31

T/F CrAg test is the most sensitive test for the diagnosis of primary cryptococcal meningitis?

Answer 31

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Question 32

T/F CrAg test can be used as a test of cure for cryptococcus CNS infection?

Answer 32

F it can remain positive for months to years

Question 33

What are the infection that can cause false positive CrAg (<1:8 titre)?

Answer 33

Trichosporon beigelii - (invasive trichosporosis ) Capnocytophaga spp

Question 34

Treatment of pulmonary cryptococcosis (With or without cryptococcoma)?

Answer 34

Fluconazole 400–800 mg daily 6 - 12 months

Question 35

Treatment of cutaneous Cryptococcosis ?

Answer 35

Fluconazole 400 mg daily 3 - 6 months

Question 36

Treatment of CNC/Disseminated Cryptococcosis?

Answer 36

1-Induction Therapy: First-line: Liposomal amphotericin B (3-4 mg/kg/day) + flucytosine (25 mg/kg QID). Alternatives: HD fluconazole (1200 mg daily) + flucytosine. 2-Consolidation Therapy: Fluconazole 400-800 mg daily for 8 week 3-Maintenance Therapy: Fluconazole 200 mg daily for at least 12 months or until immune reconstitution.

Question 37

Indicators of treatment failure in Tx of Cryptococcus meningitis ?

Answer 37

1-Persistent positive CSF cultures after 2 weeks of induction therapy 2-Deterioration of clinical symptoms. 3-Rising CrAg titres.

Question 38

T/F : In Cryptococcus meningitis Tx, recombinant interferon-gamma can be used for refractory cases.

Answer 38

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Question 39

What to Monitor During Treatment of Cryptococcus meningitis ?

Answer 39

Renal Function: Amphotericin B toxicity. Liver Enzymes: Azole therapy hepatotoxicity. CSF Opening Pressure: Frequent lumbar punctures for elevated pressure. Therapeutic Drug Monitoring: Flucytosine levels where available.

Question 40

What are the Steps to take if suspected Tx Failure in Cryptococcus meningitis??

Answer 40

1-Review Adherence 2-Check for Drug Interactions 3-Antifungal Susceptibility Testing 4-Consider Alternative Antifungal Agents (such as voriconazole, posaconazole, or isavuconazole) 5-Repeat Induction Therapy with higher doses 6-Adjunctive Therapies (interferon-gamma for refractory cases)