Fungal Infection Flashcards
(13 cards)
A 43-years old man develops a cough shortly after returning from a 1-month hiking trip in California. He was previously healthy and did not take any medications. He reports a “flu-like” illness consists of fever, cough and muscle pain, which resolved spontaneously. A chest X ray shows a thin-walled cavity in the right upper lobe of the lung, and his sputum reveals fungal elements.
a) Which fungi can cause this lesion?
Coccidioides immitis
اشمعنا هو بالذات؟
This is the causative agent of coccidioidomycosis, also known as Valley Fever, which is endemic in the southwestern United States, especially California and Arizona.
b) How to confirm your choice?
1-Sputum culture
2-Detection of abs by ELISA
3-Histopathology
c) How to treat this disease?
Treatment depends on severity:
1-Mild or self-limited disease: May not require treatment in healthy individuals.
2-Moderate to severe pulmonary disease (e.g., cavitary lesion):
*First-line: Oral azole antifungals:
Fluconazole or Itraconazole for 3–6 months or longer.
*Severe or disseminated disease:
Amphotericin B (especially in pregnant patients or if azoles are contraindica
Other fungi that can cause similar cavitary lung lesions include:
(HABCحبك) أو كحب
1-Histoplasma capsulatum (endemic to the Ohio and Mississippi River valleys)
2-Blastomyces dermatitidis (also Mississippi and Ohio River valleys and Great Lakes)
3-Aspergillus spp. (especially in preexisting cavities, e.g., aspergilloma)
4-Cryptococcus neoformans (rarely causes cavitary lesions, more common in immunocompromised)
Mechanism of action of antifungals
المفتاح
*أهم عنصرين في تكوين cell wall بتاع الفطر هما ergosterol+glucan
*قاعدة SLE
Sequlene
يتحول إلي
Lanosterol
يتحول إلي
ergosterol
هاتهم بقي واحدة واحدة كده
متنساش قاعدة SLE
متنساش قاعدة SLE
1-Allelamine
بيشتغل ازاي؟
بيمنع تحول sequlene الي lanosterol عن طريق انه بيقلل انزيم epoxidase
هاتهم بقي واحدة واحدة كده
متنساش قاعدة SLE
2-Azole
بيشتغل ازاي؟
بيمنع تحويل Lanosterol إلي Ergosterol لأنه بيقلل 14alpha demethylasr
*Uses…CF متنساش
-cryptococcus in hiv…..fluconazole.
-candida… fluconazole
Aspergillus…voriconazole
هاتهم بقي واحدة واحدة كده
متنساش قاعدة SLE
3-Polyene. Macrolides..poresبتاع.. Amphotericin B
بيعمل ايه ؟pores
بيمسك في ergosterol ويعمل pores اخرام فيحصل leakage of ions ويحصل cell death
هاتهم بقي واحدة واحدة كده
متنساش قاعدة SLE
4-Grisoflavin
من اسمه…بتاع gross
*Decrease fungi mitosis.
هاتهم بقي واحدة واحدة كده
متنساش قاعدة SLE
5-Echinocandis
من اسمه
بتاع ايه؟
Inhibit glucan synthesis
بيستخدم في ايه؟
Candida
Aspergillus
امثلة…
ميكو كسب
Caspofungin
Micofungin
Clinical types of aspergillus
1-Aspergilloma (Fungus Ball)
2-Invasive Aspergillosis
3-Disseminated Aspergillosis
4-Cutaneous Aspergillosis
5-Allergic Bronchopulmonary Aspergillosis (ABPA)
6-Chronic Pulmonary Aspergillosis (CPA)
Classification of coccidiomycosis
حرف قبل وحرف بعد
P,D
1-Pulmonary Coccidioidomycosis (Primary Infection):
*This is the most common form and occurs when a person inhales the fungal spores (arthroconidia) from contaminated soil.
*The infection is usually asymptomatic or presents as a mild flu-like illness. However, some individuals develop symptoms like fever, cough, chest pain, and fatigue. In severe cases, it can lead to chronic pulmonary disease, including cavities and fibrosis.
2. Disseminated Coccidioidomycosis:
*This occurs when the infection spreads beyond the lungs to other organs, including the skin, bones, joints, liver, meninges (causing meningitis), and heart.
*Disseminated disease is more likely in immunocompromised individuals, such as those with HIV/AIDS, transplant recipients, or those on immunosuppressive drugs.
Diagnosis of coccidiomycosis
1-Culture:
The gold standard for diagnosis.
2-PCR
3-Elisa to detect abs
4-CFT (Complement Fixation Test)
5-coccidian skin test.
6-Radiological
7-Lumbar puncture in meningitis
