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Questions and Answers
Which of the following is NOT a characteristic of superficial mycoses?
What is the main causative agent of Pityriasis versicolor?
Which of the following dermatophyte fungi is NOT associated with tinea infections?
Which type of tinea infection affects the groin area?
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Which diagnostic method is commonly used for diagnosing dermatophytosis?
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What distinguishes yeast from moulds in their structure?
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Which of the following is a characteristic of dimorphic fungi?
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What is the main component of the cell wall in fungi?
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Which of the following fungi is known for reproducing by budding?
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What is the primary function of the fungal capsule?
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What type of organism are fungi classified as?
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What is the role of spores in moulds?
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Which of the following factors can increase the risk of invasive fungal disease?
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What is the primary characteristic of subcutaneous mycoses?
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What is the most common clinical presentation of sporotrichosis?
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Which method is NOT used for diagnosing sporotrichosis?
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What environmental factors are associated with Histoplasma capsulatum?
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What is a significant risk factor for disseminated sporotrichosis?
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What are common precipitating factors for Candida skin infections?
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How are Candida mucosal infections typically diagnosed?
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What is a key characteristic of Aspergillus as a pathogen?
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Which of the following is NOT a common treatment for Candida infections?
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Which of the following clinical manifestations is associated with Aspergillus infection?
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What is a common symptom of allergic broncho pulmonary aspergillosis?
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Which diagnostic technique is primarily used for identifying fungal infections?
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Which of the following is NOT a risk factor for invasive fungal disease?
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What is the main treatment approach for aspergilloma?
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What is commonly detected in patients with allergic broncho pulmonary aspergillosis?
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What is an essential characteristic of invasive aspergillosis?
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Which method is used for the clinical diagnosis of fungal infection?
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What major complication may arise from underlying lung damage in patients with aspergilloma?
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What factor can precipitate Candida skin infections?
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Which of the following is not a treatment option for Candida infections?
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What is a common clinical manifestation of Aspergillus infection?
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Which of these infections is a possible invasive complication of Candida?
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How are mucosal infections caused by Candida typically diagnosed?
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Which condition is characterized by pale brown or pink macules on the skin, primarily affecting the trunk and neck?
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What is the primary organism responsible for causing tinea infections?
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Which part of the body is affected by tinea capitis?
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Which diagnostic method involves the use of KOH to clear keratin before microscopy?
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Which of the following tinea infections affects the nails?
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What is the primary route of entry for Sporothrix schenckii in cutaneous sporotrichosis?
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Which clinical presentation is most commonly associated with Histoplasma capsulatum infections?
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What is a key diagnostic method for detecting Sporothrix schenckii?
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Which of the following is NOT a risk factor for disseminated sporotrichosis?
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How does Histoplasma capsulatum evade the immune system?
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What is a distinguishing feature of yeast fungi compared to mould?
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Which of the following factors influences whether a dimorphic fungus grows as a yeast or mould?
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What structural component of fungi provides rigidity to the cell wall?
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Which of the following fungi is known for having a unicellular structure?
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What is a primary function of the polysaccharide capsule in certain fungi?
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Which type of fungi primarily comprises clumps of intertwined branching structures?
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Which of the following is NOT a common feature of fungi according to their classification?
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What feature differentiates yeast-like fungi from true yeasts?
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What is the primary symptom of allergic broncho pulmonary aspergillosis?
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Which imaging finding is characteristic of an aspergilloma?
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What is the first-line treatment for invasive aspergillosis?
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Which of the following is NOT typically a risk factor for invasive fungal disease?
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What laboratory assessment is commonly used to diagnose allergic broncho pulmonary aspergillosis?
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Which diagnostic technique is specifically mentioned as part of the assessment for fungal infections?
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What is a common laboratory finding in patients with aspergilloma?
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Which statement best describes the nature of invasive aspergillosis?
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Which of the following conditions is characterized by an itchy, patchy rash primarily on the trunk and neck?
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Which genus of dermatophyte is associated with tinea infections affecting the skin?
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What is the primary method used to confirm dermatophytosis after initial clinical diagnosis?
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Which statement accurately describes the dermatophyte infections known as tinea?
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Which method is primarily used for the diagnosis of pityriasis versicolor?
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What distinguishes the clinical presentations of sporotrichosis from other fungal infections?
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Which environmental factor is most closely associated with the presence of Histoplasma capsulatum?
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What is the primary reason for the difficulty in diagnosing Histoplasma capsulatum infections?
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What role do pre-existing health conditions play in the severity of sporotrichosis?
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Which method of diagnosis for sporotrichosis provides the fastest results?
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What is the primary diagnostic technique for mucosal infections caused by Candida?
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Which condition is NOT considered a part of invasive Candida infections?
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Which clinical manifestation is typically associated with allergic aspergillosis?
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What is a common factor that can trigger Candida skin infections?
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What type of fungus is Aspergillus primarily classified as?
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Which structural component is found in the cell membrane of fungi that differentiates them from bacterial cells?
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What is the primary characteristic that differentiates dimorphic fungi from other types of fungi?
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Which type of fungus primarily reproduces through the production of spores?
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Which of the following accurately describes hyphae in moulds?
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What role does the fungal capsule play in pathogenicity?
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Which of the following fungi can have both yeast and filamentous forms?
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What feature of fungal spores distinguishes them in terms of their reproductive function?
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Which of the following accurately describes the general classification of fungi?
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What laboratory technique is most consistently used for diagnosing fungal infections in clinical settings?
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Which of the following populations has the highest risk for developing invasive aspergillosis?
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What is the typical clinical presentation of allergic broncho pulmonary aspergillosis?
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What is the common imaging finding in patients with aspergilloma?
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In allergic broncho pulmonary aspergillosis, which blood test result is commonly elevated?
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Which of the following is a contraindication for using antifungal agents in aspergilloma treatment?
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Which diagnostic method relies on observing fungal elements directly from a patient sample?
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In patients with invasive aspergillosis, which organ is least likely to be affected by the spread of the infection?
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Study Notes
Fungi
- Eukaryotic organisms
- Found worldwide, some are endemic to specific regions
- Exist as non-pathogenic, primary pathogens, and opportunistic pathogens
- Not susceptible to antibiotics
- Can be classified into yeast, mould, and dimorphic
Fungal Structure
-
Cell Membrane:
- Phospholipid bilayer
- Surrounds cytoplasm
- Contains Ergosterol
-
Cell Wall:
- Composed of chitin and carbohydrates (ß-d-glucan and mannans)
- Provides rigidity
- Antigenic
-
Capsule:
- Present in some fungi
- Polysaccharide
- Antiphagocytic virulence factor
Yeast
- Unicellular, spheroid or ellipsoid
- Reproduce by budding
- Moist, mucoid, or waxy colonies
Yeast-Like Fungi (e.g., Candida Albicans )
- Grow as both yeast and elongated hyphae (pseudohyphae)
- Reproduce by budding
- Generally creamy white colonies
Mould or Filamentous Fungi
- Multicellular
- Composed of intertwined branching hyphae
- Grow by longitudinal extension
- Produce spores
Dimorphic Fungi
- Can grow as yeast or mould depending on environmental temperature:
- Moulds in the environment at 25-30°C
- Yeasts in human tissues at 35-37°C
Fungal Infections: Importance & Types
-
Increasing Cases: Result of vulnerable patients undergoing chemotherapy, transplantation, and immunomodulatory therapies
-
Better Manageability: Improved diagnostic techniques and new anti-fungal agents
-
Types of fungal infections:*
-
Superficial: Limited to outermost layers of skin, hair, nails, and mucosa
-
Invasive: Infections involving deeper layers of cutaneous tissues, subcutaneous tissue, and systemic spread
Superficial Mycoses
-
Pityriasis Versicolor:
- Caused by Malassezia furfur (filamentous fungus)
- Presents as patchy rash with pale brown/pink macules and pale patches (common in darker skin)
- Itchy, commonly affecting the trunk and neck
- More prevalent in hot, humid climates
- Diagnosed by clinical appearance, Wood's Light examination, and skin scrapings
-
Dermatophytosis (Ringworm/Tinea):
- Skin infections caused by dermatophyte fungi
- Three genera of dermatophytes: Trichophyton spp, Epidermophyton spp, and Microsporum spp
- Acquired from humans, animals, or soil
- Location of infection dictates the Tinea type (e.g., Tinea capitis (head), Tinea pedis (foot), Tinea unguium (nail))
- Diagnosed by clinical appearance, skin scrapings/nail clippings, microscopy (using KOH), and culture on selective media (Sabouraud agar)
Subcutaneous Mycoses
-
Sporotrichosis (Rose Pickers Disease):
- Caused by Sporothrix schenckii (dimorphic fungus)
- Initial ulcer develops into granulomatous nodule
- Acquired at sites of trauma from contaminated soil or thorns
-
Clinical Spectrum:
- Cutaneous/Lymphocutaneous: Most common, enters through skin breaks, commonly affecting the hand
- Pulmonary: Inhalation of fungal spores
- Disseminated: Spread to other organs (e.g., osteoarticular, CNS), risk factors include immunosuppression, COPD, HIV, alcohol excess
- Diagnosis:
- Microscopy (KOH), Culture (Sabouraud agar), Histopathology, tissue biopsy, sputum, and body fluids
Dimorphic Fungal Infection – Histoplasma Capsulatum
- Grows as moulds at 25°C and yeasts at 37°C
- Not prevalent in Ireland, UK, or Europe, but found in North America
- Found in soil, bird/bat guano, and caves
-
Clinical Presentation:
- Asymptomatic
- Acute/chronic respiratory infections mimicking TB
- Disseminated infections (liver, lungs, spleen) in immunosuppressed patients
- Fungus lives intracellularly in macrophages, evading the immune system
-
Diagnosis:
- Antigen detection (urine, serum)
- Culture (tissue, blood body fluid)
- Histopathology
- Microscopy
- Serology
Candida
- Normal flora in the mouth, intestine, and lower genital tract
- Opportunistic pathogen
- Causes superficial (skin, mucosal) and systemic infections
Candida - Skin Infections
- Presents with erythrema, plaque-like lesions, satellite lesions
- Found in warm, moist areas, skin folds (intertrigo)
- Precipitated by antibiotics, steroids, pregnancy, and immunosuppression
- Diagnosis: Clinical appearance, skin scrapings, swabs
- Treatment: Topical Antifungal agents (Clotrimazole), Oral antifungals (Fluconazole)
Candida - Mucosal Infections
- Discrete white patches on mucosal surfaces (oral, vaginal, oesophageal (especially in HIV))
- Diagnosis: Swabs for microscopy and culture
- Treatment: Topical antifungals (Clotrimazole), Oral antifungals (Fluconazole)
Candida - Invasive Infections
- Candida bloodstream infection
- Infective endocarditis
- Peritonitis
- Osteomyelitis
- Arthritis
- Endophthalmitis
Aspergillus
- Mould/filamentous fungus
- Found in soil, air, plants, and decomposing organic matter
- Common in hospital environments
- Pathogenesis:
- Allergy: Reaction to Aspergillus antigens (ABPA)
- Spore-forming: Spores inhaled, germinate into hyphae, destruct blood vessels, and disseminate
Aspergillus - Clinical Manifestations
- Allergic Aspergillosis: Sinusitis, Allergic Bronchopulmonary Aspergilliosis (ABPA)
- Aspergilloma: Found in damaged lungs (TB, CF, COPD)
- Invasive Aspergillosis: Risk groups: neutropenia, transplants, HIV, Spread from primary site to other organs (liver, spleen, kidney, CNS)
Allergic Bronchopulmonary Aspergilliosis (ABPA)
- Hypersensitivity reaction, common in patients with asthma or cystic fibrosis
- Presents with bronchospasm, obstruction, wheeze, cough, shortness of breath, fever
- Diagnosed by high antibody titres in serum with fleeting CXR changes and eosinophilia with high IgE levels
- Treatment: Steroids and/or Itraconazole
Aspergilloma
- Found in damaged lungs
- May be asymptomatic, but can cause chronic cough and hemoptysis
- Diagnosed by sputum, antibodies and CXR/CT Thorax findings
- Treatment - Surgery in some cases, no role for antifungals
Invasive Aspergillosis
- Risk groups: neutropenia, transplantation, HIV
- Spread from primary site to other organs (liver, spleen, kidney, CNS)
- Invades blood vessels
Diagnostic Techniques
- Diagnosis: Based on clinical presentation, examination, and additional testing
- Techniques: Clinical diagnosis, microscopy and culture, antigen detection, serology, histopathology, radiology
Risk Factors for Invasive Fungal Infection
- Haematological malignancy
- Haematopoietic stem-cell transplant
- Solid organ transplant
- Neutropenia
- Extremes of age
- Abdominal surgery
- Prolonged ICU admission
- Central venous catheter
- Broad-spectrum antibiotics
- Renal failure
Fungi
- Eukaryotic organisms
- Can be harmless, primary pathogens, or opportunistic pathogens
- Not susceptible to antibiotics
Fungal Structure
- Cell membrane: phospholipid bilayer surrounding cytoplasm, contains ergosterol
- Cell wall: composed of chitin, β-d-glucan, and mannans, provides rigidity, acts as an antigen
- Capsule: present in some fungi, composed of polysaccharide, prevents phagocytosis by immune cells
Classification of Fungi
- Yeast: unicellular, reproduces by budding
- Mould (Filamentous Fungi): multicellular, composed of branching hyphae, grows by extending hyphae, produces spores
- Dimorphic: can grow as either yeast or mould depending on environmental conditions and temperature
Some Definitions
- Hyphae: tubules made up of fungal cells linked end-to-end, grow from the tip of the tubules
- Spores: reproductive bodies of moulds
Importance of Fungal Infections:
- Increasing number of vulnerable patients (e.g., chemotherapy, transplantation, immunomodulatory therapies)
- Improved diagnostic techniques and new antifungal agents make fungal infections more manageable
Types of Fungal Infections
- Superficial: limited to outermost skin layers, hair, nails, and mucosa
-
Invasive:
- Subcutaneous: involves deeper layers of dermis and subcutaneous tissue
- Systemic: affects internal organs
Superficial Mycoses
- Pityriasis Versicolor: caused by Malassezia furfur, characterized by patchy rash, pale brown/pink macules, or pale patches, most common on the trunk and neck
- Dermatophytosis (Ringworm/Tinea): skin infection by dermatophyte fungi (Trichophyton spp, Epidermophyton spp, Microsporum spp), acquired from humans, animals, or soil
- Candidiasis: discussed in later lectures
Pityriasis Versicolor
- Diagnosis: clinical appearance, Wood’s Light, skin scrapings
Tinea (Ringworm)
- Infection site dictates the name (e.g., Tinea barbae, Tinea capitis, Tinea pedis)
- Diagnosis:
- Clinical appearance
- Skin scrapings/nail clippings
- Microscopy (KOH prep), culture on Sabouraud agar
Subcutaneous Mycoses
- Involves deeper layers of skin, acquired from contaminated soil or thorns
Sporotrichosis (‘Rose Picker’s Disease)
- Caused by Sporothrix schenckii, initial ulcer progresses into granulomatous nodule
Sporotrichosis Clinical Spectrum:
- Cutaneous/Lymphocutaneous: most common, enters through a skin break from contact with contaminated plant matter
- Pulmonary: inhalation of fungal spores
-
Disseminated: spread to other body parts (e.g., osteoarticular, central nervous system)
- Risk factors: Immunodeficiency, COPD, HIV, alcohol excess
Sporotrichosis Diagnosis
- Microscopy (KOH prep)
- Culture (tissue biopsy, sputum, body fluid)
- Histopathology
Histoplasma capsulatum
- Dimorphic fungus: mould at 25°C, yeast at 37°C
- Found in soil, bird/bat guano, caves
- Can be asymptomatic or cause respiratory infection mimicking TB
- Disseminated infection in immunosuppressed individuals
- Lives intracellularly in macrophages, evading the immune system
Histoplasma capsulatum Diagnosis
- Antigen detection (urine/serum)
- Culture (tissue, blood, body fluids)
- Histopathology
- Microscopy (low sensitivity)
- Serology
Candida
- Normal flora in mouth, intestine, and lower genital tract
- Opportunistic pathogen with increasing importance
- Causes superficial (skin, mucosa) and systemic infections
Candida Skin Infections
- Erythema, plaque-like lesions, satellite lesions
- Occur in warm, moist areas, skin folds (intertrigo)
- Precipitants: antibiotics, steroids, pregnancy, immunosuppression
Candida Skin Infection Diagnosis and Treatment
- Diagnosis: clinical appearance, skin scrapings, swabs
- Treatment: topical antifungal agents (clotrimazole), oral fluconazole
Candida Mucosal Infections
- Discrete white patches on mucosal surfaces (mouth, vagina, esophagus)
- Diagnosis: swabs for microscopy and culture
- Treatment: topical (clotrimazole), oral antifungal (fluconazole)
Candida Invasive Infections
- Candida bloodstream infection
- Infective endocarditis
- Peritonitis, osteomyelitis, arthritis, endophthalmitis
- Discussed in detail in the Introduction to Opportunistic Infections lecture
Aspergillus
- Mould (filamentous fungus)
- Found in soil, air, plants, decomposing organic matter
- Common in hospital environments (construction work)
Aspergillus Pathogenesis
- Allergy: reaction to Aspergillus antigens in atopic individuals (Allergic Bronchopulmonary Aspergillosis - ABPA)
- Spore-forming: spores inhaled, germinate into hyphae, damage blood vessels, and disseminate
Aspergillus Clinical Manifestations:
- Allergic Aspergillosis: sinusitis, Allergic Bronchopulmonary Aspergillosis (ABPA)
- Aspergilloma: fungal ball in damaged lung
- Invasive Aspergillosis: invades blood vessels and spreads to other organs, discussed in the Introduction to Opportunistic Infections lecture
Allergic Bronchopulmonary Aspergillosis (ABPA)
- Hypersensitivity reaction, common in asthmatics and cystic fibrosis patients
- Bronchospasm, obstruction, wheezing, coughing, shortness of breath, fever
- Eosinophilia, high IgE, high antibody titres in serum
- Fleeting chest X-ray changes
- Treatment: steroids +/- itraconazole
Aspergilloma
- Occurs in damaged lungs (TB, CF, COPD)
- Asymptomatic, chronic cough, hemoptysis
- Sputum positive in 66%, antibodies positive in 70%, fluid-filled cavity on CXR/CT
- Surgery in some cases, no role for antifungals
Invasive Aspergillosis
- Risk groups: neutropenia, transplant, HIV
- Spread from primary site to other organs (liver, spleen, kidney, CNS)
- Invades blood vessels
- Discussed in detail in Introduction to Opportunistic Infections lecture
Diagnostic Techniques for Fungal Infections:
- Clinical presentation
- Microscopy and culture
- Antigen detection
- Serology
- Histopathology
- Radiology
Risk Factors for Invasive Fungal Infections:
- Hematological malignancy
- Hematopoietic stem cell transplant
- Solid organ transplant
- Neutropenia
- Extremes of age
- Abdominal surgery
- Prolonged ICU admission
- Central venous catheter
- Use of broad-spectrum antibiotics
- Renal failure
Summary
- Covered yeast, moulds, and dimorphic fungi
- Detailed classification, morphology, and pathogenicity of fungi
- Explored superficial, subcutaneous, and systemic fungal infections
- Discussed Candida and Aspergillus infections
- Treatment of fungal infections will be covered in the antifungal/antiviral lecture
- Invasive fungal infections will be covered in the Introduction to Opportunistic Infections lecture.
Fungi
- Fungi are eukaryotes
- Fungi are found globally, some fungi are endemic to specific locations
- Fungi can be non-pathogenic, primary pathogens, or opportunistic pathogens
- Fungi are not susceptible to antibiotics
Fungal Structure
- Cell membrane: phospholipid bilayer, surrounds cytoplasm, contains ergosterol
- Cell wall: chitin and carbohydrates (β-d-glucan, mannans), chitin provides rigidity, antigenic
- Capsule: present in some fungi, polysaccharide, antiphagocytic virulence factor
Classification of Fungi
- Yeast: unicellular (spheroid or ellipsoid), reproduce by budding, moist, mucoid, or waxy colonies
- Yeast-like Fungi (e.g. Candida albicans): grow partly as yeast and partly as elongated cells resembling hyphae (pseudohyphae), reproduce by budding, generally creamy white colonies
- Mould or filamentous Fungi: multicellular, made up of clumps of intertwined branching hyphae, grow by longitudinal extension, produce spores
- Dimorphic Fungi: grow either as yeast or mould depending on environmental conditions and temperature (moulds in environment at 25-30°C, yeasts in human tissues at 35-37°C)
Terms
- Hyphae: tubules made up of fungal cells attached end to end, growth occurs by extending in length from the tip of the tubules
- Spores: reproducing bodies of moulds
Why is Fungal Infection Important?
- More Cases: increasing number of vulnerable patients (chemotherapy, transplantation, immunomodulatory therapies)
- More Manageable: better diagnostic techniques, new anti-fungal agents available
Types of Fungal Infection
- Superficial: limited to outermost layers of skin, hair, nails, and mucosa
-
Invasive: involves deeper layers of tissue
- Subcutaneous: involves deeper layers of the dermis and subcutaneous tissue
- Systemic: spread throughout the body
Superficial Mycoses
-
Pityriasis versicolor: caused by Malassezia furfur (filamentous fungus), common patchy rash (pale brown/pink macules), more common in hot, humid climates
- Diagnosis: clinical appearance, Wood's Light, skin scrapings
-
Dermatophytosis (Ringworm/Tinea): skin infection caused by dermatophyte fungi (three genera: Trichophyton spp, Epidermophyton spp, Microsporum spp).
- Acquired from humans, animals, or soil
- Location of the infection determines the specific name of the infection (e.g. Tinea barbae - beard, Tinea capitis - head, etc.)
- Diagnosis: clinical appearance, skin scrapings/nail clippings, microscopy (KOH), culture on selective media (Sabouraud agar)
Subcutaneous Mycoses
- Involves deeper layers of the dermis and subcutaneous tissue
- Acquired from soil or thorns at sites of trauma
Sporotrichosis ('Rose Picker's Disease)
- Caused by Sporothrix schenckii (dimorphic fungus)
- Initial ulcer develops into a granulomatous nodule
-
Clinical Spectrum:
- Cutaneous/Lymphocutaneous: Most common, enters through a break in the skin from contaminated plant matter
- Pulmonary: Inhalation of fungal spores
- Disseminated: Spread to other parts of the body (e.g. osteoarticular, central nervous system), risk factors include immunodeficiency, COPD, HIV, excessive alcohol consumption
- Diagnosis: microscopy (KOH), culture (Sabouraud agar - tissue biopsy, sputum, body fluid), histopathology
Dimorphic Fungal Infection - Histoplasma capsulatum
- Grows as a mould at 25°C and a yeast at 37°C
- Found in soil, bird/bat guano, caves
-
Clinical Presentation:
- Asymptomatic infection
- Acute/Chronic respiratory infection resembling TB
- Disseminated, involving liver, lungs, spleen (in immunosuppressed patients)
- Diagnosis: antigen detection (urine/serum), culture (tissue, blood, body fluid), histopathology, microscopy (low sensitivity), serology
Candida (Pseudoyeasts)
- Normal flora: mouth, intestine, and lower genital tract
- Opportunistic pathogen (increasing importance)
- Superficial (skin and mucosal) and Systemic Infections
Candida - Skin Infections
- Clinical Features: Erythema, plaque-like lesions, satellite lesions, warm, moist areas, skin folds
- Precipitants: antibiotics, steroids, pregnancy, immunosuppression
- Diagnosis: clinical appearance, skin scrapings, swabs
- Treatment: topical antifungal agents (clotrimazole), oral fluconazole
Candida - Mucosal Infections
- Clinical Features: Discrete white patches on the mucosal surface (oral, vaginal, oesophageal (especially in HIV patients))
- Diagnosis: swab for microscopy and culture
- Treatment: topical (clotrimazole), oral antifungal (fluconazole)
Candida - Invasive Infections
- Candida bloodstream infection, infective endocarditis, peritonitis, osteomyelitis, arthritis, endophthalmitis
Aspergillus
- Mould/Filamentous fungus
- Found in soil, air, plants, decomposing organic matter
- Common in hospital environments (construction work)
Aspergillus - Pathogenesis
- Allergy: due to reaction to Aspergillus antigens in atopic individuals (Allergic Bronchopulmonary Aspergillosis - ABPA)
- Spore-forming Organism: spores are inhaled, germinate to form hyphae, destruct blood vessels and disseminate
Clinical Manifestations of Aspergillus
- Allergic Aspergillosis: sinusitis, Allergic Bronchopulmonary Aspergillosis (ABPA)
- Aspergilloma
- Invasive Aspergillosis
Allergic Bronchopulmonary Aspergillosis (ABPA)
- Hypersensitivity reaction, common in asthma and cystic fibrosis patients
- Clinical Features: Bronchospasm, obstruction, wheeze, cough, shortness of breath, fever
- Diagnosis Eosinophilia, high IgE, high antibody titres in serum, fleeting CXR changes
- Treatment: steroids +/- itraconazole
Aspergilloma
- Occurs in damaged lungs (TB, CF, COPD)
- Clinical Features: asymptomatic, chronic cough, haemoptysis
- Diagnosis: sputum positive in 66% of cases, antibodies positive in 70% of cases, fluid-filled cavity on CXR/CT Thorax
- Treatment: surgery in some cases, no role for antifungals
Invasive Aspergillosis
- Risk Groups: neutropenia, transplant patients, HIV
- Clinical Features: spread from primary site to other sites (liver, spleen, kidney, CNS), invasion of blood vessels
Diagnostic techniques for Fungal Infections
- Clinical diagnosis
- Microscopy and Culture
- Antigen detection
- Serology
- Histopathology
- Radiology
Risk Factors for Invasive Fungal Infection
- Haematological malignancy
- Haematopoietic stem-cell transplant
- Solid organ transplant
- Neutropenia
- Extremes of age
- Abdominal surgery
- Prolonged ICU admission
- Central venous catheter
- Use of broad-spectrum antibiotics
- Renal failure
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Description
Test your knowledge on the various types of fungi, their structures, and characteristics in this detailed quiz. From eukaryotic organisms to unicellular yeasts and multicellular moulds, explore the essential features and classifications of fungi. Perfect for students studying microbiology or related fields.
