Question
The fungus shown in the image is a Filamentous fungus,with septate hyphae branching at acute angles, and mode of transmission is through inhalation of conidia.It causes all of the following diseases except?
A. Bronchopulmonary allergy.
B. Otomycosis.
C. Dermatophytosis.
D. Sinusitis.
Show Answer
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Correct Answer » C Explanation |
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Ans: C. Dermatophytosis.
The fungus shown in the picture above represents Aspergillus.
Aspergillus.
- Aspergillus fumigatus is the species most commonly implicated.
- Aspergillus fumigatus, a saprophytic fungus, can opportunistically cause a multitude of diseases in humans.
- It primarily lives in soil and decaying vegetation, can be dispersed through the air as asexual spores, known as conidia. Because of this, humans usually get infected with the fungus by inhaling these conidia.
Morphology:
- Monomorphic Filamentous Fungi.Dichotomously Branching.Genrally acute angles.Hyphae are septate with smooth walled conidiophores . Vesicles are subclavate in shape.Conidiogenous cells (phialides) are flask shaped, uniseriate, compact (closely spaced), usually forming on the upper two-thirds of the vesicle and mature parallel to the axis of the conidiophore (columnar formation). Young conidial heads may radiate. Conidia are verrucose (smooth or slightly rough), (sub)spherical and develop in chains.
Clinical manifestations of aspergillosis
- Allergic bronchopulmonary aspergillosis occurs in patients with preexisting asthma or cystic fibrosis.
- Endobronchial saprophytic pulmonary aspergillosis (Aspergilloma) in a patient with prior chronic lung disease, such as tuberculosis, sarcoidosis, bronchiectasis or histoplasmosis.
- Invasive aspergillosis develops as an acute pneumonic process with or without dissemination in the immunocompromized patients (most common among patients with acute leukemia and recipient of tissue transplants. – CT finding —> Halo sign and crescent sign
Allergic sinusitis may take three forms :
- A fungal ball may form.
- Chronic fibrosing granulomatous inflammation
- Allergic fungal sinusitis
Aspergillosis in AIDS
- Most commonly infect lung
- CD4 + cell count is < 50/ L
Extrapulmonary
- Otomycosis , Endophthalmitis,Keratitis , Endocarditis
