Classical case explaining lung infection with hemoptysis. ?

UP CHO - 2018

Applied Microbiology & Infection control

Medium

Appeared in: UP CHO - 2018

Explanation

Aspergillus is a fungus known to cause a variety of lung infections, including aspergilloma ('fungus ball'), which classically presents with hemoptysis (coughing up blood).
The definitive microscopic feature of Aspergillus species is the presence of septate hyphae, which are fungal filaments divided by internal cross-walls (septa).
These septate hyphae characteristically branch at acute angles, typically around 45 degrees.

Option A: This is incorrect because a defining characteristic of Aspergillus is its septate hyphae (filaments with cross-walls), not aseptate.
Option C: This is incorrect. Rhizopus, a fungus belonging to the order Mucorales, is characterized by broad, aseptate (or pauciseptate) hyphae, not septate hyphae.
Option D: This is incorrect. Mucormycosis is caused by fungi of the order Mucorales (e.g., Mucor, Rhizopus), which are defined by their broad, ribbon-like, aseptate (non-septate) hyphae that branch at right angles.

Clinical Relevance

Nursing practice connection: Knowing Identification of fungal pathogens based on microscopic morphology and clinical presentation helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Accurate identification of the fungal pathogen is critical for guiding appropriate antifungal therapy. Aspergillosis is typically treated with voriconazole, while mucormycosis requires aggressive treatment with amphotericin B.
Nurses should be aware that patients with pre-existing lung cavities (from TB, bronchiectasis) are at higher risk for developing aspergillomas and should be monitored for hemoptysis.
What if? If the patient was a diabetic with ketoacidosis and presented with black necrotic tissue in the nose, the primary suspicion would shift to rhinocerebral mucormycosis, and the expected microscopic finding would be broad, aseptate hyphae branching at 90 degrees.

How to Approach the Question

First, identify the key clinical information in the stem: 'lung infection' and 'hemoptysis'.
Recognize that hemoptysis in the context of a chronic lung infection strongly suggests an aspergilloma (fungus ball).
Recall the basic microscopic morphology of common pathogenic fungi.
Evaluate each option against the known characteristics of Aspergillus. Remember that Aspergillus has septate hyphae and branches at acute angles.
Eliminate the options that incorrectly describe the morphology of the named fungi (e.g., Rhizopus with septate hyphae, Mucormycosis with septate hyphae).
Select the option that correctly pairs the fungus (Aspergillus) with its characteristic morphology (septate branching).

Concept Tested & Keywords

Concept Tested: Identification of fungal pathogens based on microscopic morphology and clinical presentation.
Stem keywords: lung infection, hemoptysis
Lead-in keywords: Classical case
Clinical cues: Hemoptysis is a key clinical sign pointing towards aspergilloma, a common form of aspergillosis.

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E6 Pathology- ROBBINS & COTRAN PATHOLOGIC BASIS OF DISEASE 10TH Ed p. 394-396

E6 Pathology-Textbook of PATHOLOGYHarsh Mohan Part 2 (215-514) p. 48-50