Clinical Aspects of Respiratory Infection Flashcards
What’s the most common, new symptomatic presentation of HIV?
Pneumocystis pneumonia
What organism is responsible for Histoplasmosis infection?
Histoplasmosis
- Fungus: Histoplasma capsulatum
- soil and bat or bird poo -> disrupted soil may release infectious elements that can
be inhaled into the lungs
- common in immunocompromised patients
(e. g. HIV)
Pathophysiology of Histoplasmosis
When inhaled into the alveoli, they can survive phagocytosis -> in fact the phagocyte (that engulfed fungi) is a place where fungi multiply -> as macrophages travel in lymphatic circulation -> potential to spread to other organs
Symptoms of histoplasmosis
A. Acute phase: non-specific respiratory symptoms (cough, flu-like); chest X ray is normal in
40-70% of cases
B. Chronic histoplasmosis -> similar to TB
Possible complications of Histoplasmosis
occur if treatment is not provided, especially in immunocompromised patients:
- recurrent pneumonia
- respiratory failure
- fibronising mediastinitis -> serious complication, may be fatal
- superior vena cava syndrome
- pulmonary vessel obstruction
- progressive fibrosis of lymph nodes
Diagnosis of Histoplasmosis
- samples containing fungus taken from sputum, blood or infected organs
- ELISA or PCR -> detection of antigen in blood or urine samples
- Blood test -> antibodies against Histoplasma
- Histoplasma skin tests -> indicate if a person has been exposed (but not able to tell if a person
has the disease)
Treatment of Histoplasmosis
- immunocompetent individuals -> infection resolves on its own
- severe infection (severe cases of acute histoplasmosis and ALL cases of disseminated histoplasmosis) -> anti-fungal medication: Amphotercin B -> followed by itraconazole
*itraconazole treatment needs to continue for at least a year in severe causes
But in acute pulmonary histomatosis -> 6 - 12 weeks of treatment is usually sufficient
Individuals taking itraconazole should be monitored in view of hepatic function
What is the arrow pointing at?
- the cavity on the top of the lung -> perhaps TB (or other caveating lung infections)
- (cavity identified as darker spot with white borders -> where the arrow points)
What’s ground glass appearance?
‘Grand glass shadowing’ -> multiple flu -> patchy areas = acute inflammation in the lungs -> caused by
infections
Treatment of pulmonary TB