Fungal infections of the respiratory tract Flashcards Preview

Year 2 Respiratory > Fungal infections of the respiratory tract > Flashcards

Flashcards in Fungal infections of the respiratory tract Deck (25)
1

what are the pulmonary fungal infections?

histoplasmosis
coccidioidmycosis
blastomycosis
pneumocystis

2

what is the most common endemic fungal infection in the US?

histoplasmosis

3

what are risk factors for histoplasmosis?

bird / bat exposure
building demolition
cave exploring

4

how does histoplasmosis infection occur?

inhalation of mycelia or conidia

5

where do the histoplasmosis microconidia survive in the host? what occurs then?

alveolar macrophage

converts to yeast form for hematogenous spread

6

what are the two avenues of histoplasmosis infection?

1. cell mediated immunity controls infection, leaves calcified nodules in lung, spleen
2. dissemination leading to infection occurs in large inocula, immunocompromised

7

what are the symptoms of histoplasmosis?

fever
chills
cough
chest pain
myalgias
headache

8

what does histoplasmosis show on PE?

rales
possible consolidation

9

what does imaging show for histoplasmosis?

hilar and mediastinal lymphadenopathy with focal infiltrates which are patchy or nodular in appearance

nodes may become calcified

10

histoplasmosis needs to be differentiated from what other condition?

sarcoidosis

11

what are the clinical syndromes associated with histoplasmosis?

acute diffuse pulmonary histoplasmosis (extensive exposure)

chronic pulmonary histoplasmosis (underlying COPD)

12

what is seen with acute diffuse pulmonary histoplasmosis (extensive exposure)?

reticulonodular or miliary infiltrates
possible respiratory failure

13

what is seen with chronic pulmonary histoplasmosis (underlying COPD)?

fever, chills, chest pain, productive cough
may have apical infiltrates with cavitation

14

what should be considered in a fungal disease with erythema nodosum / multiforme?

histoplasmosis

15

what is present on histopathology for histoplasmosis?

granulomas on biopsy
yeast forms (special stain)

16

what is the most useful diagnostic test for histoplasmosis? what types of specimen?

culture (blood, urine, BAL fluid)

17

what are the medications for histoplasmosis?

amphotericin B
itraconazole
fluconazole
posaconale / voriconazole

18

what are the endemic areas for coccidioidomycosis?

california, arizona, southern nevada

19

what is the pathogenesis of coccidioidomycosis?

1. inhalation of a single arthroconidium
2. in the lung the barrel shaped arthroconidium changes to a spherical structure which ruptures to release endospores

20

what is the most common diagnostic test for coccidioidomycosis?

serological testing

21

what is the treatment for coccidioidomycosis - chronic fibrocavitary?

12 months of an azole

22

what is the pathogenesis of blastomycosis?

systemic pyorgranulomatous infection due to inhalation of mycelial conidia of blastomyces dermatiditis

23

what is a major risk factor for pneumocystis?

immunosuppression

24

how does pneumocystis present in non-HIV patients? what are the CT findings?

fulminant respiratory failure with progression of bilateral infiltrates after 1-2 days

ground glass changes

25

what is the best treatment for pneumocystis in non-HIV patients?

TMP-SMX