Fungal infections of the respiratory tract

Question 1

what are the pulmonary fungal infections?

Answer 1

histoplasmosis
coccidioidmycosis
blastomycosis
pneumocystis

Question 2

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

Answer 2

histoplasmosis

Question 3

what are risk factors for histoplasmosis?

Answer 3

bird / bat exposure
building demolition
cave exploring

Question 4

how does histoplasmosis infection occur?

Answer 4

inhalation of mycelia or conidia

Question 5

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

Answer 5

alveolar macrophage

converts to yeast form for hematogenous spread

Question 6

what are the two avenues of histoplasmosis infection?

Answer 6

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

Question 7

what are the symptoms of histoplasmosis?

Answer 7

fever 
chills 
cough 
chest pain 
myalgias 
headache

Question 8

what does histoplasmosis show on PE?

Answer 8

rales

possible consolidation

Question 9

what does imaging show for histoplasmosis?

Answer 9

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

nodes may become calcified

Question 10

histoplasmosis needs to be differentiated from what other condition?

Answer 10

sarcoidosis

Question 11

what are the clinical syndromes associated with histoplasmosis?

Answer 11

acute diffuse pulmonary histoplasmosis (extensive exposure)

chronic pulmonary histoplasmosis (underlying COPD)

Question 12

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

Answer 12

reticulonodular or miliary infiltrates

possible respiratory failure

Question 13

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

Answer 13

fever, chills, chest pain, productive cough

may have apical infiltrates with cavitation

Question 14

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

Answer 14

histoplasmosis

Question 15

what is present on histopathology for histoplasmosis?

Answer 15

granulomas on biopsy 
yeast forms (special stain)

Question 16

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

Answer 16

culture (blood, urine, BAL fluid)

Question 17

what are the medications for histoplasmosis?

Answer 17

amphotericin B
itraconazole
fluconazole
posaconale / voriconazole

Question 18

what are the endemic areas for coccidioidomycosis?

Answer 18

california, arizona, southern nevada

Question 19

what is the pathogenesis of coccidioidomycosis?

Answer 19

1. inhalation of a single arthroconidium

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

Question 20

what is the most common diagnostic test for coccidioidomycosis?

Answer 20

serological testing

Question 21

what is the treatment for coccidioidomycosis - chronic fibrocavitary?

Answer 21

12 months of an azole

Question 22

what is the pathogenesis of blastomycosis?

Answer 22

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

Question 23

what is a major risk factor for pneumocystis?

Answer 23

immunosuppression

Question 24

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

Answer 24

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

ground glass changes

Question 25

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

Answer 25

TMP-SMX