Fungal Pulmonary Disease

Question 1

Dimorphic
Yeast only
Hyphae only
Neither

Answer 1

Dimorphic - histo, blasto, coccidio…yeast in host and mycelia in nature

YEast only - cryptococucs, candida

Hyphae only - aspergillus or mucormycosis

Neither - pneumocystis

Question 2

Patho of dimorphic fungi

Answer 2

CMI is important and will show granulomas

Non-infectious granuloma does NOT rule out dimorphic fungi

Neither does absence of yeast forms through silver stain

Question 3

Hyphae pathology

Answer 3

Phagocytic function is much more important

Tissue sections show necrotic tissue bc organisms are angioinvasive

Aseprgillus - 45 deg

Mucor - 90 dfegree

Question 4

Histoplasmosis

Answer 4

Endemic to our region

Dimorphic

Soil organism

Outbreaks follow excavation or bird roost exposure

Initial infection subclinical like TB and Blastomycosis with early dissemination and control

Splenic calcifications show resolved

If acute sx, 7-21 days after incubation and mimic influenza

Question 5

Acute inhalational

Chronic cavitary histo

Answer 5

Mimics influenza…may produce buckshot CXR

Mimics calssic TB and favors men with COPD…smoking cessation and itraconazole

Question 6

Disseminated
Mediastinal
Histoplasmoma

Answer 6

Miliary pattern on radiograph

Unique among fungi…adenopathy…differentiate from actue adenitis

Commonest cause of benign lung nodule in KY

Question 7

Blastomycosis

Answer 7

Dimorphic

Symptomatic in only 50% (30-45 day incubation)

Maybe near rivers?

Skin lesions with heaped-up or ulcerated appearance

Fungus mimics cancer (borad based budding yeast)

Question 8

Pneumocystis pneumonia

Answer 8

Profound CMI

Dry cough, fever, dyspnea

Radiograph should airspace infiltrates and pneumatoceles…GGO that can cause pneumothorax

Different than most fungal dzs in tx

Question 9

Infectious comps in HIV

Answer 9

Pneumocystis rare if CD4 above 200

Bactrim is good prophylaxis

Question 10

Coccidiomycosis

Answer 10

Dimoprihc in SW US

Primary infection 7-21 days after exposure…triead of fever, erythema nodosum, and arthralgia

Looks like communicty acquired pnuemonia

May get overwhelimg infection with resp failure and sepctic shock

Dx by serology or spherules

Beware lab cultures but can’t transmit person to perosn

Question 11

Invasive aspergillosis

Chronic necrotizing aspergillosis

Answer 11

Hematogenous spread in pro,onged neutropenia (lung transplant, leukemia)…patients with prolonged fever

Structural lung dz and locally impaired immunity (emphy, silicosis)…looks and acts like TB

Question 12

Aspergilloma

Allergic broncho-pulmonary aspergillosis

Answer 12

Usually asymptomatic colonization of pre-existent cavity with slow progression…main sx is hemoptysis

Local hyper-immune rxn leading to bronchiectasis…presents as asthma

Question 13

Mucormycosis

Answer 13

Spore inhalation

Prolonged neutropenia and diabetes with ketoacidosis are risk factros along with heavy metal chelaiton therapy

Pulmonary and rhinocerebral sxs

AMphotericin B and aggrsessive surgery…only active imidazole is posaconozaole

Question 14

Actinomyces

Nocardia

Answer 14

Filamentous, gran-pos bacteria part of mouth flora…crosses tissue plans, invades chest wall and creates fistulas…sulfur granules

Also filamentous but weakly acid fast…immunocompromised and nodular without cavitation

Question 15

Serology

Answer 15

Measures immune response

Best for coccidiomycosis

Histoplasma has 50% false neg and blasto even less sensitive

Question 16

Urine antigen

Answer 16

For histo and blasto

Negative in lung limited, must be disseminated…works with better in immunocompromised

Cross reacts with both fungi

Question 17

Beta-Glucan

Answer 17

Most fungal species (except crypto ans mucor)…best for invasive fungal infections

Neg doesnt rule out

Question 18

Galactomannan

Answer 18

Aspergillus

False positive with Beta-lactams, plasmalyte and other fungal infections