Opportunistic resp infections Flashcards
Negative stain for Cryptococcus
India ink/Nigrosin
Obligate EC fungal pathogen of humans that cannot be grown in the lab
Pneumocystis jirovecii
Fungus with cholesterol cytoplasmic membrane instead of ergosterol
Pneumocystis jirovecii
Appears as silver-stained cysts in BAL. Unable to be cultured
Pneumocystis jirovecii
Fungal pathogen that kills type I pneumocytes, causing an excess replication of type II
Pneumocystis jirovecii
Cause of fluid, foamy, honeycomb appearance of alveoli in Pneumocystis pneumonia
Alveoli are filled with desquamated alveolar cells, monocytes, and organisms
CD4 count at a higher risk for Pneumocystis pneumonia
<200
Prophylaxis options for Pneumocystis pneumonia
Trimethoprim-Sulfamethoxazole
Dapsone with/without pyrimethamine
Atovaquone
Pyrimethamine
Treatment for Pneumocystis pneumonia
Trimethoprim-Sulfamethoxazole
Infectious form of aspergillosis
Conidia/spores
Invasive filamentous hyphae invade lung tissues and blood vessels
Aspergillosis
Risk factors for aspergillosis
Neutropenia
CGD
TNF-alpha inhibitor
Steroid
Immunosuppressant
Transplant
Microscopy of lung biopsy shows 45 degree/acute angle branching and septate hyphae
Aspergillosis
Risk factors for allergic bronchopulmonary aspergillosis
CF
Asthma
Eosinophilia
Elevated IgE
Colonization of preformed pulmonary cavities and paranasal cavities with fungal balls, with recurrent hemoptysis
Aspergilloma
Risk factors for dissemination of invasive pulmonary aspergillosis
Hematological malignancies
Immunosuppressive drugs
Solid organ transplant
Neutropenia
Risk factors of zygomycoses
DKA
Hematological malignancies
Neutropenia
Microscopy of exudate shows broad, ribbon-like, non-septate hyphae with broad (90 degree) angle branching
Zygomycoses
Treatment of Zygomycoses
Rapid debridement
Amphotericin B
Control DM
Angioinvasive fungi
Zygomycoses
Aspergillus
Non-septate filamentous fungi
Zygomycoses - rhizopus
Mucormycosis - mucor
Phycomycosis - absidia
Bacterial zoonotic pneumonia causal organisms
Chlamydia psittaci
Coxiella burnetti
Bacillus anthracis
Tularemia
Transmission of psittacosis
From infected birds
Causal organism in Q fever
Coxiella burnetti
Gram positive box-car shaped in tissue. Central spore bearing in environment
Bacillus anthracis
Rough ground glass colonies on blood agar with sticky consistency. Medusa head appearance.
Bacillus anthracis
Specific stain for Bacillus anthracis
McFadyean
Mechanism of edema factor of Bacillus anthracis
Calmodulin dependent activation of adenylyl cyclase to cause efflux of fluid
Mechanism of LF-MAP kinase of Bacillus anthracis
Protease that increases secretion of TNF leading to cell death
Treatment for anthrax
Ciprofloxacin for 30 days
Preventative for anthrax
Acellular vaccine adsorbed/Raxibacumab
Causes of fungal pneumonia from animals
Histoplasma capsulatum
Cryptococcus neoformans
Negative sense, enveloped, ssRNA with 3 segments. Transmitted through rodent excreta.
Hantavirus/Bunyavirus
Complications of Hantavirus
ARDS
Renal failure
Hemorrhage
High mortality rate
Virus with multisystem pathology characterized by damage to capillaries and small vessel walls that results in vasodilation and congestion with hemorrhages leading to HTN, oliguria, and shock
Hantavirus
Subtype of hantavirus that causes severe/classical HVD
Hantaan
Subtype of hantavirus causing moderate HVD
Seoul
Hantavirus subtype causing mild HVD
Puumala
Hantavirus subtype that causes hantavirus pulmonary syndrome
Sin Nombra
5 phases of Hantavirus
Febrile
Hypotensive
Oliguric
Diuretic - recovery
Convalescent
Motile, strict aerobe, oxidase positive, gram negative bacilli
Pseudomonas aeruginosa
Mechanism of exotoxin A of Pseudomonas aeruginosa
Inhibits protein synthesis by ADP ribosylation of EF-2
Mechanism of Exotoxin S of Pseudomonas aeruginosa
Induces apoptosis by acting on regulatory G proteins
Mechanism of Pyocyanin of Pseudomonas aeruginosa
Stimulates IL-8
Lung colonization in early childhood pts with CF
H influenzae
S aureus
Lung colonization young adults with CF
Pseudomonas aeruginosa
Burkholderia cepacia
Aspergillus fumigatus