Microbiology Flashcards
Type of mechanism of action
Diphtheria toxin, Exotoxin A, and Shiga toxin
Inhibit protein synthesis
Diphtheria toxin and pseudomonas aeruginosa method of action
Ribosylation of EF-2 –> decreased protein synthesis
Shigella toxin inhibits protein synthesis by what mechanism
Inactivation of 60S ribosome unit
Clostridum perfringens causes gas gangrene though what mechanism
Phospholipase C mimetic –> splits host phospholipids –> tissue necrosis
Method of action of C. Diff
Actin depolymerization
Psudomembrane formation
Shiga toxin (from Shigella spp and Enterohemorrhagic E. Coli is associated with which disease?
Hemolytic uremic syndrome.
These 2 spirochetes are too small to see on gram staining
Treponema (syphillis) and Leptospira (infected animal urine in water)
BLT
What are the 3 types of spirochetes?
Spirochetes are spiral shaped bacteria which include
1. Borellia
2. Leptospira
3. Treponema
What kind of stain is used for Mycobacteria? Why?
Ziehl-Neelsen
Cell wall is too fatty
Really Chilly and Cold
Name the 3 intracellular anaerobes
- Rickettsia
- Chlamydia
- Coxiella
HeLiCOPters Are Silver
What bacteria/fungi are seen on silver stain?
- H. Pylori
- Legionella
- Coccidiodes
- Pneumocytis jirovecii
- Aspergillus fumigatus
Certain Bugs Really Try my Patience
What bacteria are seen on Giemsa Stain?
Chlamydia
Borellia
Rickettsia
Trypanosomes
Plasmodium
Please SHiNE my SKiS
Which bacteria are encapsulated?
Pseudomonas aeruginosa
Streptococcus pneumoniae
H. Influenzae B
Neisseria meningitis
E. Coli
Salmonella
Klebsiella
Strep agalactiae (Group B)
What are the 4 systemic fungi?
Histoplasma
Blastomyces
Coccidioises
Paracoccidioises
Demographic location
Histoplasma
Blastomyces
Coccidioises
Paracoccidioises
Histoplasma - Mississipi and Ohio Rivers
Blastomyces - Great lakes, Ohio Valley
Coccidioises - California, southwest
Paracoccidioises - South America
Histoplasma spores are typically contracted in which demographic region and from what animal droppings?
Bat and bird droppings in the Mississippi to Ohio rivers
Blastomyces yeast look like what on histology staining?
Broad Based Budding
Size of these fungi in comparison to RBCs
1. Histoplasma
2. Blastomyces dermatitidis
3. Coccioides and paracoccioides
Histoplasma - much smaller
Blastomyces - about the same
Coccioides and paracoccioides - much larger
What are the unique symptoms of Histoplasma capsulatum infection?
Mouth ulcers
Erythema nodosum
What are the unique symptoms of Blastomyces dermatitidis infection?
Skin lesion (veruccas)
Osteolytic bone lesions
Hazy chest x-ray
What are the unique symptoms of Coccidioises immitus infection?
arthralgias, erythema nodosum, meningitis
Coccidioises immitus spores are typically contracted in what demographic region and through what resovoir?
California/southwest america
The spores are found in dust, especially after an earthquake
Paracoccioides brasiliensis yeast is compared to what shape on histology?
A Captain’s Wheel
What are the unique symptoms of Paracoccioides brasiliensis infection?
Mouth ulcers
Verucca skin lesions (like blastomyces)
Cervical lymphadenopathy
What is the treatment for localized fungal infections?
-Azole drugs
What is the treatment for disseminated systemic fungal infections?
Amphotericin B
Which fungus is responsible for tinea (Pityriasis) versicolor?
Malassezia furfur
What is the method of action of malassezia versiolor for causing hyper and hypopigmentation on the chest and back?
Lipid degredation forms acid which damages melanocytes
Italian
What does malassezia furfur look like on KOH prep?
Sphagetti and meatballs
Where does malassezia furfur usually colonize?
It is part of the normal skin microbiota.
It overgrows in the humidity
Dermatophytes (fungi) cause what group of skin conditions?
Tinia
Tinia cruris is also known as?
Jock itch
What is the treatment for tinea infections?
Topical azoles
Turban
What is the treatment for onychomyocosis (nails)
Terbinafine
Tin man
What is the treatment for resistant tinea infections?
Griseofulvin
What does dermatophytes look like on KOH prep?
Branching septate hyphae
Shanked by a rose
Sporothrix schenkii is shaped like what in the human body?
A cigar
Sporothrix schenckii initially enters the body after being pricked by a thorn. How does it travel once inside?
Ascending via lymhatics
What is the treatment of rsporothrix schenckii?
Azole medications
Potassium iodide used to be used in the past
Sporothrix schenkii is also known as what disease?
Rose gardner’s disease
What is the function of protein A? Which bacteria uses it?
Bind Fc region of the antibody, preventing opsonization. Staph Aureus
SHiN
Which bacteria uses IgA protease?
What is the function?
S. pneumoniae
H. influenzae
Neisseria
Cleaves IgA, able to colonize mucous membranes
Which bacteria uses Protein M?
What is the function?
Protein M prevents phagocytosis.
Group A Strep (streptococcus pyrogenes)
Which bacteria causes toxic shock syndrome and scalded skin syndrome
Staph Aureus
Which bacteria causes toxic shock Like Syndrome and scarlet fever?
Strep pyogenes
NO StRES
What is the novibiocin sensitivity of:
Staph epidermidis
Staph saprophyticus
Saprophyticus - Resistant
Epidermidis - Sensitive
NNot
Side effects of aminoglycosides
Neprhotoxicity
Neuromuscular blockade
Ototoxicity
Teratogenicity
GNATS
What drugs belong to aminoglycosides
Gentamycin
Neomycin
Amikacin
Tobramycin
Streptomycin
Symptoms of Lyme Disease
- Flu like symptoms, target rash
- Months later - facial palsy
- Asymmetric arthritis (knee)
Treatment of Lyme disease
Doxycycline, ceftriaxone
