The Bacteria II

Question 1

Helicobacter pylori

Answer 1

G-
Spiral bacteria
P: acid resistance, cagA gene (ulcer formation)
CS: Gastric and duodenal ulcers

Question 2

Treponema pallidum

Answer 2

Non gram staining
Spirochete
Darkfield microscopy or labeled antibodies
P: Lack of proteins in cell wall, antigenic variation
CS: Primary syphilis (painless chancre), Secondary syphilis (fever, myalgia, headache, rash), Tertiary syphilis (neurosyphilis or cardiovascular syphilis), Congenital syphilis (facial and tooth abnormalities)

Question 3

Mycobacterium tuberculosis

Answer 3

-Acid-fast bacilli
-Ziehl-Neelson staining required
P: replication in alveolar macrophages, dissemination to other tissues
CS: Pulmonary disease, reactivation dx, disseminated dx to kidneys, bones

Question 4

Mycobacterium avium complex

Answer 4

Acid-fast bacilli
Special Ziehl Neelson staining
Slow growing, fastidious requirements
P: Inhibition of phagosome-lysosome fusion
CS: Pulmonary disease, disseminated dx in AIDS or immunocompromised pt’s

Question 5

Genital mycoplasma

Answer 5

eg. M. hominis, M. genitalium
Non gram staining
No cell wall
Needs special growth requirements
P: Resistant to beta lactams
CS: Non-gonococcal urethritis in males

Question 6

Mycoplasma pneumoniae

Answer 6

Non gram staining
No cell wall
Requires special growth media
P: Polyclonal B and T cell activators, triggers formation of cold agglutinins
CS: Atypical pneumonia, dermatological involvement, cardiac and neurological complications

Question 7

Chlamydia trachomatis

Answer 7

Obligate intracellular bacteria
Non-cultivable
P: inhibits phagosome-lysosome fusion
CS: urethritis, epidydimitis, proctitis, PID, cervicitis

Question 8

Chlamydophila psittaci

Answer 8

Obligate intracellular bacteria
Non-cultivable
P: vertebrate vector (birds)
CS: Atypical pneumonia

Question 9

Rickettsia rickettsii

Answer 9

Obligate intracellular bacteria
Small, gram negative
P: Dermatocantor spp. vector (ticks), cell to cell spread (hundreds of contiguously infected epithelial cells)
CS: Rocky Mountain Spotted Fever