1. aerobic, non-endospore-forming rods myco = “fungus-like”
Mycobacterium
aerobic, non-endospore-forming rods
myco = “fungus-like”

2. Mycobacterium distinctive cell wall: waxy, water-resistant layer
resistant to stress: e.g. drying
few antimicrobial drugs can enter the cell
nutrients enter slowly = slow growth rate

3. Mycobacterium avium Readings question #1: What is MAC?
Who is susceptible to this infection?
What are the common symptoms?
What organism is responsible?
Where is it found?
What are its portals of entry?

4. MAC common bacteria weakened immune system: “opportunistic”
blood infections, hepatitis, pneumonia
combination of antibiotics:
azithromycin (Zithromax)
clarithromycin (Biaxin)
3 other drugs

5. Mycobacterium tuberculosis
slender rod, obligate anaerobe
rods grow slowly and tend to grow in clumps
resistant to conventional staining

6. Mode of Transmission fine particles: 1-3 bacilli reach the lungs
Readings question #2:
Explain the process of M. tuberculosis
attacking macrophages. When does the tubercle
form? What happens when the macrophages die?
Describe the process of liquefaction and its end
result. What is cavitation?

7. Ghon Complexes
dormant disease: lesions calcify

8. Miliary Tuberculosis cardiovascular and lymphatic systems
defenses overwhelmed
weight loss, coughing (blood), general malaise

9. Treatment streptomycin multiple drugs chemotherapy for months
tubercle bacillus grows slowly
hidden by macrophages or other locations difficult to reach with antibiotics

10. Diagnosis Tuberculin Skin Test: purified protein derivitive
Mantoux Test: most accurate tuberculin test
Induration induration

11. Tuberculosis Vaccines
BCG: live culture of Mycobacterium bovis
avirulent culture
available since the 1920’s
certain children at high risk
positive reaction to tuberculin skin tests
not effective for adolescents and adults

12. Spirochetes
“a genus of bacteria having a flexible cell wall but no flagella in the traditional sense. Movement occurs by contractions (undulating) of long filaments (endoflagella) that run the length of the cell.”

13. Spirochetes human oral cavity
Among first organisms described by van Leewenhoek in the 1600’s that he found in saliva and tooth scrapings.
3 common genera: Borrelia
Leptospira
Treponema

14. Leptospira interrogans
leptospirosis
domestic or wild
exceedingly fine spiral
obligate aerobe
animals shed bacteria in their urine
humans infected by contact with urine-contaminated water or soil, or animal tissue

15. Leptospirosis

16. Portal of Entry minor abrasions
when ingested: mucosa of upper digestive system
incubation period of 1-2 weeks
acute symptoms subside
second episode of fever: Weil’s Disease
kidney failure is the most common COD

17. Borrelia burgdorferi tick-borne disease: seasonal occurrence
lack of contagiousness
unusual skin rash
bacterial pathogen: penicillin
1983: spirochete identified as the cause
Lyme Disease most prevalent on Atlantic coast

18. Tick Feeding Cycle first and second feedings: larva and nymph
third feeding: adult

19. Deer Tick

20. Erythema Migrans
75% of all cases
15 cm and resembles “bull’s eye”

21. Second Phase heart: pacemaker
chronic neurological symptoms: facial paralysis, meningitis, encephalitis
arthritic symptoms
diagnosis: symptoms, geographic area
no laboratory test for Lyme’s disease
several antibiotics are effective

22. Removing a Tick

23. Treponema pallidum gram-negative spirochete, thin and tightly coiled
Stains poorly
Greek: “twisted thread” “pale”

24. Primary Stage of Syphilis
Readings question #3: What is the most notable sign for the primary stage of syphilis?

25. Secondary Stage of Syphilis
Readings question #4: List 3 signs and symptoms that an individual may experience during the secondary stage of syphilis.

26. Secondary Stage of Spyhilis
mucous patches anal warts

27. Tertiary Stage of Syphilis
Readings question #5: During the tertiary stage of syphilis, what distinguishing sign occurs?
lesions may ulcerate and cause extensive tissue damage

28. Congenital Syphilis transmitted across the placenta
damage to mental development and other neurological symptoms
pregnancy during the primary or secondary stage is likely to produce a still birth