Mycobacteriumaerobic, non-endospore-forming rodsmyco = fungus-like

Mycobacteriumdistinctive cell wall: waxy, water-resistant layerresistant to stress: e.g. dryingfew antimicrobial drugs can enter the cellnutrients enter slowly = slow growth rate

Mycobacterium aviumReadings 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?

MACcommon bacteriaweakened immune system: opportunisticblood infections, hepatitis, pneumoniacombination of antibiotics:azithromycin (Zithromax)clarithromycin (Biaxin)3 other drugs

Mycobacterium tuberculosisslender rod, obligate anaeroberods grow slowly and tend to grow in clumpsresistant to conventional staining

Mode of Transmissionfine particles: 1-3 bacilli reach the lungs

Readings question #2:Explain the process of M. tuberculosisattacking macrophages. When does the tubercleform? What happens when the macrophages die?Describe the process of liquefaction and its endresult. What is cavitation?

Ghon Complexesdormant disease: lesions calcify

Miliary Tuberculosiscardiovascular and lymphatic systems

defenses overwhelmed

weight loss, coughing (blood), general malaise

Treatmentstreptomycinmultiple drugschemotherapy for monthstubercle bacillus grows slowlyhidden by macrophages or other locations difficult to reach with antibiotics

DiagnosisTuberculin Skin Test: purified protein derivitiveMantoux Test: most accurate tuberculin test Induration induration

Tuberculosis VaccinesBCG: live culture of Mycobacterium bovisavirulent cultureavailable since the 1920scertain children at high riskpositive reaction to tuberculin skin testsnot effective for adolescents and adults

Spirochetesa 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.

Spirocheteshuman oral cavityAmong first organisms described by van Leewenhoek in the 1600s that he found in saliva and tooth scrapings.3 common genera: Borrelia Leptospira Treponema

Leptospira interrogansleptospirosisdomestic or wildexceedingly fine spiralobligate aerobeanimals shed bacteria in their urinehumans infected by contact with urine-contaminated water or soil, or animal tissue

Leptospirosis

Portal of Entryminor abrasionswhen ingested: mucosa of upper digestive systemincubation period of 1-2 weeksacute symptoms subsidesecond episode of fever: Weils Diseasekidney failure is the most common COD

Borrelia burgdorferitick-borne disease: seasonal occurrence lack of contagiousness unusual skin rash

bacterial pathogen: penicillin1983: spirochete identified as the causeLyme Disease most prevalent on Atlantic coast

Tick Feeding Cyclefirst and second feedings: larva and nymphthird feeding: adult

Deer Tick

Erythema Migrans75% of all cases15 cm and resembles bulls eye

Second Phaseheart: pacemakerchronic neurological symptoms: facial paralysis, meningitis, encephalitisarthritic symptomsdiagnosis: symptoms, geographic areano laboratory test for Lymes diseaseseveral antibiotics are effective

Removing a Tick

Treponema pallidumgram-negative spirochete, thin and tightly coiledStains poorlyGreek: twisted thread pale

Primary Stage of SyphilisReadings question #3: What is the most notable sign for the primary stage of syphilis?

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

Secondary Stage of Spyhilis mucous patches anal warts

Tertiary Stage of SyphilisReadings question #5: During the tertiary stage of syphilis, what distinguishing sign occurs?

lesions may ulcerate and cause extensive tissue damage

Congenital Syphilistransmitted across the placentadamage to mental development and other neurological symptomspregnancy during the primary or secondary stage is likely to produce a still birth

Treatment for Syphlisbenzathine penicillin: effective in the body for 2 weeksdoxycycline for penicillin-sensitive people

Antibiotic therapy must be administered for a longer period of time due to the slow-growing spirochete.