bacterial inf with animal reservoirs/insect vectors

Question 0

brucellosis

Answer 0

-ppl handling animals, INHALED/INGESTION
-unpasteurized milk and cheese
-causes acute sys dz or chronic infection with periodic febrile episodes from bacteria x in macrophages –> granulomas, liver abscesses
SX: undulant fever, most common complication: bones, joints (spondylitis of lumbar spine), suppurative in large joints, DEATH caused by ENDOCARDITIS
TX: tetracycline, aminoglycosides, rifampin ab

Question 1

8 bacterial inf w. animal reservoirs or insect vectors

Answer 1

1. brucellosis
2. plague
3. tularemia
4. anthrax
5. listeriosis
6. cat-scratch dz (bartonella henselae)
7. glanders
8. bartonellosis (bartonella bacilliformis)

Question 2

plague - the Black Death
high mortality untx
recc. tetracycline w. streptomycin

Answer 2

-caused by yersinia pestis (rats–>fleas–>humans (PNA –>spread inf via resp))
-bacteria x in macrophages –> LN –> necrosis (buboes in LN), if it gets into blood –> lungs (necrotizing pneumonitis)
3clinical stages:
1. bubonic: headache, fever, painful LN
2. septicemic: when bacteria in blood directly
3. pneumonic: sudden cough + SOB -> resp insuff, endotoxic shock

Question 3

tularemia

Answer 3

-caused by francisella tularensis thats present in TICKS, RABBITS. gets into blood/direct contact/inhaled/ingested
-inoculation site–>EXUDATIVE PYOGENIC ULCER
-if gets into LN–> macrophages (when activated can kill it) systemically (heart, kidneys, lungs (resembles primary TB))
4 clinical presentation:
1. ulceroglandular tularenia (generalized tularenia)
2. oculoglandular tularenia (BLINDNESS)
3. typhoidal tularenia (fever, hepatosplenomegaly, toxemia)
4. pneumonic tularemia

Question 4

anthrax

Answer 4

-caused by bacillus anthracis (spore forming) in animal byproducts: wool, hides, brushes, bone meal) and enters humans by:
skin (localized-ok): malignant pustule, bloody purulent exudate, ulcerate –>black scab
inhalation+ingestions, pul inf(necrotizing hemorrhagic PNA) : septicemic anthrax: wide tissue destruction FATAL

Question 5

listeriosis (prolonged Ab, mortality at 25%)

Answer 5

• listeria monocytogenes that grows in 4c, in unpasteurized dairy
• spreads from cell to cell
• pregnancy: infant mortality high even with ab
• adults: MENINGOENCEPHALITIS and SEPTICEMIA (severe febrile dz in IC pts) –> shock, DIC (misdx as gram-sepsis)
  risks: ROH, cancer, AIDs

Question 6

cat scratch dz

Answer 6

• bartonella henselae from cats (kids get it more often) causes self-limited GRANULOMATOUS and suppurative LYMPHADENITIS (tender and enlargement)
• parinaud oculoglandular sd: periauricular adenopathy secondary to conjunctival inf. AB DONT HELP

Question 7

glanders

Answer 7

-pseudominas mallei from horses. humans get it from inhalation and contact.
ACUTE GLANDERS: bacteremia, severe prostration (lying flat on ground), fever, granulomatous abscesses –> FATAL
chronic glanders: low grade fever, draining abscesses from skin, lymphenopathy, hepatosplenomegal, granulomas MIMIC TB. mortality >50%

Question 8

bartonellosis - acute anemia and chronic skin dz

Answer 8

-caused by bartonella bacilliformis that’s transmitted by sandflies.
-causes biphasic pattern: acute hemolytic anemia first –> oroya fever (fever and skeletal pains)
months later, chronic dermal phase–> verruga peruana (lesions on extensor surfaces, low mortality)