to dx

Question 1

grp A beta hemolytic strep (strep pyrogens)

Answer 1

• ASO titer to see if high circulating levels of streptolysin O enz
• swab with a rapid ag detection test (RADT) and/or culture to confirm if have strep pharyngitis from this bac

Question 2

neonatal meningits from grp B beta hemolytic strep (strep algalatiae)

Answer 2

lubbar puncture

Question 3

strep pnemoniae

Answer 3

quelling rxn: when pneumococci mixed with anti-serum (serum w abs to capsule) and methylene blue => capsule will swell

Question 4

nisseria gonorrhea

Answer 4

diplococci donute in WBCs

Question 5

moraxella catarrhalis

Answer 5

otitis media in kids

Question 6

salmonella typhi

Answer 6

culture bood, urine, stool

Question 7

mycobacterium TB

Answer 7

+ PPD test:
• >5mm in persons that have HIV or are immunosuppressed.
• >10mm in persons with common risk factors for exposure to TB like being from somewhere that is endemic, working in healthcare, prior incarceration, having diabetes or renal failure.
• >15mm for all others.

CXR: isolated granuloma, ghon focus/complex, old scarring in an upper lobe, or active TB pneumonia.

Sputum acid-fast stain and culture: indicates an active infection when +.

Rapid molecular detection of MTB: used on the sputum, uses PCR, gold standard, but expensive.

Question 8

mycobacterium leprae

Answer 8

Lepromin skin test
• Similar to the PPD for TB.
• Measure ability of host to mount a t4HST against M leprae
• TL ppl wld be + and LL ppl wld be -
• Used mostly to place the pt on the spectrum than to diagnose.

Question 9

treponema pallidum

Answer 9

Nonspecific treponemal test

then a specific treponemal test

Question 10

lyme dis from borrelia burgdorferi

Answer 10

• If there is ECM, the leading edge of the rash can be biopsied.
• This bug is difficult to culture, so testing for abs is typically better with ELISA and western blot

Question 11

relapsing fever from borrelia recurrentis

Answer 11

• Only culture during the febrile periods.
• Look for the spirochete between RBCs.
• Darkfield is also helpful.

Question 12

inclusion conjunctivitis of chalmydia trachomatis

Answer 12

intracytoplasmic inclusion bodies in cells that came from the palprebral conjunctival surface.

Question 13

mycoplasma pnemoniae

Answer 13

• cold agglutinins
• compliment fixation
• sputum culture
• PCF