Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Z - Micro 07
Micro 07
| Question | Answer |
|---|---|
| Ixodes tick - arthropod! | Lyme disease, Borrelia burgdorferi, spirochete, motile via axial filaments. |
| How to prevent Lyme disease? | regular tick checks because it takes greater than 24 hrs of the tick attachment for transfer of the organism |
| White-footed mouse, white-tailed deer, Northern U.S. | Lyme disease, Borrelia burgdorferi |
| erythema chronicum migrans | Lyme disease, Borrelia burgdorferi. Painless skin lesion at site of tick bite. Target lesion. |
| high fevers and photophobia | Leptospira, leptospiremic phase |
| Where is Leptospira found? | urine of animals (dogs, rats, livestock, etc), swimming in contaminated water |
| swimming in bad water, renal failure, jaundice, mental status changes | Leptospira, Weil's disease, organisms can be found in patient's urine in the second phase of the illness. |
| What kind of necrosis does M. TB cause in the lungs? | Caseous necrosis, surrounded by macrophages, multinucleated giant cells, fibroblasts, etc ==>calcifies. M.TB stays alive in these granulomas. |
| What part of the lungs are affected by M TB? | middle and lower lung zones - the parts with the highest airflow |
| Ghon focus | TB: calcified tubercle in middle or lower lung zones. Tubercles: granulomas that house the M. TB bug. |
| What is the most common site of reactivation TB? | Lungs - apical areas around the clavicles |
| Patient with productive cough with blood in it -- hx of exposure to HIV patients | M. TB - reactivation TB |
| Scrofula | TB in the lymph nodes -- most common manifestation of TB outside the lungs |
| Sterile pyuria | TB in the kidney, but only see WBC's and RBC's in the urine -- no organisms |
| Pott's disease | TB in the thoracic and lumbar spine -- destroy the intervertebral discs and adjacent vertebral bodies |
| Chronic arthritis of 1 joint | TB |
| Chronic arthritis of 1or 2 of the large peripheral joints (knee) - more than 1 year | Late stage lyme disease (Borrelia burgdorferi) |
| In a patient suspected of TB, if the acid-fast stain or culture FROM THE SPUTUM is positive, what does it tell you about the disease? | Active pulmonary infection |
| Infection with Mycobacterium avium-intracellulare (MAI) or MAC | AIDS pts, harbinger of death because it only strikes hen the T-helper count is virtually nonexistent |
| Where does Mycobacterium leprae like to grow? | Cooler areas of the body, close to the skin surface |
| Which is more severe? Lepromatous leprosy or Tuberculoid leprosy? | Lepromatous (leonine facies, saddlenose deformily, negative lepromin skin test because can't mount cell-mediated immune response) |
| What is special about mycoplasma? | tiniest free-living organisms capable of self-replication; no peptidoglycan wall, cell membrane packed with sterols |
| Name the two mycoplasma organisms we're interested in | Mycoplasma pneumoniae and Ureaplasma urealyticum |
| What is the number one cause of bacterial bronchitis and pneumonia in teenagers and young adults? | Mycoplasma pneumoniae |
| cold agglutinins | RBC antigens similar to antigens of Mycoplasma pneumoniae. Abs against Mycoplasma pneumoniae attach to RBC's at 4 degrees Celcius |
| Complement fixation test | antigens from Mycoplasma pneumoniae. Mix patient's serum with the antigens. 4x rise in antibody titer between acute and convalescent samples is diagnotic of a recent infection. |
| How to ID Ureaplasma urealyticum? | metabolizes urea into ammonia and CO2 |
| What must your media have if you want to grow mycoplasma? | cholesterol and nucleic acids/urea |
| What do aminoglycosides cover? | G-, AEROBIC, enterics, Pseudomonas (Mean negative Guy with boxing gloves, does aerobics to stay in shape, jump around a lot so jostles stuff in the intestines and has blue/green sheen uniform) |
| Name drugs that are aminoglycosides | Mean GNATS canNOT kill anaerobes (because it requires O2 for uptake into the cell). Gentamicin, Neomycin, Amikacin, Tobramycin, Streptomycin. NOT: Nephrotoxic (with cephalosporins), Ototoxic (with loop diurectics), Teratogenic |
| What is neomycin used for? | bowel surgery |
| Name two common aminoglycosides | Streptomycin (oldest one, many bugs resistant to it), Gentamicin (given in conjunction with penicillins to give it access through the outer membranes) |
| What is the mechanism of aminoglycosides? | 1. Stops the initiation complex in translation, 2. misreads the code, 3. polysome --> monosome. A 30-yo boxer (30S ribosomal unit) so he's really cheesy and stupid: STOP in the name of love (stops the initiation complex) & he can't read very well (misrea |
| What is the mechanism of resistance to aminoglycosides? | bacterial transferases modify the AG's |
| Adverse effects of AG's | 1. Mean guy -- 8th round boxing: 8th nerve toxicity - causes vertigo and hearing loss (irreversible) in his opponent!, 2. Left hook to kidney - renal toxicity (reversible), 3. KO - complete neuromuscular blockade |
| Spectinomycin | Sounds like AG, hits the 30S and is given IV, but not in the AG group! |
| What do you use spectinomycin for? | N gonorrhea that is resistant to both penicillin and tetracyclin |
| Name the anti-TB drugs | INH-SPIRE. INH used alone for TB prophylaxis. Streptomycin Pyrazinamide INH Rifampin Ethambutol used in combo for TB Treatment. All are hepatotoxic |
| What is the mechanism of Isoniazid in treating TB? | INH - interferes with biosynthesis of mycolic acid in cell wall of Mycobacteria |
| Why shouldn't you drink alcohol while on INH? | Alcohol induces CYP450 system --> increases metabolism of INH --> inc risk of developing hepatitis AND decreases INH therapeutic effect |
| Why should you prescribe Vit B6 with INH? | INH increases urinary excretion of B6 (needed for proper nerve function) --> decreased B6 in body --> pellagra (neurotoxicity) |
| Rifampin | 4 R's of Rifampin: RNA polymerase inhibitor, revs up CYP450, red/orange body fluids, rapid resistance if used alone |
| What drug turns your body fluids red? | Rifampin (anti-TB) |
| What is the mechanism of rifampin? | inhibits DNA-dependent RNA polymerase of M TB |
| What does Rifampin do to the CYP450 system? | Induces it --> increases metabolism of other drugs such as warfarin/coumadin, OCPs, anticonvulsants (can lead to seizures) |
| What drug used for MAI/MAC? | Rifabutin (like rifampin) |
| What is ethambutol and why is it not used in children? | anti-TB drug, causes loss of central and color vision. Not used in children because they can't report visual deterioration. |
| Deaf neonate, mom with hx of N gonorrhea infection | Used streptomycin while pregnant (causes ototoxicity and nephrotoxicity) |
| What is the first line drug for leprosy? | Dapsone |
| What is clofazimine? | Anti-leprosy drug. Clown climbs DNA -- binds to the DNA of Mycobacterium Leprae. |
| What is a side effect of clofazimine? | Turns skin and conjunctiva red (because it's a red-colored compound) |
| Leprosy drug reactions | Type 1: borderline pts, delayed hypersensitivity (type 4), Type 2: borderline lepromatous and lepromatous, immune complex mediated reaction (type 3) |
| What is the only use of thalidomide that is condoned in the U.S.? | To treat Type 2 reaction from taking leprosy drugs (because thalidomide is a teratogen) |
| What are flouroquinolones? | "-floxacin" (flocks of sinners), inhibit DNA gyrase (topoisomerase II) --> break bacterial DNA --> bactericidal |
| What is the mechanism of bacterial resistance to flouroquinolones? | point mutation in bacterial GNA gyrase --> flouroquinolones can't inhibit the enzyme anymore |
| How is ciprofloxacin different from 3rd and 4th generation flouroquinolones? | inhibits GABA --> can cause seizures |
| What do flouroquinolones cover? | G- (of urinary and GI tracts) including P aeruginosa and enterics (E coli, Salmonella, Shigella, Campylobacter) |
| Adverse effects of flouroquinolones | GI irritability (flox of sinners party so much you throw up), damage cartilage (flox of sinners like to eat chicken wings -- cartilage), Tendonitis/rupture (FlouroquinoLONES hurt attachment to your BONES. |
| Levofloxacin | Flouroquinolone with G- coverage PLUS improved G+ coverage -- good for community acquired pneumonia |
| What does vancomycin cover? | All G+, even MRSA! |
| Red man syndrome | IV administration of vancomycin too fast --> release of histamine --> rash of the torso and itching skin |
| What is the mechanism of vancomycin? | inhibits biosynthesis of G+ peptidoglycan production: complexes with D-ala D ala to inhibit transpeptidation |
| Vancomycin | Comes down IV tube (given IV) in Red Cross van (G+) --> going NOT so fast (nephrotoxicity, ototoxicity, thrombophlebitis) --> driven by a Red Man Indian --> wheels latch on to d-ala-d-ala and that brings it in to destroy the peptidoglycan wall |
| Mechanism of Trimethoprim and Sulfamethoxazole | Bacteria --(PABA)--> TH4 (humans don't make this; we get it as a vitamin) --> purines + dihydrofolate --(dihydrofolate reductase)--> TH4. Sulfameth looks like PABA and inhibits there, while Trim looks like DHFR. Block folate synthesis --> can't make hem |
| What does Sulfamethoxazole cover? | NO anaerobics, but G- and G+, Nocardia, Chlamydia, simple UTI. |
| What do Trimethoprim and Sulfamethoxazole cover? | recurrent UTI's, PCP, Shigella, Salmonella. TMP/SMX UPSS |
| Adverse effect of sulfamethoxazole | SULTAN can't pee (tobulointerstitial nephritis), has yellow eyes (kernicterus), and hold albumin in his hands (displace other drugs from albumin -- like warfarin) |
| Adverse effect of trimethoprim | TMP Treats Marrow Poorly: megaloblastic anemia, leukopenia, granulocytopenia (may alleviate with supplemental folinic acid) |
Created by:
christinapham
Popular USMLE sets