MSK- MICRO – Flashcards
Unlock all answers in this set
Unlock answersquestion
| Can you name 6 ways that bacteria establish resistance to antibiotics? |
answer
| Inhibit uptake, inactivate drug, efflux pump, alter target site, overproduce target site, alter metabolism |
question
| How do bacteria avoid the action of Beta Lactams? |
answer
| 1- Alteration of target sites- as in PRSP- penicillin resistant strep pneumo 2- Alter the drugs access to the target 3- Inactivate the drug |
question
| Why do bacteria sometimes overproduce PBP? |
answer
| To soak up the drug- there is still enough target site left to do its job |
question
| How is resistance established by changing the nature of the PBP? |
answer
| Picking up a new form of PBP The new form has a much lower affinity PBP (drug binding site) |
question
| A catalase +, coag +, gram + cocci is most likely? |
answer
| Staph Aureus |
question
| How do we treat MRSA? |
answer
| Vanco |
question
| How do we treat MSSA? |
answer
| Nafcillin and Oxacillin |
question
| What type of bacteria have the ability to restrict access to PBP? Why? |
answer
| Gram NEGATIVE RODS- They have an outer membrane that gram + don't have that includes porin proteins that can be made smaller to keep out Beta Lactams |
question
| What type of bacteria have porins, why are they special, and what is the role of porins in resistance? |
answer
| Gram - Rods They allow nutrients and drugs into the cell The cell can make the porins smaller to keep Beta Lactams out |
question
| What enzyme inactivates Beta Lactams? |
answer
| Beta Lactamase (there are different kinds) |
question
| How do we overcome Beta Lactamases? |
answer
| Use CLAVALONIC ACID, which inhibits Beta Lactamases and allows the Beta Lactam to do its job |
question
| What are 2 outcomes for resistance in gram + bugs? |
answer
| Bacteria which drug fails to bind to Bacteria which acquire Beta Lactamase |
question
| What are 3 outcomes for resistance in gram - bugs? |
answer
| Altered PBP Enzymes to inactivate EXCLUDING DRUG BY SHRINKING PORINS |
question
| What gene codes for resistance in MRSA? |
answer
| MEC A- makes a different, lower affinity PBP |
question
| How does Vanco work? |
answer
| It doesn't work on PBP but it DOES inhibit cell wall synthesis -binds to the D-Ala to prevent cross-linking |
question
| How does VAN A work in resistance to Vanco? |
answer
| Makes a different NAM using D-Ala AND D-Lactate- Vanco cannot bind to this |
question
| What two strains are resistant to Vanco? |
answer
| VRE- Vanco Resistant Enterococci VRSA- Vanco Resistant Staph Aureus |
question
| What are 3 sources of infection in osteomyelitis? |
answer
| Hematogenous, contiguous, and Trauma/Frax/Surgery |
question
| What bug is the primary cause of hematogenous osteomyelitis? |
answer
| Staph Aureus |
question
| What are you likely to find in a contiguous osteomyelitis infection? |
answer
| Gram+ cocci, Gram- rods, anaerobes MIXED INFECTION |
question
| What bug is likely to cause osteomyelitis from fracture, trauma, or surgery? |
answer
| Staph Aureus |
question
| What are two signs on blood tests that suggest infection/osteomyelitis? |
answer
| CBC- Increased WBCs ESR- Increased Sed Rate |
question
| What are 4 options for treatment of osteomyelitis? |
answer
| Drainage, Debridement, Surgery, Long Term Antibiotics MUST TREAT THE SOURCE!!! |
question
| What bug is the MOST COMMON cause of osteomyelitis? |
answer
| Staph Aureus- gram+ cocci, Grape-like cluster, CATALASE+, COAG+ |
question
| What bug is the major cause of nosocomial infections, device related infections, and postsurgical complication? |
answer
| STAPH AUREUS |
question
| What bug is Gram+ cocci found in CHAINS and CATALASE NEGATIVE? |
answer
| Strep |
question
| What bug contributes greatly to/makes biofilm, and what encases the biofilm? |
answer
| Staph Aureus; exopolysaccharide matrix |
question
| What do we have to do to treat biofilm? |
answer
| PHYSICALLY REMOVE- the sugars in exopolysaccharide make a sticky gel-like substance that drugs and the immune system cannot penetrate |
question
| What bug is responsible for osteomyelits and osteochondritis, is highly resistant to antibiotics, makes a biofilm, and is found most often in puncture wounds? |
answer
| Pseudomonas Aeruginosa |
question
| What bug produces GREEN pigment in wound drainage, has a grapelike odor, and grows on MACCONKEY AGAR? |
answer
| Pseudomonas Aeruginosa |
question
| Name this bug: Alginate capsule Gram Negative Rod Lactose Negative Associated with IV drug use? |
answer
| Pseudomonas Aeruginosa |
question
| Pott disease is caused by: |
answer
| Myco Tuberculosis |
question
| What is miliary TB? |
answer
| Disseminated- spread to spine- osteomyelitis |
question
| What bug is acid fast, causes osteomyelitis, and disseminates to the spine? |
answer
| TB |
question
| Childeren with sickle cell are most likely to get osteomyelitis from what bug? |
answer
| Salmonella |
question
| What is the triad of symptoms in reactive arthritis? |
answer
| Joint inflammation (polyarticular, KNEE) Conjunctivitis Urethritis/Cervicitis |
question
| A patient had diarrhea 023 days ago. They present to you complaining of painful joints and burning while urinating. You immediately suspect: |
answer
| Reactive arthritis (the artist formerly known as "Reiter's Syndrome") |
question
| When does reactive arthritis usually present? |
answer
| 2-4 weeks after primary infection |
question
| What are some primary infections that can cause reactive arthritis later on? |
answer
| GI: Campy, Salmonella, Shigella, Yersinia STD: Chlamydia |
question
| What marker is associated with reactive arthritis? What population usually gets reactive arthritis? |
answer
| HLA-B27; White males 20-40 years old |
question
| How is reactive arthritis diagnosed? What DOESN'T work? |
answer
| Genital swab for chlamydia; patient history You will NOT find bugs in the synovial fluid because the problem is autoimmune |
question
| A patient presents to you with a very swollen, seemingly arthritic knee. You aspirate synovial fluid and it is CLOUDY- what does this mean? |
answer
| Septic Arthritis- gonococcal OR nongonoccocal |
question
| What joints are most often affected by septic arthritis? |
answer
| KNEE, HIP, ankle, shoulder, elbow, wrist |
question
| What are some important risk factors for septic arthritis? |
answer
| History of arthritis (joint already damaged), PROSTHESIS, gonorrhea, trauma, immunosuppression, IV drug users |
question
| In septic arthritis, what do we see on blood studies? |
answer
| CBC: increased NEUTROPHILS ESR and CRP are increased due to inflammation |
question
| What is the most common cause of septic arthritis in young adults? |
answer
| N. Gonorrhoea |
question
| What is the role of pili in gonorrhea? |
answer
| Attachment Antigenic Variation |
question
| Gram negative diplococci that grow on Thayer Martin Agar must be: |
answer
| Gonorrhea (yeah!) |
question
| A 24 year old pharmacy student, who has failed at everything else in life, presents to your practice with migratory joint pain and a pustular rash on the extremities. You aspirate and joint and culture the aspirate. What are you likely to see on gram staining? |
answer
| COFFEE BEANS gonnorrhea |
question
| What are the symptoms of gonococcemia? |
answer
| Fever, MIGRATORY joint pain, suppurative arthritis, pustular rash on the extremities |
question
| Describe the rash associated with gonorrhea: |
answer
| Pustular rash with RED RING on the EXTREMITIES- no on the head, face, or trunk |
question
| What is the primary cause of prosthetic joint infections in the first 3 months after surgery? |
answer
| Staph aureus |
question
| What is the likely cause of prosthetic joint infections after 3-4 months? |
answer
| CoNS- Coagulase Negative Staph (often Staph Epi) |
question
| What is a likely cause of septic arthritis in IV drug users? |
answer
| Pseudomonas Aeruginosa |
question
| Officer Dwight comes into your primary care practice complaining of joint and bone pain that comes and goes. You gram stain and find nothing. He has a characteristic rash. Did I mention the joint pain comes and goes and is in more than one joint? What do you think he has? |
answer
| Lyme Disease- RECURRING POLYARTICULAR ARTHRITIS Borrelia Burgdorferi |
question
| A pharmacy student with gonorrhea has no idea what drug to use to treat it. What do you suggest? |
answer
| CEFTRIAXONE |
question
| How do we treat septic arthritis? |
answer
| Drain the joint Several Weeks IV of: Ceftriaxone for Gonnorhea Nafcillin/Oxacillin for MSSA Vanco for MRSA |
question
| How do we treat septic arthritis of a prosthetic joint? |
answer
| REMOVE AND REPLACE+ 6 weeks of antibiotics |
question
| If a patient has septic arthritis due to Staph Aureus, what else are they at risk for? |
answer
| Toxic Shock Syndrome |
