Module 2 Study Guide/Module Questions Flashcards
What is the first rule of antimicrobial therapy?
Match the drug to the bug!
Define narrow-spectrum antibiotics? What’s an example?
Agents that act against a single or limited group of microorganisms. Example: Isoniazid works against tuberculosis exclusively. Penicillin.
Define broad-spectrum antibiotics? What is an example? What are you at risk for by using them?
Agents that are effective against a wide variety of microbial species. Example: Tetracycline. Note: Broad-spectrum antibiotics are the most likely to cause superinfection of an organism such as candida infection.
What are some tricks to knowing if a bacteria is Gram positive?
Bacteria starting with staph, strep or Enterococci.
Generally infections above the belly button.
What is the Black Box warning associated with floroquinolones?
Tendon rupture
A patient with a Type I Penicillin reaction has a _______% chance of crossing reacting with _________?
A patient with a Type I Penicillin reaction has a .17-8% chance of crossing reacting with a cephalosporin.
What is a Beta-Lactam?
a ring in the chemical structure of certain antibiotics including PCN, cephalosporins, and related compounds. The beta-lactam antibiotics exert their effect by interfering with the structural crosslinking of peptidoglycans in bacterial cell walls.
What is Beta-Lactamase?
An enzyme that some bacteria have that breaks apart the beta-lactame ring on certain antibiotics to keep them from working.
What antibiotic has many drug-to-drug interactions and what drugs should be avoided while taking?
Clarithromycin (Biaxin) should not be taken with statins or calcium channel blockers (can cause kidney injury)
What patient should NOT be prescribed Fluoroquinolones? What is the risk?
Patients with peripheral atherosclerotic vascular disease, hypertension, Marfan’s syndrome, and the elderly due to the increased risk of aortic aneurysm.
What are some serious side effects of flouroquinolones?
Adverse: Increased risk of tendon rupture in certain patients.
Side effects:
1) decreases in blood sugar
2) anxiety, confusion, and depression
3) non-reversible peripheral neuropathy
4) hepatotoxicity,
5) hematologic disorders
6) seizures,
What serious adverse effect is associated with Trimethoprim-sulfamethoxazole (TMP-SMX)? What concurrent drug increased this risk? What type of patients increases this risk?
Hyperkalemia and sudden cardiac death.
The use of TMP-SMX with angiotensin-converting inhibitors or angiotensin receptor blockers increases the risk. Elderly patients and those with kidney disease are most at risk.
What drug class is most commonly prescribed to pregnant patients?
Antibacterials
What two antibiotic types are second-line treatment in pregnancy if the first line is not effective?
Nitrofurantoins (macrobid) and sulfanomides.
Macrobid is the best choice of these two.
What are the three first-line antibiotics in pregnancy?
PCN, macrolides, cephalosporins
When should sulfonamides be avoided in pregnancy and why?
In the first and third trimesters (unless there is no other option). They inhibit folate metabolism and increase the risk of cardio defects and cleft defects. In the third trimester, they increase the risk of hyperbilirubinemia and kernicterus.
What antibiotic is contraindicated in pregnancy and why?
Tetracyclines (ex docycycline and minocycline) due to fetal tooth defects.
Which antibiotics are considered safe during breastfeeding?
PCN and cephalosporins (some consider macrolides safe)
What is a serious secondary GI infection that is related to antibiotic therapy in general? How do we prevent it?
C. Diff. Match the drug with the bug!
The four antibiotics that are most likely to cause C. diff are imipenem, ceftazidime, clindamycin, and moxifloxacin. Broader the spectrum of the antibiotic, the more likely it is to cause C. diff. This is because broader spectrum agents kill off intestinal flora and allow C. diff to get a head start.
What is the most severe reaction to sulfanomides? What type reaction is this?
The most severe hypersensitivity reaction to sulfonamides is Stevens-Johnson syndrome. Type 4-delayed onset 48-72 hrs. with Morbilliform rash.
What type of reaction is more common with PCN than any other family of drugs? What could cause people to think they are allergic to PCN when they may not be?
Type 1 severe allergic reactions. IgE mediated, Immediate hypersensitivity on the second exposure. Hives are an indication.
They received PCN as a child and had a rash-you can develop a rash with PCN if you have a virus. This is not an allergic reaction.
Which antibiotics in this module prolong Qt interval?
Macrolids: azithromycin, clarithromycin, erythromycin
Ciprofloxacin, levofloxicin, moxifloxacin
chloroquine
flucanazole, pentamadine
What are the four mechanisms microbes have for resisting drugs?
1) Chromosomal mutation
2) Inductive expression of a latent chromosomal gene
3) Exchange of genetic material through transformation (exchange of DNA)
4) Jumping Genes-enter transmissible plasmids or chromosomes.
What is antimicrobial stewardship? Why is it important?
The effort to measure and improve how antibiotics are prescribed by clinicians and used by patients. Critical to effectively treat infections, protect patients from harm, and combat antibiotic resistance.
How do antivirals work?
Reducing viral shedding and reducing viral count. They block entry into the cells preventing reproduction and shedding
What are the significant concerns with oral antifungals (azole)?
Hepatotoxicity, QT prolongation, drug-to-drug
The main concern with oral antifungals, specifically the azole antifungals, is their inhibition of the CYP450 enzymes which can result in drug-to-drug interactions when other drugs using the CYP450 system are taken concurrently. The statins are contraindicated with many of the azole antifungals.
What is the relationship between the onset of viral illness and antivirals?
most effective if given within the first 48 hours of onset (ex. influenza). These medications can shorten the duration of fever and illness symptoms and may reduce the risk of complications. The medications do not cure but simply reduce the severity of the symptoms.
Who is recommended to get a flu vaccine? how often?
Annual Flu vaccination is recommended for people 6 months old and older who do not have contraindications.
What is PrEP? What are the important teaching considerations when ordering PrEP? What lab monitoring is necessary for PrEP?
Pre-Exposure prophylaxis for HIV (ex. Truveda)
Teaching: The patient must be HIV negative always. Test prior to starting and every three months.
Must take daily. missing doses could increase the risk for drug-resistant HIV.
Labs: HIV testing, other STDs, kidney and liver function, pregnancy test.
Is oral fluconazole (Diflucan) safe in pregnancy and lactation?
In small doses (I.e. 150 mg PO) Diflucan is considered safe. However, higher doses or prolonged exposure are associated with congenital anomalies. Fluconazole is considered compatible with breastfeeding as exposure is less through the breastmilk than those doses considered safe for neonates. When other treatments fail to treat breast candidiasis, oral fluconazole is often prescribed for both mother and baby.
What types of vaccines cannot be given in pregnancy and why?
Only live vaccines have the potential to cause illness. Live vaccines are contraindicated in pregnancy. Because of the potential for viral shedding of the live vaccine, the provider must also consider close contacts and caregivers of patients who may be considering the live vaccine.
Which antifungal/antiviral drugs discussed prolong QT?
Antimalarial: chloroquine
Antifungal: fluconazole, and pentamidine.
