Term
| The chronic phase of hepatitis is responsible for most morbidity and mortality, can cause fibrosis and cirrhosis, with an increased risk for hepatocellular carcinoma. Which hep viruses have a chronic phase? |
|
Definition
| B, C, D, G, all enveloped |
|
|
Term
| Name the virus with the following features - released by exocytosis, shedding 10 days prior to symptoms, enters blood via GI, Fever, fatigue, nausea, loss of appetite and abdominal pain, self-limited, jaundice. |
|
Definition
|
|
Term
| T or f: The hep a vaccine is an inactivated whole virus. |
|
Definition
|
|
Term
| In diagnosing HAV the IgM is positive for ________ months and the IgG is positive for ________. |
|
Definition
|
|
Term
| How is HEV different from HAV? |
|
Definition
| Higher mortality, affects more women, no vaccine |
|
|
Term
| Which virus causes 90% of gastroenteritis in US? |
|
Definition
| Norwalk, +ssRNA; rotavirus also causes GE |
|
|
Term
| How are rotavirus and Norwalk different from each other since they both cause diarrhea? |
|
Definition
| Rota is a child disease passed person-2-person via fecal oral; Norwalk is adult passed fecal via food |
|
|
Term
| The the live pentavalent human-bovine virus reassortment rotavirus vaccine prevents what disease? |
|
Definition
|
|
Term
| Which virus has these features - dsRNA, non-enveloped, 10-12 RNAs, double layered capsid, highly infectious and causes infantile diarrhea? |
|
Definition
|
|
Term
| What is the research test for HAV? |
|
Definition
| Virus in feces by electron microscopy, PCR |
|
|
Term
| Which hep virus takes the longest to move out of the incubation period? |
|
Definition
| Hep b, with a range of 45-160 days; although most start at 15 days, hep c is second place |
|
|
Term
| What is the difference between pre-icteric and icteric phase of acute infection of hep virus? |
|
Definition
| Pre = prodrome symptoms of malaise, fatigue, fever, weight loss; icteric - jaundice with elevated bilirubin, decrease in clotting factors, rise in ALT>AST |
|
|
Term
| Which virus has these features - circular, partly dsDNA, has surface/core/preprotein antigens, heat stable, parenteral transmission by prevalence, exocytosis of virions. |
|
Definition
|
|
Term
| If a person only has a mild acute hep b infection what is likely to occur in regards to their hep b status? |
|
Definition
| Likely become chronically infected |
|
|
Term
| The phases of chronic HPV include a replicative and non-replicative phase, but what is significant about the HBeAg/Ab as the phases progress? |
|
Definition
| The Ag becomes negative and the Ab becomes positive due to viral clearance |
|
|
Term
| What is the Hep B vaccination consist of? |
|
Definition
|
|
Term
| What virus has these features - ssRNA circular, needs HBV for life cycle, parenteral (mostly drug), additive to inflammatory response, increase fulminant hepatitis, detected via Ag/Ab, no vaccine. |
|
Definition
|
|
Term
| Name the virus with these features - +ssRNA, parenteral, majority of infections are asymptomatic, high rate of chronic infections, no vaccination. |
|
Definition
|
|
Term
| What is the difference in Hep C Ab serology in acute and chronic infection? |
|
Definition
| Acute- Ab negative; Chronic - Ab positive |
|
|
Term
| Name the virus with these features - 30% homology to HCV, flavivirus, parenteral, high rate with HCV infection, does not cause hepatitis, protective against HIV while replicating in CD4 cells. |
|
Definition
|
|
Term
| The influenza antivirals are called what and what is their method of delivery? |
|
Definition
| Oral - Amantidine, rimantidine; inhaled - zanamivir, oral - oseltamivir |
|
|
Term
| What is the mechanism for influenza a only antivirals and why do they only work for flu A? |
|
Definition
| they inhibit the M2 protein from acidifying endosomes and allowing viruses to uncoat; other flu viruses don’t use M2 |
|
|
Term
| What is the mechanism for the influenza A/B antivirals? |
|
Definition
| both drugs are structural analogs of neuraminic acid. Inhibition of the viral neuraminidase of influenza A and B prevents the release of viral particles from infected cells, thus interfering with the spread of viral infection |
|
|
Term
| Define ribavirin’s mechanism of action and bioavailability. |
|
Definition
| Ribavirin is broad spectrum antiviral that is a guanosine analogue and thus interrupts viral mRNA formation and protein synthesis. It is available oral or IV and in all tissues except CNS |
|
|
Term
| The following drugs are good IV antivirals, identify their good oral counterparts - acyclovir, penciclovir, ganciclovir. |
|
Definition
|
|
Term
| What is the mechanism of action of acyclovir and at what stage is resistance developing? |
|
Definition
| Acyclovir becomes phosphor’d 3 times and enters a viral dna strand since it is a deoxguanosine analogue causing chain termination and the bad mRNAs inhibit viral DNA polymerases; resistance is developing through mutated thymidine kinase |
|
|
Term
| What two drugs are used for suppressive therapy for HSV outbreaks and shingles? |
|
Definition
| Valacyclovir, famciclovir |
|
|
Term
| What drug is a topical treatment for herpes labialis? |
|
Definition
|
|
Term
| Which drug is used for the prophylaxis and treatment of CMV with toxicities related to bone marrow suppression? |
|
Definition
|
|
Term
| Foscarnet is an IV drug that is used for resistant HSV and CMV strains, but what is its mechanism of action? |
|
Definition
| It is an inorganic phosphate analogue that binds to dna polymerases so that they cannot cleave pyrophosphates |
|
|
Term
| Trifluridiine, fomivirsen, cidofovir are antivirals that treat what disease caused by CMV? |
|
Definition
|
|
Term
| IFN-a, Lamivudine, telbivudine, adefovir, entacavir are all Hep B drugs that work through what mechanism? |
|
Definition
| They are nucleoside analogues that inhibit DNA polymerases and reverse transcriptases; lamivudine is used first, and the others are used against resistant strains |
|
|
Term
| T or F: Ribavirin is FDA approved for RNA infections like measeles and hantavirus; Cidofir is FDA approved for DNA infections like papovavirus and variola. |
|
Definition
| False, neither is approved, but they are still used |
|
|
Term
| Imiquimod and Podofilox are both used for what virus and disease? |
|
Definition
| Papillomavirus and anogenital and common warts |
|
|
Term
| Name the virulence factor with these features (Gm-)- toxins are directly translocated from the cytoplasm of the bacterial cell to the cytoplasm of the target mammalian cell like a needle, and are not subject to antibody-mediated neutralization. |
|
Definition
|
|
Term
| Name the virulence factor with these features (Gm-)- the polypeptide chains that comprise the toxin are secreted across the cytoplasmic and then outer membranes in separate steps to have the toxin enter via endosomes. |
|
Definition
|
|
Term
| What are the two functions of pili? |
|
Definition
| Sex pili, and adhesive functions |
|
|
Term
| ____________ ________ are extracellular, usually consist of polysaccharides, and frequently function to inhibit phagocytosis. Capsular polysaccharides are often important components of vaccines against bacterial pathogens. |
|
Definition
| Bacterial capsules that can be Gm+/- |
|
|
Term
| _________ ___________ are metabolically inert and are resistant to environmental insults and can survive desiccation, freezing, radiation, etc. |
|
Definition
|
|
Term
| What is the difference between the envelope of Gram - and + bacteria? |
|
Definition
| Gm+ has a thick cell wall on the outside and has covalently attached teichoic acids, Gm- has thin cell wall and an outer lipid bilayer |
|
|
Term
| What are the 3 major targets for antibiotics? |
|
Definition
| Cell wall, supercoiling enzymes, and ribosomes |
|
|
Term
| What type of antibiotics inhibit cross-linking of the peptidoglycan cell wall structure of bacteria? |
|
Definition
|
|
Term
| The LPS or lipopolysaccharide proteins on the outer leaflet of the outer lipid bilyer of Gm- bacteria is known as _________ that can cause septic shock. |
|
Definition
|
|
Term
| Which of these molecules are PAMPs - Lipid A, TA, LTA, CW? |
|
Definition
|
|
Term
| What is the difference between horizontal and vertical gene transfers? |
|
Definition
| Horizontal is DNA transfer from one bacteria to another, vertical is mother to daughter cell |
|
|
Term
| T or F: pathogenicity islands are DNA acquired by bacteria via horizontal gene transfer. |
|
Definition
|
|
Term
| In bacteria what does competence refer to? |
|
Definition
| The ability to take up DNA, either naturally thru molecular mechanisms on the surface of the membrane or a bacteria’s membrane can be destabilized to allow it to happen, either way can allow for homologous recombination |
|
|
Term
| T or F: At a low frequency during lytic growth, bacteriophage can package large segments of the host cell chromosome instead of phage DNA. Subsequent infection delivers the DNA to a new bacterial cell. |
|
Definition
| True, it is called gene transduction |
|
|
Term
| What is the difference between the lytic and lysogenic cycle in temperate bacteriophages? |
|
Definition
| Lytic is the normal viral reproduction cycle, but lysogenic is when the viral dna is incorporated into the bacterial DNA and then daughter generations have those genes. |
|
|
Term
| What is the bacterial element with these features - Extrachromosomal elements capable of autonomous replication, circular, The rate of the initiation of DNA replication is subject to self control, contain loci that encode sex pili and proteins required for DNA transfer from donor to recipient cells. |
|
Definition
|
|
Term
| ______________ are mobile genetic elements that are able to move from one genome to another and are completely dependent on the host replicon for replication. |
|
Definition
|
|
Term
| Which of the following are pathways for antibiotics resistance development - enzymatic inactivation/modification, active efflux, decreased permeability, mutated target gene. |
|
Definition
|
|
Term
|
Definition
| Where the destruction of one microbe allows another to flourish |
|
|
Term
| T or F: a drug may be bactericidal against one bacteria and bacterstatic against another. |
|
Definition
|
|
Term
| T or F: all strains of s. aureus are pathogenic. |
|
Definition
|
|
Term
| Describe the morphology and metabolism of staph aureus and the two biochem tests that it return a positive result. |
|
Definition
| Gram positive, yellow round clusters, anaerobe that ferments glucose, both catalase and coagulase positive |
|
|
Term
| What is the hallmark of staph infection? |
|
Definition
|
|
Term
| What are the common sites of colonization of s. aureus and how can it be spread? |
|
Definition
| Nasopharynx, skin, perineal area; contact with skin, fomites, aerosols |
|
|
Term
| Explain why each of the structures of s. aureus are virulence factors - capsule, peptidoglycan, teichoic acid, protein A, cytoplasmic membrane. |
|
Definition
| Inhibits chemotaxis and phago and facilitates adherence to synthetic material, endotoxin that stims pyrogens and complement, mediates attachment to mucosal surfaces and creates immune response, binds Fc receptor of IgG preventing clearance. |
|
|
Term
| Why is it that the following enzymes are considered virulence determinants of staph a - penicillinase, hyaluronidase, catalse, coagulase, fibrinolysin? |
|
Definition
| They promote bacterial spread or destroy antibiotic effectiveness |
|
|
Term
| S. aureus can cause which of the following diseases - cutaneous, endocarditis, bacteremia, pneumonia, septic arthritis, osteomyelitis, vascular device infection. |
|
Definition
|
|
Term
| Staph Scalded Skin Syndrome and localized bullous impetigo are cutaneous disease caused by what staph a. exotoxin? |
|
Definition
| Exfoliative exotoxin A and B which targets desmoglein-1 which hold together keratinocytes, resolved by antibody development |
|
|
Term
| T or F: staph food poisoning is the result of a heat stable, digestion resistant, exotoxin that is preformed and not from a direct effect of the bacteria. |
|
Definition
| False, enterotoxin. Foods include ham, pork, potato salad, cream pies, ice cream |
|
|
Term
| Toxic shock syndrome is caused by s. aureus and s. pyogenes due to the TSST-1 toxin, what are the 4 key features of TSS? |
|
Definition
| Fever (38.9C), hypotension, diffuse rash and desquamation |
|
|
Term
| TSST-1 is an exotoxin and a superantigen, what is a superantigen? |
|
Definition
| A toxin that causes stimulation of up to 20% of t-cells via the TCR without the need of an antigen in the MHC |
|
|
Term
| S. epidermis is a coagulase negative, less virulent version of S. aureus, what types of infections does it cause? |
|
Definition
| Infectects artificial heart valves, prosthetic joints, catheders, other prosthetic devices. |
|
|
Term
| Penicillin binding protein PBP produces the peptidogylcan cross-linking in bacterial cell walls, how is MRSA different? |
|
Definition
| It has a mec-A gene that produces a PBP-2a that only weakly binds methicillin. |
|
|
Term
| T or F: CA-MRSA and nosocomial MRSA are the same bacteria. |
|
Definition
| False; CA-MRSA is different and it is PVL-gene positive and TMP-SMX sensitive |
|
|
Term
| What is the mechanism of action for MRSA drugs daptomycin and linezolid? |
|
Definition
| Daptomycin depolarizes the bacteria via a K+ channel insertion, Linezolid inhibits protein synthesis |
|
|
Term
| 90% of strep diseases are due to which group? |
|
Definition
|
|
Term
| Identify the bacteria with these features - Gm+, non-spore forming, non-motile, fastidious anaerobe, encapsulated, complete hemolysis on blood agar, catalase negative. |
|
Definition
|
|
Term
| Identify the bacteria with these features - Gm+, non-spore forming, non-motile, fastidious anaerobe, non-capsulated, partial or incomplete hemolysis on blood agar, catalase negative. |
|
Definition
| Strep viridans and enterococci |
|
|
Term
| T or F: Strep pyogenes can either cause asymptomatic colonization or pharyngitis/skin infection which are all self-clearing. |
|
Definition
|
|
Term
| Which of the following are true about the surface virulence factors of S. Pyogenes - non-immunogenic capsule of hyaluronic acid, protein f attaches to fibronectin in tissues, M protein exerts anti-phagocytic activity in the absence of type-specific antibody and stimulates type-specific protective immunity. |
|
Definition
|
|
Term
| What is the difference between streptolysin O and S, the secreted virulence factors from strep pyo? |
|
Definition
| O is heat and oxygen labile and lyses PMNs and hemolytic that is antigenic, S is oxygen stabile and lyses PMNs and hemolytic but not antigenic |
|
|
Term
| Which of the following enzymes are secreted virulence factors from Strep pyo - DNases which hydrolyze DNA in pus, streptokinase which dissolve clots via plasmin, or C5 peptidase which cleaves complement. |
|
Definition
|
|
Term
| What are the 3 groups of exotoxins from strep pyo that are superantigens responsible for the rash in scarlet fever and are responsible for septic shock? |
|
Definition
| Spe A and B which are phage encoded, and C which is chromosomal |
|
|
Term
|
Definition
|
|
Term
| T or F: group a strep pharyngitis is mainly in children but complications can result in spread to sinus, ear, lungs, blood, or cause glomerular nephritis. |
|
Definition
|
|
Term
| Differentiate the depth of skin involvement in the following strep pyo skin infections - impetigo (pustules in exposed areas on kids), erysipelas (well-demarcated), cellulitis (indistinct demarcation), and necrotizing fasciitis. |
|
Definition
| Epidermis, epi and dermis, epi/dermis/subcu, epi/dermis/subcu |
|
|
Term
| What is the diagnosis and treatment choices for group a strep? |
|
Definition
| Diagnosis with culture and anti-strepolysin O with antigen detection that is highly sensitive; treatment is penicillin |
|
|
Term
| T or F: strep a pharyngitis can cause acute rheumatic fever, and both throat and skin infections can result in acute glomerular nephritis. |
|
Definition
|
|
Term
| Why is it important to screen pregnancies for Group B strep? |
|
Definition
| It is a common cause of newborn disease and via genitourinary carriage which can cause sepsis, pneumonia, or meningitis |
|
|
Term
| Which bacteria is notoriously antibiotic resistant, commonly infects in hospitals via contact or antimicrobial treatment or catheter placement causing UTI/septicemia/endocarditis, but is part of normal bowel flora? |
|
Definition
|
|
Term
| Both sulfonamides (PABA analogue) and trimethoprim (competitive DHFR inhib) block folate synthesis, but which is bacteriostatic and which is bactericidal? |
|
Definition
| Sulfonamides are bacteriostatic, and trimethoprim kills bacs |
|
|
Term
| T or F: sulfonamides are now used against MRSA, widely against gram+/-, but has limited activity against group a strep and enterococci. |
|
Definition
|
|
Term
| Which of the following are key properties of sulfonamides - highly protein bound, hepatic metab, and renal elimination. |
|
Definition
|
|
Term
| Which of the following are adverse affects of sulfonamides - kernicterus (bili in brain), crystalluria, hematopoietic disturbances, or hypersensitivity syndromes? |
|
Definition
|
|
Term
| Why do clinicians use combination drugs composed of both sulfonamides and trimethoprim (bactrim aka cotrimoxazole)? |
|
Definition
| Because they have a bactericidal action that blocks folate acid synthesis at two points in the enzymatic pathway creating a synergistic affect. |
|
|
Term
| Which of the following are b-lactam antibiotics which inhibit cell wall synthesis at the transpepidation stage - penicillin, cephalosporins, carbapenems, monobactams. |
|
Definition
|
|
Term
| What are the 3 causes of resistance to beta-lactam antibiotics? |
|
Definition
| Degradation by bacterial beta-lactamase (inhibitors exist though), decreased drug permeability, altered penicillin binding proteins |
|
|
Term
| T or F: Vancomycin and bacitracin are non ? lactam drugs that also inhibit cell wall synthesis. |
|
Definition
|
|
Term
| T or F: Natural Penicillins: Pen G, Pen VK, Benzathine and Procaine forms are the Drug of choice for Streptococcal infection, syphilis, spirochetes but are Highly susceptible to beta lactamases. |
|
Definition
|
|
Term
| T or F: Antistaphylococcal Penicillins: Methicillin, oxacillin, dicloxacillin…are More stable to beta lactamases, due to modifications near beta lactam ring and have Poor entry into gram negative bacteria. |
|
Definition
|
|
Term
| T or F: Amino Penicillins: Ampicillin, amoxicillin, others… have Enhanced Gram negative coverage (due to amination) and Remain highly susceptible to beta lactamases. |
|
Definition
|
|
Term
| T or F: Antipseudomonal Penicillins: Carbenicillin, Ticarcillin, Piperacillin… have Enhanced Gram negative coverage (due to extensive side chain addition) and are Highly susceptible to beta lactamases. |
|
Definition
|
|
Term
| Which of the following are toxicities related to beta-lactams - hypersensitivity, NVD, neutropenia, GI: psuedomembranous enterocolitis or antibiotic diarrhea, neuro/cation toxicity. |
|
Definition
|
|
Term
| How are penecillins delivered to a patient? |
|
Definition
| Iv or IM, although amoxicillin is well-absorbed via GI |
|
|
Term
| T or F: Penicillins enter the CSF just as well as the serum. |
|
Definition
| False, it widely distributes in tissues but doesn’t enter the CNS unless there is inflammation |
|
|
Term
| How do cephalosporins work differently from penicillins? |
|
Definition
| They don’t, they both bind the PBP |
|
|
Term
| Beta-lactamase inhibitor drugs do not have intrinsic anti-bacterial activity unless combined with a beta-lactam drug, do those combo drugs have comparable activity against staph as methicillin? |
|
Definition
|
|
Term
| T or F: NONE of the cephalosporins are active against enterococci, coagulase negative staphylococci, or Listeria monocytogenes. |
|
Definition
|
|
Term
| What is the difference between spores and anaerobic bacteria? |
|
Definition
| Spores are DNA containing structures that are extremely tough that can create a cell, whereas anaerobes are already formed cells that cannot grow in the presence of oxygen and having varying levels of tolerance to it. |
|
|
Term
| Name the bacteria with these features - gram positive rod, anaerobe, creates H2S and CO2, cause gas gangrene due to alpha and beta toxin, food poisoning spores cause growth and release enterotoxin, alpha toxin is lecithinase (phospholipids), beta toxin is responsible for necrotizing enteritis. |
|
Definition
|
|
Term
| Name the bacteria with these features - gram + rod, forms terminal spores, found in soil, tetanolysin (hemolysis)toxin, causes lockjaw and muscle spasm, highly sensitive to oxygen, tentanospasmin cleaves to A and B which block inhib neurotrx that is irreversible. |
|
Definition
|
|
Term
| Name the bacteria with these features - gram + rod, forms spores that are heat resistant, toxins are heat sensitive and due to vegetative growth, disease of Ach inhib is a result of toxin intoxication not bacterial destruction, growth in absence of normal flora (kids). |
|
Definition
|
|
Term
| Name the bacteria with these features - gram + rod, forms spores, causes antibiotic resistant GI disease such as diarrhea and psuedomem colitis due to toxins A and B, treated by oral metronidazole or vancomycin, fecal-oral or nosocomial transmission. |
|
Definition
|
|
Term
| Name the bacteria with these features - gram + bacillus, no spores, aerobic, leathery skin pseudomembrane in pharynx, damage due to phage encoded A and B toxin that inhibits cell protein creation, treated with penicillin and prevented with vaccine. |
|
Definition
| Corynebacterium diphtheriae |
|
|
Term
| Name the bacteria with these features - gram +, aerobic, spores, two toxins that exist in rice one that is pre-formed and the other is a heat labile toxin due to bacterial growth, diseases caused are vomiting and diarrhea. |
|
Definition
|
|
Term
| Name the bacteria with these features - Gram positive filamentous bacilli, spores, anaerobes, a chronic granulomatous lesion in the sinuses can form, Yellow “sulfer granules” sometimes appear in the abscesses, colonizes UR tract/GI/Female genital tract. |
|
Definition
|
|
Term
| Know the Hep B serology for diagnosis. |
|
Definition
|
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