CIC EXAM STUDY SET QUESTIONS AND ANSWERS/ GRADED A+(UPDATED)

CIC EXAM STUDY SET QUESTIONS AND ANSWERS/ GRADED A+(UPDATED) Chain of Infection - CORRECT ANSWER-1)Infectious agent= organism with ability to cause disease; greater virulence, invasiveness, and pathogenicity = increased odds of infection 2) Reservoir: place where microbes can persist and reproduce 3) Portal of Exit: way for microbe to leave the reservoir 4) Mode of transmission: method of microbe transfer from one place to another 5) Portal of entry: opening that allows microbe to enter host 6) Susceptible host: Lacks immunity or physical resistance to prevent invasion by microbe Is a circle; each link must be present in sequential order for infection to occur Virulence - CORRECT ANSWER-Measure of microbe's ability to invade and create disease Depends on ability to: Survive in environment between hosts Transmit between hosts (moving; adherence) Proliferate IgM - CORRECT ANSWER-Pentamer; primary response, short-lived (6 months); best at fixing complement IgG - CORRECT ANSWER-Monomer; main blood antibody, secondary response; longer lived. opsonization and toxin neutralization. 4 subclasses Physical barriers - CORRECT ANSWER-Skin; fever; secreted antimicrobials; innate immunity Complement system - CORRECT ANSWER-11=protein cascade; classically activate by ab:ag complexes; alternate by pathogen surfaces Skin defects; examples and associated pathogens - CORRECT ANSWER-Wounds, burns, trauma, serious derm problems, indwelling devices, injections. Skin flora- S. aureus, CNS, strep pyo, corynebacteria, malassezia furfur Mucous membrane barrier defects; examples and associated pathogens - CORRECT ANSWER-chemo-induced mucositosis, head/neck trauma, smoking, inhalational injury, antacids/PPIs. Resident flora- anaerobes, aerobic GNR, candida, enteroccus, bovis Body passage obstruction; examples and associated pathogens - CORRECT ANSWER-Tumors, foreign bodies, stones, cystic fibrosis. Resident flora overgrow or invade; site-specific. Abnormal number or function of granulocytes - CORRECT ANSWER-Leukemia, chemo, congenital disorders, diabetes. If short term ( 2 wks) then aerobic GNR, Sa, CoNS. IF long term, add fungi (candida, t. glabrata, aspergillus) Abnormalities of cell-mediated immunity - CORRECT ANSWER-BMT, HIV, steroids, malnutrition, 3rd tri pregnancy. Bacteria: Intracellular pathogens (listeria, salmonella, mycobacteria, nocardia, legionella). Fungi: candida, Cryptococcus, coccidioides, histoplasma. Virus: Herpes group Also toxoplasma and strongyloides. abnormalities of humoral immunity - CORRECT ANSWER-BMT, HIV, some cancers, aging. Strep pneumo, encapsulated H. flu, Neisseria meningitidis Preventing infection for immunocompromised patients - CORRECT ANSWER-Take thorough patient history. Prepare before starting with all vaccines, procedures, line placement, screening. Support gastric acidity. Prevent exposures with awesome hygiene, approp food and water precautions, visitor education, no flowers or plants, and possible abx prophy (for infections that might reactivate or high-risk for pneumocystis) Mycoplasma spp. - CORRECT ANSWER-No cell wall -- limited abx choices. Cause atypical pneumonia. Usually diagnosed by serology Chlamydiae - CORRECT ANSWER-obligate intracellular parasites. Elementary body=infectious, reticulated= intracellular. DFA or ELISA for detection of antigen is most common. Can also detect antibodies. Rickettsiae - CORRECT ANSWER-obligate intracellular parasites. arthropod vectors. Rarely culturing; detected by serology using ELISA for antibodies. Textbook viral replication cycle - CORRECT ANSWER-1. Attachment 2. penetration/entry 3. replication 4. maturation/assembly 5. release Sensitivity - CORRECT ANSWER-% of true + who test +; inherent to test Specificity - CORRECT ANSWER-% of true neg who test neg; inherent to test PPV - CORRECT ANSWER-Likelihood that a + test represents a true case (% T+/all+); depends on the test and on prevalence of disease in population NPV - CORRECT ANSWER-Likelihood that a negative test result is a true non-case (%TN/allN); depends on test and population prevalence