Mmbio 221 Final Exam Study Guide Questions and Answers 2024

Virulence characteristics, unique properties, and diseases caused by: Mycobacterium tuberculosis, - -virulent strains contain cord factor (cell wall component) which is necessary to cause disease -3 types: primary (results from initial infection), secondary (reestab. of active infection after period of dormancy), disseminated (when infection spreads thru body) -high risk ppl are those who contact infected persons and those with immunodeficiencies (HIV--combo has 90% chance of death) -diagnosed by xray showing infection in lungs, skin tests using PPD to see ppl with previous exposure have hard, red swelling -combo therapy used to treat (rifater, DOT, vaccine--BCG) Virulence characteristics, unique properties, and diseases caused by: Mycobacterium leprae - -transmitted person to person or thru break in skin -2 types: tuberculoid leprosy (high cell mediated response, low antibody; nonprogressive loss of sensation in hands) lepromatous leprosy (low cell mediated response; high antibody; produces gradual tissue destruction) -treated with combo of antimicrobials--dapsone rifampin (sometimes lifelong treatment) -prevented by avoiding exposure; some protection from BCG vaccine Virulence characteristics, unique properties, and diseases caused by: Mycobacterium ulcerans - -causes skin disease, beruli ulcer -associated with slow moving water, enters thru abrasions -produces lipid toxin, mycolactone that destroys subcutaneous tissue--makes clean huge ulcer on back or chest -must excise infected skin and use skin grafts Virulence characteristics, unique properties, and diseases caused by: Propionibacterium acnes - -treatment uses antimicrobials or no treatment is required -normal skin: only sebum reaches hair follicule and is discharged onto skin surface -blackhead: dead/dying bacteria and sebum form blockage -whitehead: inflammed skin swells over pore when bacteria infect hair follicule, accumulates bacteria and sebum -pustule: severe inflamm. of follicule causes this formation and rupture; producing cystic acne, which causes scar tissue The three types of antigens that are used to serotype enteric bacteria - O: outer membrane antigen K: capsular antigens H: flagellar antigens General characteristics of a coliform - -rapidly ferment lactose -part of normal microbiota -oportunistic pathogens (commonly found in soil; colonize intestinal tracts; presence in water indicates impure and poor sewage treatment) Virulence characteristics, unique properties, and diseases caused by: Brucella melitensis - -cuses STDs and abortive diseases -causes brucellosis --fluctuating (undulant) fever; --infected by being contaminated by dairy products or infected animal parts Virulence characteristics, unique properties, and diseases caused by: Bordetella pertussis - -msot important bordatella -causes pertussis/ whooping cough -most cases in children; inhaled in aerosols -attaches to ciliated epithelial cells thru 2 adhesions (filamentous hemagglutinin and perussis toxin) -produces 4 toxins: pertussin toxin (inc. mucus production), adenylate cyclase toxin (inc. mucus and inhibit leukocyte functions), dermonecrotic toxin ((constrict and hemorrhage blood vessels), tracheal cytotoxin (inhibits cilia movement and kills ciliated cells) -grown on Bordet-Gengou medium Virulence characteristics, unique properties, and diseases caused by: Bacteroides fragilis - -normal microbiota of intest and upper respiratory tract -most important bacteriode; involved in almost all gastrointest. disease -can be involved in abdominal infections, genital infections, wound infections Virulence characteristics, unique properties, and diseases caused by: Borrelia recurrentis - -causes epidemic relapsing fever -transmitted to humans by body lice -recurring episodes of fever and septicemia separated by symptom free intervals bc body trying to remove spirochetes Virulence characteristics, unique properties, and diseases caused by: Burkholderia mallei - -not found in environment -agent of glanders in horses also causes human infections may have evolved from pseudomallei -mallei and pseudom. are CDC select agents Virulence characteristics, unique properties, and diseases caused by: Bartonella Quintana - trench fever (WW1) -spread person to person by lice -causes diseases in weak immune ppl -symptoms include pain in long bones; headache fever (fever can return every 5 days) Virulence characteristics, unique properties, and diseases caused by: Pseudomonas aeruginosa - -rarely part of normal microbiota -opportunisitc pathogen of weak immune ppl -can form hot tubitis (dots in skin) -can colonize almost every organ and system and result in various diseases -often infects lungs of cystic fibrosis patients (forms biofilm that protects from phagocytosis and inc. likelihood of death) -infects severe burns -produces pyocyanin, blue-green pignemnt and fruity odor -hard to treat bc resistant to drugs Virulence characteristics, unique properties, and diseases caused by: Salmonella typhi - -causes typhoid fever -invade M cell; passes thru cell and multiplies in macrophages in lymph nodes and other sites; causes apoptosis