PHAR6724 Infectious Disease Exam #3
Salmonella typhi
1 serotype. Typhoid fever with symptoms including rash, diarrhea, headache, exhaustion, and bacteremia. Invades by crossing Peyer's patches and is spread systemically by phagocytes
Streptococcus pyrogenes: group type
A
Anaplasma (Ehrlichia) phagocytophilum
Anaplasmosis (human granulocytic ehrlichiosis) - common signs include rapid fever, chills, headache, myalgia, leukopenia, and thrombocytopenia - infects granulocytes. Natural host is the white-footed deer mouse and is carried by deer tick
Clostridium difficile (C. diff) in colon
Antibiotic associated diarrheas - pseudomembranous colitis: cytotoxins kill enterocytes; white membrane ulcer in epithelium. Risk factors include use of PPIs, older age, antibiotic therapy, recent hospitalization, chemotherapy, chronic kidney disease, and feeding tube. Treated with fecal transplant
Helicobacter pylori (H. pylori)
Associated with gastric and duodenal ulcers/gastritis. Uses flagella to get away from stomach acid, uses urease to break down urea to NH4 and CO2, reacts with H20 to form bicarb, increasing stomach pH. The cytotoxin and ammonia can destroy mucus-producing cells, exposing underlying connective tissue to stomach acid, leading to inflammation and/or bleeds
Streptococcus agalactiae: group type
B
Moraxella catarrhalis in respiratory tract
Bronchitis and sinusitis in children, major cause of otitis media, bronchopneumonia happens in older adults
Proteus vulgaris and mirabilis
Commensal - Urinary tract infections - urease cleave urea in urine influencing pH and causing formation of stone - highly motile
Kiebsiella pneumoniae
Commensal - Urinary tract infections and pneumonia, no flagella and found in large intestines, soil, and water
Streptococcus bovis: group type
D
Corynebacterium diphtheriae of the throat/respiratory tract
Diphtheria: signs and symptoms include sore throat, fever, exudative pharyngitis with thick pseudomembrane - can cause advanced toxigenic symptoms like congestive heart failure, paralysis of cranial nerves, and death. can be transmitted by inhalation or skin contact. colonized in throat. treated with diphtheria antitoxin and antibiotics. has an effective vaccine
Bacteroides fragilis
Endogenous infection: occurs intra-abdominally from surgery/trauma and causes abscess in the colon. Is an aerobic, non-spore forming rod and predominant organism in colon
Campylobacter jejuni
Enterocolitis - foul-smelling, watery diarrhea accompanied by blood and severe abdominal pain. Transmitted through fecal-oral route in food, such as poultry and unpasteurized milk
Chlamydia trachomatis in the birth canal/vagina/rectum/penis - trachoma
Eye infection in infants which is the leading cause of blindness worldwide. Spread by flies and hand-to-eye contact
Clostridium botulinum in neurons
Floppy baby syndrome (hypotonia) botulinum toxin can pass from gut into circulation where it is taken up by axons which block neurotransmitters causing flaccid paralysis of striated muscles
Clostridium botulinum in GI tract
Food poisoning - found in canned foods and is heat labile with a high mortality
Staphylococcus epidermidis: skin/prosthetics/artificial joints
Forms biofilm that is a virulence factor. Capsule surrounding the pathogen is also a virulence factor which helps with adherence and avoiding antibodies
Haemophilus influenzae
Gram negative rod - Endotoxin and antiphagocytic capsule are virulence factors. causes otitis media, sinusitis, bronchitis/pneumonia, meningitis, and epiglottitis by colonizing upper respiratory tract mucosa
Legionella pneumophila
Gram negative rod - Facultative, aerobic intracellular pathogen that normally lives in soil and water and is transferred through water droplets. It causes Legionnaire's disease, a serious type of atypical pneumonia
Bordetella pertussis
Gram negative rod - Pertussis (whooping cough) caused by attachment of bacteria to ciliated epithelium in upper respiratory tract and kills ciliated cells
Escherichia coli (E. coli)
Gram negative rod that causes pneumonia, meningitis, diarrhea, dysentery, hemolytic uremic syndrome, and most UTIs. Most abundant facultative anaerobe in colon/feces with 3 antigens (O - cell wall, H - flagella, and K - capsule)
Streptococcus
Gram positive, cocci-shaped, facultative, coagulase negative
Staphyloccocus
Gram-positive, cocci shaped facultative anaerobes
Yersinia pestis (plague)
Highly infectious with high person-person spread. responsible for bubonic (caused by flea bites and has swelling buboe) and pneumonic plague (spread by bacteria through blood to cause plague meningitis)
Enteropathic E. coli (EPEC)
Infant diarrhea - attaches to small intestinal mucosal cells and destroys microvilli
Neisseria meningitidis in respiratory tract
Meningitis - can be transmitted through inhalation and spreads to the meninges and brain. Meningococcemia is a rare case of pathogen infection and can see also necrosis of skin. Polysaccharide capsule is target for vaccine. Endotoxin (shock LPS), pneumonia, and arthritis.
Pseudomonas aeruginosa
NOT commensal and is aerobic and oxidase positive. Nosocomial UTI, pneumonia in patients with cystic fibrosis, infections of the skin, eye, and outer ear, common in hot tubs
Enterohemorrhagic E. coli (EHEC)
Produces Shiga-like toxin, released upon the cell's lysis, Most outbreaks are due to serotype O157:H7, Cattle are the main reservoir, Causes hemorrhagic colitis and hemolytic uremic syndrome, infects large intestine
Treponema pallidum
STI - Syphilis: spirochete. Disease characterized by sores around the genitalia or at original site of infection. Divided into primary, secondary, and tertiary syphilis
Ureaplasma urealyticum in genitourinary tract
STI - causes 20% of non-gonococcal urethritis
Mycoplasma hominis in genitourinary tract
STI - urethritis, infrequent cause of pelvic inflammatory disease
Shigella
Shigellosis (bacillary dysentery) symptoms similar to EIEC from E. Coli - cellular invasion via endocytosis allows bacteria to enter bloodstream and infect other endothelial cells. Low ID50 (<100)
Borrellia burgdorferi
Spirochete that causes Lyme disease - most common vector borne disease in US. Characterized by erythema chronicum migrans (bullseye rash) and flu like symptoms. Can have progressive CNS response
Pasteurella multocida
Spreading cellulitis wound infection from dog and cat bites
Catalase test differentiates between
Staphylococcus and Streptococcus
Coagulase test differentiates between
Staphylococcus aureus and other staphylococcus bacteria
Clostridium tetani in nervous system
Tetanus (lockjaw) caused by soil infecting wounds, allowing entry of pathogens into blood circulation. Pathogen produces tetanus toxin that affect the nervous system blocking release of inhibitory transmitters, causing irreversible contractile signal, causing muscular spasms
Staphylococcus aureus toxinoses - vagina/nose
Toxic Shock Syndrome Toxin - produced locally and exerts systemic effect via blood stream resulting in super antigens that stimulate T cells to release cytokines leading to rash, shock, and organ failure
Enterococcal faecalis & faecium
UTIs, bacteremia, wound infections, and endocarditis
Listeria fogenes in reproductive tract
abortion in pregnant women
Staphylococcus aureus: pyogenic pathology of skin - furuncle
abscess causing pus filled inflammation of hair follicles which can lead to cellulitis
Mycobacteria
acid fast, aerobic bacilli, cell wall containing mycolic acid, rigid filamentous
Bacillus anthracis of the skin
anthrax: darkening of infected spots on skin surface due to vesicle development - can be transmitted through the air
Mycoplasma pneumoniae in respiratory tract
atypical pneumonia lower respiratory tract infection: bacterial attachment to epithelium leads to inhibition of ciliary motion and necrosis of epithelium. symptoms include headache, fever, and non-productive cough - only infects humans
Listeria fogenes in blood/heart
bacteremia that can lead to endocarditis
Streptococcus pneumoniae, listeria, neisseria meningitides, haemophilus influenzae, escherichia coli
bacteria that cause meningitis
Staphylococcus aureus, streptococcus pyrogenes, streptococcus pneumoniae, streptococcus agalactiae, neisseria meningitides, moraxella catarrhalis, chlamydia pneumoniae, chlamydia psittaci, mycoplasma pneumonia, haemophilus influenzae, legionella pneumonphila, escherichia coli, klebsiella pneumoniae, pseudomonas aerugionsa, francisella tularensis
bacteria that cause pneumonia
Streptococcus pneumoniae of nasopharynx/respiratory tract - pneumococcal pneumonia
capsules and adherence on pathogen inhibit lysis by phagocytes and have different antigen types - complement system NOT active
Streptococcus pyrogenes: toxinoses of skin - scarlet fever
caused by erythrogenic exotoxins - symptoms include red sunburn-like rash on neck, trunk, and extremities
Streptococcus pneumoniae of meninges (brain and spinal cord) - meningitis
causes adherence of pathogen to endothelial cells of the meninges. occurs mostly at ages >30 years and 1-23 months
Bartonella henselae
causes cat-scratch disease and bacillary angiomatosis, Cat-scratch fever is characterized by low fever and lymphadenopathy
Enteroinvasive E. coli (EIEC)
causes diarrhea with pus similar to shigella with inflammatory cells in the stool (dysentery) - in large intestine
Streptococcus agalactiae
causes meningitis, pneumonia, and bacteremia in newborns as they pass through birthing canal. 30% of mothers are Group B strep positive
Staphyloccocus saprophyticus: vagina/ureter/rectum
causes urinary tract infections (UTIs)
Vibrio cholerae
cholera - toxin causes active secretion of ions and water into small intestine by activating adenyl cyclase and increasing cAMP - leads to shock, electrolyte loss, and dysentery. High ID50 (10^6)
Staphylococcus aureus: pyogenic pathology of lung/respiratory tract - necrotizing pneumonia
complicated form of pneumonia that occurs due to development of necrosis within lung tissue
Streptococcus pyrogenes: toxinoses of skin - necrotizing fasciitis (flesh-eating bacteria)
death of soft tissues that spreads rapidly and mostly affects the limbs
Clostridium perfringens in connective tissue - virulence factors
degradative enzymes facilitate spread and liquefy tissue while the alpha toxin kills cells and increase capillary permeability
Streptococcus mutans in teeth
dental cavaties
Streptococcus bovis of the heart
endocarditis
Streptococcus mutans in blood/heart
endocarditis and bacteremia which enters bloodstream during dental procedures
Staphylococcus aureus toxinoses - skin
exofoliatin - causes scalded skin syndrome characterized by skin blistering and epidermolysis (separation of epidermis)
Gram-negative rods of enteric tract (Enterobacteriaceae)
facultative anaerobes that primarily live in the colon and possess both endotoxins and exotoxins
Listeria fogenes in GI tract
food poisoning - can grow at 4 degrees celsius. large outbreaks occurred due to contaminated processed foods
Salmonella enterica
food poisoning - major cause from poultry, eggs, and pork. Gastroenteritis is a localized disease caused by penetration of mucosal cells by bacteria. Symptoms are nausea, diarrhea, and vomiting. Invades epithelial cells of the small intestine with 1500 serotypes
Bacillus cereus of the GI tract
food poisoning: emetic form is heat stable enterotoxin found in warmed rice while diarrheal form is found in meats and veggies and is heat labile
Clostridium perfringens in GI tract - food poisoning
found in meat and gravy and can grow in reheated foods. Enterotoxin produced in small intestines after sporulation that is heat resistant. Low mortality. Symptoms include diarrhea and cramps 8-20 hours after ingestion
Vibrio parahaemolyticus
gastroenteritis from raw seafood; symptoms similar to cholera
Chlamydia trachomatis in the birth canal/vagina/rectum/penis - urethritis/prostatitis/proctitis
in men. symptoms include clear, watery discharge from the penis
Chlamydia trachomatis in the birth canal/vagina/rectum/penis - cervicitis/salpingitis
in women is a major cause of infertility
Clostridium perfringens in connective tissue - gas gangrene
infection of severe and open wounds that can spread through spores and invade muscle and other tissues. symptoms include blackened, swollen skin or tissue
Staphylococcus aureus: pyogenic pathology of bone/joint: osteomyelitis
infection of the bone that can spread to blood tissue; dead bone
Streptococcus pyrogenes: pyogenic pathology of skin - cellulitis
infection of the deeper tissues
Staphylococcus aureus: pyogenic pathology of heart - endocarditis
infections of inner lining of the heart (endocardium) due to spread of pathogen in the blood
Mycoplasma
lack cell wall, cholesterol bilayer, pleomorphic, unusual self-replication, very small genome, strict dependence on host
Mycobacterium leprae
leprosy (Hansen's disease) - rare in US, slow growing, contracted by prolonged skin contact, can cause nerve damage and limb deformities
Staphylococcus aureus: pyogenic pathology of skin - mastitis
localized infection of lobules of breast tissue that results in swelling, redness, and warmth
Staphylococcus aureus: pyogenic pathology of skin - boils
lots of pus, can cause pain, walled off infection
Listeria fogenes in brain/spinal cord
meningitis: major cause in newborns, elderly, or immunocompromised patients with high mortality rate
Streptococcus pneumoniae of nasopharynx/respiratory tract - ear (otitis media)
most common cause of ear infections in children and is multifactorial
Clostridium perfringens in connective tissue - myonecrosis
necrosis (cell death) of muscle tissues caused by pathogen invasion
Staphyloccocus saprophyticus: coagulase test
negative
Staphylococcus epidermidis: coagulase test
negative
group B strep, E. coli, listeria monocytogenes, strep pneumoniae
neonatal or elderly meningitis
Listeria
no anaerobic growth, no spore formation, no exotoxins
Corynebacterium
no anaerobic growth, no spore formation, yes exotoxins
Bacillis
no anaerobic growth, yes spore formation, yes exotoxins
Neisseria gonorrhoeae in genitourinary tract/oral cavity/rectum - gonorrhea
no capsule - pyogenic STI that causes urethritis, pharyngitis, cervicitis, proctitis, conjunctivitis and can lead to pelvic inflammatory disease. Majority of women are asymptomatic.
Neisseria gonorrhoeae in genitourinary tract/oral cavity/rectum - acute salpingitis
no capsule - vaginal and cervical infection; atopic pregnancy
Streptococcus pneumoniae: group type
none (does not possess group antigens)
Streptococcus pyrogenes: immune-related (post-infection) of blood/vascular system - rheumatic fever
occurs when anti-M antibodies cross-react with heart and joint tissues causing fever, rash, carditis, and arthritis
Streptococcus pyrogenes: immune-related (post infection) of blood/vascular system - glomerulonephritis
occurs when antigen-antibody complexes accumulate on the glomerular of the kidneys causing hypertension, edema of the face and ankles, and bloody urine (Type III hypersensitivity)
Streptococcus pyrogenes: pyogenic pathology of lungs
pneumonia
Chlamydia psittaci in respiratory tract
pneumonia (parrot fever)
Acinetobacter in respiratory tract
pneumonia, sepsis, and urinary tract infections, mostly affects immunocompromised patients and is found in water
Staphylococcus aureus: coagulase test
positive
Streptococcus pyrogenes: toxinoses of skin - strep toxic shock syndrome
produced locally and exerts systemic effect via blood stream resulting in super antigens that stimulate T cells to release cytokines leading to rash, shock, and organ failure
Chlamydia
rigid cell wall
Staphylococcus aureus toxinoses - GI tract
secretion of a heat-labile enterotoxin that causes food poisoning. symptoms include diarrhea and vomiting
Streptococcus pyrogenes: pyogenic pathology of skin - erysipelas
skin inflammation caused by degradative enzymes such as nucleases and hemolysins
Staphylococcus aureus: pyogenic pathology of soft tissues - abscess
soft tissue abscess in the muscle tissue or eye
Staphylococcus aureus: pyogenic pathology of skin - impetigo
sore spots surrounding red skin which can be caused by wound infections
Streptococcus pyrogenes: pyogenic pathology of skin - impetigo
sore spots surrounding red skin which can be caused by wound infections
Streptococcus pyrogenes: pyogenic pathology of throat - pharyngitis
strep throat characterized by sore and red spots on the throat
Chlamydia pneumoniae
transmitted by respiratory secretion - atypical pneumonia or bronchitis. causes 10% of pneumonias and by age 20, 50% have antibodies
Enterotoxigenic E. coli (ETEC)
traveler's diarrhea, watery diarrhea, low-grade fever, nausea, and vomiting. infects small intestine
Mycobacterium tuberculosis in respiratory tract/blood
tuberculosis - white plague or consumption. severe cases can cause death by years of coughing, fever, and weight loss
Streptococcus mutans: group type
viridans
Mycobacterium avium-intracellulare in respiratory tract
virulent form of tuberculosis infection occurs commonly in severely immunosuppressed patients - most common systemic bacterial infection
