Intro to Bacteria Part 3 Flashcards
H. influenzae growth medium
blood containing medium
H. influenzae virulence factor
polysaccharide capsule
H. influenzae in children
causes meningitis, epiglottitis, septic arthritis
H. influenzae meningitis presentation
children present with fever, vomiting, altered mental status
H. influenzae epiglottitis presentation
child presents with history of sore throat and fever, then develops stridor and is unable to swallow, may be excessively drooling
H. influenzae septic arthritis presentation
infants present with fever, pain, swelling, and decreased ROM in joint
H. influenzae sepsis presentation
Children between 6 months and 3 years present with fever, lethargy, loss of appetite, no evidence of localized disease
H. influenzae B vaccination
very difficult to stimulate an immune response in young children, cells are taught to fight against b capsule antigens with a variety of other vectors
H. ducreyi associated disease and presentation
STI, chancroid; pt presents with painful genital ulcer, painful inguinal LN which may become matted and rupture
H. ducreyi differential diagnoses
syphilis (but chancre is painless); herpes (accomp by fever and myalgias); Lymphogranula venerum (painless LN)
Gardnerella vaginalis disease and presentation
vaginitis with anaerobic vaginal bacteria; women present with burning or itching of labia, dysuria, copious, foul smelling vaginal discharge
Clue cells
vaginal epithelial cells that contain pleomorphic bacilli in cytoplasm
B. pertussis disease association
whooping cough
B. pertussis virulence factors
pertussis toxin, extra cytoplasmic adenylate cyclase, filamentous hemagglutinin, tracheal cytotoxin
Pertussis toxin
A and B subunits, causes histamine sensitization, increase in insulin synthesis, promotion of lymphocyte production and inhibition of phagocytosis; ultimately increase cAMP
Extra cytoplasmic adenylate cyclase in B. pertussis
cAMP production results in impaired chemotaxis and generation of H2O2 and superoxide
Filamentous hemagglutinin in B. pertussis
pili that assists in binding to epithelial cells
Tracheal cytotoxin in B. pertussis
destroys ciliated epithelial cells; impaired clearance of bacteria, mucus, inflammatory exudate
Legionella pneumohpila characteristics
aerobic G- rod, contaminated water sources; facultative intracellular parasite, survives in a biofilm
Pontiac fever
HA, muscle aches, fatigue, fever, chills
Legionnaires’ disease
pts develop high fevers and severe pneumonia, HA, confusion, myalgias, cough, elevated liver enzymes, hyponatremia
Y. pestis disease association
bubonic plague carried by rats and fleas
Y. pestis F1
capsular antigen with antiphagocytic properties
Y. pestis V and W antigens
actions unknown
Y. pestis characteristics
G- with bipolar staining pattern
Y. pestis presentation
nodes are hot, red, painful, fever, HA, hemorrhages under skin lead to black discoloration; pt may be hiking in AZ or NM
Francisella rularenis disease association
Tularemia, infects rabbits, ticks, deerflies
Ulceroglandular tularemia
F. rularenis; hole in skin with black base, fever, swollen LN, skin ulcer differs from plague
Pneumonic tularemia
aerosolized bacteria infects lungs leading to pneumonia
Brucella transmission
contact with infected animal meat or aborted placentas
Brucella transmission
Meat-packing worker, vet, farmer, traveler presents with fever, chills, sweat, loss of appetite, backache, ha, lymphadenopathy, undulant fever
Pasturella multocida
G- zoonotic organism, colonizes mouths of cats; pt will present with cat bite or scratch
Chlamydia infections
conjunctivitis, cervicitis, pneumonia
Chlamydia elementary body
metabolically inert
Chlamydia initial body
enveloped in a cell, produces it’s own DNA/RNA/protein, but relies on the cell for ATP
Chlamydia life cycle
EB enters columnar epithelial cells, transforms into an IB(or multiple IBs)
Chlamydia trachomatis
infects eyes and genitals, chronic conjunctivitis
Inclusion conjunctivitis
C. trachomatis, conjunctival inflammation with purulent yellow discharge and swelling of eyelids
Infant pneumonia with C. trachomatis
infant in first 4-11 weeks of life, UR sxs, rapid breathing, cough, and resp distress
Urethritis with C. trachomatis
nongonococcal urethritis; usually asymptomatic but may develop dysuria, mucoid discharge
Cervicitis and PID, C. trichomatis
red, swollen, yellow mucopurulent discharge from cervix, can spread upward to cause PID
PID presentation
abnormal vaginal discharge or bleeding, dyspareunia, nausea, vomiting, fever, lower abd pain, “chandelier sign”
may cause infertility, tubal pregnancy, chronic pelvic pain
Epididymitis, C. trichomatis
urethritis, unilateral scrotal swelling, tenderness, pain, fever
Reiter’s syndrome
arthritis of large joints in men between 20 and 40, inflammation of eyes and urethritis; C. trichomatis
Fitz-Hugh-Curtis syndrome
infection of liver capsule with symptoms of RUQ pain in men and women; C. trichomatis
Lymphogranuloma Venerum
STI caused by C. trachomatis, painless ulceration or papule that may heal spontaneously, followed by LN enlargement
Chlamydophila psittaci
common in birds, will cause atypical pneumonia called psittacosis
Atypical pneumonia presentation
dry cough, fever, less “sick-looking,” less well-defined infiltrates
Chlamydophila pneumoniae
Taiwan and Acute Respiratory, atypical pneumonia in young adults
Rickettsia characteristics
small, G-, non-motile, obligate intracellular energy parasites
How does Rickettsia differ from Chlamydia?
requires an arthropod, replicates in cytoplasm, tropism for endothelial cells, causes rashes, fevers, headaches, conjunctivitis
Weil-Felix reaction
test for Rickettsia, cross-reactivity between Proteus vulgaris and Rickettsia
Rickettsia rickettsii
Rocky mountain spotted fever, caused by tick; fever, conjunctival redness, severe HA, rash that starts on limbs and moves toward trunk
Rickettsia akari
rickettsialpox, mites on mice; mild, febrile dz with a small bump that turns into a blister, HA may develop along with other vesicles over the body
Rickettsia prowazekii
Epidemic typhus, often transmitted by lice; fever and HA, small pink macules on trunk that spare limbs, blood vessel clotting
Brill-Zinsser Disease
latent Rickettsia prowazekii, no skin rash and milder symptoms
Rickettsia typhi
endemic or murine typhus, rodents and fleas responsible for transmission; 10 day incubation period followed by fever, HA, rash
Rickettsia tsutsugamushi
Asia and south pacific, transmission via rodents and chiggers; high fever, HA, scab at bite site
Rickettsia parkeri
fever, HA, eschars, regional lymphadenopathy
Rickettsia africae
African tick-bite, unexplained fever
Bartonella quintana
louse-borne febrile dz; not an obligate intracellular organism; fevers, HA, rash, severe back and leg pains
Bartionella henselae
Cat-scratch disease, regional LN enlarge, low-grade fever and malaise; bacteremia, endocarditis, bacillary angiomatosis
Coxiella burnetti
Q fever, has an endospore form which can contaminate milk and are aerosolized; pneumonia, NO RASH, fever and soaking sweats
Erlichia chaffeensis
tick-borne dz similar to Rocky Mountain spotted fever but does not cause a rash
Spirochetes characteristics
slender, tightly coiled, G- bacteria
Unique characteristics of spirochetes
surrounded by phospholipid rich outer membranes, periplasmic flagella, very difficult to culture, other methods needed to identify
Disease manifestations of treponema are caused by what?
host’s immune responses
Treponema pallidum
STI, syphilis; most often occurs in MSM or other high-risk sexual behavior; penetrates mucous membranes or invased via abrasias
Primary syphilis
painless chancre that erupts 3-6 weeks after contact, non-tender lymphoid swelling; “firm, ulcerated painless lesion”
Secondary syphilis
bacteremic stage occurs 6 weeks after chancre has healed, widespread rash and generalized lymphadenopathy, condyloma latum (wartlike lesion that can ulcerate)
Latent syphilis
secondary syphilis has resolved, asymptomatic but some may relapse
Tertiary syphilis
can develop over 6-40 years, inflammatory damage
Gummatous syphilis
localized granulomatous lesions which necrose and become fibrotic (skin and bone), painful
Cardiovascular syphilis
aneurysm in aortic arch and destruction of vasa vorum leading to destruction of media layer of aorta (cannot be reversed with antibiotics)
Neurosyphilis
asymptomatic, subacute meningitis, meningovascular syphilis, tabes dorsalis, general paresis (mental deterioration)
Argyll-Robertson pupil
constricts during accommodation but does not react to light, midbrain lesion
Syphilis Rule of Sixes
6 axial filaments, 6 week incubation, 6 weeks for ulcer to heal, 6 weeks later secondary syphilis develops, 6 weeks for secondary to resolve, 66% don’t develop tertiary, 6 years to develop tertiary
Congenital syphilis
occurs when mother contracts syphilis during pregnancy which then crosses the placenta
Early congenital syphilis
wide spread rash, condyloma latum, runny nose, LN, liver, spleen enlargements, bone infection
Late congenital syphilis
neurosyphilis, CNVIII deficit, periosteal inflammation, saddle nose, saber shins, tooth deformities, eye disease
Diagnosing syphilis
Primary or secondary diagnosed with microscopic examination of specimen from chancre; nonspecific treponemal tests (abs to cardiolipin and lecithin); specific treponemal test (specific abs for treponema)
Jarisch-Herxheimer phenomenon
worsening of symptoms after abx start; mild fever, chills malaise, HA, muscle aches
Treponema pallidum subspecies Endemicum
desert zones of Africa and Middle East, spread by sharing drinking and eating utensils, oral mucosa lesions
Treponema pallidum subspecies pertenue
Yaws, disease of tropics spread via mouth ulcers, disfiguring lesions
Treponema pallidum subspecies carateum
limited to rural Latin America, red and blue colored lesions over body
Borrelia
observed under light microscopy, known to cause relapsing fever and Lyme
Borrelia burgdorferi
tick-borne illness, painful lesion at point of inoculation
Early localized stage Lyme
10 days after bite, erythema chronicum migrans
Early disseminated stage Lyme
dissemination to skin, nervous system, heart, joints; more lesions, meningitis, cranial nerve palsies, peripheral neuropathy, migratory joint pain
Late stage Lyme
chronic arthritis, encephalopathy
Borrelia recurrentis
relapsing fever, transmitted via lice; high fever, chills, HA, drenching sweats, may relapse after 8 days
Leptospira
aerobic spirochetes wound up in a tight coil, found in contaminated urine
leptospiremic phase
first phase of leptospira infection, bacteria invade blood and CSF; high fever, HA, malaise, stiff muscles, red conjunctiva, photophobia
Immune phase leptospira infection
IgM ab appearance, may develop meningismus
Weil’s disease
infectious jaundice caused by leptospira interrogans, subbroup icterohemorrhagiae; renal failure, hepatitis with jaundice, mental status changes
Mycobacterium characteristics
thin, beaded rods with lipid laden cell walls that only infect humans; acid-fast
Mycobacterium tuberculosis
increasingly common in HIV/AIDS pts, commonly will colonize lungs
Mycosides
lipid only found in acid-fast bacteria
Mycolic acid
large fatty acid
Mycoside
mycolic acid bound to carb
Cord factor
mycoside formed by union of mycolic acids with disaccharide; inhibits neutrophil migration and damages mitochondria
Sulfatides
cord factor with sulfates attached to disaccaride, inhibit phagosome fusing with lysosome
Wax D
mycoside that enhances antibody formation
M. tuberculosis as a facultative intracellular organism
triggers an infiltriation of neutrophils and macrophages, will live in the macrophages
Cell-mediated immunity in TB
T cells and macrophages kill Mycobacterium and may cause local destruction and necrosis, granuloma formation
asymptomatic primary TB
caseous granuloma formation and scarring, tubercles are often too small to be seen
symptomatic primary TB
children, elderly, immunocompromised; enlarged mediastinal or hilar LN, lower and middle lung infiltrates, may form cavitary lesions
Reactivation TB
will occur in any organs seeded in primary infection
Organ systems that can be involved in TB
pulmonary, pleural and pericardial infection, LN infection, kidney, bones, joints, CNS, miliary TB
TB diagnosis
PPD skin test, chest x-ray, sputum acid-fast stain and culture, rapid molecular detection
TB rule of fives
droplet nuclei are 5 micrometers and contain 5 m. tuberculosis bacilli, infected patients have a 5% reactivation risk in first 2 years and 5% lifetime risk, pts with HIV have a “5+5% risk of reactivation per year
Mycobacterium leprae
acid-fast rod that causes leprosy, colonizes in cooler areas of the body
Lepromatous leprosy
severest form because pts cannot mount a cell-mediated response, skin lesions cover whole body
9leonine facies, saddlenose deformity, loss of sensation)
Tuberculoid leprosy
able to mount cell-mediated response, skin damage is milder, unilateral skin and n. involvement
Non-tuberculous mycobacteria
found in soil and water; can be asymptomatic or cause pneumonia
Mycobacterium avium-complex disease presentation
Pt with AIDS presents with unexplained fevers, weight loss, diarrhea, malaise, elevated alkaline phosphatase; presents as upper lung issues in men and lower lung issues in women
Mycoplasma characteristics
tiniest free-living organisms capable of self-replication, no cell wall and are free to contort
Mycoplasma pneumoniae
bronchitis and pneumonia, number one cause in teenagers and adults; fever, sore throat, malaise, dry cough
Stevens-Johnson syndrome
severe skin rxn characterized by erythematous vesicles and bullae over mucocutaneous junctions
Cold agglutinins
IgM abs directed towards “I” antigen on RBC; blood will clump together when it is cold
Complement fixation test
serum mixed with antigens, rise in ab titer
Sputum culture M. pneumoniae
cholesterol and nucleic acid media, takes 2-3 weeks
Mycoplasma DNA probe
label bacteria DNA
Ureaplasma urealyticum
metabolizes urea, causes non-gonoccocal urethritis
