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What is the most common cause of ascending UTIs?
E. coli
associated with urinary stones
Proteus mirabilis
organism produces urease, which acts on urea to produce ammonia
Proteus mirabilis
causes UTIs in young sexually active women
Staph. saprophyticus
associated with UTI in hospitalized patients
Staph. epidermis, Enterococcus
T or F - viral causes of UTIs are rare
T
virus establishes latency in epithelial cells in kidney tubules and ureter after entering respiratory tract
human polyomaviruses
implicated as cause of hemorrhagic cystitis
adenovirus
virus infects capillary blood vessels in kidney and can cause renal syndrome
hantavirus
Fungi that can cause UTIs
Candida, Histoplasma capsulatum
Protozoan causes urethritis in males and vaginitis in females
Trichomonas vaginalis
Infections with this parasite results in inflammation of the bladder
Schistosoma haematobium
Mechanical factors that predispose to UTI
1. shorter female urethra
2. sexual intercourse
3. uncircumcised male
Obstructions to complete bladder emptying (5)
1. residual urine >2-3ml
2. loss of neruologic control
3. vesicoureteral reflux
4. diabetes mellitus
5. catheterization
Where do most urinary tract pathogens originate?
fecal flora
Which species can actually colonize and infect urinary tract?
aerobic, facultative (E.coli)
a product of E. coli that is linked with the capacity to cause kidney damage
hemolysin
normal pH of urethra
4.6-8
3 factors that enable healthy urinary tract to be resistant to bacterial colonization
1. pH
2. chemical content
3. flushing mechanism
Clinical features of acute lower UTI
1. dysuria
2. urgency
3. frequency
Appearance of urine in acute lower UTI
cloudy due to pyuria, bacteria, may contain blood
people lacking antibacterial substances normally found in prostatic fluid may be susceptible to this
acute bacterial prostatis
Infection of kidney complicated by lower UTI symptoms, fever, and pain in kidney
pyelonephritis
common cause of upper UTI
Staphylococci
Complications of repeated upper UTIs
loss of function of renal tissue, hypertension
Quantitative definition of bacteriuria
over 10^5 organisms/ml (only one bacterial species)
treatment of UTIs
antibacterial agents
(ex: augmentin)
Prevention of UTI
1. regularly emptying bladder
2. prophylactic use of antibio
3. good catheter care
Host factors that increase risk of STD
1. genital lesions/ulcers
2. uncircumcised men
3. multiple infection
Causes syphilis
Treponema pallidum
3rd most common STD
syphilis
T or F - Treponema pallidum is sensitive to drying, heating, and disinfectants
T
Characterizes intial contact stage of syphilis
primary painless chancre
Characterizes primary syphilis
enlarged inguinal nodes followed by spontaneous healing
Why are inguinal nodes enlarged during primary syphilis?
proliferation of treponemes in lymph nodes
Characterizes secondary syphilis
flu-like illness, mucocutaneous rash, headache, fever
What is the pathogenesis during secondary syphilis?
multiplication and production of lesions in lymph node, liver, joints, muscles, skin, mucous membranes
Pathogenesis in latent syphilis
treponemes dormant in possibly the liver and spleen
(covered with lipids)
Characterizes tertiary syphilis
neurosyphilis, cardiosyphilis, progressive destructive disease
Pathogenesis in tertiary syphilis
re-awakening and multiplication of treponemes, dissemination and invasion
3 results of congenital syphilis
1. infection resulting in intrauterine death
2. congenital abnormalities
3. silent infection - appear at 2
treatment of syphilis
penicillin, tetracycline, doxycycline, erythromycin
Causes gonorrhea
Neisseria gonorrheae
Reservoir/transmission of gonorrhea
humans/sexual contact
T or F - Neisseria gonorrheae is sensitive to drying
T
Who forms the major reservoir of infection by N. gonorrheae?
asymptomatic women
4 mechanisms gonococcus uses to attach to mucosal surfaces
1. fimbriae for attachment
2. LPS - endotoxin activity
3. IgA protease
4. capsule resists phagocytosis
What type of cells do gonococci invade?
non-ciliated epithelial
What actually causes damage in gonorrhea?
inflammatory responses elicited by organism
Symptoms of gonorrhea in the male
urethral discharge, pain on urination
Symptoms of gonorrhea in women
vaginal discharge
Complications of gonorrhea in asymptomatic women
1. PID
2. chronic pelvic pain
3. infertility - damaged fallopian tubes
Type of gonorrheal infection in infants
ophthalmia neonatorum
Is penicillin recommended for treatment of gonorrhea?
no
Treatment of gonorrhea
ceftriazone, ciprofloxacin, spectinomycin
Causes chlamydial infection
chlamydia trachomatis
Form of C. trachomatis adapted for extracellular survival
elementary body
Form of C. trachomatis adapted for intracellular survival
reticulate body
Cycle of C. trachomatis
enters host through mucosal surface, binds and enters cell through endocytosis, fusion of vesicles with lysosomes is inhibited - EB differentiates into metabolically active RB, which divide and produce EB
Pathogenesis of C. trachomatis in men
urethritis, epididymitis, proctitis, conjuctivitis
Pathogenesis of C. trachomatis in women
urethritis, cervicitis, salpingitis, conjuctivitis
Treatment of chlamydia
doxycycline, tetracycline

babies - erythromycin
Causes of inguinal lymphadenopahty
genital infections
Causes lymphogranuloma venereum
Chlamydiae trachomatis
Treatment of lymphogranuloma venereum
tetracycline, doxycycline
Causes chancroid
Haemophilus ducreyi
Characterizes chancroid
painful genital ulcer, local lymphadenitis
Most common form of genital ulcers in Africa and Asia
chancroid
Treatment of chancroid
erythromycin, caftraixone, otrimoxazole
Causes donovanosis
Calymmatobacterium granulomatis
Characterizes donovanosis
genital nodules, which form granulomatous ulcers that bleed on contact
Regions where donovanosis is found
Caribbean, New Guinea, India, central Australia
Treatment of donovanosis
tetracycline
Found colonizing genital tracts of healthy sexually active men and women
Mycoplasma hominis, Ureaplasma urealyticum
Associated with PID and postabortal and postpartum fevers
Mycoplasma hominis, Ureaplasma urealyticum
Treatment of Mycoplasmas and Non-gonococcal urethritis
tetracycline
Normal inhabitant of female genital tract
Candida albicans
Symptoms of candida infection
irritant vaginitis with cheesy vaginal discharge
Treatment of Candida infections
oral antifungals (fluconazole), nystatin
Causes trichomonas infection
Trichomonas vaginalis
Transmission of trichomonas
sexual intercourse, bedding, clothing, toilets
Symptoms of trichomonas in women
vaginitis with copious foul-smelling discharge, increase in pH
Treatment of trichomonas infection
metronidazole
Causes bacterial vaginosis
Gardnerella vaginalis, Bacteroides
Symptoms of bacterial vaginosis
1. excessive malodorous vaginal discharge
2. vaginal pH >4.5
3. clue cells
4. fishy odor
What is pathogenicity of bacterial vaginalis related to?
disrupting normal acidity of vagina
What is the genital strain of HSV?
HSV2
What are symptoms of genital herpes?
vesicles that break and form shallow ulcers, local lymph nodes swollen, fever, headache, malaise
Where is the latent infection of genital herpes?
dorsal root ganglion neurons
Does condom use prevent genital herpes?
no
Treatment of genital herpes
topical acyclovir
What causes genital warts?
papillomavirus 6,11,12,16,18,31
Incubation period of genital warts
1-6 months
Treatment of genital warts
podophyllin
Which strains of papillomavirus are associated with cervical cancer?
16,18
Which genes normally suppress cell division (tumor-suppressor genes)?
p53, pRb
Describe papillomavirus
double-stranded, not enveloped
How does papillomavirus infect host?
viral DNA integrated into host chromosome and expresses E6,E7
E6 binds to p53, E7 binds to pRb
What affect does E6 binding to p53 have?
cell continuously divides and enters mitosis
What affect does E7 binding to pRb have?
e2f binds to promoter and genes are transcribed
Infection of which cells is the major source of transmitted HIV virus?
peripheral blood mononuclear cells
What causes decrease in CD4 and MHC1 expression in HIV?
nef
Describe ARC (AIDS related complex)
weight loss, fever, persistent lymphadenopathy, oral candidiasis, diarrhea
What is the value that is considered AIDS?
200 CD4/ml
What lab tests are run to diagnose HIV?
ELISA, followed by Western blotting, oral swab (gp24)
What could be a problem with an HIV vaccine?
induced antibodies against gp120 may combine with virus, attach to monocytes, and be ingested - infection
Treatment of HIV
AZT (nucleoside analog of rt)w/ protease inhibitors
neviropine (non-nucleoside analog)
ritonavir (protease inhibitor)
What is the best therapy for HIV?
HAART - highly active antiretroviral therapy
What arthropod commonly attaches to pubic hair and causes infestation?
Phthirus pubis
Treatment of pubic or crab louse
malathion
What causes genital scabies?
Sarcoptes scabei
Treatment of genital scabies
10% benzyl benzoate, 1% benzene hexachloride
How is mumps spread?
airborne droplets, salivary secretions, possibly urine
Where does the mumps virus settle?
parotid gland
What other organs can mumps infect?
thyroid, pancrease, epididymus
What type of vaccine is MMR?
live attenuated
What are the effects of congenital mumps?
deafness, mental retardation, cataracts
What is the largest human herpesvirus?
cytomegalovirus
How is CMV transmitted?
saliva
How does CMV spread?
upper respiratory tract, lymphoid tissue, circulating monocytes and lymphocytes, salivary glands and kidney tubules, cervix, epididymus, testes
What is the most common viral cause of congenital defects in US and what are the symptoms?
CMV, microcephaly, mental retardation, hearing loss, jaundice
What does CMV cause in immunodeficient patients?
interstitial pneumonia
Treatment of CMV
ganciclovir
How is EBV transmitted?
exchange of saliva
Where does EBV replicate?
B lymphocytes binding to cd3 receptor
What are symptoms of EBV due to?
action of cytokines released
What are the major symptoms of EBV?
sore throat, lymphadenopathy, splenomegaly, lethargy
Treatment of EBV
high does of acyclovir
How has EBV been related to cancer?
absence of T cell immunity results in polyclonal leukemia-like B cell proliferation
What disease are EBV and malaria closley associated with?
Burkitt's lymphoma
How is malaria a co-carcinogen of EBV?
it weakens T cell control of the EBV infection
Which oncogene is related to Burkitt's lymphoma?
c-myc
How was global smallpox eradicated?
widespread vaccination using attenuated strain of virus
When was smallpox completely eradicated?
1980
What are arboraviruses?
arthropod-borne viruses
In arboraviruses, where does the virus multiply?
salivary gland
What transmits yellow fever?
mosquito Aedes aegypti
What is the reservoir of yellow fever?
humans
Treatment of yellow fever
live attenuated vaccine, insect repellent
What is the vector of dengue fever?
mosquito A. aegypti
What is a particularly severe form of dengue fever?
dengue hemorrhagic fever syndrome
Where does dengue fever virus replicate?
monocytes, vascular endothelium
Treatment of dengue fever
no antiviral therapy or vaccine
To which parts of the world is Burkitt's lymphoma restricted?
Africa, Papau New Guinea
To which parts of the world is yellow fever restricted?
Africa, Central/South Am., Caribbean
To which part of the world is dengue fever restricted?
S.E. Asia, Pacific, India, Caribbean
What is break bone fever?
dengue fever
What are rickettsia?
small bacteria, which are obligate parasites
What are typical symptoms of rickettsial infections, and where does it multiply?
fever, headache, rash; skin, CNS, liver
What is caused by R. rickettsii?
Rocky mountain spotted fever
What carries R. rickettsii?
dog and wood ticks
Treatment of rocky mountain spotted fever
tetracycline i.v.
Caused by R. conorri, carried by dog ticks
Mediterranean spotted fever
What transmits epidemic typhus?
louse Pediculus corporis
What causes epidemic typhus?
R. prowazeckii
What is associated with poverty and war?
epidemic typhus
Symptoms of epidemic typhus
fever, headache, flu-like, maculopapular rash, severe meningoencephalitis with delirium and coma
What causes and transmits endemic typhus?
R. typhi, rat flea
What causes and transmits Lyme disease?
Borrelia, hard ticks (Ixodes)
What is the leading vector-borne disease in US?
Lyme disease
What is the lesion characteristic of lyme disease?
erythema chronicum migrans
Additional disease caused by lyme disease
neurologic, cardiologic, arthritis
Treatment of lyme disease
penicillin, tetracycline
What is the most virulent species that causes malaria?
P. falciparum
What is the vector for malaria?
female anopheles mosquito
Which part of the life cycle of plasmodium is in the mosquito's saliva?
sporozoites
Where do the sporozoites mature into merozoites?
liver
What are hypnozoites?
merozoites that remain in the liver and lie dormant
Where do merozoites multiply?
red blood cells
What is the stage of plasmodium during the sexual cycle?
gamaetocytes
When is the sexual cycle of Plasmodium complete?
Anopheles mosquito feeds on gamaetocyte containing blood, forms zygote, releases sporozoites
Most characteristic feature of malaria
synchronous cycle times of fever (rupture of merozoites)
What are complications of malaria that make it fatal?
cerebral malaria, severe anemia, hypoglycemia, lactic acidosis
Treatment of malaria
chloroquinine
Causes African trypanosomiasis
Trypanosoma brucei gambiense and T. rhodesiense
Vector of trypanosomiasis
tse-tse fly
Symptoms of trypanosomiasis
swollen chancre, swollen lymph nodes, CNS, coma
Treatment of trypanosomiasis
arsenical drugs (tryparsamide, melarsoprol), non-arsenical drugs (suramin, nitrofurazone, pentamidine)
Causes chaga's disease
T. cruzi
Transmission of chaga's disease
reduviid bug
Major cause of death in chaga's disease
myocarditis
Treatment of chaga's disease
arsenicals
Transmission of leishmaniasis
sandflies
Visceral leishmaniasis; where does it grow
L.Donovani; liver, spleen
Cutaneous leishmaniasis
L. Tropica
Where does leishmaniasis inhabit?
macrophages
What is the form of leishmaniasis that results in liver failure?
kal-azar
Treatment of leishmaniasis
antimonial compounds
What leads to pathology of disease in schistosomiasis, and what effect is on the body?
egg production, hypersensitivity to antigens released by eggs
Treatment of schistosomiasis
praziquantel removes worms, but pathology irreversible in advanced cases
Causes lymphatic filariasis
Brugia, Wuchereria
Transmission of filariasis
mosquito
Introduction to body of schistosomiasis
through skin
Intro. to body of filariasis
through skin
Locations of filarial worms
lymph nodes, lymphatics of limbs and groin
Which parasite leads to obstruction of lymphatics and gross enlargement of breasts, scrotum, and limbs?
filarial nematodes
Treatment of filariasis
diethylcarbamazine (larvae), suramin (adults)
Arenavirus that infects bush rats of West Africa
lassa fever virus
What is the most commone febrile illness in Sierra Leone?
lassa fever virus
How is lassa fever virus acquired?
human exposure to infected rats or their urine
What virus is associated with Korean Hemorrhagic fever?
Hantaan virus
How has Korean Hemorrhagic fever presented in US?
pulmonary disease
What type of virus causes Marburg and Ebola Hemorrhagic fevers?
filovirus
Symptoms of Marburg and Ebola Hemorrhagic fever
fever, hemorrhage, rash, disseminated intravascular coagulation
Infection of this virus first noticed after exposure to African green monkeys from Uganda
Marburg virus
Location of Ebola
Southern Sudan
Causes Q fever
rickettsia - Coxiella burnetii
How is Coxiella burnetii different from other rickettsia?
1. not transmitted by arthropods
2. transmission by inhalation
3. main action in lungs, not endothelium
How are humans infected with Q fever?
placenta of infected animal, unpasteurized milk, tissue fluids
T or F - Q fever can become chronic
T
Treatment of Q fever
tetracycline, erythromycin
What causes anthrax?
Bacillus anthracis
What are two ways to contract anthrax?
1. spores
2. infected herbivore
Describe cutaneous anthrax
spores germinate at site of entry, producing anthrax toxin, consisting of edema factor
-center becomes black and necrotic (eschar)
What is released from bacilli in pulmonary anthrax?
lethal toxin
Treatment of anthrax
penicillin
vaccine of purified protective antigens
What causes the plague?
Yersinia pestis
What is the reservoir of the plague?
rodents
What is the vector of the plague?
rat flea
Is bubonic plague transmitted from person to person?
not generally
How can the plague spread from person to person?
droplets causing pneumonic plague
Sign of plague
lymph nodes in armpit and groin become tender and form buboes with hemorrhagic inflammation
Treatment of plague
streptomycin, tetracycline
vaccine of formalin-killed bacteria
What causes tularemia?
Franchisella tularensis
How is tularemia spread?
arthropod vectors
Can tularemia spread from person to person?
no
Describe symptoms of tularemia
febrile illness, lymphatic spread, lungs, GI tract, liver
Treatment of tularemia
streptomycin
live attenuated vaccine
What are leptospira?
tightly coiled spirochetes
How are humans infected with Leptospirosis?
ingestion of contaminated food, water; aquired by swimming
Treatment of leptospira
penicillin, tetracyclines
Which species of Brucellae infects cows?
B. abortus
Which species of Brucellae infects goats and sheep?
B. melitensis
Which species of Brucellae infects pigs?
B. suis
Where are Brucellae bacteria present?
feces, urine, milk of animals
What are symptoms of Brucellosis?
fever, drenching sweat, aching, weakness, enlarged lymph nodes, spleen
Describe the chronic stage of Brucellosis
tiredness, aches, pains, anxiety, depression
Where does the adult echinococcus live?
intestine of dog
Where do circulating larvae lodge in echinococcus?
liver
What are the cysts called formed by echinococcus?
hydatid cysts
Treatment of echinococcus
praziquantel, surgical removal
What causes trichinella?
T. spiralis
How are humans infected with T spiralis?
eating undercooked meat
Where does T. spiralis mature?
striated muscle
Symptoms of trichinella
fever, joint and muscle pain, hemorrhage, encephalitis, cardiac abnormalities
Treatment of trichinella
antihelmintics (thiabendazole)

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