204 terms

Ch 12 13 14 micro

Gastrointestional system
2nd most common site of infection
How does flora prevent infection?
by competing with pathogens
Oral cavity
has most species
has few bacteria because of acid
Helicobcter pylori
gram neg- microaerophillic, spiral shaped- motile w/ flagella- 30-50% is colonized with it.
What burrows into mucosa of stomach to find neutral pH?
H. pylori
small intestine
bacteria get washed out by pancreatic juice and bile- gram + lactobacilli- metabolize compunds that humans cannot.
Enterococcus faecalis
enteric rods and bacteroides
20% of bacteria is
Large intestine
is holding tank for bacteria that help in digestion-slow flow rate-high bacteria colonization-bacteroids & bifidobacteria
Bacteria found in large intestine
enteric rods, strep, clostridia and lactobacilli
dental plaque
inflammation of gums
overpopulation of normal flora and causes cavities
fusobacteria and actinomyces
bleeding of gums and inflammation
acute necrotizing ulcerative gingivitis
painful chewing
risk factors for periodontal disease
smoking, genetic predispotion, pregnancy, puberty, stress, medication, diabetes, poor nutrition
Periodontal disease can lead to?
decay, toothloss and systemic infection
inflammation of stomach and intestine caused by microorganism or ingestion of toxin- stomach flu
gastroenteritis is caused by
contaminated food or water, contact w infected person, unwashed hands, dirty food utensils, and contaminated work space. ingestion of bacterial toxins
most common cause of foodborne illness
bacteria and toxins
How bacterial infections come about
pathogen enters gi tract, adheres and multiplies
bacterial intoxication
toxins produced by bacteria
Helicobacter peptic ulcer
transmitted via food, water, kissing- weightloss, poor appetite, burping, nausea, vomiting- antibiotics, h2 blockers, proton pump, & stomach lining protector drug
salmonella- enterobacteriacae family- faculative anerobe, rod, gram-neg, non sporing-typhoid fever, food born illness- diarrhea, fever, cramps- contaminated or uncooked food.5-7 days
thyphoid fever
caused by salmonella enterrica-serotype typhi-rod, gram neg, flagella-contaminated food or water-high fever 103-104, headache, nausea, pain, diarrhea, cough, constipation.
enteric fever
parathyphoid fever- milder
bacillialy dysentry- in humans and monkeys- gram neg, non sporing, rod shaped- produces shiga toxin- destroys tissue- dysentry- febrile sezures
4 species of shigella
boydii, dysenteriae, flexneri, sonnei(most common)
camplybacter jejuni- C. fetus & C. coli- vibroid or helical- gram neg- motile- microerophilles- raw poultry- raw milk, nonchlorinated water
C. jejuni
leading cause of diarrhea in US
Escherichia spp. gastroenteritis
E. Coli- pathogen or normal synthesizes vitamins
enterotoxic E. coli(ETEC)
diarrhea- produce toxins- fimbrae
enteroinvasive E. coli (EIEC)
dysentry-no toxins- allow adherance to intestinal epithelium and disrupts microvilli
enteropathic E. coli (EPEC)
no toxins- shigells
enteroaggregative E. coli (EAggEC)
ST toxin, UTI- colonizes small intestine
enterohemorrhagic E. coli (EHEC)
produces enterotoxins
yersinia enterocolitica- gram-neg, fac-anaerobic, rod
Listeria monocytogenes, gram +, non sporing rod, fac. anaerobic intracellular-can spread to CNS- spread to circulatory-11-70 days-20-30 % mortality
clostridium botulinum- NEURO TOXIN- Foodborne, infant, wound, and inhalation
Botulism symptoms
blurred vision, dry mouth, dizzy, constipation, respiratory paralysis
Staph intoxication
in flora of nose, staph aureus (no spores), heat resistant, high osmotic resistance, high salt concentration
bacillus intoxication
bacillus cereus- gram +, spore forming, aerobic, produce enterotoxins
diarrheal type of bacillus intoxication
start 4-16 hours- last 12-24 hours
Emetic type of bacillus intoxication
start 30 min -6 hrs-vomiting
vibrio cholerae- watery diarrhea, vomit, leg cramps- gram neg- fac anaerobe- vibroid or rod- chloratoxin and enterotoxin
children- 55,000 hosp. 3-8 days
Astroviruses and calciviruses
+ sense, ssRNA group iv- winter animals, and malaise 5 days
ssRNA nonenveloped-3 days to 2 weeks- contagious
group 1, dsDNA, resp, conj, GI, UTI-type 40 and 41 group f
A & E- HAV- hygene and is common; HEV- RARE
oral candida
candida albicans- flora- illness and medications cause change- antibiotic, birth control and steroids, diabetes, HIV and cancer
mold- Aspergillus flavus- corn and peanuts- produces aflatoxin- causes hepatitus, immunosupression, and helptocellular carcinoma- abcess in GI tract- systemic
fungus- claviceps purpures- produces alkaloids- hallucinations, GI upset, gangrene, st anthonys fire (pain in limbs)
St. Anthonys fire
pain in limbs from ergotism
Giardialamblia or G. intestinalis- greasy stools, flatuence, cramps, nausea- 1-2 weeks after infection, last 2-6 weeks
Balantidium coli
largest protozoan parasite of humans, pigs and monkeys- fecal/oral transmission- watery stools, anorexia, nausea and pain- tetracycline to treat and metronidazole and todoqunol
Entameoba histolytica (Amebiosis)
100k annual mortality- water containing cysts or fecal oral route- no animal reservoir- acute amoebic colitis
cryptosporidium- fecal-oral route- uncooked meat- water- resistant to chlorine (swimming pools)- most common water born in US.
tapeworm infection
Taenia sagmata
Taenia solium
'seatworm'- enterobius vermicularus-nematode rectum-most common worm infection in US.
What meds are used to treat pin worms
mebendazole or pyrantal pamoate
Ascaris lumbricoides- asymptomatic- most common worldwide worm infection- fruits and veggies- surgery for heavy infestation- treat: albendazole & pyratel panote, and mebanzote
Hookworm infection
necaturiasis- dogs, cats, and humans- adult attaches to villi of intestine and sucks blood- heavy infection- anemia
2 hookworm infections in humans
Ancylostoma duodenate and Necator americanus
Brain and spinal cord
12 pairs of cranial nerves, 31 pairs of spinal nerves, ganglia, sensory receptors
brain and spinal cord are covered w?
Meninges consist of?
3 membranes- outer, middle, and inner
Subarachtoid space
between arachnoid and pia- contains CSF
Cerebrospinal fluid
circulates brain ventricles, central canal of spinal cord and subarachoid, low level of compliment proteins, bacteria in CSF can multiply w/ little immune response
inflammation of the meninges- caused my microorganisms or injury- bacteria, virus, fungi and protozoans
aseptic meningitis
is viral infection
during CNS infection (meningitis)...
increase in lymphocytes, monocytes, and proteins.CSF remains clear
During bacterial infection of meningitis...
rapid increase in granulocytes and proteins- CSF becomes trubid
blood-brain barrier
barrier between nervous tissue and blood- help CNS resist infection
lipid soluable antibiotic- can enter brain
CNS invasion
inflammation of brain alters blood-brain barrier and allows drugs in- lymphatic and bloodstream
inflammation of the brain
brain and meninges
bacterial meningitis
1-2 days incub.- initial symp- nausea, vomit, stiff neck, fever headache-secondary: confusion, sleepiness, light sensitive, coma- less common, more severe.
Treatment of bacterial meningitis
penacillin G, ampicillin, amoxicillin, chloramphenicol, lefotaxime, vanc and ceftriaxone
Most common cause of bacterial meningitis
Strep. pneumoniae and Neisseria meningitis
Haemophilus influenza
used to be most common cause of bact. meningitis
E. coli and Kleibsiella normally causes meningitis due to?
head injury, brain or spinal injury, sepsis, or nonsocomial infection
Meningococcal meningitis
Neisseria meningitis- gram neg aerobic diplococcus- 5 serotypes: A,B,C,Y,W
Neisseria meningitis disease info:
spread resp or person 2 person- incub. 1-3 days- sore throat, headache, drowsiness, fever, stiffneck, photosensitivity- hemorrhagic skin rash= septicemia- can cause amputation
Haemophilus influenzae meningitis
H. influenza, gram neg, coccobacillus, normal flora of throat-can enter blood stream cause pneumonia, otis media, epiglotidis, meningitis-Resp droplet- IV antibiotics & steroids- 6 serotypes by their capsular polysaccharide.
H. influenza in children
Capsulated strain b= Hib
Pheumococcal meningitis
most common- streptococcus pneumoniae- gram +, encapsulated faculative anaerobic diplcoccus- 90 serotypes- vaccine for high risk- immune response against capsular serotype
pneumonicocci can also cause?
otitis media- complication include mustoidis and meningitis
Listeria meningitis
listeria monocytogenes- gram + coccobacillus-foodborne illness-fatal-4 days- from blood stream to CNS
Listeria meningitis symptoms
fever, personality changes, uncoordinated movement, seizures, conciousness, tremors
listeria in pregnancy
microphages hiding from immune system can cross placenta-early onset:infected during pregnancy- late onset: infect during childbirth- treated w/ antibiotics
acute and fatal, prolonged contracted skeletal muscles caused by tetanoplasmic
C. tetani
produces neuro toxin(exotoxin)- gram + rod anaerobic spore- toxins are what spreads it.
local tetanus
persistant contractions at site of injury- uncommon, mild, subsides
cephalic tetanus
rare, C.tetani in middle ear, head injury- cranial nerves
Generalized tetanus
most common, lock jaw, stiff neck, diff. swallowing, calf and pectoral spasms
Neonatal tetanus
newborns, umbilical stump- rare in developed countries
C.botulism, gram +, anaerobic, spore forming rod. produces neurotoxin- 7 serotypes A-G-A,B,E,F= human
Toxin A
most virulent- death if food is even tasted-60-70% mortality- CA, WA, CO, OR, NM
Toxin B
Europe and E. US - 25% mortality
Toxin E
Clostridium in marine sediments- seafood- Pacific NW, Alaska and great lakes.
Toxin F
C. baratii- infant botulism- also treats torticollis
Transmission of botulism
Toxin enters body, toxin binds to nerve endings @ neuromuscluar junction- stops release ACH, inhibits- fOODBORNE, infant, wound, inhalation
Symptoms of botulism
muscle weakness, dry mouth, diff swallowing, blurred vision, slurred speech, vomit and diarrhea, drooping eyelids
hansens disease-Mycobacteria leprae- gram +, acid fast, pleomorphic, intracellular- aerobic bacillus- waxy coating- skin, PNS, mucous membranes: nose, throat, eyes
tuberculoid- hypopigmented, PNS damage
lepromatous-more virulent- symmetric visions, nodules, plaques, thickened dermis
pinkeye- inflammation of transparent membrane that lines eyelid and eyeball- redness, itchy, roughness, discharge, teary
Bacteria that causes conjunctivitis
strep. pneumoniae, H.influenza, s. aureus, H.spp
Post polio syndrome
symptoms 30-40 years after polio
Viral meningitis
aseptic meningitis- mosquitos- no treatment, runs course-bulging of fontanel in infants
poliovirus- non enveloped ssRNA-
Abortive poliomyelitis
asymtomatic- 95%
Paralytic Poliomyelitis
1%- enters CNS- muscle paralysis-> death
zoonotic- ssRNA, bullet shaped-causes encephalitis- saliva- fatigue, muscle aches, anxiety, irritability, insomnia, headache, nausea, vomiting and abd pain.
PEP- rabies treatment
Post exposure propilaxis- 5 doses over 28 days
Arboviral encephalitis
biological vector-encephalitis- west nile virus
easter equine enceph.-human, horse, bird
can be fatal- high fever, headache, drowsy, irritable, nausea, vomit, confusion and coma-
St Louis Enceph- Flavivirus- aseptic meningitis or encephalitis
Lacrosse enceph.- rare- children- midwest
west nile- Africa, Asia- rash, headache, fever, diarrhea
West Nile poliomyelitis
inflamation of spinal cord
Fungal Infections
Cryptococcoisis neoformans
encapsulated yeast- inhalation or wound
Cryptococcal meningitis
immunocompromised- head ache, vomit, photophobia, blurry vision, stiff neck, seizure, confusion, coma
Cerebral toxoplasmosis
toxoplasmagondii-obligate intracellular- undercooked meat- speech, seizures, confusion, lethargy
African trypanosomiasis
sleeping sickness
Prion disease
TSE- transmibble spongiform encephal.- neurodegenerative disease, long incubation, always fatal, no cure-dementia, personality change, memory and brain funct.
Human disease
CJD- Degenerative brain disorder, sporadic, hereditary and acquired.
Variant-Creutzfeld Jacob (VCJD)
affects younger age- 29 yrs- foodborne by cattle (mad cow)
Gerstmann-Straussler-Scheinler (GSSS)
defective gene coding for PRNP protein- multicentric amyloid plaques in frontal lobe
Fatal familial insomnia
deteriorate motor functions- inherited or sporatic
endemic foretribe in New Guinea-cannibalism
Animal prion disease
Bovine spongiform ecephalopathy: madcow- chronic wasting disease, scrapie, feline SE, ungulate SE
cardiovascular: heart, blood and blood vessels and lymphatic: lymph, lymphatic tissue, vessels and organs- returns excess tissue fluid to cardiovascular system (direct acess)
tissue lining heart chambers
bacterial and fungal infections in heart
viral infections in heart muscle= myocarditis
membrane around heart- bacteria, virus and rarely fungi= pericarditis
infective and non infective
infective endocarditis
microbes= bacteria and fungi
non-infective endocarditis
trauma- formation & platelet & fibrin thrombi on valve- red spots and nodes
viral or parasite- causes heart failure- chest pain, arrythmias, leg swelling
viral, bacteria or fungi- chest pain, ankle/foot sweliing, dry cough, can't breath lying down, fever
Bloodborne Infectious disease
contain blood or fluids
microbes enter circulatory though lymphatic drainage
toxic condition, uncontrolled proliferation of bacteria or bacterial toxins
septic shock
from hypotension- loss of apetite, fever, chills, lethargic, accelerated breathing and heart rate
Rheumatic fever
Group A strep- inflammatory- heart, joints, brain, spinal cord, skin- longterm antibiotics- antiinflammatory
Necrosis- blood supply interrupted-> ischemia- enzymes from dying tissue further destroy surrounding tissue- surgery, antibiotic,
Clostridium perfringers
gram +, spore forming
Dry gangrene
distal limbs, ischemia, artenosclerosis
Internal gangrene
white gangrene-bleaching
Wet gangrene
mucous membranes, bed sores
Gas gangrene
gas in infected tissue
Zoonatic diseases
animals to human- viruses, parasites, prions
undulant fever- gram neg aerobic coccobacilli- flulike- can spread person to person if breastfeeding
rabbit fever- francisella tularensis- gram neg bacillus- blood & lymph, no person 2 person, skin abrasion, can lead to sepsis
Cat scratch disease
Bartonela henselae- aerobic, gram neg rod- saliva or scratch, blister at site, lymph node swell, fever, malase, headache, fever
Rat bite fever
Streptobacillus moniliformis- fac anaerobic, pleomorphic gram neg- PCN- can be fatal
Spirillum minus
gram neg spiral- Asia and africa
Symptoms of rat bite fever
chills, fever, vomit, pain in back, headache
Yersinia pestis- bubonic- swelling in lymph nodes, spetic
bacteria to lungs
Rocky mtn spotted fever
Rickettsia rickettsii- ticks- rash, fever, vomit, joints, diarrhea,
Lyme disease
Borrelia burgordorfi- black legged tick- spirochete- can cross placenta
stage 1 of Lyme disease
bulls eye rash, fever, and fatigue, headaches, stiff neck, muscle pain
stage 2 lyme disease
joints, heart, nervous system
Stage 3 lyme disease
severe arthritis attacks
ehrlica chattcensis- lonestar tick-prolonged: renal failure, intravascular cougulopethy, meningo enceph., resp. distress
epidemic typhus
Ricketsias prowazetil- human body louse
endemic (murine) typhus
Ricketsias typhi- rat flea
Scrub typhus
Orientia tsutsugamushi- chiggers
Relapsing Fever
Borrelia recurrentis- lice and tickstickborne= ornithodross tick= endemicLouseborn=human body louse=epidemic
glandular fever- epstein-barr virus aka human herpes 4- infects blymphocytes- sore throat, fever, fatigue, glands swell, saliva contact- no treatment
CMV- human herpes 5- infects monocytes, neutrophils, T-lymphocytes- body 2 body contact- no treatment
Viral hemorrhagic fever (VHF)
Adenaviridiae, filoviridae, bunyvridae, flavivirodae- vascular system, RNA, geographically restricted, contact w/ insect or host,
Treatment for Adenaviridae
Treatment for Filovirus
antibody-containing serum
systemic mycoses
histoplasmosis capsulatum- contact w/ spores, air, water, food
Organisms that cause Systemic mycoses
histoplasmosis capsulatum, Penicilliosis marneffei, Paracoccidioides brasiliensis, Coccidioides immitis
common vector born- plasmodium vivax, falciparum, ovale, malariae- targets erythrocytes- Anopheles mosquitos
Anopheles mosquito
carries plasmodium sporozoites
Uncomplicated malaria
enlarged spleen, fever, chills
P. falciparum
jaundiced, enlarged liver, increased resp rate- severe malaria- anemia, blood in urine, edema, shock, cerebral malaria, organ failure
caused by protozoa babesia-ticks- severe= fever, chills, anemia, organ failure- reproduce red blood cells
toxoplaso gondii- cat- uncooked milk, water, fecal-oral, mother 2 fetus, organ transplant
viseral= fatal form, cutaneus= common form, sore at bite site; diffuse cutaneous= skin lesions; mucocutaneous= skin ulcers that spread and damage nose and mouth tissue