Granulomatous and Reproductive Tract Infections Flashcards
Granulomatous Infections
-what are they
- Is a bacterial infection that causes granules (solid inflammatory reaction where WBC come and cocoon area off)
- Persistent bacterial infections characterised by strong local host immune response causing localised tissue damage
- if under skin, can see nodules (granules)
Mycobacterium
- features
- what stain is best to use?
- aerobic rods
- thick waxy wall: very resistant
- survive intracellularly (invasive)
- Acid fast stain best to use in Ziel Neelsen stain (appear red if retain Carbo fushion, blue if don’)
- Grow slowly, are many species
Classification of Mycobacterium
- > comes under the order: Actinomycetales
- are gram positive rods
- no endospores
- filamentous
-other family member = Actinomyces (not acid-fast)
Tuberculosis Complex
- 3 pathogens that can cause it (which are major pathogens)
- Human tuberculosis
- what it is usually due to
- vaccination
- how many ppl infected & die
- drug resistance
may be caused by major pathogens M. tuberculosis or M. bovis, or less harmful M. africanum
HUMAN TUBERCULOSIS
-can infect humans
-usu due to M. tuberculosis (occasionally M. bovis -> is cross reactivity therefore this is used in live attenuated vaccine)
-15 x 10^6 ppl infected per year, 3 x 10^6 die each year
-common in HIV patients (immunosuppressed)
*multidrug resistant strains (extensive drug resistant)
Human Tuberculosis
- characteristics of disease
- treatment and diagnosis
- Factors that determine lesions and severity
- where bacteria multiply
- what it causes
-chronic infections (very progressive)
-Stress can lead to breakdown
-military -> lung, liver, spleen-tiny spots like millet seeds on x-ray
*treatment can be 6 + months
Diagnosis: X- ray or Skin test (tuberculin)
Lesions & severity depend on;
-infective dose
-route of infection
-virulence
-resistance of host
-delayed type hypersensitivity immune response
*bacteria multiply w/in phagocytic cells causing granulomatous lesions, necrosis, caseation and calcification
M. avium complex
- what causes it
- what they cause
- relation to M. tuberculosis & M. bovis
-can be caused by;
M. avium
M. intracellulare
M. scrofulaceum
*are all occasional pathogens of humans and animals
-cause tuberculosis in humans (esp. immunosuppressed)
-also cause M. bovis and M. tuberculosis cross-reactios that make interpretation hard
TB skin test
-what it is used for & concept of test
- Determine infection w/ M. tuberculosis
- Inject bit of tuberculin purified protein derivative intradermally into skin to produce a wheal
- if have been exposed before, will have memory T cells -> they will all flock to site and cause a red reaction (is the DTH reaction)
Tuberculosis vaccine
- BCG vaccine (Bacille Calmette-Guerin)
- Live attenuated vaccine of M. bovis
- only lasts 10-15 years (not given a booster)
Mycobacteria causing skin lesions
-M. ulcerans - ulcer
-M. marinum - fish and swimming pool ulcers
M. leprae - cause of lepracy
M. lepraemurium
Leprosy
- where it multiplies
- where infiltrates
- spectrum of activity
- treatment?
- Possible transmission
- what it causes
*multiply in Schwann cells = anaesthesia + muscle paralysis eventually
-grows v. slowly (20 yrs after infection before clinical symptoms show)
-Bacteria infiltrates skin lesions
-Spectrum of activity: granulomas to little response
*is a common disease
-Responds to treatment of Dapsone and rifampicin (combo of antibiotics used)
Transmission: may be close contact, aeosol droplets or insect bites
-causes disfiguration due to granulomas, can effect mucousal surface of resp tract and eyesight
Mycobacterium causing enteritis
- M. paratuberculosis
- what it effects
- infiltration
- M. paratuberculosis
- causes chronic wasting and diarrhoea in cattle
- no recovery
- v. slow growing in vitro
- likes mucosa of lower gut
- infiltrates macrophages
- disease in > 18 m.o. following stress
Brucellosis
- features of bacteria
- B. abortus (what species)
- what it is causes
- In australia?
- Small, non-motile Gram neg coccobacillus
- fastidious, strict intracellular parasites (invade cells)
- B. abortus - cattle
- zoonotic (humans, sheep, goats, pigs)
- causes reproduct. tract infection in cattles
- eradicated from Australia
Brucellosis
- chronic disease
- how transmitted (3)
- affect in females, males and humans
- Chronic disease: small granulomas in lymph nodes, udders, joints to intermittent malaise, shedding in milk (can be transmitted by milk)
- can also be spread by contact with aborted material/vagina
- bacteraemia, necrotic placentitis + abortion
- Orchitis in males (inflammation of testes)
- In humans: undulant fever (rises and falls)
B. melitensis
B. suis
B. canis
B. melitensis: worldwide (but not Aus), severe zoonosis
-abortion/orchitis/mastitis
-unthrifty and lame
G. suis
-pig version (is in Qld; causes herd infertility)
-Coitus important in transmission
-zoonotic
B. canis
-uncommon in dogs
-abortions
-zoonoticVaccines for Brucellosis
-what diagnostic tests look for
- Live or killed
- diagnostic tests based on; antibiotic detection (looking at B cells - in tuberculosis looking at T cell response)
Campylobacter
- Features of bacteria
- what commonly found on
- spiral, curved, slender gram negative rods
- many species, motile
- Fastidious, special media and incubation conditions required
- ingested raw meat (esp. chicken)
- GI disease (gives v. painful cramps)
- also involved in food poisoning
- is a notifiable disease
Gastrointestinal infections (Campylobacter)
- where carried
- most common cause of?
- what some of strains can cause
- resistance?
- carried in GI tract of poultry, pigs, etc,
- is THE most common cause of human food poisoning
- esp. consumption of chicken, raw milk, exposure to contaminated water)
- sometimes isolated from bloodstream
- Many strains; some have cytotoxins/enterotoxins - can cause enteritis,, diarrhoea and occ. bacteraemia
- rarely can cause Guillain-Barre syndrome (autoimmune disease that affects CNS)
- reactive arthritis: demyelination = paralysis
- Ciprofloxacin resistant strains in US poultry -> worrying!
Helicobacter pylori
*famous Australian!
- GI associated
- Ass. w/ gastritis/gastric and duodenal ulcers in humans
- can lead to cancers
- Urease activity neutralises acidicity in microniches in stomach (allows bacteria to grow and gives you really bad breath)
Vibrio
- characteristics (special shape)
- B. cholerae (serotype 01) -> what it causes
- where they reside
- what cholera toxin does
-slender, gram neg
-comma shaped rods, motile
-water borne
V. Cholerae (serogroup 01)
-Cholera -> is classic or El-Tor strain (biotypes cause cholera, produce hemolysins)
-reside in aquatic environments, coastal waters etc
-Cholera toxin;
-severe watery diarrhoea ass. w/ faecal contamination of drinking water/food
-pandemics
-endemic in many regions
Non 01 (serotype) Virbrios
V. Parahaemolyticus
V. vulnificus & V. alginolyticus
-what they do
-Less severe disease
-widespread -> mild diarrhoea
V. parahaemolyticus
-halophilic
-asso. w/ seafood (esp raw seafood in japan)
-cause of diarrhoea
V. vulnificus & V. alginolyticus
-present in seawater
-cause of skin infection, sometimes developing into fatal septicaemia (flesh-eating bacteria)
-occ. diarrhoea
-ass. w/ eating shellfish
-some vibirios cause disease of fish, oysters
