immune system Flashcards
difference between primary + opportunistic pathogens?
primary = cause disease in non-immunocompromised opportunistic = only infection in damaged host
3 ways primary pathogens cause disease
- intrinsic virulence
- toxic production
- induction of abnormal host response
what virus causes oral hairy leukoplakia
epstein barr virus
what virus causes cold sore
herpes simplex
what virus causes herpangina within mouth
enteroviruses
what virus are kaposis sarcoma associated with?
HHV 8
which number of herpes virus is herpes simplex?
1 + 2
how does HIV effect immune system?
CD4 decreased
treatment for aids?
NRTI
HAART
causes of hepatitis?
viral
drug interactions
autoimmune - uncommon
what is acute hepatitis?
self limiting liver inflammation
caused by: viral, acute alcoholic hepatitis, drugs, toxins, medications
what is chronic hepatitis?
clinical features of cirrhosis
caused by chronic Hep B or alcohol abuse
signs of liver disease in clothed pt
jaundice: yellow easy bruising spider naevi liver flap - asterisks sialosis dupuytrens contracture palmar erythema gynaecomastia
oral manifestation of gonorrhoea?
burning sensation in pharynx
oral manifestations of syphilis?
primary - painless ulcer on lip
secondary - mucous patches on mucosa, ulcers, lymphadenopathy
tertiary - gumma, glossitis, syphilitic leukoplakia
difference between bacteriostatic + bactericidal?
bacteriostatic = inhibit growth bactericidal = kills
difference between gram negative + positive bacteria?
- second outer membrane, don’t stain
+ thicker layer of peptidoglycan, stain
how do beta lactic e.g. penicillin antibiotics work?
inhibitor of peptidoglycan (cell wall) synthesis
how do tetracyclines + aminoglycoside antibiotics work?
inhibit protein synthesis from 30s ribosome site
how do macrolides + clindamycin antibiotics work?
inhibit protein synthesis from 50s ribosome site
how does metronidazol work as an antibiotic?
metabolised into toxic metabolites, interfere with DNA
how do sulphonamides act as antibiotics?
inhibit folate synthesis
what is vertical gene transfer?
spontaneous mutation, transferred during DNA replication
what is horizontal gene transfer?
conjugation - sex
transformation - death
transduction - viruses
how does aciclovir treat herpes?
analogue of purine nucleoside guanosine + incooprorated/interferes with replication of viral nucleic acid
what is AZT used to treat?
HIV/AIDS pts that are symptomatic
what must be considered if your pt has a prion disease?
can’t sterilise instruments - disposable only
2 conditions where amoxicillin is CI because of rash?
lymphocytic leukaemia + glandular fever
dental antibiotic best for use during pregnancy?
amoxicillin
try and avoid all medications in first trimester
why must tetracycline be avoided in pregnancy + breast-feeding?
dental discolouration
what 2 things is metronidazole CI with?
alcohol + warfarin
symptoms of immunodefiency
SPUR s = serious infections p = persistance infections u = unusual sites r = recurrent infections
6 clinical examples of primary immunodefiency?
- SCID
- X - linked agammaglobulinaemia
- common variable immunodeficiency
- chronic granulomatous disease
- chronic mucocutaneous candiasis
- Di George syndrome
what is SCID?
T cells absent, B cells might be absent
what is x-linked agammaglobulinaemia?
mutation in btk gene
low/absent B cells + reduced immunoglobulins
absent tonsils
what is DiGeorge syndrome?
thymus fails to develop - no/reduced T cells
causes of secondary immunodeficiency?
- malnutrition
- medication
- infection
- radiotherapy
- splenectomy
what oral manifestations of chronic granulomatous disease?
recurrent abscess + gingivitis
what antibody mediated type I hypersensitivity?
IgE
what antibodies mediate type II + III hypersensitive?
IgM + IgG
what mediated type IV hypersensitivity?
CD4 T cells
what happens in a type I hypersensitivity reaction?
IgE mediated degranulation of mast cells + basophils
release of histamine, heparin, lysosomal enzymes + proteases
increased capillary permeability + smooth muscle contraction
test for type I hypersensitivity
skin prick test + blood test for specific IgE
3 treatments for type I reaction?
- antihistamines
- steroids
- bronchodilators
what would result of patch test be in burning mouth syndrome?
negative - not an allergy
how do glucocorticoids causes immunosuprresion?
suppression of T cells
how do glucocorticoids cause anti-inflammatory?
decrease gene transcription for TNFalpha + interfere + IL1
complications of glucocorticoids
adrenal supression
osteoporosis
increased risk of infection
duodenal ulcers
how does cyclosporin cause immunosuprresion?
targets T cells via inhibition of IL2
2 types of calineurin inhibitor?
ciclosporin + tacrolimus
2 types of antimetabolite immunosuppressants?
azathioprine + methotrexate
how do monoclonal antibodies work and what are they used for?
inhibit cytokines involved in innate repsosne
autoimmune disease
how is the small intestine damaged in coeliac disease?
gluten activated series of immunological mechanisms
- loss of villi
- crypt hyperplasia
- chronic inflammatory infiltrate
what is good pastures?
autoimmune disease of kidney
what other autoimmune disease is associated with sjorgrens disease?
rheumatoid arthritis
what is ESR?
erythrocyte sedimentation rate
sign of inflammation
