Blood Borne Viruses* Flashcards
Transmission of HIV?
Sex Injecting drugs Blood products Vertical transmission Organ transplant People can be high risk or unknown risk
What is AIDS?
Acquired immune deficiency syndrome
Causing a weakened immune system
<200mm of CD4 in blood
Clinical stages of HIV presentation - I-IV?
Stage I: - asymptomatic
Stage II:- weight loss, herpes, and minor mucocutaneous infections- hard to differentiate to any other disease
Stage III:- oral hairy leukoplakia, oral thrush and severe bacterial infect
Stage IV:- HSV, Kaposi’s sarcoma, candidiasis and pneumocystis pneumonia
HIV immunology - what is affected?
Destruction of the CD4 T-helper lymphocytes
Early diagnosis leads to better outcomes so test at any suitable opportunity
Undetectable = Untransmittable
Undetectable = Untransmittable
Candidiasis - early and late disease and differential diagnosis?
Early diseases assoc with mild oral candida
Late disease leads to extensive oral and oesophageal candidiasis
Differentials: - diabetes- steroids- antibiotics
Oral manifestations of HIV - types? relation with HIV? cause?
Oral Hairy Leukoplakia:- diagnostic- EBV virus- asymptomatic
Oral ulcers:- related to many diseases- present in acute or late HIV- multiple severe = HIV
Warts:- severe = HIV
Oral lymphoma:- unusual sites = HIV
Kaposi’s sarcoma:- tumour arising from endothelium- found on skin and palate
Other conditions:- gingivitis, thrombocytopenia, oral malignancies and HSV
Syphilis:- snail-track ulcer- use of pre-exposure drugs stops HIV transmission but has created an increase in other STDs
Molluscum contagiosum:- pox virus
Seborrheic dermatitis:- immunodeficiency- found at nasal folds
Drug side effects for HIV patients - appearance related?
Lipodystrophy causes facial changes due to fat redistribution
Occupational HIV exposure risk - risk ratio? risk factors?
3/1000 injuries
Factors:- deep injury- visible blood on instrument- needle stick injury from vessel- HIV related illness
Saliva poses risk to dentists, as most likely to be contaminated with blood
What to do following possible exposure?
Wash injury with soap and water without scrubbing
Free bleeding of the wound to be encouragedIrrigation with water
What to do after possible exposure?
Post-exposure prophylaxis
Reduces chance by 80%Start the sooner the better
Hepatitis B - virus distype? recovery? chronic hep symptom? treatment? antibodies - immunity chronic and acutely infected? to practice? risk ratio?
DNA virus >95% of people make a full recovery 20% of people with chronic hep B will develop cirrhosis and 1/10 will develop liver cancer Treated with tenofovir HBsAg, anti-HBc/s and IgM anti-HBc Chronic - HBsAg and anti-HBc Acute - HBsAG, anti-HBc and IgM anti-HBc Immunity - anti-HBsHBV DNA viral load must be <200 IU/ml on continuous antiviral therapy RR - 1:3
Hepatitis C - virus type? severity? progression? treatment? to practice? risk ratio?
RNA virus
80% develop chronic infection and 10-30% will develop cirrhosis
Treated with interferon-free direct-acting antivirals (DAA), polymerase inhibitors and NS5a inhibitors
Dentist needs to be Hep C RNA -ve
RR - 1:30
HIV - virus type? variations? infection? treatment? to practice? risk ratio?
RNA retrovirus HIV-1/2 Infects CD4 T cells Treated by HAART Below 200 copies/ml, viral load testing every 3m, register with UKAP and on combination therapy with supervision RR - 1:300
Occupational exposure to blood protecting patients and staff - EPP? why is dentistry higher risk?
Exposure prone procedures
Invasive procedures that risk injury to worker resulting in exposure to blood and/or sharp instruments in a confined area
