EBV, HIV & Flu Flashcards
How common is Glandular fever?
Affects 90% of people
What organisms cause glandular fever?
EBV- Most common
CMV
HHV6
What is the incubation period of EBV?
4-6weeks
What is the pathophysiology of glandular fever?
Initial LYTIC phase = Oropharyngeal B cell infection
Spreads to spleen, liver & peripheral LN
Promotes humoral & cellular immune response
LATENT phase = EBV immortalises infected lymphocytes
What are the MAIN Sx of glandular fever?
TRIAD:
1) Mild fever
2) Pharyngitis
3) Lymphadenopathy (post triangle of neck)
What other features are commonly seen in glandular fever?
Malaise/fatigue- several months post-infection Tonsillitis Sore throat- Leukoplakia? Palatal petechiae + uvular oedema Macular rash Hepatosplenomegaly RARE: Jaundice, arthralgia, myalgia
How long does it take for splenomegaly to resolve in glandular fever?
3weeks post-presentation
How is Glandular fever investigated?
- MONOSPOT: Horse RBC agglutinate on exposure to heterophiles Ab
- Bloods: ↑WCC, ↑ESR, ALT/AST (mild)
- Blood Film: Atypical lymphocytes (large, irregular nuclei)
- Throat swab: Group A strep
- Abdo USS: Splenomegaly
How is glandular fever treated?
Self-limiting
Paracetamol
Severe: Steroids +/- Aciclovir
What should be avoided in glandular fever?
OH-: Protects liver
Contact sports: Splenic rupture
What are the complications of glandular fever?
Severe upper airway obstruction Hepatitis fulminans Severe thrombocytopenia & haemolytic anaemia EBV oncogenicity- LYMPHOMA Crescenteric GN
What is the incubation period of influenza?
1-4d
Infective 1d before Sx → 7d after Sx
How does influenza present?
Fever Headache Malaise Myalgia N&V Conjunctivitis & eye pain
How is influenza investigated?
Clinical Ix reserved for community surveillance purposes- Paired serology: Takes >2w Nasopharyngeal culture: Takes 1w PCR: 36hours
How is influenza treated?
Supportive: Bedrest + paracetamol
Antiviral: Oseltamivir (Tamiflu) if at risk group start within 48hours of Sx
Who is classed as ‘at risk’ and require antivirals in flu?
1) Chronic respiratory disease: COPD, CF, Asthma, Interstitial fibrosis, bronchiectasis
2) Chronic heart disease: IHD, Congenital HF
3) CKD/DM/CLD
4) ImmunoS
What are the complications of influenza?
Haemophilus infection → Epiglottitis
Pneumonia
Bronchitis
How is epiglottitis caused by Haemophilus infection treated?
ICU → Intubation
Blood Cultures
IV Cefuroxime/Cefotaxime
PROPHYLAXIS: Rifampicin to household
What is the pathogenesis of influenza?
Serotypes A, B & C
A = Most frequent, causes major flu outbreaks, further subdivided by ‘N’ & ‘H’ surface antigens
B = Circulates w/A causes less severe yearly outbreaks
C = Mild/asymptomatic, similar to common cold
What is the pathogenesis of HIV infection?
HIV binds to CD4 receptors on helper T cells, monocytes, macrophages, neural cells
CD4+ cells migrate to lymphoid tissue where virus replicates
Releases billions of virions → infect more CD4+ cells & deplete levels
Leads to immunoS = ↑risk infection + malignancy
How long does HIV take to become established in a host?
48-72hours
What are the different stages of HIV?
1) Sero-conversion
2) Clinical latency
3) ARC (AIDS related complex)
4) AIDS
What are the Sx in the sero-conversion stage of HIV?
PRIMARY infection → transient illness at 2-6w
Flu like Sx
Exacerbation of chronic inflammatory conditions (Eczema)
Mouth ulcers
Lymphadenopathy
Maculopapular rash on TRUNK
What happens in the clinical latency stage of HIV?
Asymptomatic infection
Persistent generalised lymphadenopathy → Nodes >1cm for >3m
What happens in the ARC stage of HIV?
↓CD4 + ↑HIV viral load
Prodrome to AIDS
Constitutional Sx (fever, night sweats, diarrhoea, ↓Weight)
Opportunistic infections
What happens when AIDS occurs?
Occurs 8yrs post-exposure
CD4 < 200 x 106/L
Death = 2yr if no HAART
What opportunistic infections may be seen in HIV?
ORAL: Candida, Hairy leukoplakia, Ulcers
SKIN: Rashes, Shingles, Psoriasis, Molloscum contagious, Warts, Tinea, Seborrhoeic dermatitis
RESP: TB, Pneumocystis, Jerovecii, Atypical pneumonia
CNS: Cryptococcal meningitis, CMV retinitis
Non-Hodgkin’s Lymphoma
What is the criteria for testing for HIV?
●Anyone who requests it ●Sex w/ person from high risk country ●Anyone w/STI ●All registering in GP where prevalence >2/1000 ●Partner has HIV ●Homosexual men or MSM ●IVDU ●HIV as differential
How is HIV diagnosed?
CONSET FOR TEST
1) POC test:
- Self-sampling kit: blood/saliva sent in post
- Rapid test kit: +ve result in 30mins
2) HIV p24 antigen PCR: 2-4w post-infection
3) HIV Ab ELISA: >4w post-infection
4) 4th gen serology test:↓ time between infection + diagnosis, repeat test at 3m to confirm
What is the next step if a +ve test result for HIV is found on a rapid test kit?
Must be confirmed by ELISA (HIV Ab + western blot)
What happens if a -ve result for HIV is found but there is still a high suspicion?
May be in false result due to low viral load:
INITIALLY HIV p24 antigen
THEN
HIV Ab at 6w AND 3m to confirm diagnosis
How is HIV monitored?
EVERY 3m measure: -HIV RNA levels -CD4 Count -Viral load -FBC EVERy 6-12m measure: -U&E (Creatinine) -Cl -HCO3 -LFTs (Bilirubin, lipid profile) -Glucose
How is HIV managed?
HAART: OD/BD 3HIV drugs from >2classes - x2 NRTI +1: -Protease inhibitor OR -NNRTI OR -Integrase inhibitor
How is HIV prevented?
PEP/PEPSE
Prevent sero-conversion in high risk
72hours of exposure
What are the compilations of HIV?
Conversion to AIDS
Drug resistance
Cancer: NHL, Kaposi, Invasive cervical cancer
How is HIV managed in pregnancy?
HAART Measure VL: 36w Vaginal delivery: VL <50 otherwise C-Section Neonate PEP for 4w AVOID breastfeeding
What are the common SE of HAART treatments?
Lipodystrophy N&V&D Rash Hepatitis Renal impairment Cushing's Bone problems
