Infectious diseases I Flashcards
Name the different human herpesviruses
HHV-1 = HSV1 HHV-2 = HSV2 HHV-3 = VZV HHV-4 = EBV HHV-8 = HHV-8; Kaposi's sarcoma (purple, purpural lesion)
Compare the presentations of HSV1 and HSV2
HSV1
= cold sores (herpes labialis), herpetic whitlow (lesion on finger), systemic inflammation
= keratoconjuctivitis, herpes simplex meningitis/encephalitis
HSV2
= life long genital herpes, flu-like prodrome, shallow ulcers, urethral discharge, dysuria, fever + malaise
Chicken pox summary card
Primary infection of varicella zoster, typically occurs in children
= prodromal malaise, mild pyrexia, generalised pruritic vesicle rash (mainly face and trunk), contagious from 48hr before rash and until all vesicles crusted over (7-10 days)
= children mx w/ calamine lotion, analgesia, antihistamines
= adults mx w/ acyclovir/valacyclovir/famciclovir if < 24 hr onset
= can lead to bacterial sepsis, pneumonia, encephalitis, haemorrhagic complications
Shingles summary card
Reactivation of varicellar zoster, typically occurs in elderly
= occur due to stress, tingling in dermatomal distribution, followed by painful skin lesions, recover 10-14 days
= 1st line: valacyclovir/famciclovir
= 2nd line: acyclovir if < 72 hr of appearance of rash for 7 days
= can lead to myelitis, meningoencephalitis, cranial nerve palsies, vasculopathy, GI ulcers, pancreatitis, hepatitis
Presentation of infectious mononucleosis
Glandular fever: primary EBV, proliferation of B lymphocytes as incorporation of viral DNA into host DNA
= lymphadenopathy (posterior cervical chain), fever, pharyngitis (tonsillar exudates), hepatosplenomegaly; jaundice
= most pts make uncomplicated recovery in 3-21 days
Ix and mx for mono
Ix
- FBC, blood film (atypical lymphocytes), heterophile antibodies (monospot test), EBV specific antibodies, PCR_EBV DNA detection
Mx
- Supportive care; anti-inflammatories, analgesia
- Corticosteroids; if severe case (haemolytic anaemia, obstructive pharyngitis, severe tonsillar swelling)
*amoxicillin/ampicillin CONTRAINDICATED as leads to widespread maculopapular rash
Which EBV specific antibodies would be present for the following:
a) -ve EBV status
b) early primary infection
c) acute primary infection
d) past infection
a) no antibodies present
b) EBV VCA IgM present
= viral capsid antigen, IgMnow (like meow)
c) EBV VCA IgM, EBV VCA IgG
= viral capsid antigen, IgMnow
= viral capsid antigen, IgGone
d) EBV VCA IgG, EBNA
= viral capsid antigen, IgGone
= nuclear antigen (6-12 weeks after onset)
Presentation of HIV
Normally due to the complications from reduced CD4+ T-cells
= bacterial infection (staphylococci, mycobacteria, salmonella, strep., H. influenzae)
= viral infection (CMV, HSV, HPV, VZV, EBV)
= fungal infection (invasive aspergollis, pneumocystic pneumonia, candida)
= protozoa infection (toxoplasmosis, microconidia, crypto)
HIV associated tumours
Kaposi’s sarcoma
= AIDS-defining, HHV-8, pink/purple patch on skin/in mouth
SqCC
= anal/cervical due to HPV
Lymphoma
How is HIV transmitted and what are its stages of infection?
Sexual contact, pregnancy/childbirth and breastfeeding, IVDU, occupational exposure, blood transfusion/organ transplant
- Flu-like
- Feeling fine
- Falling count (CD4+ T cells)
- Final crisis (AIDS)
Ix for HIV
1st line = ELISA, confirm w/ Western Blot = serum HIV rapid test = serum HIV DIVA PCR in infants = CD4+ count = serum viral load (HIV RNA)
Other tests
= drug resistance test to determine therapy
= screen for Hep B + C
= screen for syphilis (Treponema pallidum)
= screen for TB (tuberculin skin test)
= FBC, U&Es, LFTs etc.
What is hairy leukoplaki associated with?
Irregular, white, painless plaques form on lateral tongue and cannot be scraped off
EBV-mediated in HIV + organ transplant pts
Candidiasis summary card
Thrush; candida albicans
= oral: dysphagia
= vaginal/balanitis: thick discharge, itching, redness, soreness
= disseminated fever, hypotension +/- leucocytosis
= associated w/ diaper rashes, infective endocarditis
Ix are not routine, clinical diagnosis but may want to exclude:
= UTI (urinalysis)
= Diabetes (fasting/random glucose, glucose tolerance test)
= STIs (vaginal pH test)
= HIV (antibody test)
Types of candidiasis and pts they’re associated with
Oral candidiasis and oesophageal thrush
= immunocompromised
Vulvovaginitis
= diabetics, use of Abx
Disseminated candidiasis
= neutropenic pts
Tonsillitis summary card
Acute infection of parenchyma of palantine tonsils
= pain on swallowing, fever > 38, tonsillar exudate, sudden onset sore throat, tonsillar erythema and enlargement, anterior cervical lymphadenopathy
= viral: rhinovirus, coronavirus, adenovirus, EBV
= bacterial: group A strep, mycoplasma pneumoniae, Neisseria gonorrhoea
Ix: rapid strep antigen test, throat culture