ebv
EBV / glandular fever / infectious mononucleosis
introduction
Epstein-Barr Virus (EBV) is the virus that causes glandular fever (infectious mononucleosis or IM)
a frequent infection, particularly in young adults, mainly due to spread via saliva such as kissing or sharing drinks
EBV is transmitted via intimate contact with body secretions, primarily oropharyngeal secretions.
EBV infects the B cells in the oropharyngeal epithelium.
The organism may also be shed from the uterine cervix, implicating the role of genital transmission in some cases.
On rare occasion, EBV is spread via blood transfusion.
A rapid and efficient T-cell response results in control of the primary EBV infection and lifelong suppression of EBV.
Ineffective T-cell response (such as in those on immunosuppressants for Mx of transplants) may result in excessive and uncontrolled B-cell proliferation, resulting in B-lymphocyte malignancies
clinical features of acute EBV infection
incubation period 1-2 months
most patients are asymptomatic (50% of 5yr olds and 90% of adults show serologic evidence of past infection)
when infection occurs during adolescence, it causes infectious mononucleosis pharyngitis picture in ~50%
when infection occurs in the elderly, it mainly causes a viral hepatitis picture
adolescent infectious mononucleosis
fever
malaise
fatigue may be profound initially, but usually settles after a variable period but often takes 3 months, but may be longer in some resulting in
Chronic fatigue syndrome
pharyngitis - often pustular with bilateral large inflamed “kissing” tonsils which may compromise airway, and later, palatial petechiae (these also can occur in Strept tonsillitis)
generalised
lymphadenopathy - in particular, the finding of
posterior cervical LN's helps differentiate it from bacterial tonsillitis which generally only causes anterior cervical lymphadenitis, but adenitis is uncommon in the elderly who mainly present with an anicteric viral
hepatitis.
splenomegaly may be present but usually returns to normal by 3 weeks
abnormal LFTs are common but jaundice occurs in < 10% of young adults and in ~30% of the elderly with acute EBV
early, transient, faint macular rash is common but easily missed
early and transient bilateral upper-lid edema
widespread macular rash may occur, but particularly likely if the patient has received amoxycillin
leukocytosis, rather than leukopenia, often with atypical lymphocytes > 20% +/- thrombocytopenia
Monospot IM screen may be negative in the first week or two and overall has a sensitivity of 85% (in children over age 2yrs) and specificity of 100%
ESR is usually raised (but is not so in Strep tonsillitis!)
rarely may cause:
pancreatitis
acalculous cholecystitis
myocarditis
mesenteric adenitis
myositis
glomerulonephritis
optic neuritis
transverse myelitis
aseptic meningitis
encephalitis
meningoencephalitis
cranial nerve (CN) palsies (particularly CN VII)
Guillain-Barré syndrome
selective immunodeficiency to EBV, which occurs in persons with X-linked lymphoproliferative syndrome, may result in severe, prolonged, or even fatal infectious mononucleosis
fatal hepatic necrosis is a rare complication, and is more likely in males
ED Mx of presumed acute EBV pharyngitis/tonsillitis
FBE, IM screen +/- LFTs are generally performed
if significant dysphagia or potential airway risk, admit for iv fluids and iv dexamethasone
patients with splenomegaly should be warned to avoid contact sports
if clearly EBV and not Strept tonsillitis, avoid antibiotics, and particularly amoxycillin as likely to develop a florid rash
encouraged to rest as much as possible and to refrain from active physical activity for 3 weeks
seek specialist advice if immunocompromised or rare complication
long term sequelae
neoplasia risk:
endemic Burkitt lymphoma in children in malarial countries such as Africa
Hodgkin's lymphoma - 3x risk; 40% of HL cases in Western countries are EBV genome-positive
Non-Hodgkin's lymphoma
hairy leukoplakia
leiomyomas and leiomyosarcomas in immunocompromised children
nasopharyngeal carcinoma appears to be always caused by EBV, high prevalence in southern China and other parts SE Asia
Most instances of post-transplant lymphoproliferative disorder (PTLD) are associated with EBV.
B-cell lymphomas (post-transplant lymphoma PTL) risk if on immunosuppressants for Mx of transplants
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there is evidence that infection with the virus is associated with a higher risk of certain autoimmune diseases, especially dermatomyositis, systemic lupus erythematosus, rheumatoid arthritis, and Sjögren's syndrome
ebv.txt · Last modified: 2016/04/15 16:10 (external edit)