Makindo Medical Notes

Related Subjects: |Herpes Varicella-Zoster (Shingles) Infection |Chickenpox Varicella Infection |Varicella Cerebral Vasculopathy |Herpes Viruses |Herpes Zoster Ophthalmicus (HZO) Shingles |MonkeyPox |Mumps |Measles |Rubella (German Measles) |Epstein-Barr Virus infection |Cytomegalovirus (CMV) infections |CMV retinitis infections

90% of those with Infectious Mononucleosis develop a rash if given ampicillin or amoxicillin

About

• One of the causes of Glandular fever/Infectious Mononucleosis
• Infection is common and 90% of adults show evidence of infection.
• Similar clinical picture with CMV and toxoplasmosis
• Check for these as well as EBV especially in pregnancy / immunocompromised

Virology

• EBV is a gamma herpes virus
• Infection usually in young but may be delayed to adolescence even adulthood
• 50% of infections are clinical
• Saliva Aerosol/droplet spread - kissing classically
• Low contagion risk and isolation not required

Clinical: often subclinical

• Flu like illness, Headache, Malaise, Fever
• Large tonsils and pharyngitis and sore throat
• Generalised tender inguinal/axillary/cervical lymphadenopathy
• Jaundice with abnormal LFT's due to a mild hepatitis
• Splenomegaly (liable to rupture)
• Erythema multiforme, petechial rashes, periorbital oedema
• Encephalitis is rarely seen. Clinical severity increases with age

Pregnancy

• In pregnancy if heterophile antibodies are negative then check for CMV serology.
• It is important to recognise that CMV can produce an identical clinical picture.
• Active CMV infection during pregnancy can cause fetal abnormalities.
• Toxoplasma gondii can cause a similar clinical picture

Causes of Infectious Mononucleosis type picture

• Epstein Barr Virus infection, Cytomegalovirus infection
• Human Herpes Virus 6 infection, HIV-1 infection, Toxoplasmosis

Long term Complications

• Nasopharyngeal cancer, Burkitt's lymphoma
• Post transplant lymphoma, HIV related immunoblastic lymphomas
• Chronic fatigue syndrome
• Duncan's syndrome (X linked lymphoproliferative syndrome) due to SAP gene mutation

Differentials

• Streptococcal sore throat (liver and spleen and inguinal/axillary nodes usually normal)
• Cytomegalovirus infection
• Toxoplasmosis infection
• Viral hepatitis
• HIV seroconversion
• Lymphoma
• Leukaemia

Investigations

• FBC: mononuclear lymphocytosis with atypical lymphocytes, low platelets, neutropenia
• LFT: raised ALT and even a raised Bilirubin
• Atypical (CD8 +ve) T lymphocytes are common and can cause some worry about ALL
• Positive mono spot (Horse red blood cells) or Paul-Bunnell (Sheep RBCS) due to heterophile antibodies which agglutinate red blood cells in the second week of the illness. May be initially negative and so can be repeated.
• Serology: Anti IgM EBV early antigen (EA) titre and negative IgG EBV will confirm acute infectious mononucleosis
• Viral PCR in peripheral blood

Causes of Atypical lymphocytosis

• Epstein Barr Virus, Acute retroviral syndrome with HIV
• Viral hepatitis, Mumps, Rubella

Management

• Supportive, fatigue is common and can be debilitating. Full recovery can take 6 weeks. There is no role for antivirals against EBV.
• Aspirin can help reduce fever and sore throat. Tonsils may be very swollen and even cause airway problems which may need help
• Patients should be advised against contact sports until splenic enlargement has resolved as there is a risk of splenic rupture.
• Avoid Amoxil and Ampicillin as they cause a widespread macular-papular rash. If seen is a useful diagnostic test but really best avoided.
• A beta-haemolytic streptococcal pharyngitis superinfection should be treated with IV Benzylpenicillin or Erythromycin
• Prednisolone 30-60 mg OD for 5 days can lessen the severity of the severe pharyngeal oedema and symptoms, may be used in meningitis/encephalitis or if thrombocytopenia or haemolysis are present