Viral exanthemas

Question 1

What is an exanthema?

Answer 1

Exanthem is an eruptive widespread rash.

Question 2

What is 1st?

Answer 2

Measles

Question 3

What is 2nd?

Answer 3

Scarlet fever

Question 4

What is 3rd?

Answer 4

Rubella

Question 5

What is 4th?

Answer 5

Duke’s disease

Question 6

What is 5th?

Answer 6

Parovirus B19 - slapped cheek syndrome

Question 7

What is 6th?

Answer 7

Roseola Infantum

Question 8

What do you need to do if someone has measles?

Answer 8

Tell Public Health England → notifiable disease.

Question 9

How is measles spread?

Answer 9

Through respiratory droplets from coughing, sneezing, close personal contact or direct contact with nasal or throat secretions → highly contagious.

Virus can remain transmissible for up to 2 hours after its spread on surfaces.

Question 10

What is the incubation period and infection period for measles?

Answer 10

10 days. Measles is self resolving after 7 – 10 days of symptoms. Once infected, the person is infected from the onset of symptoms till 4 days after the rash has appeared.

Question 11

What are the risk factors for measles?

Answer 11

Exposure to the measles virus, Lack of prior immunisation against measles, Failure to respond to the vaccine.

Question 12

What are the presentations of measles?

Answer 12

A fever of 39°C or more without antipyretics, decreases after the rash develops, cough, conjunctivitis, coryza, diarrhoea, and Koplik’s spots: small, red spots with blue-white centres seen on the buccal mucosa.

Koplik’s spots are pathognomonic of measles; appearing one to two days before the onset of the rash.

Question 13

What is the differential diagnosis for measles?

Answer 13

Rubella, parvovirus B19, scarlet fever, roseola infantum, EBV, drug eruption.

Question 14

What investigations are done for measles?

Answer 14

Measles-specific IgM/IgG serology (ELISA) is generally performed, and the presence of measles-specific IgM indicates acute infection.

Question 15

What is the management for measles?

Answer 15

General supportive treatment includes rest, advice regarding adequate fluid intake, and antipyretics: paracetamol/ibuprofen for symptomatic relief.

Question 16

What is the general advice for measles?

Answer 16

Don’t attend work or school for at least 4 days after the rash has appeared & avoid contact with those who are susceptible.

Question 17

What are the complications of measles?

Answer 17

Otitis media, pneumonia, convulsions, encephalitis, sight impairment, death.

Question 18

What is scarlet fever associated with?

Answer 18

Scarlet fever is associated with group A streptococcus infection, usually tonsillitis.

Question 19

What is scarlet fever caused by?

Answer 19

Scarlet fever is caused by an exotoxin produced by the streptococcus pyogenes (group A strep) bacteria.

Question 20

What type of rash is associated with scarlet fever?

Answer 20

It is characterised by a red-pink, blotchy, macular rash with rough “sandpaper” skin that starts on the trunk and spreads outwards. Patients can have red, flushed cheeks.

Question 21

What are the other features of scarlet fever?

Answer 21

Fever, lethargy, flushed face, sore throat, strawberry tongue, cervical lymphadenopathy.

Question 22

What is the treatment for scarlet fever?

Answer 22

Treatment is with antibiotics for the underlying streptococcal bacterial infection, specifically phenoxymethylpenicillin (penicillin V) for 10 days.

Question 23

What do you need to do if someone has scarlet fever?

Answer 23

Scarlet fever is a notifiable disease and all cases need to be reported to public health. Children should be kept off school until 24 hours after starting antibiotics.

Question 24

What other conditions can patients have associated with group A strep infection?

Answer 24

Post-streptococcal glomerulonephritis, Acute rheumatic fever.

Question 25

How is rubella spread?

Answer 25

**Respiratory droplets** → highly contagious.

Question 26

What is the incubation period for rubella?

Answer 26

Symptoms start 2 weeks after exposure.

Question 27

What is the presentation of rubella?

Answer 27

Milder ***erythematous*** ***macular*** rash compared with measles, starts on the face and spreads to the rest of the body, lasts 3 days, can be associated with mild fever, joint pain, sore throat, and enlarged lymph nodes (***lymphadenopathy***) behind the ears and at the back of the neck.

Question 28

What is the management for rubella?

Answer 28

Management is supportive and the condition is self-limiting.

Question 29

What do you need to do if someone has rubella?

Answer 29

Rubella is a ***notifiable disease*** and all cases need to be reported to ***public health***. Children should stay off school for at least 5 days after the rash appears and should ***avoid pregnant women***.

Question 30

What are the complications of rubella?

Answer 30

***Thrombocytopenia*** and ***encephalitis***.

Question 31

What are the risks if a pregnant lady has rubella?

Answer 31

Dangerous in ***pregnancy*** and can lead to ***congenital rubella syndrome***, which is a ***triad*** of **deafness, blindness and congenital heart disease**.

Question 32

What is 5th disease also known as?

Answer 32

**Parvovirus B19** is also known as, ***slapped cheek syndrome*** and ***erythema infectiosum***.

Question 33

What is the progress of illness in 5th disease?

Answer 33

Starts with **mild fever, coryza and non-specific viral symptoms** such as muscle aches and lethargy. After **2 – 5 days**, the **rash** appears quite **rapidly** as a **diffuse bright red rash on both cheeks**, as though they have “***slapped cheeks***”. A few days later a ***reticular*** mildly erythematous rash affecting the trunk and limbs appears.

Question 34

How long does 5th disease last?

Answer 34

The illness is **self limiting** and the rash and symptoms usually fade over **1 – 2 weeks**.

Question 35

When is 5th disease infectious?

Answer 35

It is **infectious prior to the rash forming**, but **once the rash** has formed they are **no longer infectious** and do not need to stay off school.

Question 36

What is the management in the normal population for 5th disease?

Answer 36

Healthy children and adults have a **low risk of any complications** and are managed **supportively** with plenty of fluids and simple analgesia.

Question 37

Which patients are at risk of complications from 5th disease?

Answer 37

**Immunocompromised patients**, **pregnant women**, patients with haematological conditions such as **sickle cell anaemia**, **thalassaemia**, **hereditary spherocytosis** and **haemolytic anaemia**.

Question 38

What do these patients require?

Answer 38

These patients require ***serology testing*** for parvovirus to confirm the diagnosis, checking of the ***full blood count*** and ***reticulocyte count*** for ***aplastic anaemia***.

Question 39

What are the complications of 5th disease?

Answer 39

***Aplastic anaemia***, encephalitis or meningitis, pregnancy complications including fetal death, rarely hepatitis, myocarditis or nephritis.

Question 40

What is 6th disease also known as?

Answer 40

**Roseola infantum** is also known as just ***roseola***.

Question 41

What is 6th disease caused by?

Answer 41

By ***human herpesvirus 6*** (***HHV-6***) and less frequently by ***human herpesvirus 7*** (***HHV-7***).

Question 42

What is the incubation period for 6th disease?

Answer 42

**1 – 2 weeks after infection**.

Question 43

What is the disease progression for 6th disease?

Answer 43

It presents 1 – 2 weeks after infection with a ***high fever*** (up to 40ºC) that comes on suddenly, lasts for 3 – 5 days and then disappears suddenly. There may be coryzal symptoms, sore throat and swollen lymph nodes during the illness. When the fever settles, the rash appears for 1 – 2 days. - The rash consists of a mild erythematous macular rash across the arms, legs, trunk and face and is not itchy.

Question 44

What is the main complication of 6th disease?

Answer 44

The main complication to be aware of is ***febrile convulsions*** due to high temperature.