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Dr Sarah Chamlin discusses Zika-linked skin
eruption, systemic drug therapy in children,
cognitive behavioural therapy for eczema
Sarah Chamlin MD, is Associate Professor of Pediatrics and Dermatology at Northwestern University Feinberg
School of Medicine, and a member of the
PracticeUpdate Dermatology
Advisory Board.
Zika virus and paediatric derm update.
Scott Norton
Dermatologists need to be alert for the skin eruption
of Zika virus infection. Zika virus, a Flavivirus, is part
of a family of mosquito-borne viruses which includes
West Nile virus and is transmitted by
Aedes
mosquitos,
specifically
A. aegypti
and
A. albopictus
. Zika virus
infection was first reported in the Zika forest in Uganda
in 1947, which later spread to the Micronesian island of
Yap, then French Polynesia. Further spread to Mexico,
Central America, the Caribbean, and South America
followed; the current epicentre is Brazil. Most often –
80% of the time – infection is asymptomatic, but 20% of
individuals experience a mild viral illness that may include
a rash, conjunctivitis, and arthralgia. Fever, myalgia,
and headache may also be noted. The rash has been
described as a generalised, erythematous morbilliform
eruption. The differential diagnosis includes dengue and
Chikungunya, although the rash and conjunctivitis are
more prominent with Zika. Zika is also thought to cause
lissencephaly – leading to the microcephaly reported in
Brazil – Guillain-Barré syndrome, and acute disseminated
encephalomyelitis. While only approximately 100 cases of
Zika have been identified in the US, more are anticipated,
possibly this summer; dermatologists may be on the front
line to make this diagnosis.
Controversies involving systemic drug therapy in
children.
Stephen Wolverton
Clinical decision-making about drug use in paediatric
patients with skin disease is often based on limited data
that are extrapolated from adult data or paediatric data
for another disease (eg, use of systemic drugs for juvenile
idiopathic arthritis or Crohn’s disease). A few lecture
pearls are listed below.
•
As a general rule, mg/kg dosing starts to roughly equal
adult doses at around 45 kg.
•
While subcutaneous methotrexate dosing has
approximately the same bioavailability as the oral
formulation, subcutaneous avoids the first-pass effect
in the liver and higher doses can be used. Unfortunately,
the use of subcutaneous drugs is more limited in
children due to pain.
•
A methotrexate test dose, 5 to 10 mg, with labs in 5 to
6 days may minimise pancytopenia risk. The paediatric
dosing range for methotrexate is 0.2 to 0.7 mg/kg, and
many patients respond at lower doses, even the test dose.
•
A FibroScan should be considered in children with
a high BMI on methotrexate to reassure clinicians of
long-term safety. While this scan is not routinely done
in children, it helps to decrease the number of liver
biopsies done in adult psoriasis patients.
•
Evidence for use of methotrexate, azathioprine, and
cyclosporine for severe and recalcitrant atopic dermatitis
is present in the literature. Much less evidence is
published for use of mycophenolate mofetil, which is
probably the safest to use. Research options emerging
for this population are omalizumab and dupilumab.
•
Several biologics are available for use in children with
severe, recalcitrant psoriasis, including etanercept,
adalimumab, infliximab, ustekinumab, and
secukinumab.
•
Recent articles suggest less frequent laboratory
monitoring for patients taking isotretinoin. Pregnancy
testing in women is an exception to this, and triglyceride
testing is the most volatile lab to follow, especially if
elevated at baseline. The approach to lab testing that
was reviewed was to stop monthly labs if stable after 2
months of testing.
•
There is no strong and supportive evidence proving an
increased risk of depression and suicide or inflammatory
bowel disease with isotretinoin use. Anecdotally, there
may be a very small subpopulation at risk for quickly
reversible depression.
Cognitive behavioural therapy & biofeedback in the
management of eczema.
Carisa Perry-Parrish
Children with atopic dermatitis may experience excessive
itching, sleep disturbance, diminished quality of life, poor
self-image, and peer teasing. Involvement of a paediatric
psychologist in the care of severely affected patients may
improve patient and family disease knowledge, treatment
adherence, and coping. In addition, scratching reduction
can improve disease severity.
Behavioural treatment examples for scratching reduction
include:
•
Habit reversal – Keep hands busy! Instead of scratching,
squeeze hands together, sit on hands, draw or colour.
•
Praise children for behaviours incompatible with
scratching – This will increase positive habits and
reduce inadvertent reinforcement of bad habits. Saying
“stop scratching” just doesn’t work.
•
Token system – Provide points or stickers for applying
moisturisers or taking a bath. Earn points for engaging
in habit-reversal techniques.
•
Stress reduction – Older children may benefit from
stress-reduction techniques such as deep breathing,
visualisation, and muscle relaxation.
PRACTICEUPDATE RHEUMATOLOGY & DERMATOLOGY
AMERICAN ACADEMY OF DERMATOLOGY 73RD ANNUAL MEETING
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