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Harlequin Ichthyosis
By: Dan Hood, Matt Sharbaugh,
Brian Monterroso
WARNING!
• THE IMAGES YOU ARE ABOUT
TO SEE ARE REAL AND MAY
CAUSE SOME TO BECOME
QUEASY !
Biological Basis
• Intro:
– Harlequin Ichthyosis,
most commonly known
as harlequin’s disease
or HI is the most sever
form of keratinizing
disorders.
– The condition is
characterized by a
profound thickening of
the external layer of
the skin.
The Condition
• This rare but debilitating
condition occurs in 1 in
300,000 births.
• The babies are born with a
massive hard shell like
covering containing many
deep fissures.
• The babies also have
problems contracting their
eyes, mouths, and
appendages.
• They have a hard time moving
because where there are folds
on a normal baby there are
cracks on an HI child.
The Condition Continued
• In most cases the child is born prematurely.
• Most of the time the child dies within a few days
because of respiratory disease, bacterial
infections, feeding difficulties, and body
temperature regulation.
• Respiratory failure can result from restricted
movement of the chest muscles, and bacterial
infections occur from the lack of a protective
outer layer. The bacteria can easily enter the
baby through the fissures in the skin. The
cracks in the skin allow water and heat to
escape.
Surviving HI
• With improved neonatal
care more HI children
have the chance of
survival.
• The few survivors have
skin that turns dark red
and very scaly.
• The skin will eventually
from a scaly layer and dry
out so water retention
and sun protection are
concerns for the
survivors.
Detection
• One way to notice the
child has abnormalities is
through a sonograph
during the second
trimester.
• The sonograph shows
abnormal facial features
and small foot size in
ratio to the femur.
• A fetal skin biopsy can be
done but it is an invasive
procedure. From the
biopsy, tests can be run
on the child’s genes to
see if they are abnormal.
Genetics
• HI is caused by a
frame shift mutation
or a large deletion.
• The gene effected is
the ABCA12 in the
2q35 region, which is
involved in lipid
transport that impacts
the development of
the epidermis.
Genetics
• The condition is inherited autosomal recessively.
• This means an effected individual must have two
copies of the gene on chromosome 2 to have
the disorder.
• People with only one copy of the normal
ABCA12 gene are not effected by the disorder.
• The disorder does not show prevalence in
gender or racial background.
• There have been many cases of HI in southern
Iraq where mothers were exposed to uranium
oxide during the early stages of pregnancy.
Lipid Transport
• Members of the class of ABCA genes are
involved in lipid transport across cell
membranes. The proteins the gene
produces bind to ATP for active transport
of lipids to the stratum corneum, the outer
most layer of the skin. These lipids are
important for the protection of the skin.
Lipid Transport
Treatment
• The treatment of HI babies is quite extensive.
• The vitals of an HI baby must be constantly
monitored.
• Their eyes must be constantly kept moist and
shielded from the sun.
• The environment they live in must be constantly
kept sterile to protect from infection.
• They must have a salt solution applied followed
by a lubricant to facilitate the skin cells to fall off
and to keep the cells moist.
• Antibacterial pills and creams are also used to
fight infection.
Ryan Gonzalez
• Almost all HI children
die in infancy but
there are exceptions.
Birth
• He was born with harlequin
ichthyosis.
• Dr. Brian Saunders, a neonatologist, cared for Ryan during
the first critical moments of life.
• Ryan’s skin was so tight that it
was crushing his lungs.
• Accutane, a vitamin A derivative,
was used to keep the skin from
hardening.
• His scales became smaller and
thinner.
Life of a Harlequin
• He competes in triathlons.
• To keep his skin from
hardening, he covers himself in
lotion 7 times per day.
• He has to consume 7,500
calories per day.
• He tube feeds himself pure
protein every night while he
sleeps to help him produce
extra skin cells.
The View
• The condition was first described in South Carolina by Reverend
Oliver Hart.
• "On Thursday, April ye 5, 1750, I went to see a most deplorable
object of a child, born the night before of one Mary Evans in
‘Chas’town. It was surprising to all who beheld it, and I scarcely
know how to describe it. The skin was dry and hard and seemed to
be cracked in many places, somewhat resembling the scales of a
fish. The mouth was large and round and open. It had no external
nose, but two holes where the nose should have been. The eyes
appeared to be lumps of coagulated blood, turned out, about the
bigness of a plum, ghastly to behold. It had no external ears, but
holes where the ears should be. The hands and feet appeared to be
swollen, were cramped up and felt quite hard. The back part of the
head was much open. It made a strange kind of noise, very low,
which I cannot describe. It lived about forty-eight hours and was
alive when I saw it."
Live or Die?
• Two doctors in the Netherlands have
developed a checklist to determine
whether a newborn is suffering greatly or
not.
• If the doctors find that the child is suffering
greatly, they support euthanasia (assisted
suicide).
– “Our society has gone off the edge in terms of
protecting the vulnerable by forcing them to
suffer.”–Glen McGee
References
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http://ghr.nlm.nih.gov/condition=harlequinichthyosis#statistics
http://www.asylumeclectica.com/malady/archives/harlequin.htm
http://www.10news.com/health/3919722/detail.html
http://dermatology.wustl.edu/dermsub/caseofmonth/7-2000a.html
http://www.scalyskin.org/content.cfm?ContentID=222&ColumnID=6
http://www.jultrasoundmed.org/cgi/content/full/23/12/1653
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1199369
http://www.bbc.co.uk/dna/h2g2/A3816830
http://www.jci.org/content/vol115/issue7/images/large/JCI0525736.f1
.jpeg
• http://ribosome.med.miyazaki-u.ac.jp/RPDB/Map/RPL37A.gif
• http://www.answers.com/topic/harlequin-type-ichthyosis
• Chan, Y et. All. “Harlequin Ichthyosis in Association with
Hypothyroidism and Juvenile Rheumatoid Arthritis.” Pediatric
Dermatology. Vol 20. No. 5. p. 421-426. 2003.