CDKL5 (CYCLIN-DEPENDENT KINASE-LIKE 5) DISORDER AND ITS NEUROLOGICAL REPERCUSSIONS ON A PEDIATRIC PATIENT
INTRODUCTION: Little is known about the functions of the CDKL5 gene and its
proteins, but it's already possible to identify its intracellular location; in the
development early stages, there is a higher concentration in the cytosolic fraction,
after this period, a gradual increase in the CDKL5 concentration occurs in the
nuclear fraction (Oi et al., 2016), indicating citoplasmatic and nuclear regulation
activity from other genes. Additionally, it has been verified that mutations on the
MECP2 and CDKL5 genes cause similar phenotype, demonstrating MECP2 is possibly
phosphorylated directly by the CDKL5 (Pini et al., 2012). Clinical characteristics
found in the CDKL5 disorder include seizures at an early start (usually in the first 3
months of life), abnormal muscle tone, stereotyped hand movements,
gastrointestinal problems and severe global developmental delay (Fehr et al.,2013).
According to (Tao et al., 2004) , clinical attributes presented by patients with CDKL5
disorder can overlay characteristics from other alterations, like autism for example.
CASE DESCRIPTION: Patient L.C.L.F.S.S. born May 2nd 2015 (05/02/15) by a Csection
with gestational age of 38 weeks in a pregnancy without complications and
prenatal care done. At birth, patient exhibited head circumference of 36 centimeters
and Apgar score of 9 in the first minute and 10 in the second minute. The patient’s
development in the first month was expected of the age, yet with about 1 month
and 10 days started to present colics followed by seizure episodes. After this period,
she was hospitalized and performed a electroencephalogram, tomography and lab
exams. With about 2 months, she carried out an appointment with a pediatric
neurologist who ordered other exams, at first there was suspicion of West
syndrome. Already in 2017, it was performed a exam sequencing with confirmation
of CDKL5 disorder. Currently, patient displays symptomatology of epileptic crisis
that are hard to control, such fact is proven by the constant medicational
adjustment, to this moment, there has been no medication with total control over
the crisis, variations on the pattern of the electroencephalogram exam, atypic
hands, hypotonia, manifests visual interaction, presents good general state, no apathy, furthermore does not exhibit gastrointestinal alterations and feeds through oral administration, dismissing nutrition through nasogastric tube, a common aspect
in the syndrome. DISCUSSION: It is known that it is a disorder difficult to identify,
therefore new informations regarding this subject must be divulged in order to
provide a better understanding in the scientific community about the CDKL5
mutation. In the case described in patient L.C.L.F.S.S. there was a certain delay to
make the right diagnosis, causing damages to the patient and its family, such fact
reinforces, once again, the significance of the subject matter.
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