Discussion
Dyke, Davidoff and Masson recognized and reported the first cases of
this syndrome in 1933.1 Almost a century later, less
than 100 cases reported worldwide but its global incidence is still
unknown. DDMS falls in the category of epilepsy with brain structural
abnormalities of the International League Against Epilepsy
classification (ILAE).12 The clinical manifestations
encompass a focal and/or generalized drugs-resistant epilepsy,
hemiparesis or hemiplegia, facial or body asymmetry with atrophy and
mental retardation as seen in our patient.2, 3 Besides
these manifestations, rare cases may include cerebellar atrophy,
neuropsychiatric disorders and ear malformations.3However, the disease phenotype can vary from one patient to another, and
some may not present epilepsy, mental retardation or body
asymmetry.13 The patient was referred for convulsive
status epilepticus that led to the diagnosis as seen in previous
reports.14 DDMS is usually diagnosed in childhood,
mostly in the first decade, but cases of late diagnosis or adults cases
were also reported.2 Although the syndrome is easily
recognizable by clinical and brain imaging findings, the diagnosis delay
was eighteen years in our patient. This is likely due to the limited
access to specialists who could further investigate with brain imaging
as this was not performed before we saw the patient. A similar case with
a long diagnosis odyssey was reported in a patient from
Nigeria.11 Brain CT-scan or MRI have contributed to
facilitate the diagnosis by typically showing hemi cerebral atrophy,
ipsilateral thickening of the skull bone and ipsilateral hyper
pneumatization of the frontal and paranasal sinuses.15In our case, the hyper pneumatization of the frontal and paranasal
sinuses and the thickening of the skull bone were bilateral. To the best
of our knowledge, these brain imaging findings have not been previously
reported. This case could be another phenotypic variant of DDMS that
might be due to some specific genetic factors as suggested by previous
studies2 or to recurring brain. Although our patient
fulfilled the diagnosis criteria of DDMS, other diseases such as
Rasmussen’s encephalitis (RE), hemiplegia-hemi convulsion epilepsy (HHE)
syndrome and Sturge Weber syndrome (SWS) are also
possible.15, 16 However, in RE and HHE there is no
skull bone thickening or a hyper pneumatization of the sinuses that are
pathognomonic radiological findings in DDMS as seen in the patient
presented here. In addition, in HHE syndrome, the seizures are in the
hemiplegia/hemiparesis side without secondary generalization. SWS is a
neurocutaneous syndrome characterized by facial birthmark also called
port-wine birthmark and cerebral vascular calcifications which were
absent in our patient. The management of DDMS is challenging, especially
in resource-limited settings due to the resistance to several
antiepileptic drugs (AED). The treatment is based on the use of a
combination of AEDs and the surgery with hemispherectomy is an option in
the case of refractory epilepsy.14