Dr.Subbulakshmi P S**, Dr.Praveena Bhaskaran**, Dr.Vinayan K.P*, Dr.Vaishakh Anand*, Dr,C.Jayakumar**
*Department of Paediatric Neurology, **Department of Paediatrics, AIMS,Kochi
Five years old female child, first child of non-consanguineous marriage from Saudi who was apparently normal six months back, suddenly developed postural instability and decreased clarity of speech with altered behaviour. Her growth parameters were within normal limits and age appropriate milestones were attained. Immunized upto age as per Saudi schedule
Neurological examination showed a normal sensorium with ataxia, intentional tremors with a decreased power and tone with normal reflexes. Abdomen examination showed no masses with a soft abdomen. Other systems were within normal limits. The symptoms were progressive in nature.
USG and CT abdomen and MIBG (1odine 131 meta Isobel guanidine scan)done revealed the presence of a suprarenal mass and excision was done following which she was doing well for a month.
After one month, the mother noticed an abnormal rotatory movements of the eyes with the development of postural instability for which she was again admitted and CSF studies done were within normal limits.
Differential diagnosis:
● Opsoclonus-myoclonus Ataxia
● Cerebellar dysfunction
● Residual Tumor
● Normal pressure hydrocephalus
● Vestibular dysfunction
Investigations:
TC: 10.51, N: 70, L: 19.8, E: 1, Hb: 8.2, Platelets: 438
OT/PT: 27/29
S.Creatinine: 0.5
S.Sodium: 134, S.K: 4.0
Lactate: 2.33mmol/L
fT4: 1.33
TSH: 4.95
USG Abdomen: Lesion in right suprarenal region
CT Abdomen: Right suprarenal mass
MIBG: Suprarenal neuroblastoma.
VEEG: No epileptiform abnormalities
Oligoclonal band in CSF : Not detected
CSF Culture: Sterile
CSF Cytology: No malignant cells
EEG was also within normal limits.
FISH for N-MYC AMPLIFICATION: Negative
Echo: Normal
The child has received three doses of IV Immunoglobulin, steroids and Rituximab in view of the possibility of opsoclonus-myoclonus ataxia syndrome post neuroblastoma. The child improved and discharged on oral steroids and she is kept under close follow-up on OPD basis.
USG Image of a neuroblastoma
DISCUSSION:
Opsoclonus-Myoclonus Syndrome (OMS), also known as “dancing eyes-dancing feet syndrome,” is a rare neurological disorder often associated with neuroblastoma, particularly in children. It is an autoimmune-mediated paraneoplastic syndrome where the immune response against the tumor inadvertently attacks the nervous system.
1. Opsoclonus
2. Myoclonus
3. Ataxia
4. Behavioral and Cognitive Changes
Pathophysiology:-
Autoimmune Response: OMS is believed to result from the body’s immune response to neuroblastoma. The immune system targets antigens present on the neuroblastoma cells, but these antigens are also present in the central nervous system, leading to neurological damage.
Neuroinflammation: Inflammation in the brain, particularly the cerebellum and brainstem, contributes to the symptoms.
Association with Neuroblastoma:
Paraneoplastic Syndrome: OMS occurs in about 2-3% of children with neuroblastoma. It can present before, during, or after the diagnosis of the tumor.
Prognosis: The presence of OMS can be associated with a more favorable outcome concerning the neuroblastoma itself, but it may lead to long-term neurological sequelae.
Diagnosis:
Clinical Diagnosis: Based on the characteristic symptoms of opsoclonus, myoclonus, and ataxia.
Neuroimaging: MRI may be used to rule out other causes of symptoms.
Tumor Workup: Scans to detect neuroblastoma, such as CT, MRI, or MIBG scan.
Cerebrospinal Fluid Analysis: May show pleocytosis (increased white cells) and oligoclonal bands.
Treatment:
1. Immunotherapy:
– Corticosteroids: Often the first line of treatment to reduce inflammation.
– Intravenous Immunoglobulin (IVIG)
– Rituximab
– Cyclophosphamide
2. Tumor Treatment:
– Surgery
– Chemotherapy/Radiation: Depending on the tumor stage.
3. Symptomatic Treatment:
– Physical Therapy
– Speech Therapy
– Behavioral Therapy
TAKE HOME MESSAGE: While some children recover fully, others may have persistent neurological issues, including motor, cognitive, and behavioral problems. It is necessary to monitor and manage potential relapses or late effects of treatment. Opsoclonus-Myoclonus Syndrome is a challenging condition requiring a multidisciplinary approach to treatment, addressing both the underlying neuroblastoma and the neurological symptoms.