A 28-month-old girl has recently become irritable and “clingy” with difficulty sleeping and occasional high-pitched crying. Her mother reports that her speech has decreased and she is clumsier. Can you venture a diagnosis?
Background
A 28-month-old girl has recently become irritable and “clingy” with difficulty sleeping and occasional high-pitched crying. Her mother reports that her speech has decreased and she is clumsier. The girl also complains of “ouchy” and points to her navel but is not constipated.
She is an only child born by normal vaginal delivery at full term, and she has met the normal developmental milestones until recently. Her immunizations are up to date. Her symptoms started a month ago when her grandmother relocated to a different state. Her pediatrician suspected that her symptoms resulted from the anxiety of losing contact with “nana” and reassured her mother that she should “watch and wait.” However, the child grew increasingly unsteady when she walked, to the point of losing her balance and falling over, and her eyes developed intermittent chaotic and jerky movements. The mother was alarmed and contacted the pediatrician, who directed her to the emergency department.
The mother and child live in an older part of Philadelphia. The only significant illness recorded for the child is an episode of iron deficiency anemia at the age of 12 months when the child was drinking four bottles of cow’s milk a day, eating dirt, and chewing on the doorframe. Laboratory testing confirmed she had microcytic hypochromic anemia and a profoundly low ferritin level that resolved with dietary counseling and a therapeutic course of ferrous sulfate. She has had the usual childhood coughs, colds, and mild viral illnesses, including a “strep throat” infection, but she has not had any such illnesses during the previous 2 months. She has no history of weight loss, fever, headache, rashes, joint swelling, pallor, or bruising.
Physical Examination and Workup
Upon examination, the patient is alert but irritable and difficult to console. Her vital signs are normal, including a heart rate of 108 beats/minute, a respiration rate of 28 breaths/minute, and a blood pressure of 96/58 mm Hg. Her oxygen saturation is 98% on room air. She is afebrile. No pallor, icterus, lymphadenopathy, cyanosis, clubbing, or rashes are noted. Results of the neurologic examination are remarkable for intermittent jerking movements of her arms and legs, with an unsteady ataxic gait. Her pupils are equal and react to light, and other cranial nerves appear intact. However, she has intermittent conjugate jerky eye movements that are not confined to a particular direction.
Power and tone are difficult to assess, but deep tendon reflexes are present and symmetrical, with downgoing plantar responses and no meningeal signs. Her chest is clear to auscultation. The cardiovascular examination reveals normal first and second heart sounds, with a low-pitched grade 2/6 systolic murmur at the left lower sternal border. Her abdomen is soft and nontender with no hepatosplenomegaly and no palpable masses.
Initial test results include a complete blood cell count that is notable for a hemoglobin level of 11.2 g/dL (reference range, 12.6-17.4 g/dL); normal total white blood cell count, differential, and platelet counts; and a peripheral blood smear that shows no abnormalities. Serum electrolyte, creatinine, and liver enzyme levels are within the normal range. The results of a routine urine examination are normal, and the urine vanillylmandelic acid (VMA) level is also in the normal range.
See video examples of these behaviours here.
An abdominal ultrasound scan shows no abnormal masses. A CT scan of the brain with and without contrast reveals no evidence of a tumor, hydrocephalus, or intracranial bleeding. The findings of a lumbar puncture are:
- Appearance of cerebrospinal fluid (CSF): Clear
- Pressure: Normal
- White blood cell count: 3 cells/µL, all lymphocytes (reference range, 0-5 cells/µL [< 2 polymorphonucleocytes])
- Protein and glucose levels: Normal
- An MRI scan of the brain with contrast shows no evidence of a space-occupying lesion; a formal report is pending.
Based only on these findings, which of the following is the most likely diagnosis? Below are some options and the answers from previous respondents.
- Lead-related neurotoxicity (56%)
- Sydenham (rheumatic) chorea (7%)
- Postviral cerebellar ataxia (14%)
- Opsoclonus-myoclonus ataxia syndrome (23%)
The correct answer is opsoclonus-myoclonus ataxia syndrome.
Discussion
Acute ataxia is a rare finding in a toddler. In this case, the prodrome of behavioral changes, the association with myoclonic jerks, and the presence of intermittent rapid, conjugate, multidirectional eye movements (opsoclonus) helped establish the diagnosis of opsoclonus-myoclonus ataxia syndrome (OMAS), also known as “dancing eyes and dancing feet syndrome.” OMAS primarily affects toddlers and is commonly associated with the presence of a neuroblastoma. Of the 650 children who receive a diagnosis of neuroblastoma each year in North America, 2%-4% have OMAS. In 2004, an international task force recommended that three of these four criteria be present to diagnose neuroblastoma with OMAS:
- Opsoclonus
- Myoclonus and ataxia
- Behavioral change and/or sleep disturbance
- Neuroblastoma
All the classic findings of OMAS do not need to be present to make a diagnosis, so OMAS should be considered in any toddler or preschool child who has unexplained ataxia of sudden onset. In the patient in this case, a whole body MRI scan showed a 2.6 × 2.2 × 1.1-cm tumor in the left paravertebral area at the level of D9.
For more information
See the full article: Decreased Speech and Jerky Eye Movements in a ‘Clumsy’ Toddler (medscape.com)
Authors: Vikramjit Kanwar, MBBS, MBA; Shyam Srinivasan, MBBS, DM
All content from this article belongs to Medscape.com