Neonatal hypertonia - a diagnostic challenge.

In comparison to hypotonia, hypertonia is less commonly expressed in the neonatal period. The scientific literature on the causes of neonatal hypertonia is scant, with no suggested diagnostic algorithm easily available to clinicians. Aetiologies include conditions affecting the central nervous system and spine, and rare peripheral neuromuscular disorders leading to hypertonia. Aetiology onset may be antepartum, peripartum with either transient hypertonia or persistent hypertonia which may appear later, or from a postnatal event/disease. This review discusses neonatal hypertonia and a diagnostic approach to neonatal hypertonia is suggested.

Mutations in genes encoding ribonuclease H2 subunits cause Aicardi-Goutières syndrome and mimic congenital viral brain infection.

Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation.

Outcome of children with hyperventilation-induced high-amplitude rhythmic slow activity with altered awareness.

Hyperventilation-induced high-amplitude rhythmic slow activity with altered awareness (HIHARS) is increasingly being identified in children and is thought to be an age-related non-epileptic electrographic phenomenon. We retrospectively investigated the clinical outcome in 15 children (six males, nine females) with HIHARS (mean age 7y, SD 1y 11mo; range 4y 6mo-11y). The presenting feature in 11 cases was blank spells - two of these children also had generalized tonic-clonic seizures (GTCS) - and in one individual the main concern was deteriorating school performance. Three children had symptoms suggestive of focal motor seizures. Of the nine children presenting solely with blank spells, further follow-up (mean duration 18mo, SD 21mo) revealed full resolution of symptoms in six, but three had persistent symptoms. In our study, the symptoms of children with HIHARS presenting with blank spells in isolation appeared to resolve spontaneously and did not evolve into convulsive seizures or other paroxysmal events considered to be clearly epileptic. Children (with HIHARS) who presented with clinical features suggestive of GTCS or focal motor seizures (with or without blank spells) and/or had epileptiform discharges on interictal electroencephalography were subsequently diagnosed with epilepsy.

Movement disorders associated with complex regional pain syndrome in children.

The aim of the present study was to review the history, clinical course, treatment, and outcome of movement disorders in children and young people with complex regional pain syndrome (CRPS). Case notes were reviewed retrospectively of children and young people who presented with movement disorders in CRPS to our tertiary paediatric pain service over a period of 13 years. Ten children with CRPS presented with movement disorders (eight females, two males). The age at first presentation with symptoms of CRPS ranged from 8 to 15 years (mean 11 y 2 mo, median 13 y). The most common movement disorder was dystonia (n=8), followed by tremors (n=3) and myoclonus (n=3); two patients had all three movement disorders. The movement disorder affected mainly the lower limb (n=9) with a predilection for the foot (n=7) and was frequently initiated by minor trauma (n=7). Follow-up ranged from 6 months to 14 years. The outcome was variable, with good prognosis in nearly half of the cases: four children experienced complete resolution of symptoms. Two children showed a slight improvement. Four children showed no improvement. Movement disorders in CRPS are under-recognized in children. The management has to be multidisciplinary with an expertise in paediatric pain.

Skull base osteomyelitis leading to lateral medullary syndrome in a child.

Skull base osteomyelitis (SBO) arising from the sphenoidal paranasal air sinus infection without associated external otitis is rare. Initially SBO may have headache as the only symptom with cranial neuropathies occurring later. We report a 10-year-old immunocompetent girl with headache and chronic sinusitis, who developed a lateral medullary syndrome following streptococcal milleri sphenoidal osteomyelitis.

Reversible parainfectious bilateral "striatal necrosis".

Bilateral striatal necrosis is usually associated with either endogenous or exogenous toxins, and with poor neurodevelopmental outcomes. We describe two patients with acute bilateral striatal clinical syndrome and magnetic resonance signal changes who made a complete clinical and radiologic recovery within 3 months. After an uneventful pregnancy, normal birth, and normal development, both boys presented at ages 3 and 5 years, respectively, after a viral illness with slurring of speech, bradykinesia, and an extrapyramidal movement disorder. On examination, both manifested bilateral cog wheel rigidity, with a broad-based gait and flexor plantar response. Cranial magnetic resonance imaging in both children indicated bilateral, symmetric, high signal changes in the lentiform nucleus, predominately in the putamen, with sparing of the globus pallidi bilaterally. The brain parenchyma was otherwise normal. Neurometabolic investigations produced normal results in both patients. The pathogenesis is uncertain, but could be immune-mediated. Both children, at 3-year and 1-year follow-ups, respectively, are doing well neurologically and academically. Our patients demonstrate that abnormal imaging findings during acute stages do not preclude good clinical and radiologic recovery.