Role of imaging in the diagnosis of acute bacterial meningitis and its complications.

Acute bacterial meningitis is a common neurological emergency and a leading cause of death and neurological disability worldwide. Diagnosis is based on clinical and microbiological findings with neuroimaging in the form of CT reserved for those with specific adverse clinical features or when an underlying cause such as mastoiditis is suspected. MRI is extremely useful for detecting and monitoring the complications of meningitis. These can be remembered by the mnemonic HACTIVE (hydrocephalus, abscess, cerebritis/cranial nerve lesion, thrombosis, infarct, ventriculitis/vasculopathy and extra-axial collection). Diffusion weighted imaging (DWI) and magnetic resonance spectroscopy (MRS) are useful to distinguish abscess from other ring enhancing lesions.

False diagnosis of papilloedema and idiopathic intracranial hypertension.

The diagnosis of idiopathic intracranial hypertension (IIH) relies heavily on the appearance of the optic disc. We report eighteen children referred to us over a 3 year period with disc swelling and suspected IIH. Following a tertiary ophthalmological review, papilloedema was excluded in ten with buried drusen, disc crowding, pseudopapilloedema, or misinterpretation of normal appearances. In these ten children, five had a mean opening pressure on lumbar puncture of 27.2 cm H2O, range 19-32, which was significantly lower than those with IIH (37.5 cm H2O, range 29-47; p<0.01). We conclude that diagnosis of IIH is difficult, and that more precisely defined criteria for assessment and diagnosis are needed.

Retention rate of levetiracetam in children with intractable epilepsy at 1 year.

UNLABELLED: Levetiracetam (LEV) is a novel antiepileptic drug (AED) that has recently obtained marketing authorisation for use in children. The purpose of this study was to assess the efficacy, tolerability and retention rate of LEV in children with refractory epilepsies. It is a retrospective multicentre observational study reporting the use of LEV in 200 children, aged 0.3-19 years (median 9-years-old) over a 4-year period. All of the patients included in the study had refractory epilepsy with a median age of onset of epilepsy of 3 years (range 0-13 years). The 38% had failed and withdrawn 3 or more AEDs previously and 24% were taking at least 2 other AEDs in addition to LEV. The 47% had focal, and 58% had symptomatic epilepsies. The LEV dose ranged from 8 to 100 mg/kg/day (mean 39 mg/kg). The study comprised 215 person years of LEV exposure. RESULTS: LEV was well tolerated with a retention rate of 49% at 1 year. No serious adverse events were reported with possibly related adverse events reported in only 24% of patients (mainly emotional or behavioural changes). At more than 2, 6 and 12 months, worthwhile improvement (>50% seizure reduction) was noted in 60, 40 and 32%, including seizure freedom in 14, 14 and 5%, respectively. CONCLUSION: Our results confirm the efficacy and tolerability of LEV in children with refractory epilepsies and demonstrate good response and retention rates at 12 months. It represents the largest cohort of paediatric patients published so far on LEV with a 1-year follow-up.

The significance of reduced respiratory chain enzyme activities: clinical, biochemical and radiological associations.

BACKGROUND: Mitochondrial diseases are an important group of neurometabolic disorders in children with varied clinical presentations and diagnosis that can be difficult to confirm. AIM: To report the significance of reduced respiratory chain enzyme (RCE) activity in muscle biopsy samples from children. METHODS: Retrospective odds ratio was used to compare clinical and biochemical features, DNA studies, neuroimaging, and muscle biopsies in 18 children with and 48 without reduced RCE activity. RESULTS: Children with reduced RCE activity were significantly more likely to have consanguineous parents, to present with acute encephalopathy and lactic acidaemia and/or within the first year of life; to have an axonal neuropathy, CSF lactate >4 mmol/l; and/or to have signal change in the basal ganglia. There were positive associations with a maternal family history of possible mitochondrial cytopathy; a presentation with failure to thrive and lactic acidaemia, ragged red fibres, reduced fibroblast fatty acid oxidation and with an abnormal allopurinol loading test. There was no association with ophthalmic abnormalities, deafness, epilepsy or myopathy. CONCLUSION: The association of these clinical, biochemical and radiological features with reduced RCE activity suggests a possible causative link.

Paediatric post-septal and pre-septal cellulitis: 10 years' experience at a tertiary-level children's hospital.

OBJECTIVE: To assess the incidence and complications of pre-septal (pre-SC) and post-septal (post-SC) cellulitis over 10 years. Pre-SC and post-SC are also known as periorbital and orbital cellulitis, respectively. METHODS: Retrospective analysis of CT scans. Data included the presence of pre-SC and post-SC, paranasal sinus disease (PNS) and complications. RESULTS: Among 125 patients scanned for these suspected diagnoses, 67 had both pre-SC and post-SC, 37 had pre-SC and 4 had post-SC; there were 17 normal scans. 110 patients had PNS. 68/71 (96%) patients with post-SC had PNS. Post-SC complications included orbital and/or subperiosteal abscess (50/71: 30 medial orbital, 10 superomedial, 3 lateral, 2 anteromedial, 2 inferomedial, 1 superior, 1 anterosuperior and 1 not specified), cavernous sinus thrombosis (CST) (1), superior ophthalmic vein (SOV) thrombosis (4) and subdural frontal empyema (2); 1 patient had SOV and CST and subdural empyema. CONCLUSION: 71/125 (57%) patients had post-SC. 50/125 (40%) patients imaged for pre-SC/post-SC had orbital abscess; 44/50 (88%) of these involved the medial orbit. Patients can develop solely superior or inferior abscesses that are difficult to identify by axial imaging alone, hence coronal reformatted imaging is essential. 5/125 (4%) patients developed major complications (SOV/CST/empyema), hence imaging review of the head and cavernous sinus region is essential. A diagnosis of post-SC on CT should alert the radiologist because this diagnosis can be associated with an increased incidence (5/71, 7%) of complications. ADVANCES IN KNOWLEDGE: We recommend that all patients with a suspected diagnosis of post-SC should undergo CT scan (post-contrast orbits and post-contrast head, with multiplanar reformats and a careful review of the SOV and the cavernous sinus). Particular attention should be paid to exclude intracranial complications including subdural empyema and cerebral abscess. As soon as a diagnosis of post-SC is made, in addition to informing the referring clinical team, urgent opinion should be sought from ear, nose and throat (ENT), neurology and ophthalmology with a view to urgently drain of the paranasal sinuses`.

Retention rate of Gabapentin in children with intractable epilepsies at 1 year.

Gabapentin (GAB) is a newer second-line antiepileptic drug (AED) used in children. This is a multi-centre retrospective observational study of the efficacy, tolerability and retention rate in 105 children, aged 0-17.5 years (mean 10.1) over a 14 year period. The median age of epilepsy onset was 2.5 years (range 0-14.6). 72% started GAB as at least the 3rd AED, with 43% having been withdrawn from at least 2 AEDs. 77% had focal and 52% symptomatic epilepsies. The maintenance doses for GAB ranged 6.0-87.3 mg/kg/day (mean 43.7). The study comprised 157 person-treatment years for GAB. GAB was well tolerated with 55% remaining on treatment beyond 1 year. No serious adverse events were reported whilst on GAB, but 39% reported possibly and probably related adverse events. Seizure improvement (<50% seizure frequency compared to baseline) at more than 12 months of treatment, was reported in 35% of patients starting GAB, including 6% who remained seizure free. The results demonstrated the efficacy and tolerability of GAB in children with difficult to treat epilepsies, and a good response to treatment beyond 12 months, in both focal and generalised epilepsies.

Clinical report: AN INTERSTITIAL deletion of 16p13.11 detected by array CGH in a patient with infantile spasms.

Chromosome 16p13.11 has recently been reported as a region of recurrent microdeletion/duplication, which may contribute to a specific clinical phenotype of epilepsy, significant learning difficulties and distinct facial dysmorphism. The 16p13.11 microdeletion syndrome is associated with schizophrenia, developmental delay and idiopathic generalised epilepsy. Haploinsufficiency of genes in 16p13.11 has been suggested as contributing to the pathogenicity of this microdeletion syndrome. We report a three-year-old boy with the 16p13.11 microdeletion syndrome, identified on array CGH, and describe his clinical phenotype, thereby adding to the existing literature on this newly-described microdeletion syndrome. We discuss the function and potential relevance of the genes in this region with regards to the features described in this condition.

The encephalopathic child.

Encephalopathy is a common paediatric emergency associated with a high risk of morbidity, mortality and long term neurodevelopmental delay in survivors. Prompt diagnosis of the cause of encephalopathy enables the paediatrician to deliver specific medical or surgical treatment that will facilitate a better short and long term outcome. Diagnostic imaging plays a pivotal role in diagnosis. Encephalopathy has many causes. The differential diagnosis includes non accidental injury, trauma, metabolic syndromes, meningo-encephalitis, toxins, hypoxia, demyelination, stroke, haemorrhage and tumours. We describe an approach that helps us formulate an imaging strategy using US, CT and MRI that facilitates patient care.

Occult carotid pseudoaneurysm following streptococcal throat infection.

Pseudoaneurysm of the internal carotid artery (PAICA) is a rare complication of neck space infection. An 8-year-old girl presented with odynophagia (painful swallowing), trismus and left peritonsillar swelling. Abscess was suspected, but aspiration was dry. The PAICA was diagnosed on computed tomography. The aneurysm and involved left internal carotid artery were occluded endovascularly. She has made an uneventful recovery.

Child psychiatry training for paediatric neurology trainees; a personal view.

The authors describe their experience to support the view that training in child psychiatry is an effective way for the paediatrician in training to gain an understanding of that specialty. It is also an efficient way to acquire certain skills, which will be helpful in the future, either in hospital or community paediatrics.

'Cerebral palsy' due to mitochondrial cytopathy.

Two children aged 10 and 13 years with initially static motor problems, diagnosed as cerebral palsy, were found to have respiratory chain defects after developing a progressive course and multisystem involvement. Mitochondrial cytopathies should be considered in the differential diagnosis of cerebral palsy.