Loss of UGP2 in brain leads to a severe epileptic encephalopathy, emphasizing that bi-allelic isoform-specific start-loss mutations of essential genes can cause genetic diseases.

Developmental and/or epileptic encephalopathies (DEEs) are a group of devastating genetic disorders, resulting in early-onset, therapy-resistant seizures and developmental delay. Here we report on 22 individuals from 15 families presenting with a severe form of intractable epilepsy, severe developmental delay, progressive microcephaly, visual disturbance and similar minor dysmorphisms. Whole exome sequencing identified a recurrent, homozygous variant (chr2:64083454A > G) in the essential UDP-glucose pyrophosphorylase (UGP2) gene in all probands. This rare variant results in a tolerable Met12Val missense change of the longer UGP2 protein isoform but causes a disruption of the start codon of the shorter isoform, which is predominant in brain. We show that the absence of the shorter isoform leads to a reduction of functional UGP2 enzyme in neural stem cells, leading to altered glycogen metabolism, upregulated unfolded protein response and premature neuronal differentiation, as modeled during pluripotent stem cell differentiation in vitro. In contrast, the complete lack of all UGP2 isoforms leads to differentiation defects in multiple lineages in human cells. Reduced expression of Ugp2a/Ugp2b in vivo in zebrafish mimics visual disturbance and mutant animals show a behavioral phenotype. Our study identifies a recurrent start codon mutation in UGP2 as a cause of a novel autosomal recessive DEE syndrome. Importantly, it also shows that isoform-specific start-loss mutations causing expression loss of a tissue-relevant isoform of an essential protein can cause a genetic disease, even when an organism-wide protein absence is incompatible with life. We provide additional examples where a similar disease mechanism applies.

Rituximab Treatment in Myasthaenia Gravis: Report of two paediatric cases.

Myasthaenia gravis (MG) is an auto-immune disease involving the postsynaptic receptors in the neuromuscular junction. The condition is characterised by fatigable weakness of the skeletal muscles and is uncommon in children. Acetylcholinesterase inhibitors and immune-modifying medications are usually considered the mainstay of treatment. However, these medications have to be given on a lifelong basis so that patients remain in remission; furthermore, drug-related side-effects can have a major impact on quality of life. We report two paediatric cases who were treated for MG at the Sultan Qaboos University Hospital, Muscat, Oman, in 2007 and 2008, respectively. Rituximab was eventually administered to each patient after their condition failed to improve despite several years of standard treatment with acetylcholinesterase inhibitors and immune-modifying medications. Overall, rituximab resulted in complete remission in one case and significant clinical improvement in the other case.

Blood Culture Contaminants in a Paediatric Population Retrospective study from a tertiary hospital in Oman.

OBJECTIVES: Most children presenting with febrile illness require a blood culture to determine the causative organism as well as its sensitivity to antibiotics. However, false-positive results lead to unnecessary hospitalisations, prescriptions and tests. This study aimed to evaluate the impact of false-positive blood cultures among a paediatric population at a tertiary hospital in Oman. METHODS: This retrospective study included all 225 children <13 years old with positive blood cultures who presented to the Sultan Qaboos University Hospital, Muscat, Oman, between July 2011 and December 2013. Blood cultures were reviewed to determine whether they were true-positive or contaminated. RESULTS: A total of 344 positive blood cultures were recorded during the study period, of which 185 (53.8%) were true-positive and 159 (46.2%) were contaminated. Most true-positive isolates (26.5%) were coagulase-negative Staphylococcus spp. (CONS) followed by Escherichia coli (9.7%), while the majority of contaminated isolates were CONS (67.9%) followed by Streptococcus spp. (6.9%). Children with contaminated cultures were significantly younger (P <0.001) while those with true-positive cultures required significantly more frequent hospital admissions, longer hospital stays and more frequent antibiotic prescriptions (P <0.001 each). Chronic illness and mortality was significantly more frequent among those with true-positive cultures (P <0.001 and 0.04, respectively). While white blood cell and absolute neutrophil counts were significantly higher in true-positive cultures (P <0.001 each), there was no significant difference in C-reactive protein (CRP) level (P = 0.791). CONCLUSION: In this population, CRP level was not an adequate marker to differentiate between true- and false-positive cultures. A dedicated well-trained phlebotomy team for paediatric patients is essential.

Longitudinal extensive transverse myelitis (LETM) in children: A twenty-year study from Oman.

OBJECTIVE: The data on children with diagnosis of idiopathic transverse myelitis (ITM) was searched to find the pattern of myelitis in Oman. METHODS: A retrospective study was carried out from January1995 to December 2014. Electronic medical records and patient medical files were seen to get the complete data of the children with ITM. This work was carried out at Sultan Qaboos University hospital, Muscat, Oman. The ethical committee of the hospital had approved the study. The diagnosis was based on the established criteria. Other causes of myelopathy were excluded. RESULTS: 19 children with idiopathic transverse myelitis were found. There were 18 out of 19 (94.6%) children with longitudinal extensive transverse myelitis (LETM). CONCLUSION: Longitudinal transverse extensive myelitis is the most common form of ITM in Oman.

Rigid Spine Syndrome among Children in Oman.

OBJECTIVES: Rigidity of the spine is common in adults but is rarely observed in children. The aim of this study was to report on rigid spine syndrome (RSS) among children in Oman. METHODS: Data on children diagnosed with RSS were collected consecutively at presentation between 1996 and 2014 at the Sultan Qaboos University Hospital (SQUH) in Muscat, Oman. A diagnosis of RSS was based on the patient's history, clinical examination, biochemical investigations, electrophysiological findings, neuro-imaging and muscle biopsy. Atrophy of the paraspinal muscles, particularly the erector spinae, was the diagnostic feature; this was noted using magnetic resonance imaging of the spine. Children with disease onset in the paraspinal muscles were labelled as having primary RSS or rigid spinal muscular dystrophy. Secondary RSS was classified as RSS due to the late involvement of other muscle diseases. RESULTS: Over the 18-year period, 12 children were included in the study, with a male-to-female ratio of 9:3. A total of 10 children were found to have primary RSS or rigid spinal muscular dystrophy syndrome while two had secondary RSS. Onset of the disease ranged from birth to 18 months of age. A family history was noted, with two siblings from one family and three siblings from another (n = 5). On examination, children with primary RSS had typical features of severe spine rigidity at onset, with the rest of the neurological examination being normal. CONCLUSION: RSS is a rare disease with only 12 reported cases found at SQUH during the study period. Cases of primary RSS should be differentiated from the secondary type.

Eating epilepsy or feeding epilepsy in an infant.

A five month old infant is reported with Eating Epilepsy (feeding epilepsy/feeding related epilepsy). This is an uncommon type of reflex epilepsy in children, and should be considered if the history and investigations for gastro esophageal reflux and apparent life threatening event are negative. A clear stepwise history helps in diagnosis.

One in three: congenital bent bone disease and intermittent hyperthermia in three siblings with stuve-wiedemann syndrome.

Stuve-Wiedemann syndrome (STWS) is a rare disorder characterised by congenital bowing of the long bones, contractures of the joints, neonatal onset of respiratory distress, sucking and swallowing difficulties, dysautonomia presenting as episodic hyperthermia, and usually an early death. Three siblings from a consanguineous marriage presented with similar clinical features over 16 years. STWS was established with their last child at the beginning of 2012. All the children exhibited the onset of STWS in the neonatal period with fever and generalised hypotonia. Examinations of all the infants revealed camptodactyly, micrognathia, bent long bones with wide metaphyses, and hypotonia. Only the second affected child had myotonia, demonstrated by electromyography. Unusual pyrexia as a presenting feature in this syndrome needs early recognition so that extensive and elaborate investigations can be avoided. The disorder is usually caused by a mutation in the leukaemia inhibitory factor receptor gene.

Evolution of Ohtahara syndrome to continuous spikes and waves during slow sleep in an infant.

Encephalopathy with electrical status epilepticus in sleep (ESES) is defined as an age-related and self-limited electroclinical syndrome whose etiology is unknown and characterized by continuous spikes and waves during slow sleep (CSWS). Typical CSWS starts at an age of 4 to 5 years and ends by an average of 11 years. We report on an unexpected finding of CSWS in an 18-month-old male whose previous EEG at age 45 days was grossly abnormal with the presence of a burst suppression pattern during wakefulness and sleep. The patient had clinical seizures beginning day 1 of life leading to the suspicion of Ohtahara syndrome (the earliest form of epileptic encephalopathy). Patients with ESES usually have normal EEGs and functional development prior to the onset of CSWS pattern. To our knowledge, this presentation of a neonate with a history of neonatal seizures and developmental delay with an evolution to CSWS has not been described. A sleep record is strongly advised in children with epilepsy (despite the recording of awake EEG abnormalities), especially in patients with behavior or cognitive regression, to rule out the presence of CSWS.