Reflections on the brainstem dysfunction in neurologically disabled children

Gut dysmotility in children with neurological impairment: the nutritional management

Intestinal motility disorders represent a frequent problem in children with neurological impairment. These conditions are characterized by abnormal movements of the gut, which can result in symptoms such as constipation, diarrhea, reflux, and vomiting. The underlying mechanisms leading to dysmotility are various, and the clinical manifestations are often nonspecific. Nutritional management is an important aspect of care for children with gut dysmotility, as it can help to improve their quality of life. Oral feeding, when safe and in the absence of risk of ingestion or severe dysphagia, should always be encouraged. When oral nutrition is insufficient or potentially harmful, it is necessary to switch to an enteral by tube or parenteral nutrition before the onset of malnutrition. In most cases, children with severe gut dysmotility may require feeding via a permanent gastrostomy tube to ensure adequate nutrition and hydration. Drugs may be necessary to help manage gut dysmotility, such as laxatives, anticholinergics and prokinetic agents. Nutritional management of patients with neurological impairment often requires an individualized care plan to optimize growth and nutrition and to improve overall health outcomes. This review tries to sum up most significant neurogenetic and neurometabolic disorders associated with gut dysmotility that may require a specific multidisciplinary care, identifying a proposal of nutritional and medical management.

Brainstem hypoxic-ischemic lesions on MRI in infants treated with therapeutic cooling: effects on the length of stay and mortality

OBJECTIVE

To test the hypothesis that brainstem hypoxic-ischemic injury on magnetic resonance imaging (MRI) would be independently associated with short-term outcomes in cooled asphyxiated infants.

METHODS

A total of 90 consecutively cooled asphyxiated infants who survived to have brain MRI were reviewed. A neuroradiologist who was masked to outcomes evaluated MRI images for brainstem involvement. Outcomes were mortality and length of stay.

RESULTS

Brainstem lesions were present on post-cooling brain MRI in 20 of the 90 infants (22%). Overall, four infants died before discharge, and all four had brainstem involvement. The infants with brainstem involvement had longer hospital stay (29 days, IQR 20-47 versus 16 days, IQR 10-26; P = 0.0001), compared to infants without brainstem lesions (n = 70); and upon multivariate analysis, brainstem involvement remained independently associated with prolonged hospital stay (β = 12.4, P = 0.001).

CONCLUSION

This study demonstrates the importance of recognizing brainstem injury for the prediction of short-term outcomes in cooled asphyxiated infants.

Leigh Syndrome Caused by the MT-ND5 m.13513G>A Mutation: A Case Presenting with WPW-Like Conduction Defect, Cardiomyopathy, Hypertension and Hyponatraemia

Mitochondrial disease can present with a wide range of clinical phenotypes, and knowledge of the clinical spectrum of mitochondrial DNA mutation is constantly expanding. Leigh syndrome (LS) has been reported to be caused by the m.13513G>A mutation in the ND5 subunit of complex I (MT-ND5 m.13513G>A). We present a case of a 12-month-old infant initially diagnosed with tachyarrhythmia requiring defibrillation, subsequent presentation with hypertension and hyponatraemia secondary to renal salt loss and presumed inappropriate ADH secretion. Complex I activity in the muscle tissue was 54%, and mutation load in the muscle and lymphocytes was 50%. This case of Leigh syndrome caused by the m.13513G>A mutation in the ND5 gene illustrates that hyponatraemia due to renal sodium loss and inappropriate ADH secretion and hypertension can be features of this entity in addition to the previously reported cardiomyopathy and WPW-like conduction pattern and that they present additional challenges in diagnosis and management.

Brainstem tegmental necrosis and olivary hypoplasia: raising awareness of a rare neuropathologic correlate of congenital apnea

This case study describes an instance of death in an early term female newborn with congenital apnea in the clinical setting of multiple congenital anomalies (retrognathia, posteriorly rotated ears, camptodactyly, and arthrogryposis) and prenatal history of polyhydramnios. Postmortem neuropathologic findings were significant for tegmental necrosis in the caudal pons and medulla characterized by a coalescence of microcalcifications accompanied by neuronal loss, axonal spheroids, gliosis, and a concomitant hypoplasia of the inferior olives. This report raises awareness of the rare lethal entity of brainstem tegmental necrosis and olivary hypoplasia and its nosological relationship to the Möbius syndrome in the context of differential diagnosis of congenital apnea owing to central respiratory dysfunction.

Central and peripheral factors contributing to obstructive sleep apneas

Apnea, the cessation of breathing, is a common physiological and pathophysiological phenomenon. Among the different forms of apnea, obstructive sleep apnea (OSA) is clinically the most prominent manifestation. OSA is characterized by repetitive airway occlusions that are typically associated with peripheral airway obstructions. However, it would be an oversimplification to conclude that OSA is caused by peripheral obstructions. OSA is the result of a dynamic interplay between chemo- and mechanosensory reflexes, neuromodulation, behavioral state and the differential activation of the central respiratory network and its motor outputs. This interplay has numerous neuronal and cardiovascular consequences that are initially adaptive but in the long-term become major contributors to morbidity and mortality. Not only OSA, but also central apneas (CA) have multiple, and partly overlapping mechanisms. In OSA and CA the underlying mechanisms are neither "exclusively peripheral" nor "exclusively central" in origin. This review discusses the complex interplay of peripheral and central nervous components that characterizes the cessation of breathing.

Experience of using electromyography of the genioglossus in the investigation of paediatric dysphagia

AIM

The aim of the study was to assess, retrospectively, the utility of genioglossus electromyography (gEMG) in evaluating children with suspected neurogenic feeding and swallowing difficulties.

METHOD

Children who were evaluated using gEMG at a tertiary paediatric neurology dysphagia service were reviewed. Data were analysed by the presence/absence of neurogenic changes on gEMG and the method of feeding at their most recent follow-up.

RESULTS

The study group comprised 59 individuals (36 males, 23 females; median age 20 mo; range 1 mo-15 y). The study cohort included individuals with heterogeneous neurological phenotypes (n=40), craniofacial syndrome (n=10), and congenital bulbar palsy (n=9). gEMG identified 35 out of 59 (60%) with neurogenic changes. At follow-up, 24 individuals were on oral feeds and 35 were on alternative methods of feeding (nasogastric /gastrostomy). Eight out of 24 children on oral feeds showed neurogenic changes compared with 27 out of 35 on alternative feeds. χ(2) analysis of feeding method at follow-up and the presence or absence of neurogenic change on EMG was highly significant (p≤0.002). When confounding factors for alternative feeds were accounted for on univariate analysis, the neurogenic changes, severe gastro-oesophageal reflux disease, and respiratory comorbidities were statistically significant in predicting the alternative feeding, whereas growth failure and behavioural difficulties were not significant confounders. Moreover, multiple logistic regression analysis revealed that the neurogenic changes were independently predictive of an alternative method of feeding after adjusting for other confounders with an odds ratio of 29.6 (95% confidence interval 3.97-220; p<0.007).

CONCLUSION

gEMG is a valuable complementary tool in the evaluation of children with neurogenic dysphagia as the degree of severity is independently correlated with long-term feeding outcomes.

Feeding and communication impairments in infants with central grey matter lesions following perinatal hypoxic-ischaemic injury

BACKGROUND

Basal ganglia and thalamic (BGT) injury is common after acute perinatal hypoxia-ischaemia. Cerebral palsy is the most obvious consequence of BGT injury affecting 70-75% of survivors and is predictable from neonatal magnetic resonance imaging (MRI). However there is no equivalent predictive data for other specific outcomes. Feeding and communication impairments are also common in children following hypoxic-ischaemic encephalopathy (HIE) and BGT injury.

AIMS

To describe, in infants with HIE and BGT injury, the prevalence of feeding and communication impairments; and to evaluate the accuracy of early MRI for predicting these outcomes.

METHODS

175 term infants with HIE and BGT injury were studied. Brain lesions were classified by site and severity from the MRI scans. Motor, feeding and communication impairments were documented at 2 years.

RESULTS

Feeding and communication impairments occurred in 65% and 82% of 126 survivors respectively and related strongly to the severity of motor impairment. Forty-one children had a gastrostomy or long-term nasogastric tube. Injury severity in all brain regions was significantly associated with feeding and communication impairment on univariate analysis. On logistic regression analysis BGT (OR 10.9) and mesencephalic lesions (OR 3.7) were independently associated with feeding impairment; BGT (OR 10.5) and pontine lesions (OR 3.8) were associated with gastrostomy; the severity of BGT lesions (OR 20.1) was related to the severity of communication impairment.

CONCLUSIONS

Feeding and communication impairment are very common in children with BGT and brainstem injury of neonatal origin and can be well predicted from early MRI scans.

A case of bulbar type cerebral palsy: representative symptoms of dorsal brainstem syndrome

In this study, we present the case of a 2-year-old boy who exhibited facial and bulbar paralysis since birth, severe dysphagia, signs of oculomotor disturbance, jaw jerks, pyramidal signs on both toes, intellectual disability, and severe gastroesophageal reflux. His blink reflex and auditory/somatosensory evoked potentials suggested abnormalities in the lower brainstem, and magnetic resonance imaging showed a T2 hyperintense area in the pontine tegmentum. These findings combined with the patient's symptoms suggested "dorsal brainstem syndrome" and indicated a possibility of prenatal asphyxia in this patient. Nosologic issues regarding this subgroup of cerebral palsy are discussed here.

Central hypoventilation and brainstem dysgenesis

We report on a newborn with congenital hypotonia, unilateral facial palsy, sucking and swallowing difficulties, velopalatine incoordination, and unilateral impairment of the auditory brainstem responses, attributable to brainstem dysgenesis. On follow-up, the child manifested developmental delay and central hypoventilation syndrome during sleep. The ventilation abnormality during sleep with insensitivity to hypercapnia, associated with unilateral facial paralysis, indicates a pontine lesion, including the parafacial respiratory group.

Clinical practice: swallowing problems in cerebral palsy

Cerebral palsy (CP) is the most common physical disability in early childhood. The worldwide prevalence of CP is approximately 2-2.5 per 1,000 live births. It has been clinically defined as a group of motor, cognitive, and perceptive impairments secondary to a non-progressive defect or lesion of the developing brain. Children with CP can have swallowing problems with severe drooling as one of the consequences. Malnutrition and recurrent aspiration pneumonia can increase the risk of morbidity and mortality. Early attention should be given to dysphagia and excessive drooling and their substantial contribution to the burden of a child with CP and his/her family. This review displays the important functional and anatomical issues related to swallowing problems in children with CP based on relevant literature and expert opinion. Furthermore, based on our experience, we describe a plan for approach of investigation and treatment of swallowing problems in cerebral palsy.

Dorsal brain stem syndrome: MR imaging location of brain stem tegmental lesions in neonates with oral motor dysfunction

The anatomic extent of brain stem damage may provide information about clinical outcome and prognosis in children with hypoxic-ischemic encephalopathy and oral motor dysfunction. The aim of this study was to retrospectively characterize the location and extent of brain stem lesions in children with oral motor dysfunction. From January 2005 to August 2009, 43 infants hospitalized at our institution were included in the study because of a history of hypoxic-ischemic events. Of this group, 14 patients showed oral motor dysfunction and brain stem tegmental lesions detected at MR imaging. MR imaging showed hypoxic-ischemic lesions in supra- and infratentorial areas. Six of 14 patients revealed only infratentorial lesions. Focal symmetric lesions of the tegmental brain stem were always present. The lesions appeared hyperintense on T2-weighted images and hypointense on IR images. We found a strong association (P < .0001) between oral motor dysfunction and infratentorial lesions on MR imaging. Oral motor dysfunction was associated with brain stem tegmental lesions in posthypoxic-ischemic infants. The MR imaging examination should be directed to the brain stem, especially when a condition of prolonged gavage feeding is necessary in infants.