Encefalopatía  neonatal 

24 -  Junio - 2017

 

 

Box 1 .- Features to look out for in history and examination

 

Pregnancy / labour history:

  • Was there an acute event occurring around the time of birth, such as non-reassuring or abnormal trace on cardiotocograph,99 antepartum haemorrhage, placenta previa, cord prolapse?

  • Fetal growth on antenatal scans

  • Fetal abnormalities on ultrasound scan or antenatal MRI

  • Was this a multiple pregnancy (twins, triplets, etc)?

  • Maternal infections or carriage of group B Streptococcus

  • Maternal hypertension

  • Pre-eclampsia

  • HELLP syndrome, particularly if associated with acute fatty liver infiltration, may indicate long chain 3 hydroxyacyl-coenzyme A dehydrogenase (LCHAD) deficiency2

  • Maternal hypotension

  • Maternal prescribed drug use

  • Maternal illicit drug use, particularly cocaine

  • Illness during pregnancy, such as may occur in viral infections that may affect the fetus

  • Gestational diabetes

  • Trauma, such as accidental falls or road traffic accident, and inflicted (assault)

  • Evidence of maternal haemorrhage

  • Any predisposing features to a non-accidental injury of baby, if presenting following normal period of consciousness?

Maternal past medical history:

  • Multiple miscarriages, stillbirths or neonatal deaths—consider genetic, thrombophilia and metabolic causes

  • Diabetes: associated with brain injuries, such as fetal thrombotic vasculopathy and postnatal hypoglycaemia

  • Deep vein thrombosis or other clotting disorders: suggestive of thrombophilia or clotting disorder and classical homocystinuria

  • Arterial ischaemic stroke: suggestive of thrombophilia or vascular abnormalities, such as COL4A1 gene mutations

  • Learning difficulties: suggestive of genetic/metabolic disorder, including myotonic dystrophy which may lead to secondary hypoxic brain injury

  • ‘Family history of cerebral palsy’: suggestive of vascular abnormalities, such as COL4A1 gene mutations, or thrombophilia

  • Cataracts: may indicate inborn error of metabolism, myotonic dystrophy, COL4A1 mutations

  • Stiffness or startling: consider myotonic disorders or hyperekplexia

  • Weakness or muscle fatigue: consider neuromuscular problem like myasthenia gravis or congenital myaesthenic syndrome, especially if phthalmoplegia or unexplained squint present. If muscle aches, pains and tetany exist, consider maternal hyperparathyroidism

  • Features of autoimmune disorder: involvement of several endocrine abnormalities, rash or other skin abnormalities like Raynaud’s syndrome, eye and kidney abnormalities, muscle aches and pains, heart block

  • Distal weakness of hands or feet, or abnormally shaped toes: consider peripheral neuropathy

Examination of the parents

  • This is important where a neuromuscular disorder is suspected.

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  • Neuropathies—reduced strength distally, suppressed or absent reflexes, abnormally shaped feet/toes, possible loss of sensation in either parent

  • Myopathies—proximal weakness, reduced reflexes and normal sensation in either parent

  • Neuromuscular junction defects like maternal myasthenia gravis or myaesthenic syndromes—fatigue/weakness on repeated or prolonged testing of grip strength, upward eye gaze or ptosis

  • Maternal myotonia in congenital myotonic dystrophy.

Neonatal examination

  • Head circumference abnormalities

  • Dysmorphic features

  • Abnormal fontanelle shape or size

  • Features suggestive of a metabolic condition (box 2)2

  • Rashes suggestive of immune, metabolic conditions or clotting disorders Family History of cerebral palsy:

  • External and internal ophthalmoplegia

  • Facial weakness

  • Features of peripheral involvement, with weakness and reduced reflexes

  • Features of spinal involvement—difficult vaginal birth, mixed upper and lower motor neuron finding, sensory level, urinary retention, constipation

  • Neonatal hypertonia—while neonates with hypoxic-ischaemic encephalopathy can exhibit hypertonia, tremor, myoclonus and shivering following birth, especially during hypothermia treatment, these usually resolve. A baby who is hypertonic from birth and remains stiff is unlikely to have experienced hypoxic-ischaemic encephalopathy. An approach to the diagnostic evaluation of hypertonic neonates has been proposed previously.2a