A 6-year-old boy presented to our paediatric assessment unit for evaluation of persistent mutism following a hospital visit for routine venepuncture. He had been non-verbal for a few weeks and had begun using an iPad "talking board", at which he pointed to pictures and words. Due to this persistent mutism he had stopped attending school and it became clear there had been a sudden behavioural change.
He was born at term following an uneventful pregnancy to a single mother with mental health disorder. He has two younger brothers who have no history of developmental disorder. Prior to this presentation, he maintained a weight and height above the 25th centile. Apart from language delay he met his early developmental milestones. He attended nursery from age three and was assessed by age five for possible autism by the local child and adolescent mental health service (CAMHS). Although some of his behaviours appeared autistic in nature he did not meet the diagnostic threshold for ASD as he was functioning comparatively well in his first year of school.
Six months after the earlier presentation with mutism, he was found lying on the floor, still and unresponsive with no clear trigger identified. Further episodes occurred and each lasted between a few minutes and two hours. During these episodes he would not speak, move, or respond to vocal or touch stimuli. These episodes would end as abruptly as they started with him sitting bolt upright, being reactive, and crying. Subsequently, these catatonic episodes became more frequent and prolonged, lasting between ten and 48 hours. His weight dropped from the 25th centile to the 0.4th centile. This required admission to the local paediatric ward and a nasogastric tube (NGT) was inserted for nutrition and fluids. There was an initial difficulty in establishing a feeding regime, as he would frequently vomit. Eventually, a slow overnight feed was sufficiently tolerated. Whilst on the paediatric ward any catatonic episodes were preceded by extreme agitation, usually prior to a procedure such as passage of a NGT or venepuncture, and when ward staff attempted to restrain him he would suddenly become limp and unresponsive. He was also observed to lick and sniff ward staff that he liked and would frequently remove his NGT and offer it to staff as a gift. He became a significant flight risk with no sense of danger, requiring a wheelchair with restraining straps to attend appointments with his mother.
He was assessed by the paediatric neurologist and had extensive neuro-metabolic blood investigations, an electroencephalogram (EEG), and magnetic resonance imaging (MRI) of his brain (Figure 1). These were essentially normal. He was trialled on lorazepam with a good response and an immediate reversal of his catatonia. Nevertheless, catatonic episodes continued in the absence of lorazepam and he was therefore transferred to the National Child Psychiatric Inpatient Unit (NCPIU) for five weeks for further assessment outside of his normal environment. He was commenced on regular lorazepam and his clinical condition improved significantly, with no further catatonic episodes during this admission. He was diagnosed with ASD with co-morbid catatonia because, now aged 7, he had been withdrawn from school by his mother and his social communication skills had regressed to the point he now satisfied the DSM 5 criteria for a diagnosis of ASD. Autistic symptoms (though not satisfying the DSM 5 criteria) had been present for two years prior to the development of catatonia.
On discharge from the NCIPU he struggled with transition to life at home. He developed stress-related alopecia and the frequency of catatonic episodes increased significantly. Atomoxetine was commenced following a diagnosis of co-morbid attention deficit hyperactivity disorder (ADHD). This was diagnosed on the basis of the DSM 5 criteria; he displayed a persistent pattern of inattention and hyperactivity-impulsivity that interfered with his functioning and development. Atomoxetine was soon stopped, however, due to nausea and vomiting. The lorazepam was increased to a maximum of 12 mg (0.54 mg/kg) daily which resolved his catatonic episodes. Guanfacine was commenced but soon withdrawn as the patient refused to swallow it. Methylphenidate was started and has been titrated to 15 mg twice daily which has been effective (decreasing emotional outbursts, increasing creative play and ability to self-soothe) and well tolerated with no adverse effects. Lorazepam 12 mg daily was well tolerated with no adverse effects. It has since been decreased to dose of 8 mg daily with plans to wean further.