No one saw anything wrong with Tom.
Born naturally with his twin brother in April 2001, he hit his milestones – crawling, walking, talking – within a month of his brother.
So how can it be that I am now caring for a 20-year-old diagnosed with autism and a moderate intellectual disability, who will never live independently, while his twin studies economics at Trinity?
How did this happen?
I imagined it! I was too busy with those twins – and another two children on top of them – to notice that Tom was born disabled. I imagined his sudden, terrifying eruption at the age of 4½, and the catastrophic deterioration of his functioning thereafter.
My memories are not to be trusted.
I nearly believed this myself.
Until once again, at Christmas, we got out the old family videos and somehow managed to make them playable on today’s equipment. There was the young Tom with his butter-blonde bob, living in the here and now instead of the faraway world in which he now lives. He and his brother were playing companionably with their two stuffed dogs, Judge and Wow-wow.
I sat on my blue chair that night and started to Google: “Autism: regression at 4½.”
Why yes, said Dr Google. Your child has childhood disintegrative disorder.
CDD was first diagnosed as Heller’s syndrome in 1908, but “disintegrative disorder” is a phrase which perfectly encapsulates what happened to Tom.
I remember telling a plethora of mental health professionals that it was as if Tom had been thrown up in the air and all the bits of him had landed in a jumble.
Rolls of eyes. I had done this to my child. I needed a psychotherapist.
I remember telling a social worker that what had happened to Tom had not originated in the family.
“So now you’re blaming him, are you?” asked the social worker.
We had had a fire in the house about 16 months before Tom's regression and we were originally referred to the Lucena Clinic, Rathgar, with suspected post-traumatic stress disorder.
I got Tom’s diagnosis of autism spectrum disorder with the help of an art therapist and a private psychiatrist. This was confirmed by the Lucena Clinic which said he had “PDD-NOS”; “Pervasive developmental disorder, not otherwise specified” which translates roughly as “Something up with this child, your guess is as good as mine.”
We got a prescription for 0.25 Rispiridone daily which I finally administered to my son when I was persuaded that the trauma he was going through was real for him and this would help. He calmed down immediately and family life became possible for us again. Then I got him a place in a special school where he was in a class of six instead of sheltering from sensory over-load in the corner of a class of 30.
Our smiles returned and we got on with rearing four children, one with autism. I rarely mentioned to health professionals the fact that he had suddenly regressed at 4½ and when I did I was shot down.
Does it matter?
Yes. He matters. So do all the other people with CDD.
The experience of watching a child suddenly collapse and lose much of his or her ability between the ages of three years and even 10 years is beyond traumatic. Research suggests CDD affects 1:100,000 of the population, but as few, including many health professionals, have ever heard of CDD, I don’t believe the statistic.
Even if there really were only 70 families affected in Ireland, they need to be heard. Recognition of the disorder was worsened seven years ago when the American Psychiatric Association excluded subdivisions of autism such as Asperger's syndrome and CDD from its diagnostic criteria because it said there was not enough scientific evidence to clinically distinguish them from autism.
Kings College, London-based paediatrician Dr Michael Absoud, whose team identified 19 cases of CDD during a recent prevalence study for the British Paediatric Surveillance Unit, believes making the distinction from autism is vital because the late onset and the severity of the regression in CDD is "quite distinct and clear".
The health service needs to understand CDD, he says, because those affected can often have more mental health issues, more anxiety, more repetitive, self-soothing actions such as flapping and humming, more physical aggression and lower levels of attention than ASD-affected individuals.
How will we ever learn to distinguish CDD from autism, let alone treat or even prevent it, if we lump CDD-affected patients in with all other autism patients? Particularly if CDD isn't related to classic autism, but is a completely different syndrome originating in a different area of the brain? That's the thesis of Yale's School of Medicine professor of paediatrics Dr Abha Gupta, the world expert on CDD, whose preliminary study of 15 families suggests CDD is governed by completely different genes than those governing autism.
Most of the genes considered likely to contribute to autism are in the cortical, or “main” region of the brain which determines intelligence, personality, motor function, planning and organisation, touch, sensory processing and the processing of language. By contrast, the genes considered “candidates” for contributing to CDD were found by Gupta and her team to affect the “sub-cortical” brain regions: the amygdala, the hippocampus and the cerebellum.
Fourteen of the 15 CDD-affected subjects in Gupta’s preliminary study had rare gene mutations in one or more than 40 genes, 11 of which surge in activity between the ages of three and eight years, when CDD typically occurs.
While Gupta's team was analysing blood and saliva from affected individuals and the unaffected members of their families to find their genetic differences, the Yale Child Study Centre was doing "neuro-imaging" studies by conducting MRIs on non-sedated CDD-diagnosed kids (to contribute to Yale's study of CDD, contact yale.cdd@yale.edu). "They landed on the same areas of the brain in their MRI scans as we had in our study. There was a convergence of data between the two very different data sets, genetics and imaging."
To see the anxiety... the child staring in the mirror... hitting themselves, knowing something's wrong, something's happening... And to imagine the anguish of that family...
Gupta is recruiting a target of 50 further families to participate in a genetic analysis of CDD. This research could contribute to our understanding of what the “sub-cortical” regions of the brain do: there is emerging evidence, she says, that the cerebellum is related to “the social network of the brain” as it governs all the physical gestures which accompany language; the amygdala is “the emotional centre of the brain”; the hippocampus is thought to govern learning and memory but “CDD is showing us it’s not always doing that”.
But what was for Gupta the most exciting finding in the preliminary study was how the apparent genetic difference between CDD and classic autism spectrum disorders seemed to be supported by the different way in which affected children looked at others.
People with autism usually process faces atypically, giving no more attention to the eyes than to the rest of the face, leading to the difficulty they often have with eye contact. By contrast, the CDD-affected individuals in Gupta’s study focused on the eyes like babies do between the ages of four and 12 months suggesting a return to an earlier form of facial processing rather than a loss of social interest.
Gupta’s team was stunned. The CDD-affected subjects were overall much worse affected than the ASD-affected children and yet when it came to “eye-tracking” they looked more like typically developing subjects whose development had been arrested.
I felt a shock of recognition when I first read this research because Tom, too, has never failed to make eye contact like people with autism do. “I feel good that you’re telling me this,” says Gupta. “I feel like we’re on the right track. Perhaps.”
On the other coast of the US, at the Mind Institute of the University of California, psychiatrist Sally Ozonoff, who is contributing to Gupta's study by analysing video clips which parents send in, treats this finding with extreme caution. "It would have to be replicated. Why aren't there a whole bunch of other residual skills?"
She says the affected kids look the same as those with autism once the regression has happened. The regression itself, however, is quite different, happening between the ages of three and eight, and often presaged by a terrifying “prodrome” period during which the child is frightened and sometimes violent.
It is the job of Sally Ozonoff and her team to view “before”, “after” and “during” videos of these kids to attempt a CDD diagnosis for Gupta’s Yale-based study of CDD. Videos taken during the “prodrome” are the rarest and the most gut-wrenching, she says.
“To see the anxiety... the child staring in the mirror... hitting themselves, knowing something’s wrong, something’s happening... And to imagine the anguish of that family... ”
An “after” video might show that same child, his face blank, staring into space, “a seven year old who has lost everything”.
“We cry,” she adds simply.
He pissed in my shoes. He screamed, bit, fought as if possessed by demons
I can identify with this. Tom’s regression began with a period of withdrawal when he was about four and escalated into a full-scale “prodrome” in late July 2005, when my sunny boy suddenly exploded with anxiety and inexplicable violence.
He smashed all the vases in the sitting room and when I asked him why, he said: “I didn’t like them.” He pissed in my shoes. He screamed, bit, fought as if possessed by demons.
When the horror receded about a year later we were left with a visibly disabled child who did, I think, continue to regress slowly as he matured. While many of his IQ results in 2010 suggested borderline intellectual disability, in 2019 he came in as moderately intellectually disabled.
Often the regression is more sudden and more acute. I picked up a thriller called The Perfect Wife while on holidays and read JP Delaney’s description of a child being rushed to hospital with symptoms which seemed like seizures, but in fact signalled the devastating onset of CDD. The postscript makes clear that he was inspired by his son’s diagnosis.
What triggers this catastrophe?
That’s the rather more than $6 million question.
“Most people think it’s some sort of genetic anomaly which turns on after the age of three,” explains Ozonoff. “There are many conditions which switch on – dementia, MS... You may have those genes all your life. Who knows why they turn on. It’s fairly unlikely to be an environmental cause.”
The search for the cause is, of course, also a search for a cure.
The dream these professionals share is to find “targets for treatment” in the brains of children with CDD or, better still, before they get it.
Gupta wonders if there is a specific neuro-transmitter involved, is the serotonin (hormonal) system involved or the “mitachrondrial system” which governs genes from the nucleus of our cells? “Let’s say we found an enzyme which contributed to the development of CDD. If it’s an enzyme which we can target with a pharmaceutical treatment, that would be a best-case scenario.”
Some, such as psychiatrist Julie Wolf, Gupta's colleague at Yale, do not rule out that the development which seems to be lost may still remain in the child somewhere. CDD-affected people tend to have flashes of their former selves. And I can't help but feel the old Tom is in there behind the mist.
While preventing or reversing CDD remains a pie in the sky, it is, as Absoud says, “our duty as physicians to reach out to that”.
Gupta believes understanding the stark and severe regression involved in CDD will likely shed a lot of light on regression in general, which is a symptom of many disorders. But she is adamant, as are all the experts I have interviewed, the “devastating” condition of CDD deserves research funding for itself alone.
If nothing else, says Absoud, this “gives families a voice. Which is an important part of their journey.”