Many of the behaviors that you described for this boy are common among people with a diagnosis of ASD. They include impaired communication, mood disturbances, poor motor skills, problems with writing, and wetting himself when playing. The latter behavior may signify an intense interest in the game being played. I've had teen-aged clients with ASD who have done the same thing repeatedly. For such individuals, playing the game seems more important to them than using the toilet. Furthermore,, wetting oneself despite having been toilet-trained shows a lack of social embarrassment, and a failure to recognize and/or be concerned about disapproval of others who probably would view his refusal to use the toilet as socially inappropriate. Of course I can't be sure that your client doesn't have some other comorbid conditions, but the behaviors that you listed are consistent with a diagnosis of ASD.

I think the symptoms you describe are consistent with the ASD diagnosis. However, a regression around 2-3 years old could be a neurological indicator of some severe forms of epilepsy. Did he have an EEG?

Thank you all for your answer - I am also concerned over the possibility of him having seizures. The thing is he actually has no visible signs of epilepsy, and no EEG. Because of his family complication I have not yet brought up the possibility to his parents, I just want to confirm on my part first. May I please have some more information site/scholar articles on ASD vs. epilepsy, and some of the signs and symptoms so that I can refer him to a neurological examination?

Page 59 of DSM-5 indicates that medical conditions commonly associated with ASD include epilepsy.

The following publication also may be of interest to you.

El Achkar, C. M., & Spence, S. (2015). Clinical characteristics of children and young adults with co-occurring autism spectrum disorder and epilepsy. Epilepsy & Behavior, 47, 183-190.

I was able to find this reference using Google Scholar. If you access it that way, you'll be able to read the article's abstract.

Concerning those symptoms, I agree about the epilepsy hypothesis. Actually I would suggest considering the possibility of a Landau-Kleffner syndrome.

There is some research regarding this topic. You can find it easily at Google Scholar. You can even have access to many of these publications:

Deonna, T. & Roulet-Perez, E. (2010). Early-onset acquired epileptic aphasia (Landau–Kleffner syndrome, LKS) and regressive autistic disorders with epileptic EEG abnormalities: The continuing debate. Brain and Development, 32(9), 746–752.

The behaviors you describe are certainly consistent with a categorical diagnosis of ASD.  Having said that I would recommend evaluation by a pediatric neurologist to rule out seizures and to evaluate for co-occurring medical conditions such as FXS or other conditions - does he have unusual physical characteristics such as cafe au lait spots, large ears, hyperflexible joints, pectus excavatum. Does he have blue eyes? The intense interest in toys certainly does fit the restricted interests definition.  Another thing to consider is that ASD is also co-morbid with mood disorders in families so is there a family history of same?  Is there any seasonal or other pattern to his mood swings?  How are his sleeping and eating habits?  Finally, what is the quality of the ABA intervention?  Are the teachers or supervisors board certified or similarly qualified?  Do parents follow through?

I agree with previous answers that you describe the presence of typical ASD symptoms and that the boy may very well have a comorbid neurological condition. So, after having discussed this with the parents (and have consent) you could have a consult with a local pediatric neurologist. In addition to an EEG perhaps also a head CT could be be relevant.

I agree with Luz Uribe...LKS sounds entirely feasible. Definitely more than autism going on, even in combination with epilepsy the degree of aphasia and lack of progress despite intensive therapy points to a comorbid neurological condition. Here's another article which may be useful:  Acquired Epileptiform Aphasia: A DimensionalView of Landau–Kleffner Syndrome and the Relationto Regressive Autistic Spectrum DisordersGerry A. Stefanatos, Marcel Kinsbourne and Jeanette Wasserstein  full article available on academia.edu, sorry the direct link didn't work. Good luck!

contact dr Linda Lawrence opthomologist and behaviorist

Dr. Linda Lawrence

Tell her that I recommended she do so because she has worked with many similar similar cases and found that often vision is causing many of the problems and can recommend what you might do

Behavioural intervention doesn't work for many children with ASD, and there are a wide variety of other interventions available. Looking at the child's sensory-perceptual profile would be helpful in terms of adapting the home and school environment to meet his needs--and may also help to reduce seizures or seizure-like episodes if these are occuring. A full neurological workup---not just an EEG--is a good idea. Do you have a developmental clinic available? I would think that a good research hospital in the Sydney area would have access to one or more neurologists with expertise in this area.

I certainly agree that this child needs a complete neurological work up and that ruling out epilepsy is a key target. The LKS story is quite likely applicable. I appreciate your vantage view of the family, yet the potentially significant changes from prompt treatment may be a strong enough motivation to hasten the needed assessments. 

This child sounds like he has ASD and intellectual disability. Has he had a cognitive / developmental assessment to look at intellectual functioning? He also sounds like he has sensory issues and would benefit from being seen by an occupational therapist. Visual supports and strategies would support development of communication skills under supervision by speech and language therapist. I agree that he should be seen by paediatric neurologist to look at other possible issues.

I have just reread your synopsis Ruochong. I am wondering about his prolonged sitting tolerance over the past year being one of his strengths...to me it could indicate his functioning has declined even further, particularly when you consider he is now wetting his pants rather than going to the toilet. I also wonder whether he is  "engrossed in play" at these times, or if he is actually having absence seizures, or just totally regressed into his own world? Have any professionals observed him at these times, when he wets himself? What is his behaviour like following these times, i.e. does the mood turbulence, shouting, jumping crying, etc happen after these episodes? Could this indicate a post-ictal state?

As a parent who has raised a child with autism.. It sounds to me like they are not intensifying the speech therapy enough. He should be getting at least 5 sessions a week of individual therapy lasting at least 45 mins long. It should not be group therapy but individual either in or out of the classroom. It made the world of difference for my son. My son was not toilet trained until third grade and had cognitive ability of less than  a year old at 4. Intense behavioral interventions can only be successful if the speech is intense as well.

In 2011 He graduated high school fully verbal with his peers. :)

Maybe he has a sensory based dyspraxia or apraxia of speech. If he mainly shows speech and language problems, but not the typical autistic differences, he probably was misdiagnosed with autism. Some behaviors sound like he is seeking intense sensory stimuli, maybe because he is hyposensitive. Maybe you want to suggest a comprehensive assessment of sensory functions and praxis and start a more clinet-centered developmental approach (such as OT using an ASI approach).

OT= occupational therapy

ASI = Ayres Sensory  Integration

I guess you should get the pediatric neurological and child psychiatric consultation. As the child is showing regression even in the motor skills , he needs to be evaluated for childhood dis integrative disorder or any other variant.