Regression and early development unusual, is this usually due to autism?

[used2bthin]

DD who I have posted lots about recently, has no diagnosis of autism jus various reports explaining her issues such as SLI, learning difficulties, developmental delay, sensory processing difficulty and more.

She now has challenging behaviour but her behaviour was almost unusually relaxed unti the last couple of years and I think is more frustration than anything, her speech problems are so severe that poeple can't understand her and she gets very confused by language too.

Anyway at ten months- a year she had a few words and was developing normally but somewhere between a year and 17months when I took her to the doctor and the process all started, she lost all language other than one "word" which was used for everything.

We've had loads of tests now and other than developing seizures now too and finding some minor genetic fault we have no explanation but am I right in thinking that thsi usually happens with autism rather than SLI? Also she never sat up, just rolled then crawled and her development has always been a bit all over the place-she used to draw well a year ago but now has fine motor problems and doesn't just as one example and she quickly forgets things if they aren't done everyday.

The initial regression fits asd but I am not sure much else does. DS had a big regression but been on an upward curve since then.

While asd children might have little regressions when they are ill / during changes etc losing skills on and off over a longer time is not the typical pattern if its just asd and nothing else.

The seizures might explain the repeated regressions / memory issues better. She could have been having mini seizures before they became physically apparent. Have the seizures been properly investigated and any neurological conditions been ruled out? Has a neurologist been involved?

We looked at something called Landau-Kleffner when DS first regressed and there are other epilepsy based conditions which can co-exist with autism or on their own.

Thanks yes the neurologist said its not llandau kleffner can't remember why though. It was thought to be epilepsy, we even had a prescription for meds then she had some fits while in hospital for her genetic condition and the diagnosis was changed to reflex anoxic seizures which was a good thing really.

So would the language regression sound typical with autism? The other stuff is less marked in that it seems to come and go and also I wonder if I just didnt notice the fine motor probs because compared to her speech those skills seemed advanced iyswim?