Hi -- I apologize I have not read all of your posts or even all of this thread, but I have seen several of your posts about school refusal so thought I would chime in with some food for thought. Sorry if this duplicates info others have posted, I am just able to be on for a short stretches these days so hard to keep up with all the posts.
If you have not heard of PANDAS/PANS (p/p), you might want to do some research to see if it fits. Here are some disorganized thoughts to get you started:
1. "they" (some parts of the medical community) now think that p/p effects as many as 1 in 200 kids.
2. generally, p/p is an autoimmune response to infection (strep is well-studied and many believe other infections can also start the aberrant immune response but perhaps only after an initial strep started it - still being researched and studied) .... anyway, body gets infection, body fights infection by attacking the infection. In p/p victims, the body gets mixed up (several theories for why I won't go into in this post) and starts attacking the basal ganglia, a defined area of the brain. Brain inflammation (encephalitis) results, which can cause a wide variety of psychiatric and motor symptoms
3. There are two "major" symptoms, one of which is necessary for diagnosis, along with a multitude of potential "minor" symptoms, I think two of which are necessary for diagnosis. One of the major symptoms is eating restriction. School refusal is a minor symptom. Most kids who are diagnosed have at five or more of the minor symptoms.
4. One of the hallmarks of p/p is a sudden onset of the neuropsychiatric symptoms --- but there are times when they are more slowly realized
5. P/P is a diagnosis of exclusion ... there is no one test that will say "this is p/p" ... but there are things that can be done to rule it in or out. And they are quick and for the most part cheap.
6. If you see THESE things in your kid, especially if they have abruptly appeared or become greatly exaggerated over a short time, you might want to read more about p/o:
a. OCD (can be stuff like washing hands too much; can be intrusive thoughts you don't see)
b. Eating restriction (actually binging can also, but more rarely, be the presentation) -- harder to distinguish from ED in older kids, but when a three year old suddenly restricts, p/p should be thought of (20% of p/p cases involve eating issues)
c. Urinary frequency or accidents in a person who otherwise had no such issues. (90% have it ... but my kid did not) -- if your kid has this, they say p/p must be further investigated
d. sleep problems
e. handwriting deterioration -- google this. the differences in kids pre-p/p flare and in flare are astounding - an 11 year old will draw a picture of a castle and it is great ... two weeks later they start a flare (brain inflammation) and it looks like a two year old is drawing ... six weeks later after antibiotics or other treatments and it goes back to a great drawing. Again, if your kid had good penmanship and suddenly it is very different, p/p must be further investigated
f. behavioral regression (baby talk; separation anxiety like a toddler.. which can be a "reason" for school refusal; tantrums that had been outgrown return). the separation anxiety can be from a parent but also from the house and actually even from one area of the house (sometimes their own room)
g. panic .. actually can see it in their eyes ... often with huge pupils and in looking scared and not in control of the panic
Generally, if you think p/p fits your kid, you want to see if there is an active infection and if so, treat with antibiotics (often an extended course). Many doctors who look at a chronology and rule p/p in will give antibiotics diagnostically ... like 14-30 days of amoxicillin to see if the symptoms lessen. Often they all but disappear just with the antibiotic. It is truly remarkable. Other doctors suggest a diagnostic course of 24/7 ibuprofen (they had my kid on 200 mg three times per day ... but that was not at a time of flare so I don't know if that would have been initial dosing). The idea being the ibuprofen reduces the swelling in the basal ganglia... again, for some people it helps enough to suggest the symptoms are in fact from encephalitis. Steroids can also be used diagnostically. THEN if p/p still seems to be in the differential, you keep going from there. EDITING TO ADD: I am absolutely not suggesting you try dosing with antibiotic you might have at home, or ibuprofen, on your own .... please only do so with a doctor's guidance.
I found that the best way to get introduced to p/p was to watch youtube presentations ... doctors at conferences presenting to other doctors and/or parents. If you just want a taste to see if you think this could apply (and I by far did not set out all the situations where a parent should look into p/p), I would go to youtube and put in Swedo 2019 Saskatoon -- Susan Swedo is the pioneering physician who first identified that strep is resulting in the brain changes presenting in these ways (you can sort of think of it as rheumatic fever of the brain, rather than the heart).... she has tons of video but that one is pretty recent and I would not bother with anything before 2019 since there are so many to choose from .. this Saskatoon one is about 50 minutes and gives an overview. The other presenter I like a lot is Miroslav Kovacevic -- youtube his name and find a 2019 video .. again usually about 50 minutes. He has one from about 5 months ago where he presented to an autism group.
You will find a lot of controversy about p/p and if it really exists. But I think the controversy is what should it be called and is it on a spectrum with something else or is it a separate thing. There is really no denying that something is happening with these kids, and there is absolutely no denying that treating them for p/p has dramatic results that are not seen with similar treatment in kids with similar symptoms when encephalitis is not at play. So I would encourage you to not get bogged down in the controversy ... take a look and see if your kid fits and if so, post back and we can help you get to the right medical person to pursue it with. Some of these kids (mine included) live in a chronic smoldering flare for years bc doctors don't yet connect the dots very quickly ... but like I said, with eating restriction and school refusal/panic the way you have described, it seems like maybe watching two hours of video if you can fit it in will be useful to help you decide if you should look at p/p further or not.
Wishing you well!! Also, I have to run so not going to proof this very well. ... sorry.
editing to add: just realized you are UK -- there will be 2019 UK talks by Swede on youtube and you guys have a big push right now to educate doctors on p/p ... but to be honest I'd still look at the videos I put up top .. but if you think p/p a maybe for you, you have at least a couple of doctors who are really keen to pick up the p/p ball and start treating it in the UK.