Biopsy Results Negative Rheumy and GP still Calling it GCA & PMR

The biopsy result being negative is fairly meaningless - it only means they didn't find what they were looking for but there are many reasons for that, not least that GCA isn't affecting the temporal artery or that the fact it occurs irregularly means there are areas of tissue that are perfectly normal between the bad bits. Like there being good road surfaces between patches of potholes! The only reason the temporal artery is used is that it is easily accessible and you can manage without it. GCA affecting the occipital area is a far greater risk but there is no way to image or biopsy that, and the ways of imaging GCA affecting arteries in the chest area can't show what sort of inflammation it is - whether there are giant cells or not. Other drugs are used in other forms of vasculitis but they aren't as effective in GCA.

So GCA (and PMR) remain a clinical diagnosis: based on the signs and symptoms, clinical history and response to pred. What you describe is typical - if there is such a thing - but your symptoms coincide with what loads of people experience in GCA.

My own suspicion is that you need more - if it isn't enough to thoroughly clear out the existing inflammation then even a small amount being created each day takes you into the symptomatic level. Many rheumies support the idea of starting with a pulse therapy - 3 days of very high dose infusions of methyl pred, sometimes 100mg/day or more, and then switching to high dose oral pred, sometimes starting with a few days of 80mg. If you haven't used enough pred the symptoms will persist longer, even if they are reduced. In PMR it doesn't matter as much that it takes a month to get the inflammation under control - but GCA is something else.

Perhaps the bad news is that if the tinnitus is due to the GCA (and it often can be) it may take a long time to improve. I had relatively mild tinnitus with what has always been said to be "just" PMR suggesting the blood flow to the nerves in the ear was compromised (I had jaw claudication) and it took months to disappear. Nerves are notoriously bad at regenerating.

I suspect there is a narrow line between being paranoid and merely being worried - and after just 3 weeks or so you have a long way to go to learn about YOUR personal version of GCA. In the absence of a 100% definitive test for either PMR or GCA you have to accept this is the most likely diagnosis and probably the most urgent to rule out by your response to the right dose of pred.

I would just add that I think you are very lucky your medical people are basing your treatment on your symptoms.  This is the way it has to be with PMR/GCA.  There are people on this forum who have had to reduce their pred drastically based on test results, in the face of increasing symptoms, and suffer greatly, so it seems you are being treated based on best practice.  You will always find support here.  The early days and weeks are the hardest, but as Eileen says as time goes by you will find the best way to manage your particular version of this incredibly frustrating ailment, and it seems you have the support of knowledgeable doctors.