Thank you very much for the useful information Karyn.
The first and most important step is to rule out the possibility of an ongoing infection since you have low white cell count (which predisposes to infections); fever (a sign of infection); abdominal pain (which can be due to intra abdominal infections such as infective colitis, parasitic infestation, gall bladder infection, pancreatic inflammation, or infection involving the urinary tract).
I say this because patients with adrenal insufficiency are prone to have infections, and when this happens, they tolerate the infection badly and require not only a prompt infection treatment (in the form of antibiotics); but also the dose of their steroid hormones need to be escalated to bear the period of physical stress (due to infection). If these measures are not taken in time, one can go in to adisson's crisis which is a life threatening and serious situation.
So you have already doubled the dose of steroids, but persistant vomiting and abdominal pain need to be investigated further.
Inflammatory markers (like crp/esr) along with fresh cbc will be helpful along with an abdominal scan to look for any possible pathologies in the abdomen (such as gall stones giving infection, renal stones giving infection, or pancreatic inflammation).
And since you have ongoing fever, you need a course of broad spectrum antibiotics (which we can hold in an otherwise healthy patient but not in a person with pre-existent adisson's disease).
Any physical stress/infection can also trigger fibromyalgia as well which might be contributing to your pain.
And finally, yes, your spine need to be investigated as well by means of an MRI (to look for a possible disc prolapse, vertebral degeneration or collapse).
So the stepwise approach here is;
Look for and treat the infection (tests and treatment).
Enhance/start fibromyalgia medications like pregabalin if there is no abnormality (like an infection) found out.
Also, there is no harm to get tested for H.Pylori, a bacterial infection of stomach that can give your persistant stomach symptoms.
You should get back to your doctor, discuss all the details i have mentioned to get a management plan chalked out that suits best to your needs.
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