Potential etiologies of flushing include rosacea, carcinoid, pheochromocytoma, pancreatic VIPoma, medullary thyroid carcinoma, renal cell carcinoma, mastocytosis, alcohol, medications, psychiatric or anxiety disorders, and idiopathic. High on the differential for facial flushing and diarrhea is carcinoid. In terms of laboratory testing, this can be diagnosed with 24-hour urine for 5-HIAA and serum serotonin. In terms of imaging testing, this can be diagnosed with CT (or MRI) with contrast; alternatively, consider nuclear medicine octreotide scan (somatostatin receptor scintigraphy). Some of the etiologies listed above, especially neuroendocrine tumors, are more conspicuous and sometimes only visible on arterial phase of CT. I just wanted to point that out since a routine contrast-enhanced CT typically only includes venous phase. However, given your clinical presentation, you should consider multiphasic CT which includes both arterial and phases.
Sample algorithm for evaluation of patients who present with flushing:
https://www.semanticscholar.org/paper/The-flushing-patient%3A-differential-diagnosis%2C-and-Izikson-English/8c97af66e6b09e4c38890f8dffd78286539fbd73/figure/0
Source: Izikson L, English JC, Zirwas MJ. The flushing patient: differential diagnosis, workup, and treatment. J Am Acad Dermatol. 2006 Aug;55(2):193-208.
I am not sure why you are concerned about brain cancer. Your clinical presentation does not support that at all. Here are some zebra diagnoses more likely than brain cancer, although still unlikely overall: For a 30 year old female with arm/leg pain/tingling, headache, bowel/bladder issues, and other random symptoms, you may want to rule out multiple sclerosis. For someone with skin rash, weight loss, and other random symptoms, you may want to rule out systemic lupus erythematosus.
When you have chronic diarrhea, you're not holding onto your food long enough to absorb the nutrients you need. So while all of the above can be looked at, having the diarrhea you're having and the color it is indicates something is wrong with your digestive system. So many things can affect this so have no idea why it's happening, just suggesting that when you don't absorb food you are in essence partially starving. Might explain the other symptoms. Know that IBS isn't a diagnosis, it's a description, in that it doesn't tell you why you have it.
Hi, Karma, have you thought about this: two people in the same house, not DNA related, and both have mystery inflammatory conditions. Even SpA is a mystery in that it's not thoroughly understood regarding what it is and what causes it.
Therefore, it's possible there is some trigger involved - food, mold, pollen or whatever. A rising level of general baseline inflammation can make the immune system more likely to over react in specific ways, ways that can vary depending on the individual.
"A month ago I started having daily facial flushing every evening."
That also looks like a trigger at work. Wine with dinner? Asians are most likely to have the Asian Flush, but anyone lacking the Aldehyde Dehydrogenase enzymes can experience the same thing plus, other effects.
With your 5-HIAA test ruling out serotonin flushing, you can look at histamine from mast cells as the cause. That can result from a huge variety of triggers. Even the journal AAAI is catching up:
Mast Cell Disorders: Protean Manifestations and Treatment Responses 2017
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6026564/#
"Protean Manifestations" describes your history, of course.
I'd be wary of any doc who thinks that a normal tryptase test is reason to rule out MCAS - though it might tend against mastocytosis. Both Theoharides and Afrin say so, being the 2 top MC docs. Besides, you should obviously be tested right after a flushing episode, right? Esp for the histamine metabolite n-methylhistamine in urine.
Btw, I'd also be wary of any allergist *if* they believe that skin prick testing can tell about what happens with the MCs in the GI.
Karma, what you want to know is the Negative Predictive Value of the two blood tests, such as here: https://www.ajronline.org/doi/10.2214/AJR.12.9758# The chromogranin-A test apparently does much better than the serotonin metabolite test. But other papers show different NPV % numbers.
NPV means the chance that you truly don't have the condition if the test says you don't have it. (So 100% NPV means you surely don't have it.)
I'd guess that the CT scan might not have looked in the offbeat places where a carcinoid tumor might be. (Btw, I would also have guessed that they would have done the CT to locate a tumor only if the Ch-A had said there was indeed a tumor somewhere.)
I bet you have an allergy. I have a severe soy and milk allergy that affects my brain (dizziness, panic attacks, cloudy thinking), causes muscular pain and IBS. Found out after being hospitalized last year. Before any tests my gastro doc said stop eating dairy immediately, get skin prick allergy testing and look into an elimination diet challenge of the top 6 food allergens. Of course all of my many many blood tests, MRIs, esophagram and endoscopy came back 100% normal. However there is a “non-ige” type of allergy that there is NO test for. The only way you find out is elimination diet for 3 weeks, then slowly add back in each of the 6 until you find what affects you.
After 3 weeks I felt better than I have in 10 years. My anxiety vanished along with my other symptoms. As I added back each milk and soy and all of the symptoms returned.
Here is how it works for me. If I accidentally have a trace amount of soy for example, I will get immediate stomach discomfort, but then 2 DAYS later I get all of the mental disorder symptoms back and it lasts for 2 WEEKS. This is why it is so hard to nail down what food you are allergic to.
Make a food log and if you feel worsening symptoms, consider what you ate up to 2 days ago. There is no cheating on this kind of diet. Trace amounts make me feel like I’m dying for 2 weeks. No ice cream is worth that hell. Make a commitment and eliminate dairy, soy, eggs, wheat, nuts, seafood for 3 weeks and see how you feel. If your symptoms are better, add one food type back in one week at a time. 80% of people with a food allergy are affected by more than one allergen so don’t stop when you find one culprit.
Hope this helps, good luck!