Chasing Zebras: An NP Perspective on Being a Patient with an Undiagnosed Illness

When making a medical diagnosis, providers are told to rule out the "horses" before looking for the "Zebras". A zebra is defined as a very unlikely medical diagnosis. A good example is jumping to the conclusion that a mild headache is a brain tumor before ruling out other causes. The health care team should always rule out the life-threatening potential diagnoses associated with a set of symptoms, but also be looking for the most obvious and common causes of those symptoms. When none of the standard explanations fit, then we begin looking for Zebras.

Many of my family and friends know my saga... Numbness and hyperalgesia (increased sensitivity to pain) that began in early July. It started on my right side (first my face- leading to a diagnosis of Bell's palsy, but quickly down my arm and leg). Tests were done to rule out all of the scary or life-threatening things (Lyme, MS, Guillain Barre, Myasthenia Gravis, Meningitis, Neurosyphilis , HIV, etc). My neuro exams were always normal. The only thing abnormal was sensation. The symptoms spread to my left side and everything felt incredibly heavy. My legs and cheeks have been the worse. It isn't noticeable to others but for weeks it felt like it took immense effort to smile. My tongue was numb first on the right and then bilaterally, and any worsening of symptoms led me to feel like someone under the influence of alcohol who was trying to pretend I was sober. It took great effort to feel like I was speaking normally. After a while, these symptoms make you start to question your own sanity. None of them are testable or visible to others. I asked my doctors repeatedly if they could be psychosomatic but the feeling was that they were related to a physiologic insult. My EMG (Electromyelogram- fairly painful test of the electrical activity of muscle fibers) was normal. My MRIs and CT scans were normal. The only working theory was that I had developed a post-viral neuropathy which meant a cold virus I had before these symptoms started somehow affected my nervous system. The fact that it was on both sides and over the entire body was unusual. The neurologist told me that we likely wouldn't find the cause, but that it should get better over a period of months (from my reading I knew it could be up to one year or more).  

By August we were looking for Zebra diagnoses that explained my strange constellation of symptoms. At this point I was crowdsourcing my diagnosis (to colleagues, laypeople, everyone)... I was willing to consider any and all potentials and kept a running list of the things we hadn't yet tested for that we should consider. I was also working on accepting that likely we might never know the cause or how to make it better aside from sitting and waiting.

It was also in August, the really bothersome symptoms started- I had episodes randomly in different places all over my body of feeling like there were fire ants crawling on my skin, or of a burning/itching sensation. It wasn't traveling along a specific dermatome or nerve path. It was completely random and uncomfortable. I tried Gabapentin which I eventually stopped because I felt foggy all the time. I told my colleagues I felt like I had "gone from an A student to a B student". In addition to the fogginess I had a rising anxiety. I often felt like I was crawling out of my skin. It reached a fever pitch in September. I was able to exercise and physically could do everything I did before July, but the symptoms were getting the better of me mentally. My primary care physician was amazing and helped me navigate all of this. In mid-September, after many conversations, I mentioned to her something I hadn't thought of before: ever since last October, when I exercise and then go out into cool air, I break out in hives. The first time it happened it was disconcerting, but it happened a few times over a several month period so I didn't think anything of it. My PCP immediately suggested I see an Immunologist/Allergist who works in the local area and likes "zebra" cases.

At the same time, I took more control of the things I could control. I was back to baseline in my workouts. I started eating an autoimmune diet (thanks to the suggestion of a dear friend), and began acupuncture treatments. Two weeks ago, I saw the immunologist/allergist, who told me that my case was definitely "weird" (in a nice, "You are an NP so I can tell you that you are a zebra" way).  I told him about the numbness and the painful symptoms. Then I added in the hive piece. He immediately said "You have cholinergic urticaria". What the heck is that, you ask? It is an inducible hive disorder in which hives are causes by environmental stimuli (heat, cold, exercise, etc). The Mast Cells in the body (which are important in immune response and allergic response) are involved in the reaction, releasing histamine in the skin. (Too much of a good thing with those Mast Cells in this case).

What he said next really had me intrigued: people with chronic hive disorders often have a prodrome (an early symptom that indicates the onset of a disease or illness). This is often described as transient and patchy, either itching, burning, or painful sensations. The fix? An antihistamine like Loratidine (Claritin) every day to prevent the histamine release. He told me to try that for two weeks and if the painful symptoms improved, we know they were caused by the chronic urticaria. He said he couldn't fix or explain the numbness, but again reiterated there was nothing to suggest it was life-threatening. That said, there was hope that perhaps we had an answer to the painful symptoms. Two weeks later and the claritin is working. Today I had an episode of post-workout hives but I think that was in part due to eating some new foods I hadn't been eating on the autoimmune protocol diet. 

So apparently I have two unrelated issues, and the numbness and hyperalgesia have been making the hive disorder feel a lot worse than it had previously. Even on a day like today when the symptoms flare up a little, at least I know we have a path and a plan. I wouldn't have chosen to be a Zebra, but I'm thankful for persistent healthcare providers who helped me get to the bottom of things. (At least some of the things, since the numbness and hyperalgesia are still an issue, but I am hopefull they will improve).