Twenty years ago, on the first day of my final year studying biology at university in Missouri, I collapsed. My heart was racing, I was dizzy, disoriented and weak. I was 21 and had been feeling unwell over the summer;doctors thought it might be glandular fever, but this was much worse. When I didn’t improve, I was sure I had succumbed to the same mysterious, chronic illness that had crippled my mother since I was a child.

We were both in tears when I rang to say I was dropping out and coming home to St Louis. Bed-bound 22 hours a day, we supported each other, while friends helped with shopping. I had spent my life watching specialists fail to diagnose my mother, and now the same was happening to me: no condition they could think of explained our symptoms. Months, then years, slipped away as friends moved on with their lives, leaving me isolated and heartbroken. I realised that if I wanted a diagnosis, I’d have to find it myself.

After much reading, I theorised I must have a form of dysautonomia: a disorder of the autonomic nervous system, which controls essential bodily functions like blood pressure, heartbeat and metabolism. There were only a few specialists in the US, so I scoured medical resources. I remembered one doctor saying my symptoms changed too rapidly for it to be a thyroid disorder; but when I read that adrenaline disorders could mirror thyroid disorders, I thought my adrenal glands, located above the kidneys, might be malfunctioning.

I knew I needed to meet autonomic specialists, so in 2002 I submitted a paper to the American Autonomic Society’s annual conference in South Carolina and was invited to present it. In a wheelchair, I gave my talk about my condition and proposed a treatment.

Afterwards I was approached by a grey-haired man called Dr Coghlan, who said he thought I was on to something. We kept in touch, in time becoming a team, honing my diagnosis by phone and email. We framed my condition as “primary hyperepinephrinemia” – too much adrenaline from the adrenal glands.

First, we tried a risky treatment via a drip 24 hours a day, repurposing an existing drug. That lowered my heart rate. I could function for short periods, but would always be an invalid chained to an IV unless we found a permanent solution.

For two years we searched for a tumour on my adrenal glands. When scans came back negative it was a big blow, and I cried and cried. But in 2006 I had a fourth, highly specialised nuclear medicine scan, and, finally, we had our answer: it revealed my glands were glowing brightly, producing way too much adrenaline. If we could stop that, we could halt the condition.

I decided to create my own surgery. I found decades-old studies showing that an operation to remove the glands’ inner medullae, the source of adrenaline, had been performed on rats and dogs – but not humans. I reasoned it could be scaled up.

As much as my life had been derailed, I loved knowing I was breaking barriers. It took 18 months to find a surgeon to agree, but in September 2010 I had my first medullectomy. Within a few weeks I could sit upright for three hours without the drip. On Christmas Eve I walked the mile to church. I was amazed by the little things I could do. My mother was too ill to have the surgery; but with my drug treatment she lived her last eight years with less pain and in better health.

I later had the right medulla removed too, and although there were complications and it took 18 months to get the medication right to balance my hormones, by autumn 2013 we had cracked it. The fatigue had lifted, and I took my first holiday in 14 years. I flew with friends to the Bahamas and saw the ocean for the first time. I let sand run through my fingers, and caught lizards as I had done as a boy.

My health is fragile but stable, and I’ll be taking a cocktail of drugs for the rest of my life. I work as a speaker and personal medical consultant, sharing my knowledge of rare disease diagnosis. The same surgery has since been performed on other patients.

Throughout, my Christian faith was a great support, but I am a scientist, too. Science is the history of people solving mysteries: that sustained me when I was told I was attempting the impossible.

• As told to Mike Pattenden.

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