A staged examination involving a blood sample taken via a catheter inserted into the groin directly at the parathyroid gland yielded an unexpected result: the level there was perfectly normal! However, a parathyroid hormone test carried out via a standard blood sample taken from a vein in the arm showed that the level was far too high! This meant that the parathyroid glands in the neck were apparently fine and that there must be tissue elsewhere producing parathyroid hormone uncontrollably.

After countless X-rays and MRI scans, the breakthrough came: in August 2025, a fifth piece of tissue, approximately 3 millimetres in size, was discovered behind the breastbone in the area of the thymus; this was also secreting parathyroid hormone and could explain the discrepancy between the blood values from the neck and the arm vein. A subsequent operation in December 2025 at the University Hospital in Cologne removed the retrosternal thymus and surrounding tissue using a Da Vinci surgical system. A subsequent pathological examination confirmed that a parathyroid adenoma there had been secreting parathyroid hormone uncontrollably.

Just four weeks later, most of my blood test results were back on track to return to normal. In particular, my parathyroid hormone levels – and consequently my calcium and phosphate levels – were back within the normal range after just a few days. This was followed by a change in diet (cutting out sugar and alcohol), weight loss (with the help of a weight-loss injection), and increased physical activity and exercise. Whereas previously I couldn’t walk 200 metres at a stretch without having to sit down, I was soon back to walking 2, 3, 4, 5 kilometres at a go. By July 2025, I had already completed the 25-kilometre Siebengebirge hike. It wasn’t without its problems, and it wasn’t without pain. But I gritted my teeth and managed it in just over 8 hours!