A recent case report published in the European Journal of Endocrinology highlights that repeated bone fractures can be a warning sign of systemic mastocytosis (SM).
The case report describes a 62-year-old man who experienced sudden, severe back pain after lifting a 15-kg (about 33-pound) weight. He was already living with several health problems, including high blood pressure, kidney stones, a past knee replacement and an unusual genetic makeup involving missing Y-chromosome material. Because of this genetic condition, he had low levels of the male hormone testosterone (a condition called hypogonadism) and had received hormone treatment as a teenager.
Imaging showed a broken bone in his spine, and doctors performed a procedure to repair it. But just nine days later, he had sudden back pain again. New scans revealed three more spine fractures and he needed a second repair procedure. Because he was breaking bones so easily, doctors looked for hidden causes beyond his low hormones.
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Blood tests showed that his level of a protein called tryptaseTryptase A protein enzyme that is primarily produced by mast cells and stored in small pockets within the cells, known as granules. High levels of tryptase are a key indicator of SM. (a marker of SM) was high at 34.9 µg/L, and his thyroid was underactive. Doctors then took a sample of his bone marrow and examined it under a microscope. Together with the high tryptase, this confirmed that he had SM on top of his existing hormone problem.
“This case highlights the importance of investigating secondary causes of osteoporosis in patients presenting with osteoporosis, as more than one contributing [factor] may coexist,” the case report’s authors said.
Doctors started him on thyroid medicine (levothyroxine) and midostaurin, a drug that helps stop abnormal mast cells from growing and dividing.
For his bones, the usual first-choice medicines are drugs called bisphosphonates, but the patient was worried about their side effects. So doctors chose a different bone medicine called denosumab, partly because there is evidence it may also lower tryptase levels.
Read more about mastocytosisMastocytosis Rare disease caused by the buildup of mast cells. Cutaneous mastocytosis primarily affects the skin and is more common in children, while systemic mastocytosis affects internal organs and is more common in adults. and bone disease: “Experts find several treatments effective in SM-related osteoporosis”
