Hereditary alpha tryptasemia

This code represents hereditary alpha tryptasemia, a genetic condition characterized by an increased copy number of the alpha-tryptase gene (TPSAB1). This leads to persistently elevated baseline serum tryptase levels, often without clear evidence of mast cell activation disorders. Patients may experience a range of symptoms including flushing, itching, gastrointestinal issues, and connective tissue abnormalities.

Assign this code when documentation confirms a diagnosis of hereditary alpha tryptasemia, typically identified through genetic testing for increased TPSAB1 copy number. It is appropriate for patients presenting with chronic, unexplained symptoms consistent with elevated tryptase, where other causes of mast cell activation have been ruled out. Documentation should clearly state the diagnosis of hereditary alpha tryptasemia.

• Do not confuse with acquired mast cell activation syndromes or other mastocytosis codes, which have distinct diagnostic criteria.
• Ensure genetic testing results or a definitive clinical diagnosis of hereditary alpha tryptasemia are present in the medical record.
• Code any associated symptoms or manifestations of the condition separately, if applicable and documented.