[Idiopathic mast cell activation syndrome].

Area of Science:

• Immunology
• Gastroenterology

Background:

• Idiopathic mast cell activation syndrome (MCAS) is a cause of recurrent, unexplained symptoms.
• Diagnosis of MCAS can be delayed or incorrect due to symptom diversity.

Purpose of the Study:

• To present a case of idiopathic mast cell activation syndrome (MCAS).
• To highlight the diagnostic criteria and successful treatment of MCAS.

Main Methods:

• Case report of a patient with recurrent attacks of itching, skin redness, diarrhea, and near collapse.
• Monitoring of serum tryptase levels during symptomatic episodes.
• Treatment with a combination of H1 and H2 blockade.

Main Results:

• The patient experienced recurrent episodes consistent with MCAS.
• A significant rise in serum tryptase was observed during an attack.
• The patient showed successful response to H1 and H2 blockade therapy.

Conclusions:

• MCAS is characterized by recurrent symptoms and requires a significant rise in mast cell mediators for diagnosis.
• Many patients with unexplained symptoms are misdiagnosed with MCAS.
• Combination H1 and H2 blockade can be an effective treatment for idiopathic MCAS.