Table I.

Clinical Summary of Patients with Mast Cell Activation Syndrome and Systemic Mastocytosis

Patient	Sex	Age at Diagnosis (Years)	Symptoms	Tryptase (ref ≤ 10.9 ug/L)	24 Hour Urine Studies*				BM Biopsy	Treatment
					NMH (30–200 mcg/g Cr)	LTE4 <104 pg/mg Cr)	PGF2 (<5205 pg/mg Cr)	PGD 2 (100–280n g)
1	M	48	Intermittent spontaneous urticaria, periorbital edema, and flushing. Anaphylaxis (abdominal pain, generalized pruritus, shortness of breath) triggered by fruit (mango, apple, cherry, nectarine). One episode required epinephrine.	Baseline: 17 ug/L 17.8 ug/L	Nl	Nl	Nl	Nl	Nl	Antihistamines PRN
2	F	54	Intermittent episodes of angioedema (tongue), shortness of breath, rash. Hypotension with opioid.	Baseline 6.3 ug/L unknown if baseline or with symptoms 15.4 ug/L	Nl	Not obtai ned	↑	Nl	Declined	Fexofenadine 180mg qAM, loratidine 10mg qPM, montelukast 10mg daily
3	M	47	Intermittent urticaria and angioedema (lips). Intermittent episodes of abdominal pain and shortness of breath	Baseline: 7.1 ug/L 12.5 ug/L	Nl x 2	Nl x 2	Nl x 2	↑ x 2	Nl x 2	Fexofenadine 180mg qAM, ceitirizine 10mg qPM, ketotifen 0.5mg daily
4	M	47	Intermittent urticaria. One episode of severe anaphylaxis with ST elevated myocardial infarction, consistent with Kounis syndrome. Occurred after consumption of pork loin.	5.1 ug/L 24 hours after symptom onset. Baseline unknown	↑	Nl	Nl	Nl	Not performed given need for aspirin	Cetirizine 10mg daily, famotidine 20mg daily, montelukast, ASA 325mg
5	F	28	Monthly episodes of idiopathic anaphylaxis (nausea, abdominal cramping, generalized pruritus, urticaria, hypotension/orthosta sis; 2 episodes with respiratory distress). One episode required epinephrine.	Baseline: <2.0 ug/L During episodes: 4.4, 3.2 ug/L	Nl	↑	↑	Nl	Nl	Failed combination high dose H1 antagonists, H2 antagonists, and montelukast. Did not tolerate cromolyn Controlled with omalizumab
Patient	Sex	Age at Diagnosis (Years)	Symptoms	Tryptase (ref 10.9 ug/L)	Bone Marrow					Treatment
6	F	27	Childhood diagnosis of urticaria pigmentosa by skin biopsy. Anaphylaxis (urticaria, abdominal pain, diarrhea)	Baseline: 15.8 ug/L 11.7 ug/L	First bone marrow (2005): +CD2/CD25 and +D816V Second bone marrow (2016): Mast cell infiltrate, +CD2/CD25 and +D816V					Ranitidine 150mg, cetirizine 10mg daily, cromolyn 200mg QID
7	M	56	Intermittent flushing, diarrhea, abdominal pain, pruritic rash, dyspnea and bone pain.	Baseline: 68.3 ug/L 107 ug/L	Mast cell infiltrate with atypical morphology, +CD2/CD25 and +D816V					Failed combination high dose H1 antagonists, H2 antagonists, montelukast 10mg daily, cromolyn 200mg QID and hydroxyurea 1000mg daily. Significant improvement with omalizumab

^*NMH: N-methylhistamine; LTE4: Leukotriene E4 ; PGF2: 11-β-Prostaglandin F2; PGD2: Prostaglandin D2; Nl: normal