Recurrent Anaphylaxis Due to Delayed Allergy to Mammalian Meat in a Patient with Mastocytosis

Abstract

RationaleMastocytosis and delayed allergy to mammalian meat are under-recognized and potentially life-threatening conditions. We describe a patient with mastocytosis and delayed allergy to mammalian meat whose diagnoses came to light after several episodes of severe anaphylaxis.MethodsMeasurement of serum tryptase and IgE to galactose-alpha-1,3-galactose (alpha-gal) were performed at Mayo Clinic, Rochester, MN. Bone Marrow biopsy was performed at Barnes-Jewish Hospital, St. Louis, MO.ResultsA 52-year-old man presented with a several year history of recurrent syncope. Symptoms proceeding syncope included nausea, vomiting, abdominal cramping, flushing, itching and lightheadedness. Prolonged unresponsiveness, hypotension and bradycardia accompanied each event, once requiring intubation and mechanical ventilation. Cardiac work-up was unrevealing. A pacemaker was placed for presumed symptomatic sinus bradycardia. Detailed history later revealed ingestion of beef and pork several hours prior to each event, as well as exposure to tick bites. IgE to alpha-gal was 1.93 kU/L (reference range <0.35kU/L), suggesting that an allergy to alpha-gal triggered these events. Baseline serum tryptase was 30 ng/mL (reference range <11.5ng/mL) and bone marrow biopsy was diagnostic for mastocytosis. The patient was prescribed an epinephrine auto-injector, placed on cetirizine, ranitidine and montelukast, and instructed to limit exposure to ticks and mammalian meat. The patient has had no further episodes.ConclusionsWe believe this is one of the first cases described of life-threatening anaphylaxis secondary to delayed allergy to mammalian meat in a patient with mastocytosis. This case highlights the importance of including these rare entities in the differential diagnosis of unexplained syncope. RationaleMastocytosis and delayed allergy to mammalian meat are under-recognized and potentially life-threatening conditions. We describe a patient with mastocytosis and delayed allergy to mammalian meat whose diagnoses came to light after several episodes of severe anaphylaxis. Mastocytosis and delayed allergy to mammalian meat are under-recognized and potentially life-threatening conditions. We describe a patient with mastocytosis and delayed allergy to mammalian meat whose diagnoses came to light after several episodes of severe anaphylaxis. MethodsMeasurement of serum tryptase and IgE to galactose-alpha-1,3-galactose (alpha-gal) were performed at Mayo Clinic, Rochester, MN. Bone Marrow biopsy was performed at Barnes-Jewish Hospital, St. Louis, MO. Measurement of serum tryptase and IgE to galactose-alpha-1,3-galactose (alpha-gal) were performed at Mayo Clinic, Rochester, MN. Bone Marrow biopsy was performed at Barnes-Jewish Hospital, St. Louis, MO. ResultsA 52-year-old man presented with a several year history of recurrent syncope. Symptoms proceeding syncope included nausea, vomiting, abdominal cramping, flushing, itching and lightheadedness. Prolonged unresponsiveness, hypotension and bradycardia accompanied each event, once requiring intubation and mechanical ventilation. Cardiac work-up was unrevealing. A pacemaker was placed for presumed symptomatic sinus bradycardia. Detailed history later revealed ingestion of beef and pork several hours prior to each event, as well as exposure to tick bites. IgE to alpha-gal was 1.93 kU/L (reference range <0.35kU/L), suggesting that an allergy to alpha-gal triggered these events. Baseline serum tryptase was 30 ng/mL (reference range <11.5ng/mL) and bone marrow biopsy was diagnostic for mastocytosis. The patient was prescribed an epinephrine auto-injector, placed on cetirizine, ranitidine and montelukast, and instructed to limit exposure to ticks and mammalian meat. The patient has had no further episodes. A 52-year-old man presented with a several year history of recurrent syncope. Symptoms proceeding syncope included nausea, vomiting, abdominal cramping, flushing, itching and lightheadedness. Prolonged unresponsiveness, hypotension and bradycardia accompanied each event, once requiring intubation and mechanical ventilation. Cardiac work-up was unrevealing. A pacemaker was placed for presumed symptomatic sinus bradycardia. Detailed history later revealed ingestion of beef and pork several hours prior to each event, as well as exposure to tick bites. IgE to alpha-gal was 1.93 kU/L (reference range <0.35kU/L), suggesting that an allergy to alpha-gal triggered these events. Baseline serum tryptase was 30 ng/mL (reference range <11.5ng/mL) and bone marrow biopsy was diagnostic for mastocytosis. The patient was prescribed an epinephrine auto-injector, placed on cetirizine, ranitidine and montelukast, and instructed to limit exposure to ticks and mammalian meat. The patient has had no further episodes. ConclusionsWe believe this is one of the first cases described of life-threatening anaphylaxis secondary to delayed allergy to mammalian meat in a patient with mastocytosis. This case highlights the importance of including these rare entities in the differential diagnosis of unexplained syncope. We believe this is one of the first cases described of life-threatening anaphylaxis secondary to delayed allergy to mammalian meat in a patient with mastocytosis. This case highlights the importance of including these rare entities in the differential diagnosis of unexplained syncope.