Allergy To Sheep's And Goat's Milk Cheese With Good Tolerance to Cow's Milk

Abstract

RATIONALE: Cow's milk (CM) allergy is common in children, although there are few reports of allergy to sheep's (SM) and goat's milk (GM) and with good tolerance to CM. METHODS: Patients: 2 y.o. female and a 10 y.o. male who presented inmediate systemic allergic reactions after ingestion of sheep's cheese and another cheese of unknown origin, respectively. Both patients have always tolerated cow's milk.Skin prick test, CAP-FEIA and immunoblotting were performed. RESULTS: Patient 1:Prick test (PT):CM, BSA, ALA and BLG: negative. Prick-prick (PPmm): SM (15), GM (13), cow's casein (CC) (3), sheep's casein (SC) (8), goat's casein (GC) (5). Specific IgE (CAP kU/L): CM:0.53, CC:0.79, SM:81.90; GM >100; BSA, ALA and BLG:<0,35. . Patient 2: PT: CM(3), BSA, BLG and ALA: negative. PP: SM(18), GM(12), CC(3), SC(8), GC(8). CAP: CM:2,75, CC:2.94, SM >100, GM>100; ALA, and BLG< 0.35. Both patients had strong IgE-binding to a protein with a MW about 31 kDa in SM, GM, SC and GC extracts. Both patients had weak IgE-binding to other proteins in a range of 19-60 kDa in SM and GM. Patient 2 show weak IgE-binding to other proteins in a range of 19- 60 kDa in CM, SC and GC. Serum from patient 1 did not recognize any band in CM or CC. CONCLUSIONS: An IgE-mediated allergy to sheep's and goat's milk was demonstrated in two patients without allergy to cow's milk. Sheep's and goat's casein seem to be the main allergen in these cases.