A rare presentation of mammalian milk anaphylaxis in adults

Abstract

Cow’s milk (CM) allergy is the most prevalent food allergy in children but is very rare in adults. We describe an unusual case of a patient who became allergic to CM and other mammalian milks, during her adult life, with anaphylaxis, and whom successfully underwent a CM oral immunotherapy (OIT). A 43 years-old women was referred to our Immunoallergy department in 2018 with a history of several anaphylactic episodes since 2011. All episodes are characterized by pruritus, generalized erythema and angioedema, and dyspnea. The first reaction occurred immediately after eating cheese with goat (GM) and sheep milks (SM). Since then, she started to evict every sort of milk/derivates. Four years later, she had a reaction after a corticosteroid administration with traces of CM. In 2017, she had another reaction immediately after eating a salad contaminated by cheese. She has a past history of asthma and rhinosinusitis with nasal polyps, but she had never been allergic to any food. In 2005, during her son breastfeeding (9 months), she underwent a rigorous eviction of CM/derivates because of his atopic dermatitis. Between 2006-2011 she reported several episodes of oropharyngeal tightening after eating foods containing CM. Skin-prick tests (Roxall®) to CM and proteins extracts were positive to casein-4x4mm, α-lactoalbumin-5x6mm and β-lactoglobulin-3x4mm. Prick by prick tests were positive to CM-7x7mm, GM-5x6mm and SM-5x5mm. Specific IgEs (UniCAP,ThermoFisher®) were found to GM-0,36 kU/l, SM-0,29 kU/l, CM-0,55 kU/l, casein-6,48 kU/l, α-lactoalbumin-0,34 kU/l and β-lactoglobulin-0,04 kU/l. She was successfully submitted to a CM-OIT protocol, reaching a daily dose of 200ml in 4 months (7 sessions). She had several mild adverse reactions, all with spontaneous resolution. Currently, she completed 6 months of the maintenance phase, with a free diet for CM, and a significant improvement in her quality of life. It was proposed an OIT for GM or SM but she refused for the moment. To our knowledge, this is the first case report of a patient who became sensitized to CM proteins in adult life who successfully underwent a CM OIT protocol. The patterns of allergy are changing, with the appearance, in adulthood, of severe food allergies characteristically associated with childhood. CM-OIT is a safe and effective treatment for severe and long-lasting CM allergy. The protocol used allowed to achieve tolerance within a short period of time. Maintenance of 200 mL daily ingestion enables a diet without restrictions, with a clear positive impact on the quality of life.