Anaphylaxis caused by lipid transfer proteins: an unpredictable clinical syndrome

INTRODUCTION: Lipid transfer proteins (LTPs) are panallergens found in many plant foods. They are a common cause of food-induced anaphylaxis (FIA) in adults living in the Mediterranean area. LTPs have also been proposed as a main cause of food-dependent exercise-induced anaphylaxis (FDEIA). OBJECTIVES: Describe clinical characteristics and allergen sensitization profiles in patients with FIA related to LTP. MATERIALS AND METHODS: Forty-three patients were included, aged 3-52 years with a clinical history of FIA and proven sensitization to LTP. Patients were tested with a multiple plant food and pollen panel and specific IgE to LTP allergens. LTP sensitization was assessed by in vivo (Pru p 3, LTP extract) and/or by in vitro tests (specific IgE, ImmunoCAP/ISAC(R)). RESULTS: Median age of first anaphylactic episode was 24 years (range 2-51), 44% had asthma, 74% were atopic and 42% had pollinosis (olive, mugwort, plane tree, wall pellitory and cypress). Co-sensitization to profilins was found in 22%. Overall in our center, LTP-induced anaphylaxis represents 17% of all causes of FIA. Foods implicated in anaphylactic reactions were: fresh fruits 51%, tree nuts 42%, vegetables (including peanut) 40% and seeds 14%. Seven patients had FDEIA. CONCLUSIONS: LTPs are important allergens of FIA in Portugal. Clinical reactivity to several taxonomically unrelated plant foods may raise suspicion toward LTP sensitization. The association of LTP-induced anaphylaxis with pollinosis is relevant in our country. The unpredictable clinical expression depends on the effect of cofactors such as exercise. The management of avoidance plans can be challenging due to LTP being a widely cross-reacting allergen in plant foods

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Anaphylaxis caused by lipid transfer proteins: an unpredictable clinical syndrome.

INTRODUCTION: Lipid transfer proteins (LTPs) are panallergens found in many plant foods. They are a common cause of food-induced anaphylaxis (FIA) in adults living in the Mediterranean area. LTPs have also been proposed as a main cause of food-dependent exercise-induced anaphylaxis (FDEIA). OBJECTIVES: Describe clinical characteristics and allergen sensitization profiles in patients with FIA related to LTP. MATERIALS AND METHODS: Forty-three patients were included, aged 3-52 years with a clinical history of FIA and proven sensitization to LTP. Patients were tested with a multiple plant food and pollen panel and specific IgE to LTP allergens. LTP sensitization was assessed by in vivo (Pru p 3, LTP extract) and/or by in vitro tests (specific IgE, ImmunoCAP/ISAC®). RESULTS: Median age of first anaphylactic episode was 24 years (range 2-51), 44% had asthma, 74% were atopic and 42% had pollinosis (olive, mugwort, plane tree, wall pellitory and cypress). Co-sensitization to profilins was found in 22%. Overall in our center, LTP-induced anaphylaxis represents 17% of all causes of FIA. Foods implicated in anaphylactic reactions were: fresh fruits 51%, tree nuts 42%, vegetables (including peanut) 40% and seeds 14%. Seven patients had FDEIA. CONCLUSIONS: LTPs are important allergens of FIA in Portugal. Clinical reactivity to several taxonomically unrelated plant foods may raise suspicion toward LTP sensitization. The association of LTP-induced anaphylaxis with pollinosis is relevant in our country. The unpredictable clinical expression depends on the effect of cofactors such as exercise. The management of avoidance plans can be challenging due to LTP being a widely cross-reacting allergen in plant foods.

Ultrarush schedule of subcutaneous immunotherapy with modified allergen extracts is safe in paediatric age.

BACKGROUND: Traditional subcutaneous immunotherapy up dosing with allergenic extracts has been shown to be associated with frequent adverse reactions. In recent studies it has been demonstrated that using modified extracts, namely allergoids, it is a safe and effective procedure particularly on accelerated schedules. However data assessing its safety in paediatric age is scarce. OBJECTIVE: To evaluate the safety profile in paediatric population of using modified allergen extracts, in an ultrarush schedule, to reach the maintenance dose in the first day. METHODS: We included children undergoing treatment with subcutaneous immunotherapy during a five-year period, using modified aeroallergen extracts, depigmented, polymerized with glutaraldehyde and adsorbed on aluminium hydroxide using an ultrarush induction phase. The type of adverse reactions during the ultrarush protocol was recorded. RESULTS: We studied 100 paediatric patients (57 males) with a mean age of 11.6 years (5 to 18 years; standard deviation, 3.3), all with moderate to severe persistent rhinitis, with or without allergic conjunctivitis, asthma and atopic eczema, sensitized to mites and/or pollens. All reached the maintenance dose of 0.5 mL in the first day, except 1 child. During the ultrarush protocol the total number of injections was 199. There were 21 local adverse reactions in 11 patients, 11 immediate and 10 delayed; from those, had clinical relevance 1 immediate and 4 delayed. Systemic reactions were recorded in 2 cases, both immediate and mild. CONCLUSION: The ultrarush protocol, without premedication, was a safe alternative to be used in paediatric age during the induction phase of subcutaneous immunotherapy using allergoid depigmented extracts.

Risk factors for asthma admissions in children.

Bronchial asthma is related to a high morbidity rate, leading to an increasing frequency of emergency room visits and hospital admissions. The aim of this study was to identify severity risk factors for childhood asthma related to hospitalization. The authors studied 124 children admitted to the hospital for asthma, during a 2-year period, correlating the obtained data with a sample of outpatients with asthma matched by age, gender, and socioeconomic status. A standardized questionnaire and skin-prick tests (SPTs) were performed on all children. The significant and independent risk factors identified for hospital admission were prior asthma hospitalization (OR = 7.63; 95% CI = 1.5-39.6; p = 0.01) and last-year admission (OR = 3.18; 95% CI = 1.1-8.9; p = 0.02), environmental tobacco-smoke exposure (OR = 6.63; 95% CI = 2.5-17.8; p = 0.002), allergen sensitization (OR = 3.86; 95% CI = 1.4-10.7; p = 0.009), family history of maternal asthma (OR = 3.58; 95% CI = 1.3-9.6; p = 0.01), and onset of symptoms before 12 months of age (OR = 2.76; 95% CI = 1.0-7.9; p = 0.06). Attendance at day care or kindergarten (OR = 0.38; 95% CI = 0.2-0.9; p = 0.04) and large family size (OR = 0.25; 95% CI = 0.1-0.8; p = 0.01) could be protective factors. Our results stress the importance of early diagnosis and specialized medical care of childhood asthma, mainly in high-risk children, with emphasis on medication planning and the establishment of preventive measures such as environmental tobacco smoke avoidance and limitation of aeroallergen exposure.