Akiko Morita

Correlation of oral allergy syndrome due to plant-derived foods with pollen sensitization in Japan

BACKGROUND The clinical features of patients with oral allergy syndrome (OAS) due to plant-derived foods related to pollen allergy have been rarely reported in Japan. OBJECTIVES To evaluate the characteristics of OAS and to investigate whether pollen sensitizations are correlated with the prevalence of OAS in Japan. METHODS We measured specific IgE antibodies against 5 pollens in 622 outpatients (277 males and 345 females; mean age, 37 years) with atopic dermatitis, urticaria, angioedema, and food allergy during a 2-year period. Furthermore, OAS is diagnosed based on anamnesis and positive skin prick test reactions to suspected foods. RESULTS Eighteen of the 436 patients (4.1%) sensitized to pollens were diagnosed as having OAS. Rates of specific IgE antibody-positive responses against Japanese cedar, ragweed, orchard grass, mugwort, and alder pollen were 69.8%, 35.3%, 29.1%, 24.1%, and 19.6%, respectively. The prevalence of OAS showed a significant positive correlation with sensitization to alder (P < .001). In addition, the most frequent causative foods were found to be apple, peach, and melon. The prevalence of OAS due to apple showed a significant positive correlation with sensitization to alder (P < .001) pollen, due to peach showed a significant positive correlation with sensitization to alder (P < .001) and orchard grass (P < .05) pollen, and due to melon showed a significant positive correlation with sensitization to alder (P < .005), orchard grass (P < .05), and ragweed (P < .05) pollen. CONCLUSION Sensitization to pollens from species in the Betulaceae family is most strongly implicated in causing OAS in Japan.

Clinical Features of Four Cases with Cashew Nut Allergy and Cross-Reactivity between Cashew Nut and Pistachio

BACKGROUND Few cases of cashew nut (CN) allergy have been reported in Japan. We evaluated the clinical features of 4 cases with CN allergy and investigated the allergens involved. METHODS In order to investigate the cross-reactivity between CN and pistachios, we performed ImmunoCAP inhibition tests using sera of 4 cases with positive histories of CN allergy and positive results of specific IgE measurement (ImmunoCAP) and skin prick tests. Furthermore, we analyzed the molecular weights of allergens of CN and pistachios by IgE-immunoblotting. RESULTS Of the 4 cases (male : female = 1:3), there were 3 cases (patient #2-4) and 1 case (patient #1) of anaphylaxis and oral allergy syndrome, respectively. The initial symptom was an oropharyngeal symptom in 3 of the 4 cases, of which 2 cases developed anaphylaxis within 10 minutes after eating only a few pieces of CN. All 4 cases reacted positively to the skin prick test with CN, although 1 case of anaphylaxis tested negatively for CN by ImmunoCAP. Additionally, in 2 cases, IgE-binding to CN and pistachio were inhibited with both pistachios and CN, indicating cross-reactivity between CN and pistachios. IgE-immunoblotting of CN using sera from the 4 cases revealed 2 bands at molecular weights of approximately 33 kd and 42 kd, whereas that of pistachios showed a single band at 36 kd. However, IgE in all 4 sera did not bind to rAna o 2. CONCLUSIONS In CN allergy, a small amount of CN could induce a severe anaphylactic reaction. Moreover, in cases of suspected CN allergy, reactions to not only CN but also pistachio, which could be cross-reactive to CN, should be examined.

A case of toxic epidermal necrolysis induced by allopurinol with human herpesvirus-6 reactivation.

Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and drug-induced hypersensitivity syndrome (DIHS) or drug rash with eosinophilia and systemic symptoms (DRESS) (1, 2) are severe adverse drug reactions (ADRs). Recently, human herpesvirus 6 (HHV-6) reactivation has been observed frequently in patients with DIHS/DRESS, but not in SJS/TEN (3–5). Therefore, it has been suggested that HHV-6 is closely related to the pathogenesis of DIHS, but not to that of SJS/TEN (6, 7). We report here a case of TEN induced by allopurinol, accompanied by HHV-6 reactivation.

Case of rice allergy induced by epicutaneous sensitization to rice bran due to handling rice bran pickles

Dear Editor, There have been several reports of immunoglobulin (Ig) Emediated reactions following contact with raw rice, inhalation of vapors from boiling rice and ingestion of cooked rice. However, rice bran allergy has never been reported. In this report, we describe the first case of occupational contact urticaria in a housewife due to the handling of rice bran in the form of rice bran pickles; this initial reaction was followed by allergic reactions after the ingestion of cooked, unpolished and unwashed rice in paella. A 50-year-old Japanese housewife was referred to our clinic for a history of oral itch, face angioedema and cough after the ingestion of paella while travelling in Spain. She had begun pickling vegetables in rice bran paste 3 years previously. However, 6 months previously, she developed wheals and itch on the hands and forearms, while handling rice bran paste. Thereafter, she also felt oral itch after the ingestion of rice bran pickles and cooked, unpolished rice. Furthermore, wheals on the hands had developed during the washing of raw polished rice, although she regularly consumed polished rice, which was cooked after washing, without symptoms. Her past history included pollinosis due to Japanese cedar pollen but not to grass pollen. Serum total IgE level was 652 IU/mL. The specific IgE measurements using the ImmunoCAP system (Phadia, Uppsala, Sweden) showed positive for rice, which was extracted from unpolished rice, wheat, barley and rye, whereas they were negative for ingredients of paella, such as shrimp, squid and scallop. The elicited response of skin prick tests (SPT) was considered positive when the average wheal diameter induced by the allergen was 50% of the positive control response induced by histamine chloride at 10 mg/mL. SPT with commercial extracts (Torii Pharmaceutical, Tokyo, Japan) for rice and wheat were positive. SPT with rice bran at 0.2 g/mL in saline, and unpolished and polished rice at 0.5 g/mL in saline were also positive. Additionally, the average wheal diameter (17.8 mm) induced by polished rice was diminished by washing (8.4 mm) and cooking (7.9 mm). The SPT with extracts of rice bran, unpolished and polished rice was negative in five control subjects. In IgE immunoblotting, IgE binding at approximately 50 kDa was shown by the serum of the patient, whereas not by two controls without rice allergy (Fig. 1). Rice bran is the layer between the inner white rice grain and the outer hull and is a by-product of the rice polishing process. Rice bran is used for foods and skin care products such as soap in not only Asian countries but also westernized nations because it is rich in vitamins and minerals. Rice bran pickles, nukazuke, are a traditional Japanese food. This patient first developed IgE-mediated contact urticaria due to rice bran during pickling vegetables in rice bran paste. Furthermore, continuous skin exposure to rice bran while dealing with rice bran pickles and washing rice was found to result in allergic reactions after ingestion of cooked, unpolished rice and unwashed rice, such as that found in paella. Contact urticaria to rice while handling raw rice or throwing it during weddings has been reported in both Southern Europe and Japan. The relevant allergens in rice causing contact urticaria have never been identified, although several allergenic components in rice have been described, including Ory s 1 (35 kDa), a 14–16-kDa member of the a-amylase/trypsin inhibitor family, a 33-kDa allergen with glyoxalase I activity, and a 9-kDa lipid transfer protein. The molecular weight of the allergen involved in rice bran allergy in this patient was 50 kDa, indicating that the allergen involved in epicutaneous sensitization of rice bran can be different from the inhalant and food rice allergens reported. Additionally, in SPT, cooked rice induced much smaller wheals than uncooked rice, indicating that the rice bran allergens could be unstable during heating.