Eosinophilia and gastrointestinal symptoms after ingestion of shiitake mushrooms.

BACKGROUND: Shiitake mushrooms are a dietary staple in Asia and are increasingly popular worldwide. A cholesterol-lowering study with shiitake showed that 17 of 49 participants withdrew because of rash or abdominal discomfort, and two had marked eosinophilia. One of these latter participants was subsequently challenged for 14 days with shiitake powder and again had eosinophilia. OBJECTIVE: We investigated whether ingestion of shiitake mushroom powder induces eosinophilia or symptoms. METHODS: We studied 10 normal persons. Each participant ingested 4 gm shiitake powder (open label) daily for 10 weeks (trial 1), and the protocol was repeated in these same subjects after 3 to 6 months (trial 2). Blood counts and serum samples were obtained biweekly (trial 1) or weekly along with stool specimens (trial 2). Eosinophil major basic protein and IL-5, IgE, and IgG antishiitake antibodies were measured in sera. Eosinophil-derived neurotoxin was measured in stool extracts. We defined responders as subjects having peak eosinophil counts four or more times their average baseline counts. RESULTS: Each trial had four responders, and trial 2 had one new and three repeat responders. Eosinophilia ranged from 400 to 3900/mm3. Responders had increased blood eosinophils, serum major basic protein, stool eosinophil-derived neurotoxin, and factors that enhanced eosinophil viability. Antishiitake IgE was not detected, and antishiitake IgG increased in two responders. Gastrointestinal symptoms coincided with eosinophilia in two subjects. Symptoms and eosinophilia resolved after discontinuing shiitake ingestion. CONCLUSIONS: Daily ingestion of shiitake mushroom powder in five of 10 healthy persons provoked blood eosinophilia, increased eosinophil granule proteins in serum and stool, and increased gastrointestinal symptoms. Shiitake ingestion suggests a model to study the eosinophil's role in the blood and gastrointestinal tract. Finally, our report raises concerns of possible adverse systemic reactions to this increasingly popular food.

Latex-induced asthma in a dental assistant.

In this case report, latex-induced asthma is described in a dental assistant with an associated history of contact dermatitis, contact urticaria, and rhinitis. She switched to vinyl gloves, which eliminated her cutaneous symptoms, but her respiratory symptoms continued. Skin-testing to latex was strongly positive. Methacholine challenge and peak expiratory flow rates (PEFR) were abnormal during the workweek but normalized after a two-week vacation. Nebulized latex was implicated in the development of occupational asthma, and personal latex-avoidance measures did not prevent the condition.