This report describes food hypersensitivity in an 11 year old male who received Hep-B vaccine recombinant (Engerix-B). The reporter denied allergies and medical history. The pt took diphenhydramine hydrochloride (Benadryl) and fexofenadine hydrochloride (Allegra). On 9/26/00, the pt received his 1st dose of Engerix-B and 1 hours later, he experienced "food hypersensitivity" in the form of "tight throat" which later disappeared. No treatment was given. Reportedly, over the course of the next 2 weeks, the pt erupted into hives with some swelling of the lips, after eating foods to which he had never before been allergic. Additionally, he experienced headache and stomach ache whenever hives erupted. The pt was hospitalized. The reporter believed that these adverse events are related to Engerix-B. As of 5/4/01, the outcome of the events was ongoing. The pt was under the care of a pediatrician and an allergist. The vaccinee's mother refused to have the 2nd dose of Engerix-B administered. F/U has been partially verified by a physician. The pt was allergic to Ceclor and was according to the pediatrician was otherwise healthy. There were not concurrent medications. The pediatrician indicated that tightness of the throat occurred on 9/25/00, and resolved that day, He began to experience pruritis on 9/29/00, at that time his mother reported that. The pediatrician confirmed that hives began in 10/00, but did not confirm the headache, stomach ache, swelling of the lips or the dx of food hypersensitivity. The pediatrician reported that the pt experienced edema of the hands and feet. beginning on 10/30/00. The pt's mother reported that he was hospitalized this was not confirmed by the pediatrician. The following drugs were used to treat the hives and pruritis, fexofenadine hydrochloride (Allerga) from 10/31/00 to 11/00, diphenhydramine hydrochloride (benadryl) orally starting 11/00, cetirizine hydrochloride started 1/4/01, cimetidine twice daily started 5/01, montelukast sodium started 5/01. On 8/7/01, the pediatrician indicated that the tightness of throat was mild in intensity and had resolved. The pruritus, hives and edema of the hands and feet were moderate in intensity and ongoing. The pediatrician considered these events to be possibly related to Engerix-B administration. The pediatricain confirmed that the immunization series was discontinued. The pt was evaluated by a 2nd allergist on 3/28/01. At the time of the evaluation, the pt was taking Zyrtec daily. The allergist noed that after receiving Engerix-B, the pt returned from school and said I wish I hadn't had that shoe, it made my throat feel tight and very uncomfortable. The allergist wrote, this apparently disappeared in hrs or less. Over the following 2 wks he complained that his ankles and feet itched. This info was obtained in retrospect. Two weeks to the day after the vaccine administration he began to develop urticaria. He has had urticaria and angioedema since waxing and waning... The urticaria was raised, irregular in size, non blistered, not hemorhagic, and markedly pruritis. The angioedema was confined to the lips and on several occasions apparently to the hands and feet, this needs clarification. At on time there was visible tongue swelling. Maximum symptoms were in the months of Oct, Nov and early Dec. treatment: emergency room visit in nov., 4 months ago, given andIV injection of steroids. He then had a eriod of 2 weeks without symptoms. Symptoms tended to be present at night.worked up by (a different allergist). skin test for food said to be neg. The pt is otherwise well. He has had no difficulty with his medications. The mother questions whether benadryl works. She is convinced that there is a correlation between his change in immune system and the onset of uticaria. Family history: the mother is allergic, Physican exam: neg, Inpression: chronic urticaria, idiopathic, possibly related to hepatitis B vaccine.The allergist prescribed Zyretec daly and cimetidine twice daily. The pt was seen by the 2nd allergist on 4/17/01. He wrote the pt is doing extremely well. Now asymptomatic. It was noted that his pt has a protective titer of 19. The pt wa seen again by the 2nd allergist on 5/9/01. His medications included zyrtec, cimetidine, and epinephrine (epiPen) as needed. Teh allergist wrote, His symptoms have waxed and waned. initiall he did well with the zyrtec, but he has had breakthrough and despite an increase in medication. He continues to have symptoms all days. his rash is basically the same, waxing and waning. Pruritus is very well controlled ... workup to date has been negative. including cbc, ana liver function test, and compliment. a TSH is awaited his hepatitis B level is 19 which is high. Note he has had no respiratory problems. The allergist prescribed zyrec, cimetidine and singulair daily. The 2nd allergist saw the pt on 7/10/01 and wrote his chronic urticaria persists. The pt has symptoms almost all days, usually mild scattered on his trunk, non pruritic. Within the last 2 wks he has had a fairly severe episode with generalized urticaria. He may have had a little throat discomfot. The urticaria lasted for about 16 hrs. He was given benadryl backup and the itching quickly disappeared ...physical exam skin a few scattered lesions, raised on trunk, probably 10 in all. Lab work still showed little question of a slightly elevated T3. The allergist prescribed same meds as before. F/U 9/18/01 the most recent info was rec'd from the 2nd allergist. He reported tha the pt began to experience vague throat symptoms and pruritus on 9/26/00, and chronic urticaria began 10/10/00. He wrote, patient has chronic urticaria which has required careful manipulation to control. He is now reasonably controlled on zyrtec 25mg,singulair 10mg, and cimetidine 150mg, He has very mild hives daily. Pt doing well. He indiated that the chronic urticaria is possibly related to Engerix-B vaccine. The most recent info was received from the vaccinee's mother on 11/16/2001. At that time, the vaccinee was reportedly experiencing hives and swelling of his hands and feet daily. The events were being treated with Zyrtec, cimetidine and Singulair.