Maize food allergy: a double-blind placebo-controlled study.

BACKGROUND: Maize allergy is not very common especially in Europe. The number of studies that address IgE mediated maize allergy is all too few. OBJECTIVE: Evaluate subjects with a history of maize allergy by double-blind, placebo-controlled food challenge; identify the spectrum of symptoms manifested during challenge; determine the lowest provocation dose (PD) during challenge; determine the performance characteristics of maize skin prick test and specific IgE. METHODS: Twenty-seven patients with a history of maize allergy were enrolled to be evaluated by skin test, specific IgE and double-blind placebo-controlled maize challenge. RESULTS: Forty-eight percent of the patients were challenge positive. PD range was 0.1-25 g. Fifty-four percent of the maize allergic subjects had a PD that was < or = 2.5 g; two subjects reacted to 100 mg of maize. Comparison of maize specific IgE levels and skin test results to the challenge results revealed the following (specific IgE level/skin testing): sensitivity 1.00/0.846, specificity 0.077/0.384, positive predictive value 0.520/0.579, and negative predictive value 1.00/0.714. CONCLUSION: Maize is a cause of IgE-mediated allergic reactions to foods in adults and children. Nearly half of the subjects recruited were confirmed by challenge to be allergic to maize. Twenty-three percent of the positive challenge patients manifested symptoms that involved two organ systems, thus fulfilling the criteria for maize induced anaphylaxis. Maize is allergenic and can pose a risk for symptomatic food allergy at a dose of 100 mg.

Hepatitis C virus serum markers and liver disease in children with leukemia during and after chemotherapy.

The pattern of hepatitis C virus (HCV) serum markers and liver disease was investigated in 11 leukemic children showing anti-HCV reactivity at least once during long-term observation to define the role of HCV infection and the behavior of HCV serologic markers in this patient cohort. Antibodies to HCV by first- and second-generation enzyme-linked immunosorbent assay (ELISA) and by second-generation (four antigens) recombinant immunoblotting assay (RIBA) and HCV-RNA by nested polymerase chain reaction (PCR) were serially examined in serum. Liver disease was defined according to transaminase levels. Seven of 11 patients were found HCV-RNA positive during chemotherapy and after blood transfusion, 3 of 11 became viremic during follow-up, and 1 of 11 was always HCV-RNA negative. Seroconversion to anti-HCV positivity by second-generation ELISA occurred in all the HCV-RNA positive children either during or after chemotherapy. Alanine aminotransferase (ALT) levels were elevated in all the HCV-RNA positive patients during antileukemic treatment and normalized in seven of them after therapy withdrawal, despite persisting viremia. These results indicate that HCV-RNA testing by polymerase chain reaction is required to correctly identify HCV infection in patients with leukemia while on chemotherapy. Viremia did not correlate with ALT levels and anti-HCV patterns.

High-dose methotrexate administration and acute liver damage in children treated for acute lymphoblastic leukemia. A prospective study.

BACKGROUND: Methotrexate-induced hepatotoxicity following chronic low-dose administration has been extensively reported. Current protocols now include high-dose methotrexate (HDMTX), but there are few studies providing data on its acute hepatotoxicity in childhood leukemia. METHODS: To evaluate the prevalence of HDMTX-induced acute hepatotoxicity, sixty-eight consecutive children with ALL were prospectively studied from diagnosis to the end of HDMTX courses with biochemical and clinical evaluation performed at regular intervals. RESULTS: Prevalence of HDMTX-induced acute hepatotoxicity was 1.47% (1/68 patients). ALT values did not change in 22% (15/68) and decreased in 76.4% (52/68) after HDMTX infusion. Mean ALT levels calculated in all the patients decreased significantly during HDMTX administration when compared to the values reached during induction (p less than 0.0001). Direct hyperbilirubinemia was present only in the child with HDMTX-related hepatotoxicity. CONCLUSIONS: The use of HDMTX in the treatment of childhood ALL is not associated with major evidence of direct acute hepatotoxic effects, while it may modify the pattern of preexisting liver diseases.