Can conjunctival provocation test facilitate the diagnosis of food allergy in children?

Background: Food allergy is common in children, occurring in 5–7.5%. The diagnosis may, however, be difficult. Elevated IgE or positive skin prick test to a food allergen is often considered proof of allergy, but may represent sensitisation without clinical manifestations. For a precise diagnosis oral challenge is necessary, but this is often not performed because of risk of serious allergic reactions. The aim of this study was to evaluate whether conjunctival provocation test would facilitate the diagnosis of IgE-mediated food allergy. Methods: One hundred and forty-nine children with 174 possible diagnoses of food allergy were included. General examination, skin prick test and specific IgE were performed, as well as conjunctival provocation test of the suspected food allergen. Open food challenges and double-blind placebo controlled tests were performed in order to diagnose possible food allergy. Results: Forty-six children with strongly positive conjunctival reactions (rubor, itching, oedema) to fifty food allergens were all proven to have allergy to the food in question. The children with negative conjunctival provocation tests showed no allergic reactions when challenged. Conclusions: We find that a strongly positive conjunctival reaction to a food allergen correlates well with true allergy. An oral challenge should be carefully performed. With a negative conjunctival test an oral challenge may safely be performed

Can conjunctival provocation test facilitate the diagnosis of food allergy in children?

BACKGROUND: Food allergy is common in children, occurring in 5-7.5%. The diagnosis may, however, be difficult. Elevated IgE or positive skin prick test to a food allergen is often considered proof of allergy, but may represent sensitisation without clinical manifestations. For a precise diagnosis oral challenge is necessary, but this is often not performed because of risk of serious allergic reactions. The aim of this study was to evaluate whether conjunctival provocation test would facilitate the diagnosis of IgE-mediated food allergy. METHODS: One hundred and forty-nine children with 174 possible diagnoses of food allergy were included. General examination, skin prick test and specific IgE were performed, as well as conjunctival provocation test of the suspected food allergen. Open food challenges and double-blind placebo controlled tests were performed in order to diagnose possible food allergy. RESULTS: Forty-six children with strongly positive conjunctival reactions (rubor, itching, oedema) to fifty food allergens were all proven to have allergy to the food in question. The children with negative conjunctival provocation tests showed no allergic reactions when challenged. CONCLUSIONS: We find that a strongly positive conjunctival reaction to a food allergen correlates well with true allergy. An oral challenge should be carefully performed. With a negative conjunctival test an oral challenge may safely be performed.

Atopic dermatitis in premature and term children.

OBJECTIVE: To investigate the prevalence of atopic dermatitis (AD) in premature compared with term children, the frequency of food allergy in children with AD, and the possible differences in prevalence of AD in children delivered by caesarean section compared with vaginally delivered children. DESIGN: Prospective follow-up study over 2 years. METHOD: 609 children (193 premature and 416 term) were included. At 2 years, 512 children (161 premature and 351 term) participated. Children with symptoms consistent with AD/possible food allergy were examined, and the dermatitis was evaluated according to the SCORAD index. Skin prick test, specific IgE, elimination/challenge and DBPC challenge were performed. RESULTS: 18.6% (95/512) of the children (19.9% (32/161) premature and 17.9% (63/351) term) had a diagnosis of AD. The prevalence of adverse reactions to food in all the children with AD was 15.8% (15/95) (similar in preterm and term children). AD was found in 17.5% (30/171) of children delivered by caesarean section, and 19.1% (65/341) delivered vaginally CONCLUSIONS: The prevalence of AD in the first 2 years of life was 18.6%, with no significant difference between preterm and term children. Adverse reactions to food were found in 15.8% (a similar prevalence in premature and term children). Mode of delivery did not affect prevalence of AD.

Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparison.

BACKGROUND: The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain. We aimed to assess the sensitivity of these three imaging tests. METHODS: Patients with faecal occult blood, haematochezia, iron-deficiency anaemia, or a family history of colon cancer underwent three separate colon-imaging studies--ACBE, followed 7-14 days later by CTC and colonoscopy on the same day. The primary outcome was detection of colonic polyps and cancers. Outcomes were assessed by building an aggregate view of the colon, taking into account results of all three tests. FINDINGS: 614 patients completed all three imaging tests. When analysed on a per-patient basis, for lesions 10 mm or larger in size (n=63), the sensitivity of ACBE was 48% (95% CI 35-61), CTC 59% (46-71, p=0.1083 for CTC vs ACBE), and colonoscopy 98% (91-100, p<0.0001 for colonoscopy vs CTC). For lesions 6-9 mm in size (n=116), sensitivity was 35% for ACBE (27-45), 51% for CTC (41-60, p=0.0080 for CTC vs ACBE), and 99% for colonoscopy (95-100, p<0.0001 for colonoscopy vs CTC). For lesions of 10 mm or larger in size, the specificity was greater for colonoscopy (0.996) than for either ACBE (0.90) or CTC (0.96) and declined for ACBE and CTC when smaller lesions were considered. INTERPRETATION: Colonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests.

Videofluoroscopic evaluation of HIV/AIDS patients with swallowing dysfunction.

BACKGROUND: We investigated the association of abnormalities of the swallowing mechanism in the oral and pharyngeal phases of swallowing with symptoms of dysphagia and painful swallowing in patients with human immunodeficiency virus (HIV). METHODS: Seventeen patients, two with HIV and 15 with acquired immunodeficiency syndrome (AIDS), with symptoms of dysphagia or pain on swallowing for routine barium esophagograms were studied prospectively by videofluoroscopic examination of the oropharynx in addition to a routine biphasic esophagogram. The videofluoroscopic studies were performed in conjunction with a speech pathologist. RESULTS: All 17 patients demonstrated abnormalities in the oral, pharyngeal, or esophageal phase of swallowing. Eight patients aspirated, six of whom did not exhibit a cough reflex and were classified as silent aspirators. Seven of the eight patients who aspirated had chest radiographs consistent with aspiration pneumonia. CONCLUSION: A significant number of HIV-positive and AIDS patients with dysphagia or pain on swallowing have dysfunction of the swallowing mechanism and are at risk for aspiration.

Poor CD4 T cell restoration after suppression of HIV-1 replication may reflect lower thymic function.

OBJECTIVE: To characterize immune phenotype and thymic function in HIV-1-infected adults with excellent virologic and poor immunologic responses to highly active antiretroviral therapy (HAART). METHODS: Cross-sectional study of patients with CD4 T cell rises of > or = 200 x 10(6) cells/l (CD4 responders; n = 10) or < 100 x 10(6) cells/l (poor responders; n = 12) in the first year of therapy. RESULTS: Poor responders were older than CD4 responders (46 versus 38 years; P < 0.01) and, before HAART, had higher CD4 cell counts (170 versus 35 x 106 cells/l; P = 0.11) and CD8 cell counts (780 versus 536 x 10(6) cells/l; P = 0.02). After a median of 160 weeks of therapy, CD4 responders had more circulating naive phenotype (CD45+CD62L+) CD4 cells (227 versus 44 x 10(6) cells/l; P = 0.001) and naive phenotype CD8 cells (487 versus 174 x 10(6) cells/l; P = 0.004) than did poor responders (after 130 weeks). Computed tomographic scans showed minimal thymic tissue in 11/12 poor responders and abundant tissue in 7/10 responders (P = 0.006). Poor responders had fewer CD4 cells containing T cell receptor excision circles (TREC) compared with CD4 responders (2.12 versus 27.5 x 10(6) cells/l; P = 0.004) and had shorter telomeres in CD4 cells (3.8 versus 5.3 kb; P = 0.05). Metabolic labeling studies with deuterated glucose indicated that the lower frequency of TREC-containing lymphocytes in poor responders was not caused by accelerated proliferation kinetics. CONCLUSION: Poor CD4 T cell increases observed in some patients with good virologic response to HAART may be caused by failure of thymic T cell production.

The effects of recombinant human growth hormone on body composition and glucose metabolism in HIV-infected patients with fat accumulation.

GH has been proposed as a therapy for patients with HIV-associated fat accumulation, but the pharmacological doses (6 mg/d) used have been associated with impaired fasting glucose and hyperglycemia. In contrast, physiologic doses of GH ( approximately 1 mg/d) in HIV-negative men reduced visceral adiposity and eventually improved insulin sensitivity, despite initially causing insulin resistance. We conducted an open-label study to evaluate the effects of a lower pharmacologic dose of GH (3 mg/d) in eight men with HIV-associated fat accumulation. Oral glucose tolerance, insulin sensitivity, and body composition were measured at baseline, and 1 and 6 months. Six patients completed 1 month and 5, 6 months of GH therapy. IGF-I levels increased 4-fold within 1 month of GH treatment. Over 6 months, GH reduced buffalo hump size and excess visceral adipose tissue. Total body fat decreased (17.9 +/- 10.9 to 13.5 +/- 8.4 kg, P = 0.05), primarily in the trunk region. Lean body mass increased (62.9 +/- 6.4 to 68.3 +/- 9.1 kg, P = 0.03). Insulin-mediated glucose disposal, measured by a euglycemic hyperinsulinemic clamp, declined at month 1 (49.7 +/- 27.5 to 25.6 +/- 6.6 nmol/kg(LBM).min/pmol(INSULIN)/liter, P = 0.04); values improved at month 6 (49.2 +/- 22.6, P = 0.03, compared with month 1) and did not differ significantly from baseline. Similarly, the integrated response to an oral glucose load worsened at month 1 (glucose area under the curve 20.1 +/- 2.3 to 24.6 +/- 3.7 mmol.h/liter, P < 0.01), whereas values improved at month 6 (22.1 +/- 1.5, P = 0.02, compared with month 1) and did not differ significantly from baseline. One patient developed symptomatic hyperglycemia within 2 wk of GH initiation; baseline oral glucose tolerance testing revealed preexisting diabetes despite normal fasting glucose. In conclusion, GH at 3 mg/d resulted in a decrease in total body fat and an increase in lean body mass in this open-label trial. While insulin sensitivity and glucose tolerance initially worsened, they subsequently improved toward baseline. However, the dose of GH used in this trial was supraphysiologic and led to an increase in IGF-I levels up to three times the upper normal range. Because there are known adverse effects of long-term GH excess, the effectiveness of lower doses of GH should be studied. We also recommend a screening oral glucose tolerance test be performed to exclude subjects at risk for GH-induced hyperglycemia.

Metabolic effects of indinavir in healthy HIV-seronegative men.

BACKGROUND: Therapy with HIV protease inhibitors (PI) has been associated with hyperglycemia, hyperlipidemia and changes in body composition. It is unclear whether these adverse effects are drug related, involve an interaction with the host response to HIV or reflect changes in body composition. METHODS: Indinavir 800 mg twice daily was given to 10 HIV-seronegative healthy men to distinguish direct metabolic effects of a PI from those related to HIV infection. Fasting glucose and insulin, lipid and lipoprotein profiles, oral glucose tolerance (OGTT), insulin sensitivity by hyperinsulinemic euglycemic clamp, and body composition were measured prior to and after 4 weeks of indinavir therapy. RESULTS: Fasting glucose (4.9 +/- 0.1 versus 5.2 +/- 0.2 mmol/l; P = 0.05) insulin concentrations (61.7 +/- 12.2 versus 83.9 +/- 12.2 pmol/l; P < 0.05), insulin : glucose ratio (12.6 +/- 1.7 versus 15.9 +/- 1.9 pmol/mmol; P < 0.05) and insulin resistance index by homeostasis model assessment (1.9 +/- 0.3 versus 2.8 +/- 0.5;P < 0.05) all increased significantly. During OGTT, 2 h glucose (5.1 +/- 0.4 versus 6.5 +/- 0.6 mmol/l; P < 0.05) and insulin levels (223.1 +/- 48.8 versus 390.3 +/- 108.8 pmol/l;P =0.05) also increased significantly. Insulin-mediated glucose disposal decreased significantly (10.4 +/- 1.4 versus 8.6 +/- 1.2 mg/kg x min per microU/ml insulin; 95% confidence interval 0.6--.0;P < 0.01). There was no significant change in lipoprotein, triglycerides or free fatty acid levels. There was a small loss of total body fat (15.8 +/- 1.4 versus 15.2 +/- 1.4 kg;P = 0.01) by X-ray absorptiometry without significant changes in weight, waist : hip ratio, and visceral or subcutaneous adipose tissue by computed tomography. CONCLUSIONS: In the absence of HIV infection, treatment with indinavir for 4 weeks causes insulin resistance independent of increases in visceral adipose tissue or lipid and lipoprotein levels.

Comparison of patients' experiences during imaging tests of the colon.

BACKGROUND: Physical discomfort, anxiety, embarrassment, and other aspects of patient experience impact on future compliance for colonic imaging tests. Therefore, a prospective study was performed comparing patient experiences during air contrast barium enema (ACBE), flexible sigmoidoscopy, and colonoscopy. METHODS: Immediately after each procedure, patients completed a questionnaire assessing pretest anxiety, difficulty with preparation, pain, cramping, bloating, overall discomfort, loss of dignity, willingness to repeat the test, and overall satisfaction. A follow-up questionnaire was administered within 48 hours. Nurses and physicians also completed questionnaires to assess the provider impression of patient experience. RESULTS: Four hundred ten patients (80 ACBE, 202 sigmoidoscopy, 128 colonoscopy) were prospectively enrolled. Sigmoidoscopy caused more pain than ACBE (Odds ratio [OR] 2.64: 95% CI [1.63, 4.27]) or colonoscopy (OR 1.83: 95% CI [1.21, 2.77]). ACBE and colonoscopy did not differ in the degree of pain. Although overall satisfaction appeared to be similar for all tests, patients were less willing to repeat ACBE than sigmoidoscopy (OR 1.85: 95% CI [1.13, 3.02]) or colonoscopy (OR 1.82: 95% CI [1.07, 3.09]). Initial and follow-up pain ratings by patients were highly correlated (Spearman correlation 0.81); however, correlation of pain assessments between staff and patients was poor (Spearman correlation 0.48). CONCLUSIONS: Sigmoidoscopy was more painful than other colonic imaging modalities. Although ACBE and colonoscopy caused similar pain, patients were less willing to repeat ACBE. In aggregate, the data suggest that patients perceive colonoscopy as the most acceptable colonic imaging procedure. Better methods are required to allow staff to adequately assess discomfort experienced by patients during these procedures.

The prevalence of CMA/CMPI in young children: the validity of parentally perceived reactions in a population-based study.

BACKGROUND: The present study aimed to estimate the prevalence of adverse reactions to milk, as population-based prevalence estimates based on objective diagnostic procedures are rare. METHODS: Children with parentally reported reactions to milk were selected for further examination from a population-based cohort of 2721 children. At the age of 2(1/2) years, they underwent a stepwise diagnostic procedure that included diet trials at home, skin prick tests, and open and double-blind, placebo-controlled food challenges. A sample of children with symptoms not attributed to milk was selected for assessment of unrecognized reactions. RESULTS: The estimated point prevalence of cow's milk allergy and cow's milk protein intolerance (CMA/CMPI) in children with parentally perceived reactions at the age of 2(1/2) years was estimated to be 1.1% (CI 0.8-1.6). However, this was an underestimate, as unrecognized reactions were detected. Most reactions were not IgE-mediated. The positive predictive value of a parentally perceived reaction depended on the number of times it had been reported and was good for reactions reported three times (at 12, 18, and 24 months of age). CONCLUSION: The present study confirms previous findings that parents overestimate milk as a cause of symptoms in their children; however, it also indicates that unrecognized reactions may be a problem as well.

The prevalence of allergy to egg: a population-based study in young children.

BACKGROUND: The aim of the present study was to estimate the prevalence of adverse reactions to egg, as population-based prevalence estimates based on objective diagnostic procedures are lacking. METHODS: The parents of 2721 children in a population-based birth cohort completed questionnaires on the occurrence of any reaction to food at 12, 18, and 24 months of age. Children with parentally reported reactions to eggs at the age of 2 years were selected for further examination. A stepwise diagnostic procedure was developed that included diet trials at home, skin prick tests, and open and double-blind, placebo-controlled food challenges. The mean age of the children at the time of the examination was 2.5 years (CI 2.5-2.6). A sample of children without perceived reactions to egg was also selected for assessment of unrecognized reactions. RESULTS: The estimated point prevalence of allergy to egg in children aged 2(1/2) years was 1.6% (CI 1.3-2.0%), with an upper estimate of the cumulative incidence by this age calculated roughly at 2.6% (CI 1.6-3.6). Almost all reactions were IgE mediated. In general, two-thirds of the parentally perceived reactions were verified. However, the positive predictive value of a parentally perceived reaction depended on the number of times it had been reported, and increased from 50% to 100%, for reactions reported one and three times, respectively. Unrecognized reactions were infrequent. CONCLUSION: This study confirms that allergy to egg is frequent in a child population.

Prospective comparison of catheter-based endoscopic sonography versus standard endoscopic sonography: evaluation of gastrointestinal-wall abnormalities and staging of gastrointestinal malignancies.

PURPOSE: Endoscopic sonography (EUS) is an important imaging modality for evaluating benign and malignant luminal gastrointestinal-tract abnormalities. The objectives of this study were to evaluate the feasibility of catheter-based EUS (C-EUS) during standard upper and lower endoscopy in patients with malignancies and other abnormalities of the gastrointestinal-tract lumen, to assess the image quality obtained with the 12.5-MHz catheter-based ultrasound transducer, and to prospectively compare the interpretations of C-EUS images with those of the standard EUS (S-EUS) images. METHODS: One hundred thirty-seven consecutive patients referred for EUS were evaluated with C-EUS followed by S-EUS. The patients were assigned to 1 of 2 groups: group A, patients with intramural masses or intestinal wall thickening, with biopsies negative for malignancy; and group B, patients with esophageal, gastric, duodenal, or rectal cancer referred for staging. The results of C-EUS and S-EUS were compared for each group. RESULTS: C-EUS was completed in 134 patients: 81 patients with 83 lesions in group A and 53 patients in group B. For group A, C-EUS image interpretation concurred with that of S-EUS in 74 (89%) of 83 lesions. For group B, C-EUS concurred with S-EUS for tumor depth (T) and nodal (N) classifications in 19 cases (36%) and 26 cases (49%), respectively. The depth of invasion was underestimated by C-EUS in all 34 cases in which the T classifications by C-EUS and S-EUS were discordant. In 1 of 6 patients with stenotic cancer that was nontraversable by S-EUS, C-EUS identified lymphadenopathy (incorrectly classified as N0 by S-EUS). CONCLUSIONS: C-EUS was easily performed, and the C-EUS images were comparable to the S-EUS images in assessing mucosal and intramural lesions. The limited depth of penetration of the catheter-based transducer resulted in understaging the extent of tumor invasion and underestimating the nodal spread.

Cinematic nuclear scintigraphy reliably directs surgical intervention for patients with gastrointestinal bleeding.

HYPOTHESIS: Cinematic technetium Tc 99m red blood cell ((99m)Tc-RBC) scans, in which real-time scanning is performed and analyzed, can accurately localize gastrointestinal bleeding and thus direct selective surgical intervention. DESIGN: Retrospective medical record review with historical controls. SETTING: Large, university-affiliated public hospital in urban setting. PATIENTS: Twenty-six patients presenting with upper and lower gastrointestinal hemorrhage who underwent cinematic (99m)Tc-RBC scan examinations between 1990 and 1997 and required surgical intervention to control the bleeding. INTERVENTIONS: All patients with gastrointestinal bleeding underwent open surgical procedures to provide cessation of bleeding and resection of appropriate abnormalities. MAIN OUTCOME MEASURES: Patient outcome was based on correlation between preoperative RBC scans and intraoperative findings, surgical pathology, and postoperative clinical course. RESULTS: Twenty-five (96%) of 26 scans were interpreted as positive for gastrointestinal bleeding. In 22 of these 25 scans, the site of bleeding was correctly identified for a sensitivity of 88%. One or more additional diagnostic tests were performed on 19 (73%) of 26 patients, and included angiography and flexible endoscopy. The most common operation performed to control bleeding was a hemicolectomy (14/26). Diverticulosis was the most prevalent diagnosis (46%). Two patients (8%) experienced rebleeding after operation. The overall mortality rate was 19% (5/26). CONCLUSIONS: Cinematic (99m)Tc-RBC scintigraphy is a sensitive, noninvasive alternative to mesenteric angiography for accurately localizing the site of gastrointestinal hemorrhages. As such, this technique can be reliably used to direct selective surgical intervention.

Nutrient intake among two-year-old children on cows' milk-restricted diets.

UNLABELLED: Approximately 2-3% of young children develop allergy or intolerance to cows' milk. The only available treatment is elimination of milk from the diet. However, as milk is an important source of nutrients in childhood, a milk-free diet may not adequately meet the child's nutritional needs. A dietary survey was conducted to assess the nutrient intake of children on cows' milk-restricted diets. A population-based sample of families with young children (31-37 mo) with adverse reaction to cows' milk and/or eggs was contacted, of which 75% agreed to complete a dietary intake assessment. Dietary intake was assessed using a 4-d weighed recording. The nutrient intake in a group of children on cows' milk protein-free (n = 16) and cows' milk reduced (n = 8) diets were compared to a group of cows' milk consumers (n = 10). There were significant differences in nutrient intake of children on milk-free diets and children consuming milk. Children on milk-free diets had significantly lower intake of energy, fat, protein, calcium, riboflavin and niacin. Use of milk substitutes improved the nutritional content of the cows' milk-free diets; however, the recommendations for riboflavin and calcium were still not met. CONCLUSION: The results reveal a risk for malnutrition in children on cows' milk-free diets, unless precautions are taken to replace the valuable nutrients from milk in the diet. Parents of children on milk-free diets need advice about food choices in order to reduce the risk of low intake of energy, fat and protein. Supplements with calcium, vitamin D and riboflavin are indicated.

Factors influencing T-cell turnover in HIV-1-seropositive patients.

HIV-1 disease is associated with pathological effects on T-cell production, destruction, and distribution. Using the deuterated (2H) glucose method for endogenous labeling, we have analyzed host factors that influence T-cell turnover in HIV-1-uninfected and -infected humans. In untreated HIV-1 disease, the average half life of circulating T cells was diminished without compensatory increases in cell production. Within 12 weeks of the initiation of highly active antiretroviral therapy (HAART), the absolute production rates of circulating T cells increased, and normal half-lives and production rates were restored by 12-36 months. Interpatient heterogeneity in the absolute degree of turnover correlated with the relative proportion of naive- and memory/effector-phenotype T cells in each of the CD4+ and CD8+ populations. The half-lives of naive-phenotype T cells ranged from 116-365 days (fractional replacement rates of 0.19-0.60% per day), whereas memory/effector-phenotype T cells persisted with half-lives from 22-79 days (fractional replacement rates of 0.87-3.14% per day). Naive-phenotype T cells were more abundant, and the half-life of total T cells was prolonged in individuals with abundant thymic tissue, as assessed by computed tomography. Such interpatient variation in T-cell kinetics may be reflective of differences in functional immune reconstitution after treatment for HIV-1 disease.

Multiple pulmonary nodules in AIDS: usefulness of CT in distinguishing among potential causes.

PURPOSE: To determine whether the computed tomographic (CT) appearances of multiple pulmonary nodules in patients with acquired immunodeficiency syndrome (AIDS) can help differentiate the potential infectious and neoplastic causes. MATERIALS AND METHODS: The thoracic CT scans obtained in 60 patients with AIDS and multiple pulmonary nodules were reviewed retrospectively by two thoracic radiologists who were blinded to clinical and pathologic data. The scans were evaluated for nodule size, distribution, and morphologic characteristics. CT findings were correlated with final diagnoses. RESULTS: Thirty-six (84%) of 43 patients with opportunistic infection had a predominance of nodules smaller than 1 cm in diameter, whereas 14 (82%) of 17 patients with a neoplasm had a predominance of nodules larger than 1 cm (P <.001). Of the 43 patients with opportunistic infection, 28 (65%) had a centrilobular distribution of nodules; only one (6%) of 17 patients with a neoplasm had this distribution (P <.001). Seven (88%) of eight patients with a peribronchovascular distribution had Kaposi sarcoma (P <.001). CONCLUSION: In patients with AIDS who have multiple pulmonary nodules at CT, nodule size and distribution are useful in the differentiation of potential causes. Nodules smaller than 1 cm, especially those with a centrilobular distribution, are typically infectious. Nodules larger than 1 cm are often neoplastic. A peribronchovascular distribution is suggestive of Kaposi sarcoma.

Prevalence of parentally perceived adverse reactions to food in young children.

A substantial number of parents perceive that their children have adverse reactions to food, but it is well documented that objective assessments agree with only one-quarter to one-half of parentally reported reactions. In order to prevent wrong diagnoses and curtail unnecessary or inadequate diets, primary health care providers need to deal with the parental perception of adverse reactions to food. A description of the prevalence and pattern of parentally perceived adverse reactions to food in children is needed to meet this challenge. The aim of the present study was to estimate the prevalence, incidence and cumulative incidences of parentally perceived adverse reactions to food in children younger than 2 years of age, and to study the duration of the reactions. A population-based cohort of 3623 children born in Norway was followed from birth until the age of two. At 6-month intervals, the parents completed questionnaires regarding the occurrence and type of any reaction to food. Information was available on the outcome measure at all age points for 77.4% of the families and these were used in the analyses; 3.8% of the cohort were entirely lost to follow-up. The cumulative incidence of adverse reactions to food was 35% by age two. Fruits, milk and vegetables accounted for nearly two-thirds of all reported reactions. Milk was the single food item most commonly incriminated, the cumulative incidence being 11.6%. The cumulative incidences of reported reactions to fruits and vegetables were 20.4% and 7.3%, respectively, with citrus fruits, strawberry and tomatoes as the most common food items in these groups. The cumulative incidences were less for food reactions associated with eggs (4.4%), fish (3%), nuts (2.1%) and cereals (1.4%). The duration of the reactions was short - approximately two-thirds of the reactions were not reported again 6 months later. However, the probability of remission depended on the food item concerned, the age at onset of reactions, and whether the reaction had been reported previously or not. Adverse reactions to food are reported by the parents of one-third of children in Norway before the age of two. The most striking feature of this study is the short duration of the food reactions, as approximately two-thirds of the reactions are not reported again 6 months later. Nevertheless, the high frequency of reactions attributable to milk is of concern. Milk is an important part of the Norwegian diet for children, and if removed from the diet its nutritional value is not easily replaced. Further studies are needed to assess the degree to which parents alter the diet of their children based upon perceived reactions to food.