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Biomedical subjects

D R Ownby

Publications and source records attributed to D R Ownby.

At least 19 recordsLinked to original sources

Occupational asthma in a beet sugar processing plant.

A patient with occupational asthma in the beet sugar processing industry is described. Symptomatology, skin testing, immunologic testing, and specific bronchoprovocation testing indicate exposure to moldy sugar beet pulp was the cause of the patient's occupational asthma. Cooperation between the treating physician and public health authorities is encouraged.

Adult

Evidence of cross-reactivity between olive, ash, privet, and Russian olive tree pollen allergens.

In a clinical investigation, 103 Michigan residents with symptoms suggestive of allergic rhinitis or asthma were skin tested with olive (Olea europaea) pollen extract. Nineteen had positive reactions. Since the olive tree is not native to nor grown in Michigan, this study was undertaken to determine whether the skin test reactivity was the result of cross-reactivity among tree pollen allergens. ELISAs were developed to measure olive, ash (Fraxinus americana), privet (Ligustrum vulgare), and Russian olive (Elaeagnus angustifolia) specific IgE antibodies. Inhibition studies were performed to determine whether pollen extracts from each of these tree species could inhibit IgE antibody binding to olive extracts. Eleven of the 19 skin test-positive patients were olive-ELISA positive, eight either were ELISA-positive to ash, seven to privet and ten to Russian olive. There were significant correlations between the ELISA results to olive and each of the other three pollens. The inhibition studies demonstrated that all three of the tree pollens were capable of inhibiting the binding of IgE to olive extract in a dose-response fashion. IgE-immunoblot studies demonstrated several proteins common to olive, ash, and privet. Twelve of the olive skin test-positive patients were contacted and 75% were exposed to one or more of the studied trees in their yards. Five patients had traveled to areas where olive trees are grown. We conclude that there is a high degree of cross-reactivity among allergens from native Michigan trees and from olive trees. This cross-reactivity is the most likely reason for skin test reactivity to olive pollen extract in Michigan.

Allergens

Maternal smoking does not influence cord serum IgE or IgD concentrations.

Increased cord blood IgE concentrations have been related to atopic risk in children, and a previous study reported increased cord blood IgE concentrations in smoking mothers. These associations suggest a relationship between maternal smoking during pregnancy and atopic risk. To evaluate this question, we prospectively studied parental smoking and cord blood IgE and IgD concentrations in a geographically defined group of women belonging to a health maintenance organization. Cord blood samples were obtained from 847 infants born to these women. Cotinine concentrations were measured in 114 cord blood samples to evaluate the veracity of the maternal smoking histories. Smoking during the prenatal period was reported by 144 mothers (17%) and 204 fathers (25%). Decreased birth weight and length were associated with maternal smoking (p less than 0.001 for both), confirming previous studies. Neither maternal nor paternal smoking was found to be associated with IgE level in univariate or multivariate analyses. Maternal and paternal smoking was associated with IgD (p = 0.03 and p = 0.06, respectively) in univariate analysis. In multiple regression analysis controlling for potentially confounding variables, the association between paternal, but not maternal, smoking and IgD was sustained (p = 0.05 and p greater than 0.20, respectively). Our data do not demonstrate that maternal or paternal smoking increases cord blood IgE.

Adult

Anaphylaxis associated with latex allergy during barium enema examinations.

During the interval from January 1989 to March 1990, signs and symptoms of anaphylaxis developed in six patients during barium enema examinations in our institution. In all six cases the symptoms of anaphylaxis began during the procedure, usually within 10 min of starting the examination. The principal manifestation of anaphylaxis was severe hypotension, usually accompanied by edema and urticaria. The symptoms were considered potentially life threatening in all patients, and one patient died despite prompt recognition of the anaphylactic nature of the reaction and resuscitative efforts. Serum samples were obtained within a few hours of the reaction in two patients and at autopsy in the fatal case: all three samples showed elevated concentrations of mast cell tryptase, demonstrating the systemic release of anaphylactic mediators. In vitro tests demonstrated the presence of immunoglobulin E antibodies specific for latex allergens in five of the six cases. Further in vitro inhibition tests confirmed the specificity of the antibodies for latex allergens and demonstrated that similar allergens were found in both raw latex, latex gloves, and catheter balloons. Only one patient was willing to undergo a skin test, and her skin test was positive for extracts of latex products. After considering multiple possibilities, we conclude that the reactions associated with barium enemas observed in these six patients are most probably the result of latex allergy.

Adult

Peak nasal inspiratory flow and Wright peak flow: a comparison of their reproducibility.

The measurement of peak nasal inspiratory flow (PNIF) is a rapid, convenient, and objective way to assess nasal patency. It is used much less commonly, however, than Wright Peak Flow (WPF), in part, because of concerns about its reproducibility. In order to compare the reproducibility of PNIF with WPF, we obtained multiple measurements of both flows in each of ten healthy, nonsmoking, trained subjects five times throughout the same day and daily throughout the same week. Mean PNIFs (L/min) were 140 immediately after arising, 170 at breakfast time, 183 at lunch time, 170 at dinner time, and 161 at bedtime. Corresponding mean WPFs were 528, 528, 535, 535 and 531 L/min. Peak nasal inspiratory flow coefficients of variation representing minute to minute, hour to hour, and day to day variation were 9.8, 13.5, and 9.7, respectively. Corresponding coefficients of variation with WPF, 2.4, 1.9, and 2.3, were significantly lower. Variability of PNIF and WPF did not increase with increased time spans, suggesting that variation in airway size is less important than variation in technique. Responses to intranasal oxymetazoline, as determined by changes in PNIF and changes in subjective assessments of nasal patency, were then evaluated in ten patients with nasal obstruction. These persons noted a mean subjective improvement of 68% (P = .0002) and demonstrated a mean objective improvement of 21% (P = .05). Posttreatment PNIFs of many individuals who reported substantial subjective improvement failed to exceed the expected variability of the test. This experience fails to demonstrate the utility of PNIF determinations for routine clinical use.

Adult

Risk of systemic reactions in patients taking beta-blocker drugs receiving allergen immunotherapy injections.

To learn whether patients taking beta-blocker (BB) drugs were at increased risk of having systemic reactions (SRs) from allergen immunotherapy, we prospectively studied 56,105 injection visits in 3178 patients during a 1-year interval. A total of 166 SRs occurred in 144 patients (4.5% of all patients) or 3.0 SRs occurred per 1000 injection visits. Sixty-eight patients were taking BB drugs throughout the year, and only one patient had an SR. By chance, 3.08 patients were expected to have had SRs. We conclude that BB drugs did not increase the frequency of SRs in the patients studied who were receiving immunotherapy (p greater than 0.95). Patients taking BB drugs may still be at increased risk, however, from more severe SRs or their SRs may be more refractory to therapy.

Adrenergic beta-Antagonists

Antibody responses in watermelon sensitivity.

Watermelon-specific IgE (WM-IgE) appears to mediate the oropharyngeal symptoms after watermelon ingestion. However, less than one fourth of watermelon-sensitive individuals (i.e., those with detectable WM-IgE) develop such symptoms after watermelon ingestion. In an attempt to separate symptomatic from asymptomatic persons, we measured watermelon-specific-IgE and IgG4 concentrations in the sera of 29 watermelon-sensitive patients, 6 of whom were symptomatic. Although the mean WM-IgE level of the symptomatic group exceeded that of the asymptomatic group (p = 0.04), individual WM-IgE values failed to distinguish symptomatic from asymptomatic persons. No differences in WM-IgG4 levels between the two groups could be found. Watermelon extract proteins were separated by isoelectric focusing and blotted to nitrocellulose membranes. The membranes were reacted with the individual sera of 14 watermelon-sensitive patients and then stained for IgE, IgG1, and IgG4 binding. Great variations in IgE, IgG1, and IgG4 binding patterns were found, but no subtype restrictions were discovered. Although the pattern of IgE-stained bands in the absence of corresponding IgG1-stained bands was seen more frequently in symptomatic individuals, immunoblot patterns failed to separate symptomatic from asymptomatic persons. We conclude that the pattern of IgE, IgG1, and IgG4 responses to separated watermelon allergens was not predictive of clinical symptoms in a group of watermelon-sensitive patients.

Adolescent

Passive exposure to cigarette smoke does not increase allergic sensitization in children.

The purpose of this study was to learn whether children passively exposed to parental cigarette smoke would be more frequently sensitized to common allergens or would have higher concentrations of allergen-specific IgE. To evaluate this question, we studied two groups of children aged 2 to 17 years. The first group consisted of 100 children selected from a general pediatric group practice. These children were being observed for well-child care, and the only selection criteria were the need for a venous blood sample for a reason unrelated to the study. The second group of 91 patients were consecutively referred, from the same pediatric group, for allergy evaluation because of respiratory tract symptoms. Parental smoking histories were obtained, and total serum IgE, IgD, and IgE specific for cat, dog, mite, ragweed, grass, and cockroach were measured by ELISA. Children of smoking mothers had significantly greater IgD concentrations (p = 0.03) and were more likely to be referred for allergy evaluation (p = 0.0001), but these children did not have increased concentrations of total or allergen-specific IgE. Exposed children were not more likely to be serologically sensitive to any of the allergens tested. We conclude that children passively exposed to cigarette smoke do not produce more IgE to common allergens nor are they more likely to produce IgE to any particular allergen.

Adolescent

Allergy testing: in vivo versus in vitro.

Table 4 briefly summarizes the relative advantages and disadvantages of skin tests versus in vitro tests for detecting allergen-specific IgE. The skin test remains unexcelled as a sensitive and cost efficient test for specific IgE. The high degree of skin test sensitivity is very important when a patient must be evaluated for potentially life-threatening allergies such as to penicillin or stinging insects. The results of both skin tests and in vitro assays depend very much on the quality of the allergen extracts used for the tests. Although the quality of extracts is improving, there is still little standardization. Both skin tests and in vitro assays are difficult to quality control. Practicing allergists rely on experience, and the correlation between patient histories and skin tests results for quality control of the results. Although this system suffices for common allergens, the results for uncommon allergens may be misleading. Quality control is also difficult for in vitro tests. Participation in quality control programs, such as that being offered by the College of American Pathologists, will increase and lead to better quality and standardization of in vitro test results. At the present time, properly performed skin tests are the best available method for detecting the presence of allergen specific IgE. They are rapid, sensitive, and inexpensive on a per test basis. In vitro tests are acceptable substitutes for skin tests in some circumstances. If the patient does not have normal skin, cannot discontinue interfering medications, or is so sensitive by history that anaphylaxis seems possible, in vitro tests are preferred. In vitro tests are better when it is necessary to test a difficult patient such as a combative, mentally retarded adult. In vitro tests also have been invaluable in many allergy research studies. Physicians must remember that positive tests for allergen-specific IgE do not diagnose allergy. They only indicate the presence of IgE molecules with a particular immunologic specificity. A decision whether the specific IgE molecules are responsible for clinically apparent disease must be made by a well-trained physician. The ultimate standard for the diagnosis of allergic disease remains the combination of: (1) positive double-blind challenge, (2) the presence of specific IgE, and (3) demonstration that the symptoms are the result of IgE-mediated inflammation.

Enzyme-Linked Immunosorbent Assay

Quantitative parameters of body composition and theophylline disposition.

The BA-101 Body Composition Analyzer provides values for percent fat, percent and total body water, percent lean body weight, and the lean to fat ratio. In 16 healthy adult male subjects, the volume of distribution of theophylline was found to be strongly correlated with the lean/fat ratio (r = .767) and to the percent fat (r = (-)0.79). Knowledge of body composition, however, did not allow for a more accurate prediction of a starter dose of theophylline.

Adipose Tissue

Watermelon and ragweed share allergens.

A biotin-avidin amplified ELISA was used to measure antigen-specific IgE for ragweed, representative members of the gourd family (watermelon, cantaloupe, honeydew melon, zucchini, and cucumber), and banana in the sera of 192 allergic patients, each with an IgE greater than or equal to 180 microns/ml. Sixty-three percent (120/192) of the sera contained antiragweed IgE, and of these patients, 28% to 50% contained IgE specific for any single gourd family member. In contrast, no greater than 11% of the sera positive for a given gourd or banana were negative for ragweed. Correlations between ragweed and gourd-specific IgE levels were significant (p less than 0.001), and correlation coefficients between any two gourds exceeded 0.79. In an ELISA system, the extracts of watermelon and ragweed inhibited each other in a dose-dependent manner; the resulting nonparallel inhibition curves indicate that some, but not all, of the allergens in the two extracts are cross-reactive. Isoelectric focusing of watermelon and ragweed extracts in narrow range gel (pH 4 to 6) followed by immunoblotting demonstrated six watermelon allergen bands with isoelectric points identical to those of ragweed allergens. Several remaining bands in the two extracts had differing isoelectric points, however. Six of 26 patients interviewed with watermelon-specific IgE reported developing oropharyngeal symptoms (itching and/or swelling of the lips, tongue, or throat) after ingesting at least one of the study foods, whereas only one of 25 patients interviewed without detectable watermelon-specific IgE reported similar symptoms (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Comparison of MAST with radioallergosorbent and skin tests for diagnosis of allergy in children.

The multiple allergosorbent test system (MAST) is a method for measuring total and allergen-specific IgE levels, using autoradiography and densitometry. The purpose of this study was to compare the results of MAST tests with those of radioallergosorbent (RAST) and skin tests as an adjunct to the diagnosis of allergy in children. Twenty children, aged 4 to 19 years, were studied. Total serum IgE level measured by the paper radioimmunosorbent test (PRIST) method ranged from 7 to 1,333 units/mL (geometric mean, 155 units/mL). Total serum IgE level by MAST significantly correlated with the PRIST IgE level. Quantities of allergen-specific IgE measured by MAST and RAST were also significantly correlated. When the diagnostic levels by MAST and RAST were compared with skin test reactions for ragweed, grass, house dust, and mite, MAST had a sensitivity of 59%, a specificity of 97%, and an efficiency of 72%, compared with 67%, 97%, and 78%, respectively, for the RAST analysis. We conclude that MAST and RAST are similar in their ability to measure allergen-specific IgE level, but that neither method is as sensitive as skin tests for detection of allergen-specific IgE.

Adolescent

Response to epinephrine in children receiving oral beta-agonists.

Physicians are sometimes concerned that the regular use of oral beta-agonists in the outpatient management of childhood asthma will result in decreased sensitivity or tachyphylaxis to these agents. While tachyphylaxis might not be clinically important during outpatient treatment, it could become significant during the emergency treatment of acute asthmatic attacks. We compared the increase in peak flow measurements before and 20 minutes after the injection of subcutaneous epinephrine hydrochloride in children with acute asthma and found no significant differences between those patients taking and those not taking oral beta-agonists.

Administration, Oral