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Biomedical subjects

V M Howie

Publications and source records attributed to V M Howie.

51 records · Page 3Linked to original sources
PubMed1973

Immunoglobulins of the middle ear fluid in acute otitis media: relationship to serum immunoglobulin concentrations and bacterial cultures.

Immunoglobulin concentrations were studied in 255 specimens of middle ear fluid (MEF) from 165 episodes of acute otitis media in children. There were significant amounts of all three major immunoglobulins (Ig) in MEF, the mean concentration of IgA being 39 mg/100 ml, of IgM 63 mg/100 ml, and of IgG 383 mg/100 ml. Secretory component was present in all 10 MEF specimens in which it was sought. In patients over 9 months of age, there was a decreased likelihood of isolating pathogenic bacteria from MEF if the patient had higher concentrations of IgA in MEF than in simultaneously obtained serum. IgA concentrations were greater in MEF than in serum in almost half the patients, and the mean MEF-serum ratio for IgA was 1.38. Thus, it would appear that in this disorder MEF represents primarily a secretory response to inflammation rather than a transudate.

Animals↗
PubMedDate not supplied

Efficacy of pneumococcal polysaccharide vaccine in preventing acute otitis media in infants in Huntsville, Alabama.

In a study of the efficacy of pneumococcal capsular polysaccharide vaccines in preventing otitis media due to Streptococcus pneumoniae, 179 infants were randomly assigned to receive either a "target" vaccine containing serotypes 1, 3, 6, 7, 14, 18, 19, and 23 (which account for most cases of pneumococcal otitis media) or a control vaccine containing serotypes 2, 4, 5, 8, 9, 12, and 25 (which account for few cases). Vaccine (0.5 ml) was administered subcutaneously; a dose contained 25 micrograms of each serotype. The incidence of otitis media due to "target" serotypes was determined in both groups. There were not significant differences between vaccines and controls in either the incidence or etiology of episodes of otitis media before immunization. During a two-year follow-up, no significant difference was observed regarding the incidence of episodes due to "target" serotypes in infants who were immunized after 12 months of age. However, of 66 control infants immunized before 12 months of age, 22 experienced 33 pneumococcal episodes due to a "target" serotype, whereas only 13 of 67 vaccines accounted for 22 such episodes. Among infants who had two or fewer episodes before immunization, four vaccines and 13 controls continued to have episodes of otitis media and became "otitis prone," i.e., six or more episodes (chi 2 = 4.84; P = 0.05). Low levels of serum antibody were not protective, and in one case a level of 609 ng of antibody nitrogen/ml of middle ear effusion was not protective. Thus, although the vaccine may be associated with a lower incidence of otitis media, the results of this study do not show a statistically significant efficacy of the vaccine.

Acute Disease↗
PubMedDate not supplied

Effects of early middle ear effusion on child intelligence at three, five, and seven years of age.

OBJECTIVE: This study tested the hypothesis that children with prolonged middle ear effusion (MEE) during the first 3 years of life are at risk for cognitive delays or deficits. METHOD: A prospective study enrolled 698 children from diverse backgrounds and controlled for eight demographic and environmental factors. Participants were recruited at birth and monitored for ear status frequently in the home; 379 children were assessed for cognition with the Stanford-Binet, 4th ed., at 3 years of age, 294 at 5 years, and 198 at 7 years. RESULTS: Using the SAS General Linear Models (GLM) procedure, we found a significant direct relation between duration of bilateral MEE and Stanford-Binet Composite and Nonverbal Reasoning/Visualization Factor scores at age 3, but not at age 5 or age 7. Statistical clustering analysis revealed four groups with different temporal patterns of MEE: Low MEE, Early MEE (peaking at 0-6 months), Later MEE (peaking at 6-12 months), and High MEE. GLM analyses revealed no direct effects, but several moderated effects, of MEE cluster on cognitive development at 3 years, but none at 5 or 7 years. In general, children in the Later MEE and High MEE groups appeared to be more adversely affected by bilateral MEE at 3 years, but effects were moderated in complex ways by socioeconomic status or home stimulation. Growth curve modeling across the three assessment periods showed no effects of total duration of MEE but did indicate that children in the Later MEE cluster had low scores at age 3 but caught up at ages 5 and 7. CONCLUSIONS: Prolonged MEE, especially between 6 and 12 months, may put children at risk for cognitive delays at 3 years, but the risk effect is not strong and effects are no longer detectable at 5 or 7 years.

Child↗
PubMedDate not supplied

Immunology and microbiology in acute otitis media.

Various immunological parameters were measured in serum, middle ear fluid (MEF), and lymphocytes from peripheral blood and MEF of infants with acute otitis media due to S. pneumoniae or H. influenzae. Approximately half of 131 patients had IgE specific antibody to the infecting bacterium as determined by the indirect fluorescent antibody (IFA) technique. Seventy-one percent of these IgE positive patients had IgE specific antibody in the MEF. Total IgE concentration was found to be from an average of 1.5 to 3.0 times higher in the MEF when compared to the simultaneously drawn serum. In addition, antibody to pneumococcal capsular polysaccharides and to pneumococcal C-carbohydrate was demonstrated in the MEF by radioimmunoassay. When MEF specific antibody was compared to serum antibody it appeared that antibody to C-carbohydrate was more concentrated in the MEF. That this antibody was of the IgE class was suggested by IFA but not conclusively proven. Evidence exists that conditions for enhanced IgE synthesis is concomitantly associated with a decrease in T-cell activity. T-cell function in MEF derived lymphocytes as determined by rosette formation and by phytohemagglutinin (PHA) stimulation was approximately one-tenth that of the peripheral blood lymphocytes. However, that T-cells may participate in the immune response to polysaccharides was suggested by the observation that polysaccharide stimulated peripheral blood lymphocytes from infants immunized with octavalent pneumococcal capsular vaccine underwent protein synthesis two to three times that of the PHA stimulated cells. The clinical significance of this finding as well as the nature of the cell responsible for the increased protein synthesis remains to be established. It is hypothesized that acute otitis media results from local synthesis of bacteria specific IgE antibody which is enhanced by a paucity of local T-cell activity.

Acute Disease↗