Biomedical subjects

Gerhard A Zielhuis

Publications and source records attributed to Gerhard A Zielhuis.

At least 19 recordsLinked to original sources

PubMed2006

Reproducibility of sonotubometry as Eustachian tube ventilatory function test in healthy children.

OBJECTIVES: To devise a simple and reliable diagnostic procedure to test Eustachian tube function routinely in an ENT outpatient setting. One method to measure ET ventilatory function is sonotubometry. The reproducibility of a recently updated sonotubometry set-up was tested in healthy children. METHODS: The test population comprised 61 school children aged from 6 to 8 years. Only otologically healthy children were included. Health state was established by means of a 12-item questionnaire. To test reproducibility, sonotubometric testing took place in two sessions of 10 acts of swallowing each. Spearman's coefficient was used to test the correlation between the two sets of measurements. All testing took place at a primary school in a nearby village. RESULTS: Opening of the ET was recorded in at least one of the two measurement sessions in 82% of the children. The first and second sessions were highly correlated, with a Spearman's coefficient of 0.89. CONCLUSIONS: In otologically healthy children, opening of the ET was recorded frequently using the updated sonotubometry set-up. Measurement results had high reproducibility. Therefore, the test forms a useful method to assess ET ventilatory function in otologically healthy children. The performance of this updated version needs to be established in children with otological diseases.

Acoustic Impedance Tests↗

PubMed2006

Possible role of the plasminogen activation system in human subfertility.

OBJECTIVE: To correlate components of the plasminogen activator (PA) system with fertility outcome parameters in participants in an IVF/intracytoplasmic sperm injection (ICSI) procedure. DESIGN: Case-control study. SETTING: Outpatient clinic for IVF/ICSI treatment at the Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. PATIENT(S): One hundred and fifty-six couples undergoing an IVF/ICSI procedure. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), and t-PA-PAI-1 complex concentrations in the ejaculate, spermatozoa, and follicular fluid (FF). RESULT(S): Concentrations of t-PA were higher in spermatozoa of the male factor subfertility group (geometrical mean, 77.1 pg/million spermatozoa; 25th-75th percentiles, 31.8-211.2), compared to fertile men (geometrical mean, 1.91; 25th-75th percentiles, 0.74-5.79) and idiopathic subfertile men (geometrical mean, 3.14; 25th-75th percentiles, 0.97-9.97). Furthermore, the concentration of t-PA in spermatozoa was significantly associated with pregnancy (odds ratio [OR], 0.995). Likewise, a trend was shown for higher t-PA concentrations in the FF of women with fallopian-tube pathology (geometrical mean, 18.5 pg t-PA/mg protein; 25th-75th percentiles, 11.4-25.7) or endometriosis (geometrical mean, 18.8; 25th-75th percentiles, 11.4-27.1), compared to fertile women (geometrical mean, 14.3; 25th-75th percentiles, 10.3-17.6) and idiopathic subfertile women (geometrical mean, 13.9; 25th-75th percentiles, 9.5-17.8). Also, t-PA in FF is associated with the proportion of cleaved embryos (regression coefficient, 0.16). The concentrations of u-PA, PAI-1, and t-PA-PAI-1 complex were comparable between diagnostic subgroups in both men and women. CONCLUSION(S): The t-PA concentrations in spermatozoa and FF tend to be higher in human subfertility, and seem to be associated with some fertility outcome parameters.

Adult↗

PubMed2006

Antimüllerian hormone predicts ovarian responsiveness, but not embryo quality or pregnancy, after in vitro fertilization or intracyoplasmic sperm injection.

Antimüllerian hormone (AMH) and other markers of ovarian reserve were assessed to determine their predictive value with respect to treatment outcome. In a multivariate regression analysis, AMH was found to be predictive of the number of oocytes and the number of embryos, but not of embryo quality or the chance of a pregnancy, after IVF/ICSI.

Adult↗

PubMed2006

Prediction of asthma in young adults using childhood characteristics: Development of a prediction rule.

OBJECTIVE: To develop an easily applicable prediction rule for asthma in young adulthood using childhood characteristics. METHODS: A total of 1,055 out of 1,328 members of a Dutch birth cohort were followed from 2 to 21 years of age. Univariate and multivariate logistic regression analyses were used to evaluate the predictive value of childhood characteristics on asthma at 21 years of age. A prognostic function was developed, and the area under the receiving operating characteristic (ROC) curve was used to estimate the predictive ability of the prognostic models. RESULTS: Of the 693 responding subjects, 86 (12%) were diagnosed with asthma. Independent prognostic factors at ages 2 and 4 years were female gender (odds ratios (OR) 1.9 and 2.1; 95% confidence intervals (CI) 1.2-3.2 and 1.3-2.5), smoking mother (OR 1.6 and 1.6; CI 1.0-2.7 and 1.0-2.6), lower respiratory tract illness (OR 1.9 and 2.4; CI 1.0-3.6 and 1.4-4.0), and atopic parents (OR 2.1 and 1.9; CI 1.3-3.4 and 1.2-3.1). The predictive power of both models was poor; area under ROC curve was 0.66 and 0.68, respectively. CONCLUSION: Asthma in young adulthood could not be predicted satisfactorily based on childhood characteristics. Nevertheless, we propose that this method is further tested as a tool to predict development of asthma.

Adolescent↗

PubMed2006

Pesticide exposure: the hormonal function of the female reproductive system disrupted?

Some pesticides may interfere with the female hormonal function, which may lead to negative effects on the reproductive system through disruption of the hormonal balance necessary for proper functioning. Previous studies primarily focused on interference with the estrogen and/or androgen receptor, but the hormonal function may be disrupted in many more ways through pesticide exposure. The aim of this review is to give an overview of the various ways in which pesticides may disrupt the hormonal function of the female reproductive system and in particular the ovarian cycle. Disruption can occur in all stages of hormonal regulation: 1. hormone synthesis; 2. hormone release and storage; 3. hormone transport and clearance; 4. hormone receptor recognition and binding; 5. hormone postreceptor activation; 6. the thyroid function; and 7. the central nervous system. These mechanisms are described for effects of pesticide exposure in vitro and on experimental animals in vivo. For the latter, potential effects of endocrine disrupting pesticides on the female reproductive system, i.e. modulation of hormone concentrations, ovarian cycle irregularities, and impaired fertility, are also reviewed. In epidemiological studies, exposure to pesticides has been associated with menstrual cycle disturbances, reduced fertility, prolonged time-to-pregnancy, spontaneous abortion, stillbirths, and developmental defects, which may or may not be due to disruption of the female hormonal function. Because pesticides comprise a large number of distinct substances with dissimilar structures and diverse toxicity, it is most likely that several of the above-mentioned mechanisms are involved in the pathophysiological pathways explaining the role of pesticide exposure in ovarian cycle disturbances, ultimately leading to fertility problems and other reproductive effects. In future research, information on the ways in which pesticides may disrupt the hormonal function as described in this review, can be used to generate specific hypotheses for studies on the effects of pesticides on the ovarian cycle, both in toxicological and epidemiological settings.

Animals↗

PubMed2006

Persistence of upper respiratory tract infections in a cohort followed from childhood to adulthood.

OBJECTIVE: To assess (1) prevalences of recurrent URTIs (rURTIs) and relapsing/persistent rURTIs and associated medical consumption between 0 and 21 years of age and (2) whether rURTIs experienced in early life predispose to upper airway disease later in life. METHODS: A cohort of all children born in Nijmegen, The Netherlands, between September 1982 and September 1983, was assessed repeatedly from 2 to 21 years of age with questionnaires regarding infections of the upper respiratory tract (URTIs), use of antibiotics, ENT operations and known risk factors for URTIs. RESULTS: One hundred and sixty-one of the 693 cohort member (23%) suffered from relapsing rURTIs between 0 and 21 years of age, whereas only 7 (1%) suffered from persistent rURTIs throughout this period. Two hundred and six (30%) had used antibiotics more than once; and 220 (32%) had undergone at least one ENT operation. Of the 166 participants with rURTI between 8 and 21 years, 140 (84%) had had rURTI before. CONCLUSIONS: rURTIs are highly prevalent throughout early life and associated medical consumption is substantial. The challenge therefore is to develop therapeutic/preventive strategies that will prevent rURTIs in the first years of life.

Adolescent↗

PubMed2006

Predictors of chronic suppurative otitis media in children.

OBJECTIVE: To determine which factors predict development of chronic suppurative otitis media (CSOM) in children. DESIGN: Case-control study, with univariate and multivariate logistic regression analysis applied to determine which factors independently predict CSOM. SUBJECTS: Prognostic factors for CSOM were identified in (1) 100 children with CSOM and 161 controls aged 1 to 12 years and (2) 83 children who developed CSOM in the presence of a tympanostomy tube and 136 children with tympanostomy tubes who did not develop CSOM. RESULTS: Independent predictors for CSOM were previous tympanostomy tube insertion (odds ratio [OR], 121.4 [95% confidence interval {CI}, 38.9-379.3]); having had more than 3 upper respiratory tract infections in the past 6 months (OR, 12.2 [95% CI, 3.5-42.3]); having parents with a low education level (OR, 14.1 [95% CI, 2.9-68.6]); and having older siblings (OR, 4.4 [95% CI, 1.6-12.6]). Independent predictors for CSOM after tympanostomy tube insertion were having experienced more than 3 episodes of otitis media in the past year (OR, 4.9 [95% CI, 2.2-11.0]; attending day care (OR, 3.6 [95% CI, 1.7-7.8]); and having older siblings (OR, 2.6 [95% CI, 1.2-5.5]). CONCLUSIONS: Treatment with tympanostomy tubes is the most important prognostic factor for CSOM in children. In children who are being treated with tympanostomy tubes for persistent middle ear effusion, the most important prognostic factor for CSOM is a history of recurrent episodes of acute otitis media. This information should be taken into consideration and discussed with parents when considering insertion of tympanostomy tubes in children.

Case-Control Studies↗

PubMed2006

Periconceptional health and lifestyle factors of both parents affect the risk of live-born children with orofacial clefts.

BACKGROUND: Nonsyndromic cleft lip with or without cleft palate (CL/P) or cleft palate only (CPO) are orofacial clefts and have a multifactorial etiology. The identification of amendable parental risk factors may contribute to a reduced occurrence of these malformations in the future. METHODS: Standardized demographic and periconceptional exposure data from 284 parents of a child with CL/P, 66 parents of a child with a CPO and 222 parents of a child without congenital malformations were collected at approximately 24 months after the periconceptional period of the index child. Univariate and multivariate logistic regression analyses were used to estimate relative risks by odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Univariate results suggest that low parental education, periconceptional maternal medication use and illnesses, paternal smoking, and first-trimester maternal common cold increased CL/P risk. Pregnancy planning and periconceptional folic acid supplementation, however, reduced CL/P risk by approximately 50% (OR, 0.5; 95% CI, 0.3-0.8) and 40% (OR, 0.6; 95% CI, 0.4-0.9), respectively. Mostly comparable results were obtained for CPO. Being a boy (OR, 2.0; 95% CI, 1.4-3.0), folic acid supplementation (OR, 0.6; 95% CI, 0.4-0.9), and low paternal education (OR, 1.6; 95% CI, 1.0-2.3) mainly determined CL/P in the multivariate analyses, compared to low paternal (OR, 4.5; 95% CI, 2.1-9.4) and maternal medication use (OR, 2.0; 95% CI, 1.0-4.0) for CPO. CONCLUSIONS: Preconceptional counseling for orofacial cleft risk assessment should pay attention to maternal medication use, periconceptional folic acid supplementation, and exposures of the father. These determinants can be amended, thereby modifying orofacial cleft risk.

Adult↗

PubMed2006

Effect of combined pneumococcal conjugate and polysaccharide vaccination on recurrent otitis media with effusion.

BACKGROUND: Otitis media with effusion (OME) is very common during childhood. Because Streptococcus pneumoniae is one of the most common bacterial pathogens involved in OME, pneumococcal vaccines may have a role in the prevention of recurrent OME. OBJECTIVE: We sought to assess the effect of combined pneumococcal conjugate and polysaccharide vaccinations on the recurrence of OME. METHODS: A randomized, controlled trial was performed with 161 children, 2 to 8 years of age, with documented persistent bilateral OME. All subjects were treated with tympanostomy tubes (TTs). One half of the subjects were assigned randomly to additional vaccination with a 7-valent pneumococcal conjugate vaccine 3 to 4 weeks before and a 23-valent pneumococcal polysaccharide vaccine 3 months after tube insertion. Blood samples were drawn at the first vaccination, at the time of TT placement, and 1 and 3 months after the second vaccination. Levels of IgA and IgG serum antibody against the 7-valent pneumococcal conjugate vaccine serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F were measured with enzyme-linked immunosorbent assays. All children were monitored for recurrence of OME for 6 months after spontaneous extrusion of the TTs. RESULTS: The overall recurrence rate of bilateral OME was 50%. Pneumococcal vaccinations induced significant 4.6- to 24.4-fold increases in the geometric means of all conjugate vaccine serotype antibody titers but did not affect recurrence of OME. CONCLUSIONS: Combined pneumococcal conjugate and polysaccharide vaccination does not prevent recurrence of OME among children 2 to 8 years of age previously known to have persistent OME. Therefore, pneumococcal vaccines are not indicated for the treatment of children suffering from recurrent OME.

Child↗

PubMed2006

Time to pregnancy among female greenhouse workers.

OBJECTIVES: Female greenhouse workers, who constitute a major occupational group exposed to pesticides at childbearing age, were studied to measure the effects of pesticide exposure on time to pregnancy. METHODS: Data were collected through postal questionnaires with detailed questions on time to pregnancy, lifestyle factors (eg, smoking habits, coffee and alcohol consumption), and worktasks (eg, application of pesticides, re-entry activities, and workhours) of the respondents and their partners in a 6-month period prior to conception of the most recent pregnancy. The relation between time to pregnancy and exposure to pesticides among 398 female greenhouse workers and 524 referents was studied in a Cox's proportional hazards model. RESULTS: The crude fecundability ratio for female greenhouse workers versus the reference group was 1.18 [95% confidence interval (95% CI) 1.03-1.35], but correction for confounding changed the fecundability ratio to 1.11 (95% CI 0.96-1.29). An evaluation of specific biases for time-to-pregnancy studies showed that these results were biased by the reproductively unhealthy worker effect. Restricting the analyses to full-time workers or first pregnancies only resulted in an adjusted fecundability ratio of 0.89 (95% CI 0.67-1.19) and 0.90 (95% CI 0.62-1.32), respectively. Among the primigravidous greenhouse workers, an association was observed between prolonged time to pregnancy and gathering flowers (fecundability ratio 0.46, 95% CI 0.18-1.19). CONCLUSIONS: This study may offer some evidence for the hypothesis of adverse effects of pesticide exposure on time to pregnancy, but more research is needed to elucidate these effects.

Adult↗

PubMed2005

An investigation of clinical studies suggests those with multiple objectives should have at least 90% power for each endpoint.

BACKGROUND AND OBJECTIVES: Many clinical studies have more than one objective, either formally or informally, but this is not usually taken into account in the determination of the sample size. We investigated the overall power of a study, that is, the probability that all the objectives will be met. METHODS: We calculated the overall power in the case that the study has two primary outcome variables and in the case that one outcome variable is evaluated on two subsets, in particular, the Per Protocol group and the Intention to Treat group. RESULTS: A power of 80% for each of the two end points leads to poor power for the end points combined. However, a power of 90% preserves better the overall power. The power of the Per Protocol analysis can be higher or lower than the power of the Intention to Treat analysis. CONCLUSION: Power should be calculated for all end points combined, and it should be at least 90% for each primary end point. If the sample size for the intention-to-treat analysis is determined by adding a percentage of "nonevaluable subjects" to the sample size required for the per protocol analysis, then this may lead to an underpowered study.

Analysis of Variance↗

PubMed2005

Sequential balancing: a simple method for treatment allocation in clinical trials.

Although minimisation methods have frequently been advocated for treatment allocation in clinical trials, they are not widely used. As this may partly be due to the complexity of the methods, we devised a new and simple minimisation method to balance for prognostic factors, called sequential balancing. Each factor is dealt with sequentially and when a new subject enters the trial, he or she is allocated the treatment that leads to improved balance of the first factor over the treatments. If the balance of the first factor was already satisfactory, then the treatment is allocated that leads to improved balance of the second factor and so on. The algorithm requires no calculations. We simulated a realistic trial and compared the performance of this method to the performance of alternative allocation strategies: the variance minimisation method, simple randomisation and stratification. The sequential balancing method led to better balance than randomisation and stratification. In the case of four factors or less, the performance of the sequential balancing method and the variance minimisation method were comparable and the sequence of the factors was not very relevant. When more factors were introduced, the balance of the sequential method remained comparable with the balance achieved with the variance minimisation method for the first four factors, but it started to decrease from the fifth factor onwards. We conclude that the ease and simplicity of the new method make it an attractive option when balance is required for four factors or less. If there are more than four factors, the sequential balancing method may still be an acceptable option, but the advantage of simplicity has to be weighed against the loss of performance compared to other minimisation methods.

Age Factors↗

PubMed2005

Birth characteristics and recurrent otitis media with effusion in young children.

OBJECTIVE: To study the association between birth characteristics and the recurrence of otitis media with effusion (OME). METHODS: Prospective cohort study on 136 children aged 2-7 years, who received tympanostomy tubes for bilateral otitis media with effusion. Checkups were planned 1 week after tube insertion and once every 3 months thereafter. An otologist examined the ear status to assess tube extrusion and otitis media with effusion recurrence. Outcome measure was the recurrence of otitis media with effusion within 6 months after documentation of spontaneous tube extrusion. Birth characteristics were investigated in relation with the recurrence of otitis media with effusion in 90 children with known clinical outcome. RESULTS: No statistically significant associations were found between various birth characteristics and the recurrence of otitis media with effusion. Multivariate analyses showed positive but fairly weak associations between recurrence of otitis media with effusion and low birth weight (<2500 g) and/or low gestational age (<37 weeks) and/or a history of incubator care (odds ratio (OR) 1.95, 95% confidence interval (CI): 0.21-18.2), male sex (OR 1.85, 95% CI: 0.56-6.13) and maternal medication use during pregnancy (OR 4.80, 95% CI: 0.57-40.72). A remarkable finding was the asymmetrical distribution of certain birth characteristics within the group of children with recurrence of otitis media with effusion: children with unilateral recurrence had a relatively lower gestational age, lower birth weight, lower 'birth length to birth weight' ratio than the children with bilateral recurrence. CONCLUSION: These findings suggest that determination of birth characteristics cannot help us in the treatment strategy for recurrent otitis media with effusion in childhood.

Birth Weight↗

PubMed2005

Eustachian tube function before recurrence of otitis media with effusion.

OBJECTIVE: To study the role of eustachian tube function in the development of recurrent otitis media with effusion (OME) in children treated with tympanostomy tubes for OME. DESIGN: Prospective cohort study. SETTING: Three academic and general hospitals. PATIENTS: Children aged 2 to 7 years with a first clinical episode of OME that persisted for at least 3 months; 136 (81%) of 168 eligible children participated. All children received tympanostomy tubes for bilateral OME at study entry. MAIN OUTCOME MEASURE: Recurrence of OME within 6 months of tube extrusion. RESULTS: No statistically significant differences were present in eustachian tube function test results between ears that developed recurrent OME and those that did not. The difference in passive ventilatory function between ears with and without OME recurrence was 10 daPa (95% confidence interval, -24 to 43 daPa) for opening pressure and -3 daPa (95% confidence interval, -18 to 11 daPa) for closing pressure. The overall difference in the proportion of ears with and without OME recurrence that could not equilibrate positive and negative applied pressures was 12% (95% confidence interval, -2% to 26%). The proportions of ears with and without OME recurrence that induced negative pressure in the middle ear by forcefully sniffing were 22% and 31%, respectively (P = .75). CONCLUSION: Measurement of ventilatory and protective eustachian tube function using the forced response test, the pressure equilibration test, and the sniff test has no value in predicting whether children have an increased risk of OME recurrence.

Child, Preschool↗

PubMed2005

Immune status and eustachian tube function in recurrence of otitis media with effusion.

OBJECTIVE: To study the combined role of immune status and eustachian tube function in the development of recurrent bilateral otitis media with effusion (OME). DESIGN: Prospective cohort study. SETTING: Three academic and general hospitals. PATIENTS: Children aged 2 to 7 years with a first clinical episode of bilateral OME that persisted for at least 3 months; 136 (81%) of 168 eligible children participated. All children received bilateral tympanostomy tubes at study entry. MAIN OUTCOME MEASURE: Recurrence of bilateral OME within 6 months after tube extrusion. RESULTS: Univariate analyses of various immunologic factors (IgA, IgG1, IgG2, IgG3, IgG4, mannose-binding lectin, and the FcgammaRIIa-H/R131 genotype) and eustachian tube function (forced response test) did not show any significant associations with bilateral OME recurrence. Multivariate analyses showed that children with closing pressures higher than the 75th percentile and IgA or IgG2 levels below the 50th percentile of the cohort were more likely to develop recurrent OME than children with closing pressures higher than the 75th percentile and IgA or IgG2 levels above the 50th percentile. The corresponding risk ratios were 6.3 (95% confidence interval [CI], 1.0-40.1) for IgA level and 3.0 (95% CI, 1.1-8.2) for IgG2 level. The multivariate analyses also revealed that increasing serum levels of functional mannose-binding lectin were associated with decreasing probabilities of developing recurrent OME (odds ratio, 0.7; 95% CI, 0.6-1.0). CONCLUSION: Recurrence of bilateral OME after tympanostomy tube placement is more likely in children with a combination of low IgA or low IgG2 levels with poor eustachian tube function and decreased levels of mannose-binding lectin.

Antigens, CD↗

PubMed2005

The effect of otitis media in childhood on the development of middle ear admittance on reaching adulthood.

OBJECTIVES: To determine the long-term change in static admittance values of subjects with a positive or negative history of otitis media (OM) and ventilation tube (VT) insertion; and to investigate the association between static admittance values and tympanic membrane abnormalities. DESIGN: Prospective follow-up study. SUBJECTS: A total of 358 subjects with or without a history of OM (OM+ or OM-) and VT insertion (VT+ or VT-) derived from a birth cohort that had been observed from preschool to adulthood. MAIN OUTCOME MEASURES: Otomicroscopic and tympanometric data obtained at subject ages 8 and 18 years. RESULTS: Static admittance values generally increased with age. At age 8 years, static admittance values were highest in OM+VT+ ears and lowest in OM- ears. At age 18 years, the difference between OM+VT+ and OM+VT- ears was larger, while the difference in static admittance values between OM+VT- and OM- ears had disappeared. In the group of VT+ subjects, the proportion of extreme static admittance values increased from 16% to 35% between ages 8 and 18 years. Correlation coefficients of individual static admittance values at 8 and 18 years were high in all groups and ranged from 0.61 to 0.85. We could not demonstrate an intermediate role of tympanic membrane abnormalities in the relation between VTs and static admittance at young adult age, except for atrophy. CONCLUSIONS: The static admittance value at age 8 years was a strong predictor for the value at age 18 years. A VT+ status was associated with a larger increase in static admittance than can be explained on the basis of age alone.

Acoustic Impedance Tests↗

PubMed2005

Bayes' theorem: a negative example of a RCT on grommets in children with glue ear.

Bayesian inference presupposes that practitioners' belief in the effectiveness of medical intervention is the product of prior belief and recent evidence from studies. Although increasingly used, up to now the posterior belief calculated according to the theorem has not been compared with an empirically measured posterior belief. We conducted a RCT, which was preceded by elicitation of prior beliefs among ENT-surgeons, and which was followed by elicitation of posterior beliefs among ENT-surgeons, 1 year after completion of the trial. We compared the posterior beliefs of ENT-surgeons about the effect of grommets in children with glue ears, as predicted by Bayes' theorem with actual measured posterior beliefs. The distribution of the measured posterior beliefs was not in line with the calculated posterior, but almost identical to the distribution of the measured prior beliefs. The results showed that our trial had little or no impact on the beliefs of the ENT-surgeons, i.e. they did not adjust their belief to the extent that was expected according to Bayes' theorem.

Bayes Theorem↗

PubMed2005

Immunological status in the aetiology of recurrent otitis media with effusion: serum immunoglobulin levels, functional mannose-binding lectin and Fc receptor polymorphisms for IgG.

The objective was to study the role of serum immunoglobulin levels, mannose-binding lectin (MBL), and Fc gamma receptor (FcgammaR) polymorphisms on the development of recurrent otitis media with effusion (OME). Children aged between two and seven years with persisting OME received bilateral tympanostomy tubes and immunological parameters were investigated in relation with OME recurrence within six months after tube extrusion. No statistically significant differences in serum immunoglobulin levels were present between children with and without OME recurrence. In children with bilateral recurrence (n = 56), median levels of MBL were 1.39 mg/L compared to 2.48 mg/L in children with OME recurrence (n = 17) (p = 0.29). In addition, 34% of the children with bilateral recurrence were homozygous for the genotype FcgammaRIIa-R/R131, whereas less than 20% of the children with unilateral recurrence or those without recurrence were homozygous for this Fcgamma receptor (p = 0.26). Serum mannose-binding lectin and FcgammaRIIa-R/R131 polymorphism may play a role in the aetio-pathogenesis of recurrent OME.

Child↗