Olfactory Function In Children Research Articles

The Study of the Sense of Smell in Children: Development Prospects

Background. Despite the fact that the study of the olfactory system is still difficult, the detection of dysosmia is promising for the diagnosis of a number of diseases. As a screening method, tests for the identification of various odors can be used. However, similar tests are developed and used for adults. In pediatrics, the use of such methods causes difficulty due to the cognitive and linguistic functions of the child, which are in the stage of development. Aim — to study olfactory function in children using an identification test. Methods. A diagnostic prospective study of 30 healthy children with no complaints of decreased olfactory function, living in the middle zone of the Russian Federation, mainly in the Moscow Metropolitan area, aged 11 to 14 y.o. was held. All children underwent a study of olfactory function using the University of Pennsylvania Smell Identification Test (UPSIT). To control all children, olfactometry was performed using a patented method for assessing the thresholds of olfaction in children, based on the use of various concentrations of aqueous solutions of valerian tincture, ammonia and acetic acid. Results. In the study of sense of smell with the help of an UPSIT test, hyposmia was detected in 30% of children, which was not confirmed later with the help of a threshold test. At the same time, when presenting some odorants, most of the answers were incorrect. Conclusions. The use of olfactory tests developed for adults in children does not reflect the real state of the olfactory system. It is required to create kits for the study of the olfactory function specifically for the children’s category of patients.

A multi-environmental source approach to explore associations between metals exposure and olfactory identification among school-age children residing in northern Italy.

Metal exposures can adversely impact olfactory function. Few studies have examined this association in children. Further, metal exposure occurs as a mixture, yet previous studies of metal-associated olfactory dysfunction only examined individual metals. Preventing olfactory dysfunctions can improve quality of life and prevent neurodegenerative diseases with long-term health implications. We aimed to test the association between exposure to a mixture of 12 metals measured in environmental sources and olfactory function among children and adolescents residing in the industrialized province of Brescia, Italy. We enrolled 130 children between 6 and 13 years old (51.5% females) and used the "Sniffin' Sticks" test to measure olfactory performance in identifying smells. We used a portable X-ray fluorescence instrument to determine concentrations of metals (arsenic (As), calcium, cadmium (Cd), chromium, copper, iron, manganese, lead (Pb), antimony, titanium, vanadium and zinc) in outdoor and indoor deposited dust and soil samples collected from participants' households. We used an extension of weighted quantile sum (WQS) regression to test the association between exposure to metal mixtures in multiple environmental media and olfactory function adjusting for age, sex, socio-economic status, intelligence quotient and parents' smoking status. A higher multi-source mixture was significantly associated with a reduced Sniffin' Sticks identification score (β = -0.228; 95% CI -0.433, -0.020). Indoor dust concentrations of Pb, Cd and As provided the strongest contributions to this association (13.8%, 13.3% and 10.1%, respectively). The metal mixture in indoor dust contributed more (for 8 metals out of 12) to the association between metals and olfactory function compared to soil or outdoor dust. Among a mixture of 12 metals measured in three different environmental sources (soil, outdoor and indoor dust), we identified Pb, Cd and As measured in indoor dust as the main contributors to reduced olfactory function in children and adolescents residing in an industrialized area. Exposure to indoor pollution can be effectively reduced through individual and public health interventions allowing to prevent the deterioration of olfactory functions. Moreover, the identification of the factors that can deteriorate olfactory functions can be a helpful instrument to improve quality of life and prevent neurodegenerative diseases as long-term health implications.

Olfactory function after mild traumatic brain injury in children-a longitudinal case control study.

The prevalence of posttraumatic olfactory dysfunction in children after mild traumatic brain injury ranges from 3 to 58%, with potential factors influencing this variation, including traumatic brain injury severity and assessment methods. This prospective longitudinal study examines the association between mild traumatic brain injury and olfactory dysfunction in children. Seventy-five pediatric patients with mild traumatic brain injury and an age-matched healthy control group were enrolled. Olfactory function was assessed using the Sniffin' Sticks battery, which focuses on olfactory threshold and odor identification. The study found that children with mild traumatic brain injury had impaired olfactory function compared with healthy controls, particularly in olfactory threshold scores. The prevalence of olfactory dysfunction in the patient group was 33% and persisted for 1yr. No significant association was found between traumatic brain injury symptoms (e.g. amnesia, loss of consciousness) and olfactory dysfunction. The study highlights the importance of assessing olfactory function in children after mild traumatic brain injury, given its potential impact on daily life. Although most olfactory dysfunction appears transient, long-term follow-up is essential to fully understand the recovery process. The findings add valuable insights to the limited literature on this topic and urge the inclusion of olfactory assessments in the management of pediatric mild traumatic brain injury.

The Effect of Methylphenidate Treatment on Olfactory Function in Children and Adolescents With ADHD

Objective: This study aimed to research whether there is an olfactory disorder in ADHD, and if so, what is the effect of methylphenidate on this condition. Method: This is a cross-sectional study aiming to evaluate olfactory threshold, identification, discrimination and threshold, discrimination, and identification (TDI) scores in 109 children and adolescents, 33 of whom have ADHD without medication, 29 with ADHD with medication and 47 control groups. Result: In the post hoc tests, the mean odor discrimination test, the mean odor identification test, and the mean TDI scores of the unmedicated ADHD group were significantly lower than those of the other two groups, and that the mean odor threshold test scores of the medicated ADHD group were significantly lower than those of the control and unmedicated groups. Conclusion: Olfactory function could be a useful tool to monitor treatment effects and may be a promising candidate as a biomarker in ADHD.

Olfactory training reduces pain sensitivity in children and adolescents with primary headaches.

Headache prevalence among children and adolescents has increased over the last few years. Evidence-based treatment options for pediatric headaches remain limited. Research suggests a positive influence of odors on pain and mood. We investigated the effect of repeated exposure to odors on pain perception, headache-related disability, and olfactory function in children and adolescents with primary headaches. Eighty patients with migraine or tension-type headache (mean 13.1 ± 3.29 years) participated, of whom 40 underwent daily olfactory training with individually selected pleasant odors for 3 months and 40 received state-of-the-art outpatient therapy as a control group. At baseline and after a 3-month follow-up, olfactory function [odor threshold; odor discrimination; odor identification; comprehensive Threshold, Discrimination, Identification (TDI) score], mechanical detection and pain threshold (quantitative sensory testing), electrical pain threshold, patient-reported outcomes on headache-related disability [Pediatric Migraine Disability Assessment (PedMIDAS)], pain disability [Pediatric Pain Disability Index (P-PDI)], and headache frequency were assessed. Training with odors significantly increased the electrical pain threshold compared to the control group (U = 470.000; z = -3.177; p = 0.001). Additionally, olfactory training significantly increased the olfactory function (TDI score [t(39) = -2.851; p = 0.007], in particular, olfactory threshold, compared to controls (U = 530.500; z = -2.647; p = 0.008). Headache frequency, PedMIDAS, and P-PDI decreased significantly in both groups without a group difference. Exposure to odors has a positive effect on olfactory function and pain threshold in children and adolescents with primary headaches. Increased electrical pain thresholds might reduce sensitization for pain in patients with frequent headaches. The additional favorable effect on headache disability without relevant side effects underlines the potential of olfactory training as valuable nonpharmacological therapy in pediatric headaches.

Smell Status in Children Infected with SARS-CoV-2.

Objectives/HypothesisThis study aimed to evaluate the olfactory status in children with laboratory confirmed SARS‐CoV‐2 using subjective and psychophysical methods.Study DesignProspective clinical cross‐sectional study.MethodsThis is a prospective clinical cross‐sectional study of 79 children with COVID‐19. The 21st item of SNOT‐22 questionnaire and odor identification test were used for smell assessment. Children were examined twice during the hospitalization, and a telephone survey was conducted 60 days after hospital discharge.ResultsImmediately after confirmation of COVID‐19, smell impairment was detected in 86.1% of children by means of the Identification test and in 68.4% of children by means of the survey (P = .010). After 5 days survey revealed a statistically significant decrease in the number of patients with hyposmia (41 out of 79, 51.9%). On the first visit, the mean Identification test score corresponded to “hyposmia” (9.5 ± 2.7), while on the second visit, the average value was 13.1 ± 1.9, which corresponded to “normosmia.” According to the telephone survey, recovery of the olfactory function occurred within 10 days in 37 of 52 patients (71.2%), 11 to 29 days ‐ in 12 children (23.1%), and later than 30 days ‐ in three cases (5.7%).ConclusionsIn the pediatric population, olfactory dysfunction is an early and common symptom of COVID‐19. There is a trend to quick recovery of olfactory function in children with COVID‐19. The overwhelming majority of patients (94.3%) had no subjective olfactory complaints by the end of the first month.Level of Evidence4 Laryngoscope, 131:E2475–E2480, 2021

Assessment of Olfactory Function in Children and Adolescents: An Overview.

Valid and reliable tools for assessing olfactory function are necessary for the diagnosis of olfactory dysfunction. Olfactory testing can be challenging in a pediatric population due to shorter attention span, linguistic development, and lower olfactory experience in this age group. The aim of this article is to present an overview about olfactory tests that are suitable for a pediatric population. Publications were included when reporting new developed methods of psychophysical olfactory testing in children or adaptation and applications of existing olfactory tests for a pediatric population. Olfactory tests for all 3 major aspects of olfactory function-olfactory threshold, odor discrimination, and odor identification-were included. Olfactory tests were evaluated regarding test validity, test reliability, normative data, and test availability. The current literature shows that several tests are available to assess olfactory function in children. Especially odor identification abilities in a pediatric population are well examined and understood. Tests for olfactory threshold and odor discrimination are less frequently used. In terms of the abovementioned evaluation criteria, only a few tests met all or 3 of these 4 criteria. Based on the current literature the following tests can be recommended for valid and reliable olfactory testing in children: "U-Sniff" odor identification test, the "Sniffin' Sticks" olfactory threshold test, pBOT-6 olfactory threshold and odor identification test, NIH-Toolbox, and Smell Wheel. Age has to be considered when evaluating olfactory function in children.

Evaluation of Olfactory Function in Children With Vernal Keratoconjunctivitis.

Vernal keratoconjunctivitis (VKC) is a chronic, severe allergic disease of the conjunctiva, which mostly affects young males in early to mid-childhood. There is a high incidence of asthma, allergic rhinitis (AR) and eczema among patients with VKC. It is unknown if VKC patients have abnormal olfactory dysfunction, and if so, whether this is related to AR. Our aim was to evaluate olfactory function in children with VKC, with and without comorbid AR, in comparison to healthy children without VKC. Thirty-nine VKC patients and 32 healthy children were included in the study. After eye and ear, nose and throat (ENT) examination, acoustic rhinometry and modified Connecticut Chemosensory Clinical Research Center (CCCRC) tests were performed and the test results were compared between VKC and control groups and between VKC children with or without AR. A p value <0.05 was regarded as statistically significant. The VKC group included 25 males (64.1%) with a mean age of 11.13 ± 3.22 years, while the control group included 26 males (81.3%) with a mean age of 12.50 ± 2.13 years (p > 0.05 for both age and gender). Fourteen VKC patients (35.9%) had either positive prick test or elevated serum specific IgE levels against house dust mites and pollens. Mean odor thresholds did not differ between the two groups (p = 0.084), while mean odor identification and CCCRC score were statistically significantly lower in VKC group (6.00 ± 1.02 and 6.81 ± 0.75, respectively) compared to control group (7.06 ± 0.77 and 7.5 ± 0.41, respectively) (p < 0.05, both). Thirteen VKC patients had co-associated AR (33.3%). In VKC patients with AR, mean odor threshold and identification scores were even lower (5.31 ± 0.95 and 6.23 ± 0.78, respectively) (p < 0.05, both). Olfactory function was found to be mildly impaired in children with VKC, especially when co-associated with AR. Therefore, loss of smell should be asked as an extraocular symptom.

The Influence of Cognitive Parameters on Olfactory Assessment in Healthy Children and Adolescents.

Olfactory threshold and odor identification tests are frequently used for assessment of olfactory function in children and adolescents. Whether olfactory test results are influenced by cognitive parameters or sex in children and adolescents is largely unknown. The aim of this study was to investigate the influence of cognition, age and sex on "Sniffin' Sticks" olfactory threshold and "U-Sniff" odor identification performance in a pediatric population. A total of 200 participants between age 6 and 17 years were included. Olfactory function (olfactory threshold and odor identification) was assessed using the "Sniffin' Sticks." In addition, age appropriate cognitive testing was applied. The results of this study indicate that odor identification test performance is positively correlated with age (r = 0.31) and verbal abilities of children (r = 0.24). Olfactory threshold results are only marginally influenced by age (r = 0.18) and are not associated with cognitive test performance. Olfactory assessment using olfactory threshold and "U-Sniff" odor identification testing is suitable for children and adolescents when considering age in the interpretation of test results.

The influence of a child's age on the evaluation of smells and their hedonistic assessment.

Olfactory function in children is most commonly evaluated using the odour identification test despite the fact that it is difficult to properly name odorants for young children. The goal of this study was to evaluate the pleasantness rating of odorants by children. The participants were 182 healthy children: the first group included 63 girls and 59 boys (aged 6-7) and the second included 31 girls and 29 boys (aged 11-12). We assessed olfaction using (1) standard method of odorant identification using a U-Sniff test and (2) classifying the hedonic tone of the odorants into 5 categories. The identification test's median differed in younger and older groups of children; the median was 8 and 10 respectively (p < 0.01). The unpleasant hedonic tones were butter, fish and onion. The pleasant hedonic tones were apple, orange and peach. The younger usually categorised hedonic tones as pleasant, compared with the older children, who categorised the odorant's hedonic tones more often as neutral (p < 0.01).Conclusion: This study demonstrated that older children are able to identify odours better than younger ones. The categorisation of hedonic tones differed depending on the subject's age. The younger children tended to categorise odorants as being pleasant and older children as neutral. What is Known: • The test of odour identification is the most popular because it is reliable, practical, rapid and commercially available. • The ability to identify odours improves with age in children. What is New: • The categorisation of hedonic tones differs depending on age. The older children categorise odorants as being neutral significantly more often than younger children do.

Characterizing Olfactory Function in Children with Autism Spectrum Disorder and Children with Sensory Processing Dysfunction.

Abnormalities in olfactory function have been identified in a number of neurological and psychiatric disorders, including Parkinson’s disease and schizophrenia. However, little is known about olfactory function in autism spectrum disorder (ASD). The present study aims to assess the olfactory profiles of children with ASD, compared to an age- and sex-matched comparison group of typically developing children and a second clinical control group consisting of non-ASD children with sensory processing dysfunction (SPD). Participants completed a battery of sensory and behavioral assessments including olfactory tasks (Sniffin’ Sticks Threshold Test and self-reported valence ratings for two target odorants (phenylethyl alcohol and vanillin) and the University of Pennsylvania Smell Identification Test), and an autism evaluation (Autism Diagnostic Observation Schedule-2). Children with ASD showed intact odor detection with reduced odor identification ability. Poor odor identification was significantly correlated with autism symptom severity. Children with SPD demonstrated reduced odor detection and identification ability. These findings provide evidence for differential patterns of smell processing among ASD and non-ASD neurodevelopmental disorders. Future studies are needed to determine whether the association of impaired olfaction and increased autism symptoms is due to shared etiology.

Influence of chronic diseases on the olfactory function in children.

The association between smell impairment and chronic diseases has been reported in some studies in adults. Such information is not available for chronic diseases in children. The aim of this study was to examine olfactory function of children with chronic diseases such as diabetes mellitus type 1, hypothyroidism, and bronchial asthma in combination with allergic rhinitis in comparison to healthy controls. The data were obtained from n = 205 participants (104 boys, 101 girls) between the age of 6 and 17years. Seventy-eight of the participants were healthy controls, n = 43 had diabetes mellitus type 1, n = 50 suffer from allergic rhinitis or bronchial asthma, and 34 presented a reduced function of their thyroid in medical history. All participants underwent olfactory testing including olfactory threshold using "Sniffin' Sticks" and odor identification using the "U-Sniff" test. In addition, a depression inventory and cognitive testing using the Ravens Progressive Matrices was performed. No significant difference in olfactory function was observed for any of the chronic diseases in children in comparison to healthy controls. Further analysis showed a trend in significance for a subpopulation of children with bronchial asthma and comorbidities performed worse on the olfactory threshold test compared to patients with bronchial asthma without comorbidities. Pediatric patients suffering from chronic diseases scored higher on the depression inventory compared to healthy controls.Conclusion: In conclusion, this study demonstrates that the influence of chronic diseases (bronchial asthma, diabetes mellitus type 1 and hypothyroidism) on olfactory function in childhood, if any, seems to be insignificant. This is partly in contrast to adult patients. Further research should be conducted in a subgroup of patients with bronchial asthma, allergic rhinitis, and atopic dermatitis or other comorbidities to better understand the association of allergic diathesis and olfactory function and the putative pathogenesis of olfactory dysfunction. What is known: • The association between smell impairment and chronic diseases has been reported in some studies in adults. • Such information is not available for chronic diseases in children. What is new: • The influence of chronic diseases (bronchial asthma, diabetes mellitus type 1, and hypothyroidism) on olfactory function in childhood, if any, seems to be insignificant. • In patients with bronchial asthma and allergic rhinitis, only a subgroup of patients with additional comorbidity (atopic dermatitis) showed a tendency to a reduced sense of smell.

FMRI correlates of olfactory processing in typically-developing school-aged children

Human olfactory processing is understudied relative to other sensory modalities, despite its links to neurodevelopmental and neurodegenerative disorders. To address this limitation, we developed a fast, robust fMRI odor paradigm that is appropriate for all ages and levels of cognitive functioning. To test this approach, thirty-four typically developing children aged 7–12 underwent fMRI during brief, repeated exposure to phenylethyl alcohol, a flower-scented odor. Prior to fMRI scanning, olfactory testing (odor detection and identification) was conducted. During fMRI stimulus presentation, odorant release was synchronized to each participant's inspiratory phase to ensure participants were inhaling during the odorant exposure. Between group differences and correlations between activation and odor detection threshold scores were tested using the FMRIB Software Library. Results demonstrated that our 2-min paradigm significantly activated primary and secondary olfactory regions. In addition, a significant relationship between odor detection threshold and higher activation in the right amygdala and lower activation in the left frontal, insular, occipital, and cerebellar regions was observed, suggesting that this approach is sensitive to individual differences in olfactory processing. These findings demonstrate the feasibility of studying olfactory function in children using brain imaging techniques.

Evaluation of olfactory function in children with seasonal allergic rhinitis and its correlation with acoustic rhinometry

ObjectivesSeasonal allergic rhinitis (SAR) is common in children and hyposmia is a major symptom affecting the quality of life. The aim of the present study is to assess olfactory dysfunction in pediatric patients with SAR and correlate the results with acoustic rhinometry measurements. MethodsForty children, diagnosed as moderate and severe SAR based on clinical findings, ARIA (Allergic rhinitis and it's impact on asthma) classification and prick test results were enrolled in the study. Endoscopic nasal examination, acoustic rhinometry, total nasal symptom score (TNSS) and Connecticut Chemosensory Clinical Research Center (CCCRC) tests were performed 'in season' (May–August) and 'out season' (November–February). Three patients who did not show up in 'out season' examinations were excluded from the study. ResultsThe ages of the children ranged between 8 and 18 years with a hyposmia increased and odor identification decreased (p < 0.005, p = 0.003, respectively), whereas no differences were found between odor thresholds and the discrimination values (p > 0.05). Mean CCCRC value was obstruction score (r =−0.340, p = 0.04), subjective hyposmia (r = −0.44, p = 0.007) and TNSS (r = −0.494, p = 0.02). Although some of the acustic rhinometry parameters were lower during allergy season, there were no correlations between acoustic rhinometry parameters and CCCRS values. ConclusionNearly half of the children with AR reported a mild to moderate hyposmia during pollen season and there was a decrease in odor identification, which can be easily shown using a CCCRC test.

Acquired Olfactory Dysfunction in Children and Adolescents: A Systematic Review of the Literature

Olfactory function can be influenced by many factors and olfactory dysfunction is associated with several diseases. But even considering this, the causes of acquired olfactory dysfunction in children are not well understood. This review was conducted to gain an overview of the etiologies of acquired olfactory dysfunction in a pediatric population. Studies were identified using a predefined literature search, including studies if patients were ≤18 years of age and results of psychophysical olfactory testing were reported. A total of 44 articles met the inclusion criteria for this review and were included in the qualitative analysis. The influence of 6 disease groups on olfactory function in children was observed (otorhinolaryngology, traumatic brain injury, oncology, psychiatric diseases, environmental factors, and other diseases). The current literature is convincing that diseases in the otorhinolaryngology group and traumatic brain injury can lead to acquired olfactory dysfunction, whereas according to the current literature, the role of other influencing factors such as most psychiatric disorders remains uncertain. A number of diseases and circumstances affect olfactory function in children and may cause acquired olfactory dysfunction in this age group. Nevertheless, more research is needed to better understand the causes of acquired olfactory dysfunction in children. Future research should have the goal of early diagnosis and, if possible, early treatment of the condition to prevent a negative impact of olfactory dysfunction on children and adolescents.

Development of an International Odor Identification Test for Children: The Universal Sniff Test

To assess olfactory function in children and to create and validate an odor identification test to diagnose olfactory dysfunction in children, which we called the Universal Sniff (U-Sniff) test. This is a multicenter study involving 19 countries. The U-Sniff test was developed in 3 phases including 1760 children age 5-7 years. Phase 1: identification of potentially recognizable odors; phase 2: selection of odorants for the odor identification test; and phase 3: evaluation of the test and acquisition of normative data. Test-retest reliability was evaluated in a subgroup of children (n = 27), and the test was validated using children with congenital anosmia (n = 14). Twelve odors were familiar to children and, therefore, included in the U-Sniff test. Children scored a mean ± SD of 9.88 ± 1.80 points out of 12. Normative data was obtained and reported for each country. The U-Sniff test demonstrated a high test-retest reliability (r27 = 0.83, P < .001) and enabled discrimination between normosmia and children with congenital anosmia with a sensitivity of 100% and specificity of 86%. The U-Sniff is a valid and reliable method of testing olfaction in children and can be used internationally.

Olfactory function in children with adenoid hypertrophy who underwent adenotonsillectomy during pre- and post-operative period

Objective: To assess the olfactory function in children with adenoid hypertrophy and investigate the changes of both olfactory function and appetite in children with adenoid hypertrophy before and after adenoidectomy. Methods: Forty-four children with adenoid hypertrophy admitted for adenoidectomy, aged 7-12 years, mean age (10.0±2.0) years were tested by Sniffin' Sticks test and visual analog scale(VAS) of the children's appetite preoperatively between March and August 2015.In a appointment 6 months after operation, all of them returned and were tested again. The control group consisted of 40 healthy children, aged 7-12 years, mean age (11.2±0.8) years.SPSS 13.0 software was used for statistical analysis Results: The olfactory function of the study group TDI scores (32.4±3.5) preoperatively were significantly lower in comparison with the results of the control group TDI scores (37.3±2.8)(t=7.057, P<0.001). Significant improvement of olfaction TDI scores (36.8±1.9) was observed in the follow-up appointment(t=13.573, P<0.001). The VAS of the children's appetite during post-adenoidectomy was higher compared to pre-adenoidectomy(t=16.765, P<0.001). There was a strong correlation between the increase in appetite of children and the change of TDI score (r=0.59, P<0.01). Conclusions: Children with adenoid hypertrophy have a reduced ability of both olfactory function and appetite. Surgery had a greater impact on olfaction and appetite.

Olfactory threshold and odor discrimination ability in children \u2013 evaluation of a modified \u201cSniffin\u2019 Sticks\u201d test

The clinical diagnostics of olfactory dysfunction in children turns out to be challenging due to low attention span, insufficient linguistic development and lack of odor experiences. Several smell tests have been developed for adults. Most of these examinations take a relatively long time and require a high level of concentration. Therefore, the aim of the current study was to evaluate an odor discrimination and olfactory threshold test using the frequently used “Sniffin’ Sticks” in children and adolescents in a simplified two-alternative-forced-choice version (2AFC) and compare it to the original three-alternative-forced-choice test (3AFC). One-hundred-twenty-one healthy participants aged between 5 and 17 years took part in this study. Within each of the two sessions participants underwent olfactory testing using the modified 2AFC as well as the standard 3AFC method. A better test-retest reliability was achieved using the original 3AFC method compared to the modified 2AFC. This was true for the odor discrimination as well as the olfactory threshold. Age had a significant influence on both tests, which should be considered when testing young children. We discuss these findings with relation to the existing norms and recommend using the 3AFC version due to a better test-retest reliability to measure olfactory function in children.

Changes in Olfactory discrimination associated to environmental Manganese in Adolescents

Introduction: Olfactory changes are frequently shown in Parkinsonian patients and may be related to dysregulation of Dopaminergic control. While studies have suggested that exposure to manganese (Mn) may be associated with Parkinsonism, there is limited information on Mn exposures and the olfactory function in children. Methods: We measured soil and house dust Mn levels in the household of 389 children in Brescia, Italy. Surface soil was assessed with a Niton pXRF instrument and dust samples were collected by sweeping a measured area with a plastic brush, or using a cyclone vacuum. Mn was determined with ICP-OES. To assess odor identification we used Sniffin’ Sticks-Olfactory Screening 12 test (Burghart Medical Technology). We examined the relationships of soil and indoor-outdoor dust Mn (log-transformed) with olfactory discrimination (log-odds of correct identification) using generalized linear models and generalized additive models, adjusting for age, sex, socioeconomic status index, mother education, smoking and drinking. We also tested the effect of environmental Mn using a generalized linear mixed effects model, that allowed us to estimate the difficulty associated with recognizing each of the 12 odors, taking into account the olfactory ability of each subject Results: We found that soil Mn (estimate=-0.125, p=0.02) indoor dust (-0.06, p=0.045) and outdoor dust Mn (estimate=-0.07, p=0.03) were associated with decreased odds of correct odor identifications. This effect was particularly evident in boys. Cloves (when compared with peppermint) was the most difficult odor to be recognized by boys and girls. Conclusions: Our findings suggest that higher environmental Mn levels measured in household dust, outdoor dust and soil may be associated with worse odor identification. These data support the potential influence of Mn on dopaminergic control of olfactory functions that may represent an early sign of neurotoxicity.

Evaluation of olfactory function in children with allergic rhinitis and nonallergic rhinitis

ObjectivesAllergic rhinitis (AR) occurs when the symptoms of rhinitis arise as a result of allergen-induced nasal mucosal inflammation. In the presence of rhinitis symptoms without infection or an allergic reaction in the nose, non-allergic rhinitis (NAR) is considered. Adults with these diseases have increased frequency of olfactory dysfunction. The aim of the present study is to assess olfactory function in children with AR and NAR. MethodsA total of 77 children (aged six to 18 years) with AR and NAR were included in the study. The control group consisted of 45 healthy children. Sniffin' Sticks test was applied to both groups. The association between odor scores and demographic, clinical, and laboratory results was investigated. ResultsForty two patients had allergic rhinitis. No significant difference was observed between patients with rhinitis and healthy controls with respect to odor scores. No association was observed between odor scores and the severity of rhinitis and the laboratory results of the patient groups. Odor identification and total odor scores of the patients with rhinitis lasting for longer than three years were significantly lower than those in the patient group with rhinitis lasting for one to three years. In the AR and control groups, the odor scores were found to increase with age. ConclusionsWhen compared with healthy children, children with allergic rhinitis and non-allergic rhinitis were not found to have reduced olfactory function. The duration of rhinitis may be associated with the olfactory dysfunction in children with rhinitis.