The "Sniffin' Kids-PT" test: A smell test variant for Portuguese children

OBJECTIVE

Olfactory tests tailored for children are essential, as diagnosing olfactory dysfunction at these ages can be challenging. The 16-item "Sniffin' Sticks" is reliable and easy to perform. To the best of our knowledge, there is currently no validated olfactory test for the Portuguese pediatric population. This study aimed to adapt and validate the "Sniffin' Sticks" olfactory test for the Portuguese pediatric population.

METHODS

Between August 2020 and September 2021, 354 children aged between 6 and 17years old enrolled in the study, 336 healthy children with a normal sense of smell, and 18 anosmic children with Kallmann syndrome. The study consisted of two parts. Firstly, the "Sniffin' Sticks" olfactory identification test was applied to healthy children and the odors with statistically significant low identification rates were excluded. A modified version of "Sniffin' Sticks" was defined and named "Sniffin' Kids-PT" test. Secondly, normative data were assessed and test-retest and validation tests were performed.

RESULTS

Apple and Cloves odors were identified with a low rate and were excluded from the "Sniffin' Sticks" olfactory test. In the modified 14-item "Sniffin' Kids-PT", scoring <6 (from 6-8years old), <7 (from 9-11years old) or <8 (from 12-14years old and 15-17years old) was indicative of olfactory dysfunction. The test-retest reliability was good (r=0.81; P<0.001) and the differences between scores of healthy children and anosmic children were statistically significant (U213=13.00; P<0.001).

CONCLUSION

The modified "Sniffin' Kids-PT" is a reliable test to discriminate between normosmia and olfactory dysfunction in Portuguese children over 5years old.

Development of parallel forms of a brief smell identification test useful for longitudinal testing

Although there are numerous brief odor identification tests available for quantifying the ability to smell, none are available in multiple parallel forms that can be longitudinally administered without potential confounding from knowledge of prior test items. Moreover, empirical algorithms for establishing optimal test lengths have not been generally applied. In this study, we employed and compared eight machine learning algorithms to develop a set of four brief parallel smell tests employing items from the University of Pennsylvania Smell Identification Test that optimally differentiated 100 COVID-19 patients from 132 healthy controls. Among the algorithms, linear discriminant analysis (LDA) achieved the best overall performance. The minimum number of odorant test items needed to differentiate smell loss accurately was identified as eight. We validated the sensitivity of the four developed tests, whose means and variances did not differ from one another (Bradley-Blackwood test), by sequential testing an independent group of 32 subjects that included persons with smell dysfunction not due to COVID-19. These eight-item tests clearly differentiated the olfactory compromised subjects from normosmics, with areas under the ROC curve ranging from 0.79 to 0.83. Each test was correlated with the overall UPSIT scores from which they were derived. These brief smell tests can be used separately or sequentially over multiple days in a variety of contexts where longitudinal olfactory testing is needed.

Alpha-lipoic acid does not improve olfactory training results in olfactory loss due to COVID-19: a double-blind randomized trial

OBJECTIVES

Olfactory loss is a recognized long-term dysfunction after Coronavirus Disease 2019 (COVID-19) infection. This investigation aimed to assess the effect of alpha-lipoic acid as an adjuvant treatment of olfactory training on the improvement of smell loss in post-COVID-19 patients.

METHODS

This randomized controlled trial included 128 adult outpatients who had persistent smell loss for more than 3-months after COVID-19 infection. The participants were randomly allocated into two groups: the intervention treatment group, which received alpha-lipoic acid associated to olfactory training, and comparison treatment group, which received placebo pills associated to olfactory training. The participants were followed-up for 12-weeks. Olfactory dysfunction was assessed in terms of Visual Analog Scale (VAS), and the Connecticut Chemosensory Clinical Research Center (CCCRC) test for the Brazilian population.

RESULTS

A total of 100 participants completed the follow-up period and were analyzed in this study. Both groups have improved CCCRC score (p = 0.000), olfactory threshold (p = 0.000), identification score (p = 0.000) and VAS score (p = 0.000) after 12-weeks follow-up. No significant differences were determined between the intervention and comparison treatment groups in CCCRC score (p = 0.63), olfactory threshold (p = 0.50), identification score (p = 0.96) and VAS score (p = 0.97). In all these criteria, comparison treatment group went slightly worse. At the endpoint of the study, the frequency of anosmia reduced to 2% in the intervention treatment group and to 7.8% in the comparison treatment group. Also, 16.8% of the intervention group' subjects, and 15.7% of comparison treatment group's patients reached normosmia.

CONCLUSIONS

Overall, there was a strongly significant difference in olfactory function between baseline and endpoint for both groups. However, based on the lack of significant difference between the intervention treatment and the comparison treatment groups in terms of olfactory changes, our study appoints that the alpha-lipoic acid is not better than olfactory training alone to treat olfactory loss after COVID-19.

LEVEL OF EVIDENCE

Level 2.

Olfactory dysfunction in Japanese children with moderate-to-severe allergic rhinitis

OBJECTIVE

Detailed quantitative studies on olfaction remain inadequate in patients with paediatric allergic rhinitis (AR). This study examined olfactory dysfunction in children with AR.

METHODS

From July 2016 to November 2018, children aged 6-9 years were recruited and grouped as AR (n = 30) or without AR (control group, n = 10). Odour identification was evaluated by the Universal Sniff (U-Sniff) test and the Open Essence (OE). The results were compared between the AR and control groups. Intranasal mucosa findings, nasal smear eosinophil counts, blood eosinophil counts, total immunoglobulin E (IgE) levels, Japanese cedar-specific IgE and Dermatophagoides pteronyssinus-specific IgE were evaluated in all participants. Additionally, the presence of sinusitis and adenoid hypertrophy in patients with AR was also evaluated by sinus X-ray examinations.

RESULTS

The median U-Sniff test scores were not significantly different between the AR and control groups (9.0 vs. 10.0, respectively; p = 0.107). The OE score was significantly lower in the AR group than in the control group (4.0 vs. 8.0; p = 0.007, respectively), especially in the moderate-to-severe AR group versus the control group (4.0 vs. 8.0; p = 0.004). Furthermore, in the OE, the correct answer rates for 'wood', 'cooking gas' and 'sweaty socks' were significantly lower in the AR group than in the control group.

CONCLUSIONS

Paediatric AR patients can reduce olfactory identification ability, and the degree may be associated with the severity of AR in nasal mucosal findings. Furthermore, olfactory dysfunction may slow down the response to 'emergency situations', such as gas leak.

Olfactory Training Impacts Olfactory Dysfunction Induced by COVID-19: A Pilot Study

INTRODUCTION

Olfactory dysfunction is one of the main symptoms of COVID-19 and may last beyond resolution of the infection. The most promising intervention for post-viral olfactory dysfunction is olfactory training (OT), which involves exposing the olfactory system to a range of odors daily. This approach is thought of promoting the regeneration of olfactory receptor cells, but its effectiveness in patients with post-COVID-19 olfactory dysfunction has yet to be confirmed.

METHODS

This double-blind randomized pilot study compared the effectiveness of OT versus placebo in the treatment of post-COVID-19 olfactory dysfunction. Twenty-five participants were recruited in each group. OT protocol consisted of sniffing 4 scents (rose, orange, clove, and eucalyptus) for 5 min twice daily for 12 weeks. Olfactory function was assessed before and after the training using (1) a validated odor identification test (UPSIT-40) and (2) a 10-point visual analog scale; we further assessed the presence of (3) parosmia.

RESULTS

While we did not observe any effect of OT on olfactory test scores, we observed a significant improvement of subjective olfactory function in the intervention group, while no such effect was observed in the placebo group. Finally, the frequency of parosmia was significantly lower in the intervention group.

CONCLUSIONS

This study highlights an increase in subjective but not objective olfactory function when performing OT for 12 weeks. Further, parosmia seems to be positively affected by OT. These results may serve as a starting point for larger scale studies to assess the efficacy of OT for treatment of post-COVID-19 olfactory dysfunction.

Validation of the local applicability of the 'TIB' Olfactory Test Device in the era of COVID-19

Objective

To evaluate the validity and test–retest reliability of the novel ‘TIB’ Olfactory Test Device (TIB) and to determine its normative values.

Methods

The study stratified the study subjects into normosmic, hyposmic and anosmic groups according to their olfactory function. The olfactory function of the subjects was evaluated using both the traditional Chinese version of the University of Pennsylvania of Smell Identification Test (UPSIT-TC) and the TIB. The normosmic group was used to retest with the UPSIT-TC and TIB at an inter-test interval of at least 7 days. The cut-off scores of TIB among the three different groups were determined by receiver operating characteristic curve analysis.

Results

This study enrolled 180 subjects: 60 in each group. The mean scores of TIB were 44.1 for the normosmic group, 27.5 for the hyposmic group and 10.9 for the anosmic group. The TIB scores were significantly different across the three groups. There was a significant correlation between the first and second TIB tests (r = 0.506). The cut-off scores were 41 for normosmic subjects and 24 for hyposmic subjects.

Conclusion

The validity and test–retest reliability results suggest that the TIB is an appropriate olfactory test for the Taiwanese population.

Comparison of the Healing Effect of Nasal Saline Irrigation with Triamcinolone Acetonide Versus Nasal Saline Irrigation alone in COVID-19 Related Olfactory Dysfunction: A Randomized Controlled Study

There is no routinely determined treatment for olfactory dysfunction because of COVID-19. Saline irrigation and nasal corticosteroid treatments are safe and inexpensive methods, and have low side effects. In our study, we argue that saline nasal irrigation and topical corticosteroid treatment can be used in the treatment of patients with olfactory loss in all areas of rhinology. A total of 150 patients who admitted to our clinic with other symptoms or with only acute odor loss, diagnosed with COVID-19 with RT-PCR were divided into 3 equal groups.Fifty patients in Group 1 were not given any extra treatments. The other 50 patients in Group 2 were given saline irrigation for treatment; and the 50 people in Group 3 were given both saline irrigation and nasal steroid spray for treatment. The “Subjective Olfactory Capability (SOC)” was used for olfactory function evaluation of patients. Self-Rating Olfactory Score (SROS), and Olfactory Dysfunction Duration (ODD) were recorded on the 1st, 15th and 30th days. SROS of the group receiving Nasal Saline + Triamcinolone Acetonide treatment on the 30th day was significantly higher than in other groups (p^−1–3 = 0.018, p²⁻³ =0.033). Also, the ODD was significantly reduced in this group compared to other groups (p^−1–3 =0.022, p²⁻³ =0.028,). Topical triamcinolone treatment was found to be successful in the treatment of olfactory dysfunction due to COVID-19. Nasal steroids, which are both inexpensive and have low side effect profiles, can be used safely in the treatment of patients with olfactory losses.

Olfactory Dysfunction is Associated with More Severe Clinical Course in COVID-19

To perform a quantitative olfactory test in positive COVID19 RT-PCR admitted patients and asymptomatic ones, to evaluate the association between hyposmia and disease severity. This is a Cross sectional study. Ninety-one patients including 68 inpatients and 23 asymptomatic healthcare workers with positive COVID-19 RT-PCRs. Methods: Demographics and clinical characteristics were collected. Iran Smell Identification Test (IR-SIT), a highly accurate 6-odorant test was used to evaluate the reliability of self-reported hyposmia and determine the correlation of the measured olfactory dysfunction with disease severity. Twenty-two of 91 patients (24%) reported hyposmia, while 41/91 (45%) patients had measurable olfactory dysfunction (IR-SIT score 1–4, p < 0.05). Mean age of the 68 inpatients and 23 asymptomatic patients were 43.97 ± 16.13 years; M:F 43:25, and 43.87 ± 12.76 years; M:F 8:15 respectively. Of 68 patients, 20 were graded as severe, and 48/68 had mild course of disease. IR-SIT detected hyposmia in 80% of patients with severe disease, and 50% with mild disease, respectively. The risk of disease severity was significantly increased for patients with olfactory dysfunction and was detected 4 times higher when compared to patients with mild disease (OR 4, 95% CI: 1.166–13.728, p = 0.028). Olfactory Dysfunction was present in 80% of patients with severe course. The risk of disease severity is significantly increased with olfactory dysfunction in admitted patients.

Validation of a new olfactory test for Chinese Parkinson's disease patients

INTRODUCTION

Hyposmia is a common non-motor symptom in Parkinson's disease (PD) and has been used to assist PD diagnosis and early screening of prodromal patients. Although the Brief Smell Identification Test (B-SIT) is the most commonly used olfactory test, its utility was limited by the culture difference in recognition of the smells included in the test. We have developed a new modified B-SIT test for Chinese (B-SITC), and validated and compare it with B-SIT in Chinese PD patients.

METHODS

From 2015 to 2018, PD patients were recruited from the Movement Disorder Clinic of Xuanwu Hospital and healthy controls were recruited from the Beijing Longitudinal Study on Aging Cohort II. The two olfactory tests were used in healthy volunteers and PD patients.

RESULTS

A total of 428 subjects participated in the study: 211 healthy controls and 217 PD patients. The average B-SIT and B-SITC scores were significantly different between control and PD groups (B-SIT, 9.18 ± 1.94 vs. 6.90 ± 2.44, P = 0.0001; B-SITC, 8.60 ± 1.93 vs. 5.91 ± 2.21, P = 0.0001). The B-SITC had good sensitivity (73.1%), specificity (76.8%), positive predictive value (76.8%), and negative predictive value (73.1%) for the diagnosis of Chinese PD, and the area under the curve (AUC) value was greater for the B-SITC than for the B-SIT (0.838 vs. 0.761).

CONCLUSIONS

The B-SITC is useful for the clinical assessment of olfactory function in Chinese PD patients.

First recognized n-butanol concentration may be simple and useful index for assessing olfactory dysfunction in geriatric patients

The KVSSII is widely used to evaluate olfactory function in the Korean population. We evaluated the usefulness of the first recognized n-butanol concentration, which is obtained at the beginning part of KVSS II, in predicting olfactory dysfunction. Three hundred seventy two subjects were enrolled in our study. The results of KVSS II and the demographic characteristics were statistically analyzed. The first recognized n-butanol concentration was positively correlated with the result of KVSS II. The mean value of first recognized n-butanol concentration was 5.59 ± 1.42 in normosmia, 4.10 ± 1.40 in hyposmia, and 0.84 ± 1.68 in the anosmia group. By ROC curve, cut-off value of 2.5 showed sensitivity of 85.9% and specificity of 90.6% for anosmia, and cut-off value of 4.5 showed sensitivity of 77.6% and specificity of 69.8% for hyposmia. Consequently, we suggest that it may be useful in assessing olfactory function, in geriatric patients who are not able to tolerate conventional KVSS II.

Kallmann syndrome in pediatric otorhinolaryngology practice - Case report and literature review

BACKGROUND

Kallmann syndrome (KS) is an isolated form of hypogonadotrophic hypogonadism (HH) in combination with a defect in olfactory function. The diagnosis of KS before maturation is often difficult to make due to the broad spectrum of presentation and genetic heterogeneities. ENT examination including smell test is essential for proper diagnosis of olfactory disturbances and non olfactory abnormalities in craniofacial region which may also be existent in KS.

CASE

A 17-year-old girl admitted to ENT Department because of the olfactory sense disturbances since two years. The patient reported also amenorrhea caused by primary HH. A diagnostic work-up using double-checked Sniffin' Sticks test and 6-items olfactory test confirmed serious hyposmia and identified the presence of KS.

CONCLUSION

Usually anosmia is not recognized by the affected individuals, so it is recommended to perform olfactory screening tests and obligatory ENT examination in the event of a HH even when patient reports a normal sense of smell. It leads to early diagnosis of KS and will benefit the relevant patient care.The KS diagnosis should be done at an early stage, but symptoms and clinical manifestations are not always evident both in ENT and pediatric field. In this article we would like to highlight the need for a multidisciplinary assessment and awareness for KS symptoms in pediatric practice as a hole.

Newly developed method for mouse olfactory behavior tests using an automatic video tracking system

OBJECTIVE

The mouse is the most popular animal model in olfactory research. Behavior tests with odorants are essential for determining olfactory phenotype. To the best of our knowledge, the mouse olfactory behavior test has not been standardized, making the results vulnerable to inter-observer variation. We sought to develop a new mouse olfactory behavior test assessed by an automatic video tracking system with minimal inter-observer variation.

METHODS

A video-tracking system was used to automatically track mouse behavior in standard breeding cages with C57BL/6N mice. We tested two odorants (peanut butter for the preference test, 2MB acid for the avoidance test) and distilled water (for a control). Mouse behavior was recorded for 3min and analyzed. For the preference test, investigation time was measured. For the avoidance test, time spent in sectors away from the odorant zone was measured. To confirm our experimental settings, we also evaluated an anosmia mouse model prepared with intranasal administration of ZnSO₄.

RESULTS

All strains of mice showed reproducible behavior patterns of preference or avoidance for the odorants. The anosmia mouse model, as expected, failed to show an olfactory ability for preference or avoidance, and this was well-matched by histologic changes caused by the ZnSO₄ treatment. The automatic video tracking system successfully tracked and automatically calculated mouse behavior with good reproducibility.

CONCLUSION

Our olfactory behavior test offers a simple and accurate method to evaluate olfactory function in mice. This test can be utilized as a possible standard method to search for features of olfactory phenotypes in mice.

Olfactory identification test using familiar distracters for koreans

Objectives

Odors used in an odor identification test should be familiar to the subject, but there are some unfamiliar distracters in Korean version of Sniffin' stick (KVSS) II identification test. In this study, we used the results of the original version of KVSS II identification to modify the KVSS II identification test.

Methods

Eighty-three participants took an original version of KVSS II identification test and a visual analogue scale of subjective odor function. KVSS II identification which has 16 items was performed to choose one out of four odors items. And visual analogue scale was checked from 0 to 10 points of their subjective olfactory function. Two weeks later they took the modified version of KVSS II identification test. Hyposmic or anosmic patients were excluded.

Results

The mean score of the original version of KVSS II identification and modified version of KVSS II identification were 11.3 and 12.5, respectively (P<0.05). The KVSS II identification test and subjective olfactory function were positively correlated (r=0.247, P<0.05), as were the modified KVSS II identification test and subjective olfactory function (r=0.329, P<0.05).

Conclusion

After modification of distracters, KVSS II identification test appears to be suited for assessment of olfactory function.

Connecticut (CCCRC) Olfactory Test: Normative Values in 426 Healthy Volunteers

Application of Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test to healthy Turkish volunteers, obtain normative data set and analyse the role of age, sex and smoking on olfactory scores. The present study was conducted at Bezmialem Vakif University, Department of Otorhinolaryngology. Total of 426 healthy volunteers were subjected to CCCRC olfactory test which consists of n-butanol smell threshold test and smell identification test. Olfactory function score was assessed (0: worst score; 7: best score) and mean scores were calculated. Mean age was (36.7 ± 11.1; range, 17-68). 46.2 % of the subjects were male and 53.8 % were female; 37.1 % were smokers and 62.9 % were non-smokers. Mean n-butanol threshold score was 6.36 out of 7, mean identification score was 6.34 and mean total score was 6.35. According to CCCRC score: there were no anosmic individuals, 0.5 % were severely hyposmic, 2.6 % were moderately hyposmic,15.3 % were mildly hyposmic and 81.6 % were normosmic. CCCRC olfactory test is cost-effective, simple and practical. It can be easily applied in clinical settings. The CCCRC olfactory test is appropriate for assessment of olfactory function: Turkish population is familiar in terms of the odors used in CCCRC test. The power of this study is that it provides a normative data set against which many factors can be compared.