Evaluation of Olfactory Function in Children With Vernal Keratoconjunctivitis

Abstract

Background 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. Objective Our aim was to evaluate olfactory function in children with VKC, with and without comorbid AR, in comparison to healthy children without VKC. Materials and Methods 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. Results 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). Conclusion 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.

Prevalence of allergic sensitization with vernal keratoconjunctivitis: A systematic review with meta‐analyses

“…De Oliveira et al ( 2006 ) found a positive skin prick test for at least one of the allergens tested in 75% of patients and a poor correlation between the clinical severity score and the sensitivity to the allergens. Elsurer et al ( 2021 ) reported that 36% had either a positive skin prick test or elevated specific IgE levels against house dust mites or pollens. Erdem et al ( 2011 ) reported mean total IgE levels were 496 IU/ml and a positive skin prick test for house dust mites or pollen in 30%, and a positive conjunctival or nasal provocation test in 26% and 22%, respectively.…”

“…Turkey (Bozkurt et al, 2010 , 2013 ; Elsurer et al, 2021 ): House dust mites ( Dermatophagoides farinae and Dermatophagoides pteronyssinus ), tree pollens, weed mix, grasses‐cereal, animal hair, moulds, and food allergens (egg and cacao). House dustmites [ D. pteronyssinus (Dp) and D. farinae (Df)], a mixture of grass pollens, a mixture of grain pollens, tree pollens, moulds, Cladosporium mixture, animal hair, and cockroach.…”

“…Most testing panels include house dust mites and animal dander (dog and cat), but more rare allergens can be present such as tobacco, pigeon feather, cockroach, ants, and other types of insects. Geographic differences across 5 different panels are listed below for comparison: Egypt (Abo‐Ali et al, 2015): House dust mites, animal dander (cat, dog, and horse), moulds, pollens, grass, wool, hay dust, straw, cotton dust, tobacco, pigeon feather, Candida, and American cockroach ( Periplaneta americana ). Turkey (Bozkurt et al, 2010, 2013; Elsurer et al, 2021): House dust mites ( Dermatophagoides farinae and Dermatophagoides pteronyssinus ), tree pollens, weed mix, grasses‐cereal, animal hair, moulds, and food allergens (egg and cacao). House dustmites [ D. pteronyssinus (Dp) and D. farinae (Df)], a mixture of grass pollens, a mixture of grain pollens, tree pollens, moulds, Cladosporium mixture, animal hair, and cockroach. Italy (Bonini et al, 2000): Rye grass, house dust mites, Parietaria, Olea, Artemisia, cat dander, and Alternaria allergens. Brazil (De Oliveira et al, 2006): House dust mites D. pteronyssinus , D. farinae , and Blomia tropicalis , as well as allergens from cat, dog, fungi, and feathers. Thailand (Kosrirukvongs et al, 2001): house‐dust mites, house dust, cockroaches, grass, insects, fungi, and food. …”

“…I G U R E 2 Forest plot of the meta-analysis of the prevalence of patients with vernal keratoconjunctivitis with a positive allergy test.other types insects. Geographic across different are listed below for comparison: Egypt(Abo-Ali et al, 2015): House dust mites, animal dander (cat, dog, and horse), moulds, pollens, grass, wool, hay dust, straw, cotton dust, tobacco, pigeon feather, Candida, and American cockroach (Periplaneta americana).• Turkey(Bozkurt et al, 2010(Bozkurt et al, , 2013Elsurer et al, 2021):House dust mites (Dermatophagoides farinae and Dermatophagoides pteronyssinus), tree pollens, weed mix, grasses-cereal, animal hair, moulds, and food allergens (egg and cacao). House dustmites [D. pteronyssinus (Dp) and D. farinae (Df)], a mixture of grass pollens, a mixture of grain pollens, tree pollens, moulds, Cladosporium mixture, animal hair, and cockroach.…”