Corresponding author
Artesani Maria Cristina, M.D.
Translational Specialized Pediatrics Research Area, Allergic
Diseases Research Unit, Bambino Gesù Children’s Hospital, IRCCS, Rome,
Italy
Address: Piazza San’Onofrio, 4 00165 Rome, Italy
Email address:
mariac.artesani@opbg.net
Phone: +390668592309
Authors disclose any Conflict of interests related to the manuscript
content.
Authors disclose any financial support for the manuscript.
To the Editor,
Vernal keratoconjunctivitis (VKC) is a rare inflammatory-allergic
disease of the cornea and conjunctiva1. Immunologic,
genetic2 and environmental factors3,
such as light exposure, have been supposed to play a role in the
pathogenesis of ocular inflammation and in the worsening of VKC. In fact
VKC prevalence is highest in sunny and hot places and it is almost
absent in countries with short sunlight exposure, supporting the
hypothesis of a pathogenic role of sunlight exposure in the development
of this condition 4,5. Theoretically, in order to
estimate the real impact of sunlight exposure in the pathogenesis of
VKC, patients should not be exposed to sunlight. In real life, this
would have remained an impossible scenario to reproduce, until the
lockdown period imposed by the Italian Government to tackle the
SARS-CoV-2 pandemic. In fact, children in Italy remained confined to
their homes from March 5th to the end of May 2020 when
free movement was re-admitted. Italian children, forced to stay indoor,
spent many hours in front of bright screens which entails combination of
watching TV, playing video games, and/or using smartphone and PC, also
due to the E-learning initiatives.
The purpose of this study was to evaluate the “lockdown effect” on
VKC, that is to verify if the subjects who were forcibly sheltered from
sunlight showed VKC symptoms anyway; in addition, we investigated
whether the hours spent in front of the light produced by the bright
screens influenced the extent of the symptoms, in condition of almost
zero sunlight exposure.
As reported elsewhere6, in the Vernal
Keratoconjunctivitis Multidisciplinar Outpatient of Bambino Gesù
Children’s Hospital clinical data, instrumental ophthalmological
objectivity, and quality of life are systematically collected. We
retrospectively reviewed the data of patients with VKC evaluated from
June 2020 to July 2020, which had already been visited from March 2019
to July 2019. Children and adolescents aged between 5 to 12 years with
previous diagnosis of VKC, based on clinical history and slit lamp
examination of the anterior segment of the eye (presence of mild to
severe giant papillary reaction at the upper tarsal conjunctiva and/or
at limbus and/or presence of Horner-Trantas dots), were included. All
patients were diagnosed in both years before starting any specific
therapy, except unsuccessful topical antihistamine treatment. Only four
patients were in continuous treatment with immunosuppressive eye drops
due to the presence of chronic symptoms: three used topical cyclosporine
A and one topical tacrolimus eye drops.
Caregivers were asked for the availability of a garden in their homes
and for the number of hours per day spent in front of a bright screens.
Subjective symptoms were evaluated by a predefined 0-to-10 Visual
Analogue Scale (VAS) to score the presence of photophobia, tearing,
ocular itching and mucous ocular secretions and a VAS total score was
calculated (from 0 to 40).
Clinical severity of VKC and Health Related Quality of Life (HRQoL) were
evaluated according to Bonini grading scale and to Italian version of
the QUICK questionnaire,
respectively7,8.
The study was authorized by our local Ethics Committee.
Statistical analysis was performed using the statistical software R (R
Core Team, version 4.0.3). Changes in the overall distribution according
to clinical severity (Bonini grading scale) were analyzed by Fisher’s
exact test. Linear mixed effect regression models were devised using thelme4 package to measure the effects of different parameters
(hours of E-learning, difference in average time spent in front a
computer screen between 2020 and 2019, and availability of a garden) on
pain and HRQoL, with each subject being included as a random variable.
Statistical significance was set at p <0.05.
Twenty-nine male subjects (mean ± SD age: 8.74 ± 2.40 years) with VKC
were included in the study. No statistically significant effects were
found for any of the “surrogate” markers of light exposure (Symptom Δ
across years, garden available, Δ screen time between years) regarding
total VAS (table 1). Similarly, no statistically significant effects
were found for changes in Total Quick score between 2019 and 2020 in
regard to the variables included in the study (table 2).Overall, the
severity of symptoms, as expressed by the Bonini grading scale, did not
significantly differ between 2019 and 2020 (p = 0.2725) (table 3).
However, we expected these results because we visited the patients in
both years during the active phase of the VKC.
In order to verify whether the subjects who were forcibly sheltered from
sunlight had the symptoms anyway, we excluded from the analysis patients
who have a house with a garden (4/29) and which may have been exposed to
sunlight anyway.
Overall, 10 patients (34.4%) benefited from the lack of exposure to
sunlight because presented symptoms only upon re-exposure to it and no
one had more severe symptoms than the previous year. Indeed, one half of
the patients had milder symptoms when reported an increase in hours in
front of bright screens ≤ 4 times compared to 2019 (average increase
1.35 hours/day); with a 4+ times increase, patients experienced symptoms
of the same entity of the previous year (average increase 5.75
hours/day), effectively eliminating the beneficial effect of the lack of
exposure to sunlight.
Interestingly, also in the patients with VKC recurrence during lockdown
period (15/25) the number of hours spent in front of light sources seem
to be a determinant factor of worsening of symptoms. In fact, in 73.3%
(11/15) an average increase of 4.09 hours is related to symptoms more
severe or of the same severity of the previous year. Furthermore the six
patients (24%) who complain more severe symptoms in 2020 spent more
hours in front of light screens than in 2019 and compared to patients
who had milder symptoms in 2020.
To the best of our knowledge, this study is the first which aimed at
evaluating the impact of sunlight and light bright screens on VKC: only
in VKC-like Disease adult patients with more vision-related activities
(computer, photography) was reported the worst productivity index during
the active phase of the disease9.
During lockdown period 93.6% of people experienced an increase in their
digital device usage per day: the students have logged an average
increase in usage of digital devices of 5.18 ± 2.89 hours per day with a
statistically significant increase in number, frequency and intensity of
digital eye strain symptoms since the lockdown was
declared10.
These data are in line with ours: in fact, even our patients spent a
mean of 1.95±1.79 hours/day using PC or bright screens in 2019 and
4.14±2.49 hours/day in 2020 (p = 0.048). Interestingly, also in our
study this resulted in a worsening of ocular VKC symptoms (6/25) or at
least symptoms of the same severity as in spring 2019 (11/25) even in
those who, thanks to the reduced exposure to sunlight in spring 2020
compared to that of 2019 (0 months against 3 months) had managed to have
no symptoms until re-exposure to sunlight (5/11).
We can conclude that exposure to non-specific triggering factors such as
sunlight and bright light screens is a favoring factor for conjunctival
inflammation in VKC. Our results suggest that use of sunglasses, hats
with visors and swimming goggles should be recommended, as well as the
reduction of time spent in front of bright light sources such as
smartphones, computers, television in children with VKC.
KEYWORDS : Allergy diagnosis; Quality-of-Life; Vernal
Keratoconjunctivitis
Maria Cristina Artesani, M.D.
Translational Specialized Pediatrics Research Area, Allergic Diseases
Research Unit, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
Address: Piazza San’Onofrio, 4 00165 Rome, Italy
Email address:mariac.artesani@opbg.net