Background: Despite all research published in the last decades, the prevalence of
food allergy in the paediatric population has continued to increase and is nowadays
recognized as a significant public health problem. In the United Kingdom, studies
have found that between 2.2% and 5.5% of the infants in the first year of life present
with proven food allergies, with the prevalence of cow’s milk protein allergy, the most
common form of non-IgE food allergies, ranging between 1.9% and 4.9%. The
diagnosis of non-IgE mediated food allergy is a real challenge due to its delayed
onset, with symptoms occurring hours to days after ingestion of the culprit and
mainly affecting the gastrointestinal tract. Allergy tests have shown limited use in
these patients, and the diagnosis relies heavily on the recognition of symptoms and
an allergy-focused history. The treatment is based on diet elimination, which can
lead to the development of nutritional disorders and negative impact on the child’s
quality of life.
Objectives: The aims of the publications included in this thesis are, first, to
prospectively investigate the required length of elimination diet to achieve symptom
improvement during the diagnostic process; second, to evaluate the knowledge of
primary health care professionals about diagnosis and management of cow’s milk
protein allergy, to compare with parents views and opinions, and to better
understand diagnosis tools, treatment and tolerance in infants diagnosed with nonIgE food allergies; third, to evaluate possible impacts of the elimination diet on
growth and nutrients deficiencies; and fourth, to analyse the potential impact of nonIgE mediated gastrointestinal allergies on the quality of life of the affected children
and their families.
Methods: Children with suspected non-IgE mediated gastrointestinal food allergies
were recruited and followed prospectively at a large tertiary gastroenterology
department in the United Kingdom (UK) from December 2011 to November 2013.
This study was designed to investigate the impact of non-IgE mediated food allergies
on quality of life, as well as to establish symptoms, children’s growth and the
characteristics and impact of dietary elimination. The knowledge and journey of
diagnosis of cow’s milk protein allergy among general practitioners were studied via
surveys. Eosinophilic colitis in infants was studied through a systematic review.
II
Results: In non-IgE mediated gastrointestinal food allergies the required time to
achieve symptom improvement following the initiation of the elimination diet was four
weeks in 98% of our patients. All symptoms individually and collectively have
statistically improved after commencing the elimination diet (p <0.001). Regarding
cow’s milk protein allergy, parents and general practitioners have very different
perceptions about the course of the disease and the families’ journeys. An extensive
review of the literature found that eosinophilic colitis occurred more frequently in
male infants, younger than six months old. Half were exclusively breastfed at the
time of the diagnosis. Patients on a diagnostic four-week elimination diet showed an
improvement in the weight-for-age and weight-for-height. It was also noted that 60%
of the cohort had low vitamin D intake and a higher number of patients had a low
intake of copper, zinc, and selenium. Non-IgE mediated food allergies have a
negative impact on the quality of life of the affected children and their families.
Conclusions: The “Discovering the effect of non-IgE mediated allergies on children
and their families” is a landmark study in the paediatric food allergy field. This welldesigned study investigated and elucidated some important characteristics and
clinical features of this group of patients. Its impact is reflected in the number of
publications derived from the results of this cohort, a large number of citations and
the impact in clinical practice worldwide as much more is now known about this
condition. Studies investigating preventative measures for the development of food
allergies in childhood are also essential in the future