Transcript The role of environmental factors in allergies

The role
of environmental factors in
allergies
Prof. Witold Lukas
Department of Family Medicine,
Silesian Medical Academy
Risk factors increasing probability
of allergic sensitivity
• The time of exposure of internal and external
factors (pregnancy, the neonatal period, early
childhood).
• Different exposure (from the ones mentioned
above) to viral (an increased frequency of RSV)
and bacterial (a higher incidence of G-negative)
infections.
• Type and intensity of exposure to: pollen (from
plants or trees), mites, molds or tobacco smoke.
Internal risk factors augmenting
allergic sensitivity
• Pregnancy
Immunity switches from type Th1 to Th2 (at birth
neonates predominantly have type Th2).
• Breast-feeding
The milk of women with atopic diseases contains
decreased amounts of secretory IgA as well as
polyunsaturated fatty acids.
Internal risk factors augmenting
allergic sensitivity
• Newborns with atopic diseases
Delayed maturation of T and B lymphocytes. In
some cases – excessive production of IgE
precedes the onset of allergic symptoms.
Intestinal flora of a newborn:
– healthy – a predominance of Lactobacillus –
stimulating type Th1 in the immune system
– with atopic diseases – a deficiency of Lactobacillus
Reasons for recent changes in
exposure to different type of
viral and bacterial infections
• The consumption (from an early neonatal
period) of food prepared under sterile conditions.
• Improvement in personal hygiene, a lack of
common bacteria in the environment.
• Early application of broad-spectrum antibiotics.
• A significant decrease in the incidence of
infectious diseases, including mostly morbilli,
caused by the common use of vaccinations.
Reasons for recent changes in
exposure to different types of
viral and bacterial infections
• The improvement of household conditions
– a higher standard of living – better
sealing of windows in houses, worse
ventilation, the use of air conditioning,
augmenting exposure to molds.
• Fewer children in families.
• Decreased contact of children with their
peer groups.
The allergic march – the life cycle
of the allergy
0-6 mo - Predominance of gastro-intestinal
symptoms; possible skin lesions
7-12 mo - Symptoms of atopic dermatitis of
newborns; gastro-intestinal symptoms
2-3 yo - Asthma in early childhood
4-7 yo - Allergic rhinitis
8-14 yo - Bronchial asthma, allergic rhinitis
External risk factors causing
allergic sensitivity
• Pollen
Grass – timothy
Weeds – ragweed
Trees – birch, alder, oak
• Animal danders (pets – e.g. hamsters, cats)
• Industrial dusts and irritant gases (ozone, sulfur
dioxide, nitrogen oxide, formaldehyde)
• Automobile engine exhaust
Physical signs helpful in diagnosing
allergic diseases
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the allergic salute– ‘rubbing’ of the nose
A horizontal ‘groove’ on the nose
eye ‘shadows’
Denis-Morgan lines on the palpebrae
an adenoidal face
secretory otitis media
paranasal sinusitis
geographic tongue
Signs of allergies of the upper
respiratory tract
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Pruritus and tearing (lacrimation)
Sneezing ‘fits’
Nasal congestion
Clear exudate rhinitis
‘Scratching’ of the throat
Laryngeal dyspnea (shortness of breath)
Hypersensitivity to pollen
Pollen seasons:
• The end of Jannuary to the beginning of
March - e.g. alder
• April - e.g. birch, maple
• May to the end of June - e.g. grass
(including grain)
• August to September - e.g. weeds
Regional differences occur
Hypersensitivity to allergens
• Hypersensitivity to weeds – summer
• Hypersensitivity to dust mites – perennial,
with exacerbation during the winter season
(due to heating)
• Hypersensitivity to animal danders and
feathers – perennial or incidental
Allergies to grass & tree pollens
• Prophylactic actions:
– Avoid sleeping with an open window
– Avoid walking between 12:00 and 15:00
– Avoid driving with an open window
– Avoid bicycling
– Avoid exposure to smoke (due to burned
wood or grilled food)
Allergies to grass & tree pollens
• Recommendations
– Walking after the rain
– Wearing long sleeve shirts and trousers in case of
skin eruptions
– Daily shower or bath (and washing one’s hair) as well
as changing clothes after walking or outdoor activities
– Allowing air flow in the home during and after the rain
– Creating a self-monitoring flowchart
– Using Pollen Monitor available online at
http:/www.alergie.info.pl or by using the press, radio
and/or TV
– Using the European pollen calendar
Allergies to grass & tree pollens
• Recommendations
– Spending time in places containting (theoretically) small amounts
of pollen, e.g. closed pools, spaces without windows, places next
to large water reservoirs.
– When planning vacations, taking into consideration differences in
pollen seasons in various geographical regions of the country.
– Avoiding eating honey, drinking herbal teas, taking herbal
medications or using fragrant topical herbal creams or lotions.
– Conveying information about possible cross-allergies, e.g. birch
pollens.
– Avoiding strong fragrances – the elimination of bath/shower
lotions, herbal cosmetics, hair sprays and perfumes.
Dust mite allergies
• Signs and symptoms:
– Rhinitis
– Nocturnal cough
– Dyspnea (shortness of breath – SOB)
Perennial symptoms, with exacerbation
during the heating season, i.e. winter
(especially at night and in the morning).
Dust mite allergies prophylactic actions
• Recommendations for patients:
– Reducing high humidity at home and in the workplace
via installing a high efficiency air-filtering system or by
keeping proper air-flow.
– Changing bed sheets frequently (1x per week),
‘freezing’ bed sheets frequently during the winter,
using anti-allergic covers over the mattress and
pillows.
– Avoiding exposure to velveteen fabrics, furs, dustcollecting furniture, draperies, wool covers, carpets.
– Avoiding being present during house/office cleaning
and returning only after at least two hours post
cleaning or dusting.
Dust mite allergies prophylactic actions
• Recommendations for patients:
– Avoid staying in the attic or basement.
– Use the Acarex test to identify dust mites.
– Use Acarosan preparation topically on one’s
mattress, furniture fabrics, rugs and carpets
once every 4-6 months.
– Use Acaril liquid to rinse bed sheets that are
washed in temperatures up to 60oC.
Allergies to fungal spores
• Signs:
– Conjunctivitis (perennial with periods of
seasonal exacerbations)
– Nasal congestion (edema of nasal mucosa)
– Asthma
Signs and symptoms are perennial.
Patients allergic to outdoor fungal species
remain asympthomatic in the winter.
Allergies to fungal spores
• Prophylactic actions in the home/flat:
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Remove potted plants.
Remove or frequently change air humidifiers.
Avoid working in libraries, banks.
Avoid being present next to construction or demolition
sites.
Avoid picking mushrooms or forest walking after rain.
Exclude ‘blue’ cheese, dry fruit, mushrooms, wine and
beer from one’s diet.
Avoid staying in green-houses and compost prisms.
Avoid places with air conditioning.
Allergies to pet animal danders
• Mostly related to: hamsters, cats or birds
(parrots, canaries)
• Prophylactic actions:
– Removal of these pets/animals, especially
from the bedroom.
– Wash away cat dander.
Food allergy
Signs
• Skin
– Utricaria – acute & recurrent acute
• Respiratory tract
– Rhinitis, wheezing or difficulty with breaching
– Pharyngitis, laryngitis
– Otitis
– Bronchitis, chronic pneumonia
– Asthma
Food allergies
Signs
• Gastrointestinal (GI) tract
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Recurrent diarrhea or constipation
Abdominal pain
Colic pain in the neonatal period
Gastroesophageal reflux (GERD)
• The nervous system
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Fatigue, increased somnolence
Attention deficit disorders
Hyperactivity disorders, aggression
Headaches
Epilepsy
Food allergies
Signs
• The musculoskeletal system
– Pain in one’s extremities
– Joints edema
• The urinary system
– Proteinuria
– Hematuria
Cross-reactions between pollen and food
allergens (the presence of profiline in
pollens and foods)
Pollens and types of foods
Grass
Raw fruits or vegetables – apples,
carrots, potatoes, tomatoes
Alder, birch tree
Nuts, apples, peaches, pineapples,
carrots
Rye-grass
Rye flour
Weeds
Celery, melons, parsly, herbs
Latex
Bananas, kiwi, avocado
Genetically modified food (GMO)
• An allergy to corn with Plant Incorporated
Pepticide (PIP)
• An allergy to soya with the brasilian nut
gene
Nutrition for allergy
prophylaxis
• Breastfeeding - min. to 6 months
• A hypoallergic diet for lactating women – the exclusion
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Milk
Eggs
Nuts
Cacao
Fish
Citrus fruits
• A gluten-free and hypoallergic diet to 1 year
• A hypoallergic mix for neonates with a positive family
history of allergies