Nutrition 1 and 2 - Pre-reading and SGW Flashcards
What is a food allergy in comparison to a food intolerance?
When symptoms are caused by an immune reaction
What type of antibody usually mediates a food allergy?
IgE (sometimes non-IgE - thought to be T cell mediated, but not well understood)
What is a food intolerance in comparison to a food allergy?
A non-immune reaction
What causes a lactose intolerance?
A lactase enzyme deficiency leading to poor breakdown of lactose in the GI tract - the excess unabsorbed lactose results in symptoms
What are symptoms and signs of an IGE-mediated food allergy which affect the skin? (4)
Pruritus
Erythema
Acute urticaria
Acute angioedema
What are signs and symptoms of a non-IgE mediated allergy that affects the skin? (3)
Pruritus
Erythema
Atopic eczema
What are signs and symptoms affecting the GI tract of an IGE-mediated food allergy? (6)
Angioedema of the lips, tongue and palate Oral pruritus Nausea Colicky abdominal pain Vomiting Diarrhoea
What are signs and symptoms of a non-IgE mediated food allergy which affect the GI tract? (10)
Gastro-oesophageal reflux disease Loos or frequent stools Blood and/ or mucus in stools Abdo pain Infantile colic Food refusal or aversion Constipation Perianal redness Pallor and tiredness Faltering growth in conjunction with at least one or more GI symptoms above
What are 2 groups of signs/ symptoms of an IgE mediated food allergy which affects the resp system?
Upper resp tract symptoms e.g. nasal itching, sneeze, rhinoorhea)
Lower rest symptoms e.g. cough, wheezing
What is 1 group of signs/ symptoms of an IgE mediated food allergy that affects the resp system?
Lower resp. symptoms e.g. cough, chest tightness
What type of food allergy causes signs/ symptoms of anaphylaxis or other systemic allergic reactions?
IgE mediated food allergies
A food allergy should be suspected in children and young people who’s symptoms do not respond adequately to treatment for what 3 illnesses?
Atopic eczema
Gastro-oesophageal regular disease
Chronic GI symptoms including chronic constipation
Give 3 examples of atopic diseases?
Atopic eczema
Asthma
Allergic rhinitis
In terms of acute/ non-acute and rapid/ delayed onset of symptoms, describe IgE and non-IgE mediated food allergies?
IgE - Rapid, acute
non-IgE - Delayed, non-acute
If an IgE-mediated allergy is suspected in a child/ young person, what tests should be offered to them?
A skin prick test and/ or blood tests
If a non-IgE mediated allergy is suspected, what treatment/ tests should be offered to the patient?
Trial elimination of the suspects allergen (normally for between 2 - 6 weeks) and reintroduce after the trial
What is thought to case the reduced mechanical strength of skin in obesity?
A failure of collagen deposition to match the increased surface area
Why does the skin tend to be dry in obese patients?
Increased trans-epidermal water loss
What causes irritation between skin folds in obese patients?
Increased activity of apocrine and eccrine sweat glands in enlarged skin folds increases moisture/ skin maceration and friction in folds
How does microvascular dysfunction in obese patients lead to hypertension?
It results in increased skin blood flow
What effect does obesity have on lymphatics?
Pressure from fat impedes lymphatic flow and causes leakage of protein rich lymphatic fluid into subcutaneous tissues
How can obesity lead to increased hormone production?
The endocrine roles of adipose tissues may be altered leading to increased hormone production e.g. testosterone
How does obesity affect sebaceous glands?
Increased androgens (male sex hormones) produced in peripheral fat stimulate sebaceous glands
What is the name for the velvety thickening and pigmentation of the skin folds, usually axillae?
Acanthosis nigricans
What is frequently found around the neck and axillae of obese patients?
Skin tags (acrochordons)
What 2 direct skin manifestations of obesity are associated with insulin resistance?
Acanthosis nigricans Skin tags (acrochordons)
What is the name for increased hair in females in male distribution due to obesity?
Hirsutism
Why do patients with obesity frequently get acne?
Due to increased sebaceous gland activity
What is the name for a chronic inflammatory disease where boils and abscesses form and scar in apocrine gland areas esp. axillae, groin)? - seen in obese patients
Hidradenitis suppurativa
What is the name for male pattern balding in men/ women? - seen in obese patients
Androgenetic alopecia
What are stretch marks? What is the proper name for this?
Type of warring associated with dermal connective tissue injury in response to local stretching forces
Striae distensae
What is the sequence of events that leads to obese patients legs becoming grossly enlarged?
Increased subcutaneous fat causes reduced lymphatic drainage leading to swelling
Gradually worsening swelling causes chronic inflammation leading to fibrosis
Reduced tissue oxygenation and swelling results in bacterial overgrowth
Cellulitis develops easily and leads to further lymphatic damage
A downward spiral develops if left untreated and ultimately the skin becomes thick and warty and the lower leg and foot become permanently enlarged, often grossly
What is the sequence of events in chronic venous insufficiency that leads in venous ulceration in obese patients?
Abdominal obesity resists venous return from the legs
Veins dilate and valves become incompetent, varicose veins develop
The increased hydrostatic pressure in the vessels results in red blood cell leakage into tissue resulting in swelling, haemosiderin pigmentation and inflammation (due to breakdown products)
Chronic scarring eventually occurs
The skin may ulcerate (venous stasis ulceration)
What are 5 skin diseases aggravated by obesity?
Lymphoedema Chronic venous insufficiency Skin infections Intertigo Psoriasis
What is intertrigo?
Macerated red plaques which develop in skin folds due to high moisture levels, friction, increased pH and reduced barrier function that are prone to secondary infection
What role does vitamin A play in terms of the skin?
Vital for epithelial proliferation, keratinisation and development
What are the sources of vitamin A?
Animal - milk, liver, eggs, oily fish
Plant - green leafy veg, bright yellow/ orange fruit and veg
How does a vitamin A deficiency present in terms of the skin?
Keratotic follicaular papules on the thighs and upper arms, dry skin
How to diagnose a vitamin A deficiency?
Measure serum vitamin A
What is vitamin K essential for?
Several blood coagulation factors
What are the main sources of vitamin K?
Green leafy veg, liver, legumes, vegetable oils (also produced in GI tract by bacteria - therefore can be affected by prolonged antibiotics)
Presentation of vitamin K deficiency?
Bleeding tendency, seen in skin as proper and easy bruising
How to diagnose a vitamin K deficiency?
Measure coagulation and serum Vitamin K
What is another name for Vitamin B2?
Riboflavin
What is the role of vitamin B2 (riboflavin)?
Essential co-factor in numerous metabolic reactions
What are the sources of vitamin B2 (riboflavin)?
Milk, liver, meat, eggs, green leafy veg
What are the signs of a vitamin B2 (riboflavin) deficiency?
Lesions of the margins of the lips (chalices) and corners of the mouth (angular stomatitis)
Painful red dry tongue
How do you diagnose a vitamin B2 (riboflavin) deficiency?
Measure the activity coefficient of erythrocyte glutathione reductase (EGR)
What is another name for Vitamin B3?
Niacin
What is the role of vitamin B3 (niacin)?
Essential co-factor in numerous metabolic reactions
What are the sources of vitamin B3 (Niacin)?
Meat, fish, nuts, coffee
Also converted from dietary tryptophan (essential amino acid) in the body
What are the symptoms/ signs of a vitamin B2 (Niacin) deficiency?
Pellagra: dermatitis (worse on sun exposed areas) Delirium Diarrhoea - with abdo pain, vomiting Death - in 4-5 years if not treated
Diagnosis of vitamin B3 deficiency?
Clinical diagnosis, as difficult to measure niacin levels
Nicotinamide supplementation brings rapid improvement
What is the role of Vitamin B6?
Co-enzymes for many processes
What are the source of vitamin B6?
Meat, cereals, milk, potatoes, banks, nuts and pulses
Symptoms of a vitamin B6 deficiency?
Dermatitis of face, scalp, neck, shoulders, buttocks and perineum, tongue inflammation (glossitis)
Diagnosis of a vitamin B6 deficiency?
Measure serum or urinary Vitamin B6
Trial of supplement
What is the role of folate?
Critical co-enzyme
What are the sources of folate?
liver, green leafy veg, beans, nuts and milk
Symptoms/ signs of a folate deficiency?
Anaemia, angular stomatitis, glossitis, hair depigmentation, sin and mucous membrane pigmentation
Diagnosis of a folate deficiency?
Measure serum folate
Role of vitamin B12?
Critical co-enzyme
Sources of vitamin B12?
Only found in foods of animal origin such as meat, milk, fish and eggs
Signs/ symptoms of a vitamin B12 deficiency?
Anaemia, angular stomatitis, glossitis, hair depigmentation, sin and mucous membrane pigmentation
Role of biotin?
Essential co-factor for carboxylase enzymes
Sources of Biotin?
Cereals, meat, milk, eggs, pulses, nuts - also produced by GI bacteria
Presentation of biotin deficiency?
Rare - facial dermatitis, glossitis, alopecia
Diagnosis of a biotin deficiency?
Serum biotin
Other name for vitamin C?
Ascorbic acid
Role of vitamin C?
Essential co-factor in collagen formation
Sources of vitamin c?
Citrus fruit, strawberries, balckcurrants, tomatoes, potatoes
Presentation of a vitamin C deficiency?
hYperkeratosis around hair follicles, bent hairs, inflamed gums, poor wound healing - fatigue, malaise, muscle and bone pain
Diagnosis of a vitamin C deficiency?
Clinical - supplements bring a rapid improvement
Role of zinc?
Required for many metabolic pathways - required for structure and function of skin and so vital for wound healing
Sources of zinc?
Meat, fish, milk, eggs, cereals, nuts and pulses
Presentation of a Zinc deficiency?
Genetic = acrodermatitis enteropathica (autosomal recessive) - caused by a lack of zinc absorption = diarrhoea, alopecia dry/ brittle hair, perioral, facial and aural dermatitis
Acquired - more common, and may be due to increased elimination of zinc secondary to burns or infection - dermatitis rash of hands and feet mainly
Diagnosis of a zinc deficiency?
Serum zinc measurement
What are the 2 forms of protein energy malnutrition?
Mrasmus
Kwashiorkor
What is Marasmus?
Blobal nutrient deficincy causing weight loss by fat breakdown
Appearance of a child with Marasmus?
Very thin and muscle wasting
No oedema
Skin is dry, wrinkled and lose from subcutaneous fat and muscle loss
Hair is thin, brittle and can cause alopecia
What is Kwashiorkor caused by?
Very low protein intake with reasonable carbohydrate intake
Appearance of a child with Kwashiorkor?
Oedema is present and children often develop an enlarge pot bello
Skin looks irregular or patchy discolouration caused by pigmentary change
Dark, dry skin amy split when stretched revealing pale areas between the cracks (crazy, paving dermatosis)
What is the proper name for piriton?
Chlorphenamine
Is he prick test or blood tests more definitive for diagnosing an IgE mediated allergy?
prick tests are more definitive
what can cause a prick test to show a false negative?
If the patient has ingested anti-histamines
Is it common for food to play a role in adult eczema?
Very uncommon (Very common in children)
How to insert an epipen?
"Blue to sky, orange to the thigh" Remove blue cap Push into thigh Hold for 10 secs Remove and massage area
