NNutrition Flashcards
Difference between food allergy and food intolerance
- Allergy = symptoms caused by immune reaction, usually IgE mediated
- Intolerance - non-immune reaction
Signs + symptoms of food allergy
- Pruritus
- Erythema
- Acute angioedema
- Nausea/Vomiting
- Abdo pain
- Diarrhoea
Investigation done for child with recurrent severe reactions to food
Serum specific IgE
Direct skin manifestations of obesity
-hirsuitsm
- acne
- striae distensae (stretch marks)
- skin tags
- androgenetic alopecia (balding)
- hidradenitis suppurativa
- acanthosis nigricans
What is acanthosis nigricans
nutritirtion- 2b
nutritirtion- 2c
Nutrition - 3
Impact of obesity on skin glands
Sebaceous- increased androgens production in peripheral fat which stimulate these glands
Apocrine + eccrine glands - there’s increased activity in enlarged skin folds which increases moisture/skin maceration and friction in folds increases irritation
Impact of obesity on skin barrier function
Increased trans-epidermal water loss therefore skin tends to be dry
Impact of obesity on collagen structure and function and wound healing
Decreased mechanical strength of skin due to failure of collagen deposition to match increased SA
Impact of obesity on subcutaneous fat
Adipose tissue’s endocrine roles may be altered as there’s an increase in hormone production (eg testosterone )
Impact of obesity on lymphatics
Lymphatic flow is impeded due to pressure from fat. Protein-rich lymphatic fluid leaks into subcutaneous tissues
Impact of obesity on circulation
Micro vascular dysfunction => increased blood flow to skin => hypertension
Skin diseases aggravated by obesity
- Lymphoedema
- Chronic Venous Insufficiency
- Skin Infections
- Intertigo
- Psoriasis
Explain obesity’s link to lymphoedema
pathophysiology
- Increased subcutaneous fat causes reduced lymphatic drainage => swelling
- Gradually worsening swelling causes chronic inflammation => fibrosis
- Decreased tissue oxygenation + swelling => bacterial overgrowth
- Cellulitis develops easily + causes further lymphatic damage
- If untreated, skin becomes thick + warty and lower leg + foot become permanently enlarged
Chronic venous insufficiency link to obesity
- Abdominal obesity resists venous return from leg
- Veins dilate + valves become incompetent, varicose veins develop
- Hydrostatic pressure in vessels increases causing rbc leakage into tissue => swelling, haemosiderin pigmentation + inflammation
- Chronic scarring
- Skin may ulcerate - venous ulceration
Why are obese people more at risk for skin infections
Increased tendency for bacterial, fungal + yeast infections
where are skin infections commonly seen in obese people
skin folds + areas where circulation is affected (Eg. legs)
explain intertigo association with obesity
- Macerated red plaques develop in skin folds due to high moisture levels, friction, increased pH and reduced barrier function
explain psoriasis link with obesity
Unclear link
Flexural psoriasis = aggravated by obesity
Where are skin tags frequently seen
axillae + neck
What is hidradenitis suppurativa
A chronic inflam disease where boils + abscesses form + scar in apocrine gland areas
Where is hidradenitis suppurativa commonly seen
axillae + groin
