General Knowledge Flashcards
Gell and Coombs Hypersensitivity Type 1 (Anaphylactic)
Antigen reacts with IgE bound to mast cells
• Anaphylaxis
• Atopy (e.g. asthma, eczema and hayfever)
Gell and Coombs Hypersensitivity Type 2 (Cell Bound)
IgG or IgM binds to antigen on cell surface • Autoimmune haemolytic anaemia • ITP • Goodpasture's syndrome • Pernicious anaemia • Acute haemolytic transfusion reactions • Rheumatic fever • Pemphigus vulgaris / bullous pemphigoid
Gell and Coombs Hypersensitivity Type 3 (Immune Complex)
Free antigen and antibody (IgG, IgA) combine
• Serum sickness
• Systemic lupus erythematosus
• Post-streptococcal glomerulonephritis
• Extrinsic allergic alveolitis (especially acute phase)
Gell and Coombs Hypersensitivity Type 4 (Delayed Hypersensitivity)
T-cell mediated • Tuberculosis / tuberculin skin reaction • Graft versus host disease • Allergic contact dermatitis • Scabies • Extrinsic allergic alveolitis (especially chronic phase) • Multiple sclerosis • Guillain-Barre syndrome
Gell and Coombs Hypersensitivity Type 5
Antibodies that recognise and bind to the cell surface receptors.
This either stimulating them or blocking ligand binding • Graves’ disease
• Myasthenia gravis
Mesenteric Ischaemia
Predisposing factors
- increasing age
- atrial fibrillation
- other causes of emboli: endocarditis
- cardiovascular disease risk factors: smoking, hypertension, diabetes
- cocaine: ischaemic colitis is sometimes seen in young patients following cocaine use
Features
- abdominal pain
- rectal bleeding
- diarrhoea
- fever
- bloods typically show an elevated WBC associated with acidosis
Management
- supportive care
- laparotomy and bowel resection
Renal Stone Types
- Calcium oxalate (40%, Opaque)
- Mixed calcium oxalate/phosphate stones (25%, Opaque)
- Triple phosphate stones (10%, Opaque)
- Calcium phosphate (10%, Opaque)
- Urate stones (5-10%, Radio-lucent)
- Cystine stones (1%, Semi-opaque, ‘ground-glass’ appearance)
- Xanthine stones (<1%, Radio-lucent)
Charcot’s Triad
Charcot’s triad of right upper quadrant (RUQ) pain, fever and jaundice occurs in about 20-50% of patients with ascending cholangitis.
- Fever is the most common feature, seen in 90% of patients
- RUQ pain 70%
- Jaundice 60%
Hypotension and confusion are also common
Vaccinations (live attenuated)
- BCG
- Measles, mumps, rubella (MMR)
- Influenza (intranasal)
- Oral rotavirus
- Oral polio
- Yellow fever
- Oral typhoid
Vaccinations (inactivated preparations)
- Rabies
- Influenza (intramuscular)
Vaccinations (detoxified exotoxins)
- Tetanus
Vaccinations (extracts of the organism)
- Diphtheria
- Pertussis (‘acellular’ vaccine)
- Hepatitis B
- Meningococcus, pneumococcus, haemophilus
Third Nerve Palsy Features
- Eye is deviated ‘down and out’
- Ptosis
- Pupil may be dilated (sometimes called a ‘surgical’ third nerve palsy)
Addison’s (adrenal insufficiency) Features
- Lethargy, weakness, anorexia, nausea & vomiting, weight loss, ‘salt-craving’
- Hyperpigmentation (especially palmar creases), vitiligo, loss of pubic hair in women, hypotension
- Crisis: collapse, shock, pyrexia
Primary Hyperaldosteronism Features
- Hypertension
- Hypokalaemia (e.g. muscle weakness)
- Alkalosis
Normal Pressure Hydrocephalus Features
A classical triad of features is seen:
- Urinary incontinence
- Dementia and bradyphrenia
- Gait abnormality (may be similar to Parkinson’s disease)
Vitamin A
Retinoids
Night-blindness (nyctalopia)
Vitamin B1
Thiamine
Beriberi
- polyneuropathy, Wernicke-Korsakoff syndrome
- heart failure
Vitamin B3
Niacin
Pellagra
- dermatitis
- diarrhoea
- dementia
Vitamin B6
Pyridoxine
Anaemia, irritability, seizures
Vitamin B7
Biotin
Dermatitis, seborrhoea
Vitamin B9
Folic acid
Megaloblastic anaemia, deficiency during pregnancy - neural tube defects
Vitamin B12
Cyanocobalamin
Megaloblastic anaemia, peripheral neuropathy
Vitamin C
Ascorbic acid
Scurvy
- gingivitis
- bleeding
