Emergencies Flashcards
What may be the cause of urticuria (hives), angioedema, anaphylaxis?
Idiopathic Food- nuts, sesame seeds, shellfish, dairy Drugs- penicillin, contrast media, NSAIDS, morphine, ACE-I Insect bites Contact- latex Viral or parasitic infections Auto-immune Hereditary
What is urticuria due to?
A local increase in permeability of capillaries and small venules
A large no. of inflammatory mediators- prostaglandins, leukotrienes, chemotactic factors play a role but histamine derived from skin mast cells is the major mediator.
Local mediator release from mast cells can either be induced by immunological or non immunological mechanisms
How does urticuria present?
itchy wheals- swelling involving the superficial dermis, raising the epidermis
How does angio-oedema present?
This is a deeper swelling involving the dermis and subcutaneous tissues, it causes swelling of the tongue and lips
How does anaphylaxis present?
This is also known as anaphylactic shock
Results in-
Bronchospasm
Facial and laryngeal oedema
Hypotension
can present initially with urticaria and angioedema
What is the management for urticaria, angio oedema and anaphylaxis?
Urticuria- antihistamine ie: cetirizine
Angio-oedema- corticosteroids (these can also be used in sever acute urticaria)
Adrenaline, corticosteroids and antihistamines are all used for anaphylaxis.
What are the complications of urticaria, angio-oedema and anaphylaxis?
Urticaria is normally uncomplicated
Angio-oedema and anaphylaxis can lead to asphyxia, cardiac arrest and death
What is erythema nodosum?
A hypersensitivity response to a variety of stimuli
What are the causes of erythema nodosum?
Group A beta haemolytic streptococcus Primary tuberculosis Pregnancy Malignancy Sarcoidosis IBD Chlamydia Leprosy (chronic progressive bacterial infection)
What is the presentation of erythema nodosum?
Discrete tender nodules which may become confluent
Lesions continue to appear 1-2 weeks and leave bruise like discolouration as they resolve
Lesions do not ulcerate and resolve without atrophy or scarring
What are the main site for erythema nodosum?
The shins are the main site!
What is erythema multiforme?
An cute self limiting inflammatory condition
Herpes simplex virus is the main precipitating factor
Other infections and drugs are also causes
Mucosal involvement is absent or limited to only one mucosal surface
What is Stevens-Johnson syndrome?
Rare but serious disorder that affects the skin, mucous membrane, genitals and eyes
It is usually caused by an unpredictable adverse reaction to certain meds and sometimes can be caused by an infection
The syndrome begins with flu like symptoms, followed by a red or purple rash that spreads and forms blisters, the affected skin eventually dies and peel off.
What are the causes of steven johnson syndrome?
In children it is usually triggered by a viral infection..
- mumps
- flu
- herpes simplex virus
- coxsackie virus
- epstein barr virus (causes glandular fever)
Less commonly bacterial infections can trigger the syndrome
In adults, steven johnson syndrome is often caused by an adverse reaction to medicine
- allopurinol, carbamazepine, lamotrigine, nevirapine, phenytoin, sertraline, sulfasalazine
How does steven johnson syndrome typically present?
Flu like symptoms present during the initial stages
Aftera few days a rash appears, which consists of indicidual blemishes, that may look like a target
The rash isn’t usually itchy and spreads over a number of hours or days
Large blisters develop on the skin after the rash which leave painful sores after bursting
Facial swelling and swollen lips covered in crusty sores are common features
The mucous membranes inside your mouth, throat, eyes and genital tract may also become blistered and ulcerated (this can lead to dehydraton :(
The surface of the eyes can also be affected, which can cause corneal ulcers and vision problems if they are not treated quickly.
How do you manage steven johnson syndrome/toxic epidermal necrosis?
First step is to stop taking the mediations causing steven johnson syndrome
Analgesia- help ease raw areas of skin
Cool, moist compresses held against the skin
Regularly applying a plain (unscented) moisturiser to the skin
Replacement fluids
Mouthwashes with anaesthetic or antiseptic to make swallowing easier
Short course of corticosteroids (topical)
Abx (if sepsis)
Eyedrops or eye ointment (for eye symptoms)
What is toxic epidermal necrolysis?
This is usually drug induced,
causes full skin thickness separation
It is a variant of the steven johnson syndrome
How does staphylococcus scalded skin syndrome present?
Usually affects infants 3-7 days old
presents with erythematous bullae all over containing clear fluid which frequently rupture
Preceded by a staph aureus infection
What anti-epileptic is most likely to cause Steven Johnson syndrome?
Phenytoin
What is meningococcal disease?
This is an illness caused by the bacteria neisseria meningitidis
The two common presentations are meningococcal meningitis (infection of the membranes surrounding the brain and spinal cord) and meningococcemia (infection of the bloodstream)
What are the features of meningitis?
Headache, fever, neck stiffness
symptoms of septicaemia- hypotension, fever, myalgia, typical rash
Non blanching purpuric rash on the trunk and extremities
What is the management of acute meningococcaemia?
Ceftriaxone
For children- Treat children younger than 3 months with suspected bacterial meningitis without delay using intravenous cefotaxime plus either amoxicillin or ampicillin.
Prophylactic abx (rifampicin) for close contacts (ideally within 14 days of exposure
What are the complications of meningococcaemia?
Septicaemia shock
DIC
Multi organ failure
Death :(
What is erythroderma? (Red skin)
Inflammatory skin disease with erythema and scaling which affects nearly all the cutaneous surface.
What are the causes of erythroderma?
Previous skin disease- eczema, psoriasis
Lymphoma
Drugs (Sulphonamides, gold, sulphonylureas, penicillin, allopurinol, captopril) and idiopathic
What is the presentation of erythroderma?
Skin appears inflamed, oedematous and scaly
Systemically unwell with lymphadenopathy and malaise
What is the management of erythroderma?
Treat underlying cause, if known
Emollients and wet wraps to maintain skin moisture
Topical steroids to relieve inflammation
What are the complications of erythroderma?
secondary infection fluid loss and electrolyte imbalance Hypothermia High output cardiac failure Capillary leak syndrome (most severe)
What is the prognosis for erythroderma?
largely depends on the underlying cause
the overall mortality rate ranges from 20-40%
What is eczema herpeticum?
This is a widespread eruption- serious complication of atopic eczema or less commonly other skin conditions
Caused by herpes simplex virus
What is the presentation of eczema herpeticum?
Extensive crusted papules
blisters
erosions
systemically unwell with fever and malaise
How do you manage eczema herpeticum?
Antivirals (Aciclovir)
Antibiotics for bacterial secondary infection