Clinical: Skin infections Flashcards
What are the two main presentations of Impetigo?
- Bullous Impetigo
- Non Bullous Impetigo
What is the difference in the causative organisms for bullous impetigo and non bullous impetigo?
Bullous: Staphylococcal Epidermolytic toxin Non Bullous: Staph Aureus or Streptococcus or both
Who does non bullous impetigo typically affect and during what time of year?
Young children often in late summer
What distribution of impetigo is seen in neonates?
Widespread
What are the predisposing factors for impetigo?
Minor skin abrasions and the existence of other skin conditions such as infestations or eczema
What is this?
Impetigo
Child presents with fever, irritability and skin tenderness. Erythema usually begins in the groin, axillae and around the mouth. Blisters and superficial lesions develop over 1-2days and can rapidly involve large areas with systemic upset. Diagnosis?
Staphylococcal Scalded Skin Syndrome
What is the difference between SSSS and Toxic Epidermal Necorosis
SSSS: splits beneath the stratum corneum
TEN: the whole epidermis is affected
What action should be taken in a patient with suspected SSSS?
Systemic antibiotics, immediate commencement of intensive support measures, rehydration, bacterial swabs should be taken from family members
What happens following SSSS?
Although the acute presentation is very severe, rapid recovery and absense of scarrig are usual as the epidermal spilt is superficial
Patient presents with fever, desquamating rash, circulatory collapse (low bp and hypotension) and multi-organ involvement…diagnosis?
Toxic Shock Sydrome due to Staph Aureus toxins
What is the difference between cellulitis and erysipelas?
- Cellulitis is inflammation of subcutaneous tissue, due to bacterial infection. It is typically ill defined and affects the leg.
- Erysipelas is bacterial infection of the dermis and upper subcutaneous tissue. It is typically well defined and affects the face
What is the diagnosis?
Cellulitis
- Hot, painful, erythematous and oedematous
- What is the diagnosis?
Erysipelas
- Most affected site is the face
Lesions with dome like, “umbilicated”, skin coloured papules with central punctum, often multiple and found at side of chest and inner arm
Molluscum Contagiosum
Lesions are erythematous, annular and scaly, with well defined edge and central clearing. There may also be pustules at the active edge. Lesions are usually assymmetrical and can be single or multiple.
Tinea Corporis. Caused by fungal infection.
Itchy rash between the toes with peeling, fissuring and maceration.
Athlete’s foot or Tinea Pedis
What is the difference between Herpes Simplex 1 and Herpes Simplex 2, and which is more prevalent?
HSV-1: involves the mucocutaneous surfaces of the head and neck. More prevalent.
HSV-2 predominantly involves the genital mucosa
-There may be some overlap
How do people become exposed to the Herpes Simplex Virus?
Infection is acquired by innoculation of viruses shed by an infected individual on to a mucosal surface in a susceptible person
-The virus infects sensory and autonomic neurons and establishes latent infection in the nerve ganglia. Primary infection is followed by reactivation throughout life.
What happens following exposure to HSV?
-The virus infects sensory and autonomic neurons and establishes latent infection in the nerve ganglia. Primary infection is followed by reactivation throughout life (producing cold sore).
- Caused by Coxsackie virus
- Relatively mild illness with fever and lymphadenopathy develops after an intubation period of about 10days. A painful papular or vesicular rash appears on palmopalantat surfaces of hands and feet. Diagnosis and management?
Hand, foot and mouth
-Antiviral treatment is not avaliable so managament consists of symptomatic relief: analgesics.
