Dermatology Flashcards
What is Roseola Infantum also known as, and what is it caused by?
Exanthem subitum, sixth disease, caused by HHV6
In what age of patients does Roseola Infantum present?
6 months to 2 years old
What is the incubation period of Roseola Infantum?
1-2 weeks
After the incubation period of Roseola Infantum, what is the presentation?
- High grade fever lasting 3-5 days → Febrile convulsions in 10%
- Maculopapular rash (AFTER FEVER)
- Bulging fontanelle
- NAGAYAMA SPOTS (Uvulopalatal spots)
- Periorbital oedema
- Cervical, occipital, postauricular lymphadenopathy
- Acute otitis media
- Rhinorrhoea, cough
- Diarrhoea and vomiting
How long does the Maculopapular rash last for in Roseola Infantum?
Can last for 1-2 days, but can disappear within 2-4 hours
How is Roseola Infantum diagnosed?
- Clinical diagnosis based on history
- May be aided with PCR to test for HHV6
How is Roseola Infantum treated?
Supportive management i.e. fluids, antipyretics
What is the consensus of school exclusion for Roseola Infantum?
- School exclusion is not necessary
What is the main complication of Roseola Infantum?
Febrile seizures
What is Slapped Cheek Syndrome also known as, and what is it caused by?
Erythema infectiosum, fifth disease, caused by Parvovirus B19
What is the incubation period of Slapped Cheek Syndrome?
4-14 days
After the incubation period of Slapped Cheek Syndrome, what is the presentation?
- Mild flu-like symptoms
- AFTER viraemia: Slapped cheek rash sparing mouth (circumoral pallor), palms and soles and reticular rash on body, plus arthralgia and arthritis
How might the presentation of Slapped Cheek Syndrome differ to those with underlying comorbidities?
- Immunosuppressed patients → Pancytopenia
- SCD / HS / Thalassemia patients → Aplastic crises
- In foetus’ → Hydrops fetalis, foetal loss in early pregnancy
How long does the rash last for in Slapped Cheek Syndrome?
Usually peaks for a week, however can re-appear on triggers such as a warm bath, sunlight, heat or fever in next few months
How is Slapped Cheek Syndrome diagnosed?
- Clinical diagnosis based on history
- Test IgG and IgM levels against Parvovirus B19 (especially in pregnant women)
- PCR for Parvovirus B19 (especially immunocompromised patients with low Ig levels)
If a pregnant woman has been exposed to Slapped Cheek Syndrome, what is recommended?
- Check IgM and IgG levels against Parvovirus B19
What is the management of Slapped Cheek Syndrome?
- Majority of cases are mild and resolve on their own
- Treat aplastic crises with blood products / IV Ig
- Treat polyarthralgia / arthritis with NSAIDs
What is the consensus of regarding time off school for Slapped Cheek Syndrome?
School exclusion is NOT necessary
What is fourth disease known as?
Duke’s disease
What is Duke’s disease known as?
Fourth disease
What is Rubella also known as? What is it?
German measles, it is a viral infection caused by Rubella virus
What is the incubation period of Rubella?
When are outbreaks more common?
14-21 days
Winter and spring
What is the presentation of Rubella?
- Prodrome → Low-grade fever
- Mild erythematous rash (compared to measles), starts on face → rest of the body
- SUBOCCIPITAL AND POSTAURICULAR LYMPHADENOPATHY
What is the risk of damage to a foetus if the mother has been infected with Rubella?
As high as 90% in the first 8-10 weeks, and damage is rare after 16 weeks
What is the management of a pregnant women with suspected cases of Rubella?
- Suspected cases should be discussed immediately with the local Health Protection Unit (HPU)
- IgM antibodies are raised in women recently exposed to the virus
- Congenital Rubella syndrome is a triad of?
- Deafness, blindness, congenital heart disease
Is the Rubella vaccine safe to take in pregnancy?
- NO, it is live attenuated vaccine. Must give postnatally
What are complications of Rubella?
- Thrombocytopenia
- Encephalitis
- Myocarditis
- Arthritis
What is Scarlet Fever?
A reaction to toxins produced by Group A haemolytic streptococci (usually Streptococcus pyogenes)
How is Scarlet Fever spread?
Via respiratory route by droplets or by direct contact with nose and throat discharges
What is the age of onset of Scarlet Fever?
2-6 years, with a peak at 4 years old
What is the incubation period of Scarlet Fever?
2-4 days
What is the presentation of Scarlet Fever?
- RASH:
- Fine punctate erythema (‘pinhead’) which appears first on the torso and spares palms and soles
- Children have a flushed appearance plus circumoral pallor. The rash is often more obvious in the flexures
- Rough ‘sandpaper’ texture
- Desquamation later in the course of illness, particularly around the fingers and toes
- Fever: typically lasts 24 to 48 hours
- Malaise, headache, nausea/vomiting
- Sore throat
- ‘Strawberry’ Tongue
How do you investigate suspected Scarlet Fever?
A throat swab normally taken, but antibiotic treatment should be commenced immediately rather than waiting for results
How is Scarlet Fever managed?
- Oral Penicillin V for 10 days
- If Pencillin allergy → Azithromycin
- Notify Public Health England
What is the consensus of regarding time off school for Scarlet Fever?
Children can return to school 24 hours after commencing antibiotics
What are the complications of Scarlet Fever?
- Otitis media (MOST COMMON)
- Rheumatic fever → 20 days after infection
- Acute glomerulonephritis →10 days after infection
- RARE → Meningitis, necrotising fasciitis
What is Measles?
A viral disease caused by RNA Paramyxovirus
What is the incubation period of Measles?
10-14 days
How is Measles spread?
By droplet infection
What are the features of Measles?
- Prodrome: irritable, conjunctivitis, fever (Fever + 4 C’s: cough, conjunctiva, coryzal symptoms, Koplick spots)
- Koplik spots (before rash): white spots on buccal mucosa
- Rash: starts behind ears 3-5 days after fever → whole body, discrete maculopapular rash becoming blotchy & confluent (cephalocaudal progression)
What are the investigations to diagnose Measles?
IgM antibdies
What is the management of Measles?
Supportive management
Notify Public Health England
What are the complications of Measles?
- Otitis media: the most common complication
- Pneumonia: the most common cause of death
- Encephalitis: typically occurs 1-2 weeks following the onset of the illness)
- Subacute sclerosing panencephalitis: very rare, may present 5-10 years following the illness
- Febrile convulsions
- Keratoconjunctivitis, corneal ulceration
- Diarrhoea
- Increased incidence of appendicitis
- Myocarditis
How should the contacts of a Measles patient be managed?
- If a child not immunized against measles comes into contact with measles then MMR should be offered
- This should be given within 72 hours
What are the six Viral Exanthemas?
- First disease → Measles
- Second disease → Scarlet Fever
- Third disease → German Measles / Rubella
- Fourth disease → Dukes Disease
- Fifth disease → Slapped Cheek / Erythema Infectiosum / Parvovirus B19
- Sixth disease → Roseola Infantum / Exanthem Subitum / HHV6
What is Eczema? Describe a brief pathophysiology
- A chronic atopic condition caused by defects in the continuity of the skin barrier. These defects allow irritants, microbes and allergens to create an immune response, leading to inflammation of the skin
Where is Eczema commonly seen in infants, younger children and older children?
- In infants the face and trunk are often affected
- In younger children eczema often occurs on the extensor surfaces
- In older children a more typical distribution is seen, with flexor surfaces affected and the creases of the face and neck
What are poor prognostic factors of Eczema?
- Onset at age 3-6 months
- Severe disease in childhood
- Associated asthma or hay fever
- Small family size
- High IgE serum levels
What is the maintenance therapy for Eczema?
- Emollients, as thick and greasy are possible particularly after washing and before bed
- Avoid activities which break down the skin barrier such as bathing in hot water, scratching, rubbing. Avoid soaps which strip the skin of oils. Use soap substitutes
How is Eczema flare-up managed?
- Thick Emollients & Topical Steroids: large quantities should be prescribed (e.g. 250g / week), roughly in a ratio of with topical steroids of 10:1
- If a topical steroid is also being used the emollient should be applied first followed by waiting at least 30 minutes before applying the topical steroids
- Wet wraps may be used
- Specialist treatments in severe eczema → zinc impregnated bandages, topical tacrolimus, phototherapy and systemic immunosuppressants, such as oral corticosteroids, methotrexate and azathioprine
Give examples of thin emollient creams?
- Aveeno cream
- Cetraben
- Diprobase
- E45
- Epaderm
- Oilatum cream
Give examples of thick of emollient creams?
- 50% Liquid paraffin
- Cetraben
- Diprobase
- Epaderm
- Hydromol
Discuss the Steroid Ladder?
- Mild: Hydrocortisone 0.5%-2.5%
- Moderate: Eumovate and Betnovate RD
- Potent: Betnovate and Cutivate
- Very potent: Dermovate
What is the “finger-tip” rule?
- 1 finger tip unit (FTU) = 0.5 g, skin area about twice that of the flat of an adult hand
- What is the most common opportunistic bacterial infection microbe for eczema?
- Staphylococcus aureus
What is the management for a Bacterial infection of Eczema?
- Flucloxacillin
What is Eczema Herpeticum
- A severe primary infection of the skin by HSV1, HSV2 or VZV
What is the presentation of Eczema Herpeticum?
What is seen on examination of Eczema Herpeticum?
- What is the management of Eczema Herpeticum?
- Presents as a rapidly progressive, widespread, vesicular, painful rash
- Systemic symptoms of fever, irritability, lethargy, reduced oral intake, lymphadenopathy
- O/E → Monomorphic punched-out erosions (circular, depressed, ulcerated lesions) usually 1–3 mm in diameter are typically seen
- Mild-Moderate → Oral Acyclovir
- Severe → IV Acyclovir
What is Psoriasis? What is the pathophysiology?
- Psoriasis is a chronic autoimmune condition which causes psoriatic skin lesions. It is caused by rapid turnover of new cells, causing abnormal build-up and skin thickening
Describe what Psoriatic skin may appear like?
Where can they be found?
- Dry, flaky, scaly, faintly erythematous skin lesions which appear in raised, roughened plaques
Commonly over the extensor surfaces of elbows, knees, scalp
State the subtypes / associations of Psoriasis?
Painful Pink Psoriasis -> Germy Itch Episodes
- Plaque Psoriasis
- Pustular Psoriasis
- Psoriatic Arthritis
- Guttural Psoriasis
- Inverse / Flexural Psoriasis
- Erythrodermic Psoriasis