Infection and Rashes

Question 1

Define Macule

Answer 1

flat lesion ,usually a circumscribed change of colour

Question 2

Define Papule

Answer 2

small , solid, elevated lesion

Question 3

Define Nodule

Answer 3

a large , solid , palpable and elevated lesion

Question 4

Define Plaque

Answer 4

Plaque – a lesion slightly raised over a larger area

Question 5

Define Blister

Answer 5

Blister – an elevated lesion ,fluid filled

lesions

Question 6

Define Ulcer

Answer 6

Ulcer – depressed lesion with loss of surface epithelium

Question 7

Define Atrophy

Answer 7

Atrophy – a depressed lesion with intact surface epithelium

Question 8

Define Crust

Answer 8

Crust – a mixture of scale and serum – yellowish accretions on the surface of a lesion

Question 9

Define Petechiae

Answer 9

Petechiae – non raised red-brown non blanchable

Question 10

Chicken pox virus

Answer 10

Varicella Zosta Virus

Question 11

Stages of chicken pox

Answer 11

Virus enters upper respiratory tract
Day 4-6: Viraemia
Incubation period 10-14 days can be longer
First symptom pyrexia for up to 4 days
Headache, malaise, abdo pain
Crops of vesicles over 3-5 days on head neck and trunk (sparse on limbs)
Papule to Vesicle to Pustule to Crust

Question 12

Management of chicken pox

Answer 12

analgesia – paracetamol for discomfort and pyrexia.
pruritis – antihistamine or calamine lotion
acyclovir only for those at risk of complications or immunocompromised.

Question 13

Impetigo

Answer 13

Very common superficial, contagious, blistering bacterial infection

Question 14

Types of impetigo

Answer 14

Non Bullous: Group A beta haemolytic strep pyogenes

Bullous: Fluid lesions (Staph. Aureus)

Question 15

Presentation of non bullous impetigo

Answer 15

More common 70%
Usually aymptomatic. Occasionally pruritic
Tiny pustules or vesicles that evolve to honey coloured crusted plaques <2cm.
On face. Can be at extremeties where bites , abrasions, lacerations, burns, scratches or trauma could have occurred. Regional lymph nodes enlarged
Little or no surrounding erythema

Question 16

Presentation of bullous impetigo

Answer 16

Occasionally pruritic. Can be painful
Usually on the face, trunk, extremities, buttocks, or perineal regions.
More common in neonates
Thin roofs and tend to rupture spontaneously

Question 17

Diagnosis of impetigo

Answer 17

Clinical diagnosis if severe take swabs if:
?MRSA
It is severe or extensive
Recurrent or treatment is failing

Question 18

Management of impetigo

Answer 18

Neonates: Abx, Erythromycin PO or Vancomycin IV (MRSA +)
Treatment superficial/limited: mupirocin, fusidic acid
Widespread cut. lesions: Oral Abx such as dicloxacillin or flucloxacillin, erythromycin
Deep tissue/systemic infection: Parenteral antibiotic therapy with nafcillin, oxacillin, or clindamycin

Question 19

Erythema Multiforme

Answer 19

Hypersensitivity reaction resulting in papules forming over back of hands and feet spreading to trunk. Often involving the face. Papules then evolve to plaques and then typical target shaped lesions

Lesions have dusky red centre pale around it and then dusky red ring

Commonly associated with stevens johnson syndrome

Question 20

Common infections associated with Erythema Multiforme

Answer 20

Herpes Simplex Virus
Mycoplasma Pneumoniae

Can also be:
Hep B, Epstein Barr virus, Cytomegalovirus and more (see BMJ)

Question 21

Drugs associated with erythema multiforme

Answer 21

most commonly associated-Allopurinol

Recent drugs- Nevirapine, lamotrigine, sertraline, pantoprazole, tramadol
Antibiotics- Sulphonamides, including co-trimoxazole, penicillin cephalosporins, fluoroquinolones, vancomycin
NSAIDs- Piroxicam, fenbufen, ibuprofen, ketoprofen, naproxen, tenoxicam, diclofenac, sulindac
Anti-TB- Rifampicin, ethambutol, isoniazid, pyrazinamide
Anticonvulsants- Barbiturates, carbamazepine, phenytoin, valproate, lamotrigine

Question 22

Classification of erythema multiforme

Answer 22

EM Minor: Typical targets or raised oedematous papules, with acral distribution, without involvement of mucosal sites and involving <10% total body surface area.
EM Major: Typical targets or raised oedematous papules, with acral distribution, with involvement of mucosal sites and involving <10% total body surface area.

Question 23

Management of erythema multiforme

Answer 23

Supportive care to maintain hydration and prevent erosions from developing secondary bacterial infection

Treatment of suspected precipitating infections

Suppression therapy with antivirals if recurrent disease is caused by herpes simplex virus (HSV)

Topical or systemic corticosteroids to reduce inflammation.

Question 24

Stevens Johnson Syndrome (SJS) and Toxic epidermal necrotitis (TEN)

Answer 24

More severe forms of eryrhema multiforme

SJS: <10% total body surface area (TBSA) involvement. Causes include Mycoplasma pneumoniae , viral infections, and vaccines, or drug-related.

TEN: >30% TBSA involvement. Drug-related

Question 25

Clinical impression of stevens johnson syndrome and toxic epidermal necrotitis

Answer 25

Blisters or macules and flat atypical target lesions diffuse erythema Nikolsky's sign (epidermal layer easily sloughs off when pressure is applied to the affected area) Mucosal involvement presents with erosions or ulceration of the eyes, lips, mouth, pharynx, oesophagus, GI tract, kidneys, liver, anus, genital area, or urethra One of the potential complications of SJS/TEN is mucosal involvement of the upper and lower respiratory tract, with vesicle formation, ulceration, and actual mucosal sloughing that may lead to laryngeal stridor, along with possible retractions and oedema of the nasopharynx

Question 26

Wallace Rule of 9

Answer 26

Splits body into 9 parts allows assessment of the total body surface area an infection may cover: Head and neck total for front and back: 9% Each upper limb total for front and back: 9% Thorax and abdomen front: 18% Thorax and abdomen back: 18% Perineum: 1% Each lower limb total for front and back: 18%.

Question 27

Management of SJS/TEN

Answer 27

``` ABG and Oxygen sats to assess for respiratoy distress Dressings with topical Abx Fluid management Analgaesia (avoid NSAIDs where possible) Opthalmic consultation ```

Question 28

Kawasaki disease

Answer 28

acute, febrile, self-limiting, systemic vasculitis of unknown origin that almost exclusively affects young children

Question 29

Presentation of Kawasaki disease

Answer 29

Fever lasting ≥5 days Marked irritability of the child Erythema, swelling and desquamation affecting the skin of the extremities Bilateral conjunctivitis Rash Inflammation of the lips, mouth and/or tongue Cervical lymphadenopathy

Question 30

Complications of kawasaki disease

Answer 30

development of an acute coronary artery vasculitis with dilatation or aneurysm formation. In addition, KD may lead to myocardial infarction, sudden death, and ischaemic heart disease.

Question 31

Stages of kawasaki disease

Answer 31

Acute febrile stage: 1-2 weeks Fever, irritability, cervical adenitis, conjunctivitis, rash, mucosal erythema, painful erythema of the hands and feet, arthralgia or arthritis, possible myocarditis, and pericarditis Subacute: weeks 2-4 Fever, rash, and lymphadenopathy have resolved. Persistent irritability, poor appetite, and conjunctival infection, desquamation of extremities begins at this stage. Patient may be completely asymptomatic if given intravenous immunoglobulin (IVIG) Cardiac abnormalities develop Convalescent weeks 4-8 All signs of inflammation have receded and acute phase markers normalise. If present, coronary artery ectasia or aneurysms may persist and enlarge. Chronic stage: If present, coronary artery dilation may resolve. However, coronary artery aneurysms may persist through to adulthood. Such patients are at risk of subsequent coronary artery thrombosis, rupture, and myocardial infarction.

Question 32

Management of Kawasaki disease

Answer 32

Intravenous Immune Globulin 2g/kg x1 Aspirin 80-100 mg/kg/day until fever settled for 14 day, then 3-5mg/kg/day x ≥ 6-8 weeks Consider corticosteroids and infliximab for second line management Also ensure Echocardiogram is carried out and cardiology follow up where necessary

Question 33

Scabies

Answer 33

Highly contagious pruritic rash caused by parasitic mite sarcoptes scabiei. Manifests as rash usually 4-6 weeks after infection.

Question 34

Clinical presentation of scabies

Answer 34

Widespread pruritus. Usually worse at night or when the person is warm. Skin lesions can be macules, papules, pustules or nodules. Lesions seen on the site of the burrows Burrows may be visible as fine, wavy, greyish, dark or silvery lines, 2-15 mm long, sometimes with a minute speck (the mite) at the closed end

Question 35

Key investigations for scabies diagnosis

Answer 35

Clinical | Ink burrow test

Question 36

Scabies management

Answer 36

Clothes, towels, and bed linen should be machine-washed (at 50°C or above) to prevent re-infestation and transmission. Items that cannot be washed can be kept in plastic bags for at least 72 hours to contain the mites until they die. -benzyl benzoate lotion ,apply for 24hours ,may be repeated in 1 week -permethrin cream Babies <2 months -5% sulphur ointment

Question 37

Measles

Answer 37

Highly infectious disease caused by measle virus (ssRNA Morbillivirus)

Question 38

Mode of transmission of measles

Answer 38

airborne via respiratory droplets.

Question 39

Measles symptoms

Answer 39

Prodrome - lasts 2-4 days with fever, runny nose, mild conjunctivitis and diarrhoea. Koplik spots are pathognomic and appear on the buccal mucosa opposite the second molar teeth as small, red spots each with a bluish-white speck (sometimes compared to a grain of rice) in the centre Rash-first seen on forehead and neck and spreads, involves trunk and finally limbs over 3-4 days. It may become confluent in some areas. Rash then fades after 3-4 days in the order of its appearance. It leaves behind a brownish discoloration sometimes accompanied by fine desquamation.

Question 40

Complications of measles

Answer 40

Neuro Acute demyelinating encephalitis Subacute sclerosing panencephalitis Measles inclusion body encephalitis Gastro- Diarrhoea Resp-Bronchopneumonia VitA def, and blindness Immunodeficiency

Question 41

Management of uncomplicated measles

Answer 41

paracetamol or ibuprofen and plenty of fluids. Patients should remain at home to limit disease spread. MMR is already part of childhood immunisations Post exposure prophylaxis of MMR vaccine to those who are susceptible (>6 months) ideally within the first 72 hours of exposure.

Question 42

Erythema infectiosum

Answer 42

AKA slapped cheek disease due to parvovirus B19

Question 43

Presentation of erythema infectiosum

Answer 43

Prodromal- week after infection. mild and may include headache, rhinitis, sore throat, low-grade fever and malaise. Symptom free 7-10 days followed by slapped cheek rash. disappears after 2-4 days. 1-4 days after the facial rash appears, an erythematous macular/morbilliform rash develops on the extremities, mainly on the extensor surfaces. Fades over the next 3-21 days

Question 44

types of napkin dermatitis

Answer 44

Contact: prolonged exposure to urine and faeces, friction mild erythematous ,glazed appearance Seborrhoeic dermatitis: Cradle cap in babies salmon coloured greasy lesions and a predilection for intertriginous areas Candidiasis: beefy red in colour with pin point pustulo-vesicular satellite lesion

Question 45

Management of napkin dermatitis

Answer 45

Frequent nappy changes barrier cream zinc and caster oil apply hydrocortisone 1% in aqueous cream bd if candidiasis suspected -10% steriod and nystatin 20% in zinc cream

Question 46

Molluscum contagiosum virus (MCV)

Answer 46

Skin infection as a result of MCV of the POX family . Spread by direct contact usually through sports and by sharing towels, baths and gymnasium equipment. MCV1 most common. MCV2 common in immunosuppressed.

Question 47

Presentation of Molluscum contagiosum

Answer 47

Firm, smooth, umbilicated papules, usually 2-5 mm in diameter Usually it is asymptomatic but there may be tenderness, pruritus and eczema around the lesions Usually on trunk an extremeties No fever or malaise

Question 48

Management of molluscum contagiosum

Answer 48

Tend to heal spontaneously within 6 months – 1 year - liquid nitrogen 2-3 weeks - express contents with sharp curette - benzoyl peroxide cream apply daily

Question 49

Eczema Tx

Answer 49

Emollient (Aveeno, E45) Topical corticosteroids (1% hydrocortisone) Occlusive bandages Antibiotic with hydrocortisone for mildly infected eczema

Question 50

Infantile seborrhoeic dermatitis

Answer 50

Cradle cap Mild case resolved by emollient Scales cleared with low concentration sulfur and salycilic acid

Question 51

Urticaria

Answer 51

Hives normally due to viral infection or allergen exposure

Question 52

Haemangioma

Answer 52

Collection of small blood vessels causing lump under skin at risk of ulcerating.

Question 53

Common paediatric haemangiomas

Answer 53

Strawberry naevus: appear in first month and grow till 3-15months before reducing no need for treatment but can use topical propanol to speed process Sturge-Webster syndrome: port wine stain facial lesions in distribution of trigeminal nerve. Can present with epilepsy, intellectual disability or contralateral hemiplagia

Question 54

Diabetes triad

Answer 54

Polydypsia Polyurea Weight loss

Question 55

Diagnosis of diabetes

Answer 55

Random glucose >11 | Fasted glucose >7

Question 56

Complications of diabetes

Answer 56

Hypoglycaemia | Diabetic ketoacidosis

Question 57

Hypoglycaemia symptoms

Answer 57

Hunger Tummy ache Sweating Feeling faint or dizzy

Question 58

Signs of diabetic ketoacidosis

Answer 58

``` Acetone breath Vomiting Dehydration Abdo pain Hyperventilation (kussmajl breathing) Hypovolaemic shock Drowsiness Coma and death ```

Question 59

Diabetic ketoacidosis ranges

Answer 59

``` Glucose >11.1 Ketones >3 U&E, creatinine (dehydration) Blood gas analysis (acidosis) T wave changes in hypokalaemia Weight loss Evidence of precipitating cause. ```

Question 60

DKA management

Answer 60

Fluids: 0.9 saline 40mmol KCl 12h, 5% glucose added when <14. After 12hr id plasma stable 0.45 saline 40 mimol KCl Insulin infusion 0.1 U/kg per Hr Potassium as will fall when infusion starts Avoid bicarbonate for acidosis should revolve with fluids Restablish oral fluids Identify cause

Question 61

Hand foot and mouth disease

Answer 61

Painful vesicular lesions on hands, feet, mouth and tongue occasionally buttocks

Question 62

Fifth disease

Answer 62

Human parovirus b19. Slapped cheek rash, progressing to trunk Aplastic crisis- in children with high red blood cell turnover or compromised immune system

Question 63

Erythema toxicum

Answer 63

Common benign condition in neonates usually between 2-5 days. More common in full term neonates. Combination of macule, papule and pustules.

Question 64

Hand foot and mouth disease

Answer 64

Coxsackievirus A16 virus and enterovirus 71

Question 65

Hand foot and mouth disease presentation

Answer 65

Prodrome : Low grade fever, malaise, loss of apettite. sore mouth cough abdo pain Hand foot and mouth lesions

Question 66

Hand foot and mouth Tx

Answer 66

Supportive. No treatment Refer if neurological symptoms occur (myoclonic jerk, severe headaches, or encephalitis - Symptoms tend to resolve within 10 days

Question 67

Glandular fever (infectious mononucleosis)

Answer 67

Epstein Bar virus

Question 68

IM presentation

Answer 68

``` Low grade fever Malase Sore throar Non pruritic rash Nausea Arthralgia ```