Paeds RashesKawasaki disease

Epidemiology: infants and children affected; 85% <5yrs, 30% <1yr; peak occurrence 18-24/12; most common cause of acquired paediatric heart disease; incr in Asian / Blacks; 9-20:100,000Pathophysiology: Generalised systemic vasculitis of medium sized vessels (inc. coronary, renal, hepatic, splanchnic) of unknown cause (likely post-infectious, due to super Ag bacterial toxins)

Phases:Acute febrile phase: weeks 0 - 2; myocarditis (25%; resolves alone), pericarditis (resolves alone), pericardial effusion / arrhythmia (20%; rarely large), valvular dysfunction, LV dysfunction (50%), CCF (<5%; usually resolves by 6-8/52); MI (1%); conduction defects (20%); coronary arteritis begins

Diagnostic Criteria

1) Fever >5 days (abrupt onset; in 100%)2) 4 out of 5 of following: can have <4 if echo shows CAD; those <6m

old may have incomplete presentation (2-3 criteria); all the below occur within 3/7 of rash

a. Bilat non-exudative bulbar conjunctival injection (with perilimbic sparing) – present in 80%

b. Pharyngeal oedema / red cracked lips / strawberry tongue – present in 90%; lasts 2-3/52; dry, crack and fissure by 6/7

c. Cervical lymphadenopathy – present in 60-98%; usually solitary, unilateral, >1.5cm

d. Diffuse erythema and swelling of hands and feet during acute phase (predilection for perineum, usually accompanies onset of fever; erythema, oedema) periungal desquamation during convalescent phase (after 2-3/52); present in 85-95%

e. Polymorphous generalized rash – present in 99%

May also get arthritis (35%), hepatitis (40%), AP, D+V, urethritis is sterile pyuria (70%), asceptic meningitis (25%), gallbladder hydrops (<10%)

Subacute phase: weeks 2 - 3Convalescent phase: weeks 4 - 6

Symptoms: fever for 1-2/52; tachycardia out of proportion to fever, gallop rhythmIx: ECG: non-specific ST-T waves changes (in 7%) CXR Bloods (anaemia for age, decr alb, incr plt, incr WBC, incr ALT, incr ESR and CRP ++), ASOT / anti-DNAase B Urine (sterile pyuria) Echo (perform at initial presentation at 2/52 at 6/52 at 1yr; may not need to do initial echo if present <10/7 with normal ECG)Complications: Coronary artery aneurysms (20% untreated children) occur in 2nd – 4th week (can be as early as 3/7 or be delayed 6-8/52; RF for development: male, <1yr, >5yrs, fever >10/7, decr alb / Hb, clinical signs of cardiac involvement); stenosis, thrombosis; MI is leading cause of death; 75% fatalities occur within 6/52; children <6/12 at incr risk of developing cardiac complications so have lower threshold for diagnosis in this group; mortality <1%; excellent prognosis if trt within 10/7 and normal echoTreatment: Supportive careIVIG 2g/kg over 12hrs symptomatic improvement in 90%, prevents aneurysm in 95% (decr risk of heart abnormality from 20% to 3-5% if given in 1st 10/7); if ongoing fever, may require 2nd dose; aim to commence early than D5High dose aspirin 30-50mg/kg/day until fever gone 3-5mg/kg OD for 6-8/52 helps prevent thrombosis; no evidence that it prevents the formation of aneurysms; must continue on low dose therapy indefinitely if develop aneurysms, otherwise stop at 6/52Corticosteroids if refractory to above treatment

Scarlet Fever

Cause: Group A beta-haemolytic strep erythrogenic toxinIncubation: 2-4/7 (ie. Short)

Sx: Acute onset fever, sore throat, headache, V, AP exanthem develops over 1-2/7 Red tonsils and pharynx covered in exudates Tongue white coating through which red hyptertrophied papillae project (white strawberry tongue) White coating disappears after 4-5/7 red strawberry tongue Bright red / haemorrhagic spots on soft palate After 12-48hrs Red, finely punctate 1-2mm blanching papules (rough sandpaper) on neck, axillae and groin Rapidly spreads to trunk and extremities Linear petechial eruptions in antecubital and axillary folds (Pastia’s lines) Facial flushing and circumoral pallor Fades at 6/7 Desquamates at 2/52, on hands and feet 1st

Complications: OM, sinusitis, rheumatic fever, post-strep GNIx: ASOT, swabTrt: Penicillin 10/7

Measles

Complications: OM (2.5%), pneumonia (4%; responsible for 50% deaths); encephalitis (0.1%; onset 1-2/52 after disease; mortality 10-15%; permanent neuro damage in 40%); subacute sclerosing panencephalitis (can occur 4-10yrs later, progressive mental deterioration and death); myocarditis, nephritis, hepatitis, pericarditis, keratitisIx: swab for PCR (will be +ive within few days, when serology may still be negative; also useful in immunocomp); blood for serology (IgM = infection, levels peak at 7-10/7; IgG = immunity; may be negative if <4/7 from onset fever, need to do rpt after 1/52, remains +ive for 3/12, sens 100%, spec 98%); double bag specs and don’t send through lamsenTrt: Supportive; need infection control measures; notifiable disease; no school / child care for 5/7; admit if: poor PO intake, resp compromise, CNS complications

Prophylaxis:Exposed if: enter same room within 2hrs of infected person leavingNon-immune if: not had 2x MMR and born after 1969, from 6/12 to 1st vaccine, if >4yrs and not had 2nd vaccine, pregnant, immunocomp, or prem <28/40Offer MMR if <72hrs (not if pregnant); if immunocomp / pregnant / >72hrs, consider Ig

HSP Epidemiology: 2:1000; more Asian / Indian; usually 4-6yrs (2-11yrs)Cause: Allergic vasculitis, follows URTI, IgA mediated; assoc with infection, drugs, vaccines; may be post Grp A strepPathology: Small vessels (skin, GIT, kidneys, jts)

Cause: RNA myxovirusEpidemiology: rare in immunised; now mostly seen in older patients; highly infectious (90% susceptible close contacts will become infectedIncubation: 7-18/7 (av 10/7); 14/7 between exposure and rash; patient infectious from 5/7 before rash to 4/7 after rash

Case definition: 3-4/7 URTI rash 1. Fever >38 (ie. High)2. Rash : fever always present at time of onset of rash; behind ears

and at hairline spreads from head to feet, inc palms and soles; erythematous maculopapular, red blanching confluence esp on face copper-brownish hue as resolves desquamates after 3/7; lasts 1/52

3. 1 of cough / coryza / conjunctivitis / Koplick spots (white, bluish- white 1mm spots with red base on buccal mucosa; appear 1/7 before rash); may have generalised lymphadenopathy; may be diarrhoea

Trt: Usually resolves in 3-4/52; supportive; monitor BP and urine for 6/12; IVF if ill; NSAIDS; Consider prednisone 1mg/kg for 2/52 (if abdo, jt or scrotal disease; may prevent renal complications (2% get long term renal impairment); helps jt pain, abdo pain, oedema)Admit if: Abdo, renal complications; symptomatic relief

Notes from: Dunn, Starship Guidelines

Paeds RashesHow to Describe a Rash

Palpable lesionsPapules <0.5cmNodules >0.5cmVesicles<0.5cm, clear fluidPustules Yellow fluidPurpuraPurple; palpable / non-palpable

Non-palpable lesionsMacules Alterations in circumscribed area of skinPigmentation

Assessment

Sx: Palpable purpura on buttocks and legs (extensor surface) – presenting Sx in 50%; maybe also erythematous, urticarial, echymoses, petechaie AP (+N+V+D; in 60-80%; diffuse and colicky; occurs after rash; 50% have blood in stool; 5% get acute GI haemorrhage; 3% get intussusception) Migratory polyarthralgia (66-80%; presenting Sx in 25%; usually resolves after 24-48hrs; in gravity dependent jts) Renal failure (in 20-50%) – nephritic syndrome Generalized oedema (eg. Feet; often painful)Ix: Haematuria and proteinuria in 90%; urine, FBC (plts normal), U+EComplications: Nephritic / nephrotic syndrome, ARF (<1%), HTN; if proteinuria = more severe and needs FU; Intussusception (5%); bowel perf

History Fever, systemic symptoms, prev immunizations, human/animal contacts, travel, bites/stings, drugs, food, environmental exposureInitial location of rash, pattern and timeframe of development, initial Morphology

Examination VitalsUndress – scalp, ears, neck, MM, skinfolds, digits, web interspaces, palms, solesMorphology, location, distribution

ENTEROVIRUSES

Echovirus 9, Coxsackievirus A9Transmission Fecal-oral, oral-oral, RS-oralSx Non-specific febrile illnesses, RTI, GI Sx, meningitis; variety of rashes

Maculopapular rash beginning on face and neck, extending to trunk and feet; may be lesions on buccal mucosa and soft palate (resemble Koplik spots); maybe petechiae, vesicles, urticaria

Duration 5/7

Enterovirus (hand, foot and mouth disease)Sx Fever, anorexia, malaise, sore mouth 1-2/7 later, oral lesions

then cutaneous lesionsOral lesions: painful 4-8mm vesicles on erythematous base on buccal mucosa, tongue, soft palate, gingiva ulcerateCutaneous lesions: 3-7mm red papules grey vesicles on palms and soles (may be dorsum of feet and buttocks) heal in 7-10/7

Trt Hydration, analgesia, mouthwash

Coxsackievirus (herpangina)Sx Fever, mouth pain, oral ulcers

Similar ulcers to hand, foot and mouth; but no skin lesions

RUBELLA

Incubation 12-25/7Sx 1-5/7 fever, malaise, headache, sore throat irregular pink macules

and papules on face, spreading to neck, trunk and arms; coalesces then clearsForchheimer spots: pinpoint petechiae on soft palate that coalesceSuboccipital and posterior auricular lymphadenopathy

Trt Supportive

ERYTHEMA INFECTIOSUM (FIFTH DISEASE, SLAPPED CHEEK)

Sx Abrupt appearance of rash fiery red rash on cheeks; diffuse erythema of closely grouped tiny papules on erythematous base; edges slightly raised; circumoral pallor; sparing of eyelids and chin; lasts 4-5/71-2/7 after face rash nonpruritic macular/maculopapular erythema on trunk and upper limbs spreads; lasts 1/52; spares palms and soles; fades with central clearingAssoc with fever, malaise, headache, sore throat, cough, coryza,

N+V+D, myalgiaTrt Supportive

HERPES

Transmission HSV-2 genital, HSV-1 oralSx Herpes labialis, gingivostomatitis – painful umbilicated vesicles

unroof and crust overEczema herpiticum – break out on area previously affected by eczemaHerpetic whitlow – distal fingers

Trt Consider sexual abuseOral acyclovir; supportive

CHICKENPOX

Sx Pruritic generalized vesicular exanthem with mild systemic symptoms; starts on trunk / scalp as faint red macules vesicular in 24hrs, on erythematous base dry and crust; widespread, palms and soles spared; may occur on MM

Trt Supportive if uncomplicated; cleanse lesions to prevent 2Y infection; antivirals only if immunocompromisedIf neonate exposed: nil trt, present if develops chickenpox then trt with IV aciclovir

ROSEOLA INFANTUM (SIXTH DISEASE)

Sx Abrupt onset fever lasting 3-5/7, cough, coryza, anorexia, abdo discomfort fever settles appearance of rash over 1-2/7. Erythematous,

blanching, macular/maculopapular eruption, discrete rose / pale pink 2-5mm lesions; most on neck, trunk and buttocks; can also involve face and arms. No MM involvement. Lasts 1-2/7 fades rapidly.

Trt Supportive

IMPETIGO

Cause Staph aureus, beta-haemolytic strepSx Lesions on face, neck, and extremities; usually no systemic Sx

Nonbullous: small erythematous macules and papules thin walled vesicles pustules rupture golden yellow crust smooth red surface underneath; may become confluent; local adenopathyBullous: local; toxin causes separation of skin and bullae; thin walled

bullae 0.5-3cm, filled with clear-yellow fluid, rupture easilyStaph scalded skin syndrome: systemic; malaise, fever, irritability, tender skin; extensive areas of exfoliation; Nikolsky sign +ive

Trt Nonbullous: topical; oral only if severeSSSS: inpatient, IVABx; may require admission to burns unit

ERYSIPELASCause Group A beta-haemolytic strepSx Fever, chills, malaise, vomiting

Local redness, heat, swelling; raised indurated border; well demarcatedTrt Penicillin / erythromycin

SCABIES

Sx Severe pruritis; generalized eruption of linear burrows, papules, pustules, vesicles; mostly affect hand, feet, groin; excoriation from scratching

Trt Permethrin

ERYTHEMA TOXICUM

Sx Erythematous macules 2-3cm on face, trunk, extremities; central 1- 3mm pustules

Trt None

SEBORRHOEIC DERMATITIS

Sx Greasy yellow/red scales, mostly on scalp; not pruriticTrt Mineral oil

NAPPY RASH

Contact dermatitis: erythematous macular/papular with well demarcated borders; trt with hygeineCandidal dermatitis: erythematous papular / pustular lesions; scaling around margins; satellite lesions