Pediatric Rashes

Question 0

Vesicular rash Common causes of vesicular rash are:?

Answer 0

Vesicular rash Common causes of vesicular rash are:
• *Chickenpox: successive crops of papulovesicles on an erythematous base; the vesicles become encrusted. Lesions present at different stages. The mucous membranes are involved.
• *Eczema herpeticum: exacerbation of eczema with vesicular spots caused by a herpes infection

Question 1

What is the differential diagnosis of a maculopapular rash and children?

Answer 1

Maculopapular rash This is most likely to be caused by a viral exanthem but might be a drug-induced eruption. Common diagnostic features are: • *Measles: prodrome of fever, coryza and cough. Just before the rash appears, Koplik’s spots appear in the mouth. The rash tends to coalesce. • *Rubella: discrete, pink macular rash starting on the scalp and face. Occipital and cervical lymphadenopathy might precede the rash. • *Roseola infantum: occurs in infants under 3 years. After 3 days of sustained fever, a pink morbilliform (measles-like) eruption appears as the temperature subsides. It is caused by human herpesvirus (HHV)-6 or HHV-7. • *Enteroviral infection: causes a generalized, pleomorphic rash and produces a mild fever. • *Infectious Mononuclosis: symptoms include malaise, fever and exudative tonsillitis. Lymphadenopathy and splenomegaly are commonly found. • *Kawasaki disease: causes a protracted fever, generalized rash, red lips, lymphadenopathy and conjunctival inflammation. • *Scarlet fever: causes fever and sore throat. The rash starts on the face and can include a ‘strawberry’ tongue

Question 2

What is the differential diagnosis of hemorrhagic rash?
Haemorrhagic rash Due to extravasated blood these lesions do not blanch on pressure. Lesions are classified by size: • Petechiae (smallest). • Purpura. • Ecchymoses (largest)

Answer 2

Common diagnostic features are:
• *Meningococcal septicaemia: petechial or purpuric rash (might be preceded by maculopapular rash).
• *Acute leukaemia: look for pallor and hepatosplenomegaly.
• *Idiopathic thrombocytopenic purpura: the child looks well but might have petechial rash with, or without, nose bleeds.
• *Henoch–Schönlein purpura: distribution is usually on the legs and buttocks. Arthralgia and abdominal pain might be present.
• *Bleeding disorders: haemophilia, von Willebrand disease and Ehlers–Danlos usually present with easy bruising and prolonged bleeding following trivial trauma
** consider child abuse

Question 3

What is the differential diagnosis of an urticarial rash?

Answer 3

Causes include:
• Food allergy, e.g. shellfish, eggs, cows’ milk.
• Drug allergy, e.g. penicillin: note that < 10% of penicillin allergies are substantiated.
• Infections, e.g. *viral: this is the most common and is often self-limiting.
• Contact allergy, e.g. plants, grasses, animal hair

Question 4

What rash has target lesions and what is the etiology?

Answer 4

Erythema multiforme:
A distinctive, symmetrical rash characterized by annular target (iris) lesions and various other lesions including macules, papules and bullae. The severe form with mucous membrane involvement is Stevens–Johnson syndrome. Causes include infections (most commonly herpes simplex, mycoplasma or Epstein–Barr virus) and drugs. Mostly it is idiopathic and self-limiting

Question 5

Symptoms include perianal rash, itching and rectal pain; blood-streaked stools may also be seen in one third of patients. It primarily occurs in children between six months and 10 years of age and is often misdiagnosed and treated inappropriately. Bright red rash, sharply demarcated

Answer 5

Perianal streptococcal dermatitis

-often misdiagnosed and treated inappropriately. A rapid streptococcal test of suspicious areas can confirm the diagnosis.
Signs and symptoms in this study included perianal dermatitis (90 percent), perianal itching (78 percent), rectal pain (52 percent) and blood-streaked stools (35 percent).4 Intrafamily spread was reported in 50 percent of possible cases. Communal bathing is thought to facilitate familial spread; however, the incidence of communal bathing did not reach statistical significance in this study.

• Subcutaneous involvement suggestive of cellulitis is normally absent. The absence of fever and systemic signs and symptoms also supports the superficial localization of this rash.4 Spread to the penis or vulva may occur6 (Figure 1). Fissures, a mucoid discharge and yellow crusting are sometimes present.
• Relapses have been noted in up to 39 percent of cases; thus, close follow-up is indicated.4 Repeat treatment is usually successful.

Treatment consists of amoxicillin, 40 mg per kg per day, divided into three doses, and/or topical applications of mupirocin (Bactroban) 2 percent three times per day for 10 days.3,7 Penicillin, clindamycin phosphate (Cleocin Phosphate) and erythromycin have also been used

Question 6

Describe the presentation of Erythema Infectiosum(Fifth Disease)

Answer 6

> Caused by parvovirus B 19: 3 phases
prodrome of headache, low fever, rhinorrhea for several days followed by:
a macular diffuse erythema of cheeks with circum-oral pallor (slapped cheeks)
one to 4 days later a lacy reticulated rash consisting of discrete erythematous macules and papules on proximal extremities&raquo_space;the trunk becomes involved later