Differential Diagnosis of Pediatric Sandpaper Rash

Life-Threatening Conditions to Rule Out First

The American Academy of Pediatrics recommends immediate doxycycline administration for children presenting with petechial or purpuric elements on a sandpaper-like rash, as mortality increases from 0% when treated by day 5 to 33-50% when delayed to days 6-9, regardless of age 1, 2
Palm and sole involvement is pathognomonic for Rocky Mountain Spotted Fever and requires urgent action, according to the Centers for Disease Control and Prevention 1, 2
The presence of thrombocytopenia, elevated hepatic transaminases, and hyponatremia supports the diagnosis of Rocky Mountain Spotted Fever, as stated by the Infectious Diseases Society of America 1, 2
Up to 40% of patients with Rocky Mountain Spotted Fever report no tick bite history, highlighting the importance of considering this diagnosis even in the absence of a reported tick bite, according to the Centers for Disease Control and Prevention 2

The American Academy of Pediatrics recommends throat culture or rapid strep test for diagnosis of scarlet fever, and if red flags are present, CBC with differential, CRP, comprehensive metabolic panel, and blood culture before antibiotics, as stated by the American Academy of Pediatrics 1, 2

Atopic dermatitis is a chronic, relapsing inflammatory condition with itchy skin and scratching behavior, requiring three of the following: history of itchiness in skin creases, history of asthma/hay fever in first-degree relatives, general dry skin, visible flexural eczema, or onset in the first two years of life, according to the British Medical Journal 4, 5
Deterioration in stable eczema suggests secondary bacterial infection or contact dermatitis, and Staphylococcus aureus infection commonly complicates eczema, as stated by the British Medical Journal 4, 5

The American Academy of Pediatrics recommends starting doxycycline immediately, even in children under 8 years, if petechiae/purpura, palm/sole involvement, or systemic toxicity are present, and obtaining blood cultures and hospitalizing urgently, as stated by the American Academy of Pediatrics 1, 2
Schedule follow-up within 24 hours for any child sent home, as serious infections are frequently missed at first presentation, according to the British Medical Journal 3, 1

Never dismiss a sandpaper rash without considering scarlet fever and Rocky Mountain Spotted Fever, as stated by the American Academy of Pediatrics 1
Do not delay doxycycline if Rocky Mountain Spotted Fever is suspected, as each day of delay dramatically increases mortality, according to the Centers for Disease Control and Prevention 1, 2
Absence of tick bite history does not exclude Rocky Mountain Spotted Fever, highlighting the importance of considering this diagnosis even in the absence of a reported tick bite, as stated by the Centers for Disease Control and Prevention 2
Deteriorating eczema requires evaluation for secondary infection, not just increased steroids, according to the British Medical Journal 4, 5