Diffuse erythematous rash in a healthy, afebrile infant

You are called to the emergency department to evaluate a healthy 9-day-old girl with erosions near her eyes, nose, and skin creases on the arm. She also has a positive Nikolsky sign (Figures A, B). The newborn is crying and uncomfortable, but is still feeding well. Upon examination, she is red from head to toe and has widespread erosions and crusting. The patient is afebrile with clear mucous membranes.

Figure A

Figure B

Diagnosis: Staphylococcal scaled skin syndrome (SSSS)

Differential diagnosisfor diffuse erythema
 with erosions

Given these clinical skin findings, initial differential diagnoses include Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and bullous impetigo. A history of drug intake or viral infection typically precedes SJS/TEN.¹ Additionally, SJS/TEN involves the mucous membranes of the conjunctiva, mouth, trachea, esophagus, anus, and genitalia.¹ Bullous impetigo is characterized by small superficial blistering lesions with expanding crusts that are localized to the areas of skin infection.¹

Pemphigus foliaceus (PF) is rare in children but presents with similar superficial blisters as seen in staphylococcal scalded skin syndrome (SSSS). The adhesion molecule desmoglein-1 in the superficial epidermis is the target of both the autoantibodies in PF and SSSS toxins.² PF can be confirmed with an immunochemical study to detect the presence of skin autoantibodies.²

A hot water burn is another differential to be considered given the reddening, blistering, and sloughing of the skin.

Discussion

SSSS is a reportedly rare, but likely more common than described, exfoliative disease of the skin mediated by epidermolytic toxins A and B produced by Staphylococcus aureus.¹ The disease predominantly occurs in neonates of 3 to 15 days of age, children aged younger than 5 years, and adults with various comorbidities.¹ Children are at greater risk due to their immature renal system and lack of immunity.³ In young children, the lack of prior exposure to SSSS-produced toxins triggers the development of anti- bodies to the causative agents, which protects against recurrence of SSSS in healthy patients. However, on first exposure, the toxins bind to and disrupt the adhesion molecule desmoglein-1 that is present in keratinized skin, but not in the mucous membranes. Be- tween 2010 and 2014, SSSS incidence increased 81% among infants younger than 1 year.⁴

Key clinical features of SSSS include a brief prodromal phase where there may be fever and/or irritability, followed by diffuse erythema with superficial blistering and crusting that tends to be most prominent in areas of skin rubbing, such as the mucocutaneous junction and skin creases. Skin appears reddish and scalded after blisters rupture, and the Nikolsky sign (the easy separation of skin layers upon horizontal pressure to the skin) is present.¹ Diagnosis of SSSS can be reached clinically and confirmed with bacterial culture. If in doubt, SSSS can be confirmed via skin biopsy, which shows superficial subgranular intraepidermal cleavage without necrosis.¹

Management

Treatment of SSSS consists of antistaphylococcal antibiotics, temperature regulation, maintaining fluid and electrolyte balance, and skin care. SSSS-associated strains of S aureus are usually methicillin-sensitive, so penicillinase-resistant beta-lactams, or cephalosporins, are favored for empiric management of SSSS.⁴ Vancomycin can be considered if a patient fails to improve following several days of treatment and methicillin-resistant strains of S aureus (MRSA) is suspected.¹

Clindamycin, a ribosomal inhibitor, is often recommended as a first-line agent to decrease SSSS toxin production, but up to 50% or more of triggering organisms may be resistant to clindamycin, and toxin binding may already be maximized at the time of diagnosis.⁴

Thick moisturizers are important to protect the skin and decrease pain.¹ In particular, moisturizers for the lips, which usually become crusty and painful, are essential to help with continued feeding in infants as their oral cavity remains unaffected by SSSS.

There is not an identifiable primary infection in many children with SSSS, but colonization can be demonstrated by obtaining bacterial cultures from sites of colonization, such as the medial canthi, nasopharynx, moist umbilical cord, and diaper area.

Patient outcome

The patient was diagnosed with SSSS and treated with parenteral ceftriaxone and clindamycin. Bacterial cultures from her nares grew MRSA and the clindamycin was discontinued. The rash improved dramatically over the subsequent 36 hours followed by diffuse desquamation. The patient was discharged from the ICU 2 days later, on oral cephalexin.

References

1. Meshram GG, Kaur N, Hura KS. Staphylococcal scalded skin syndrome: A pediatric dermatology case report. SAGE Open Med Case Rep. 2018;6:2050313X17750890. doi:10.1177/2050313X17750890

2. Lepe K, Yarrarapu SNS, Zito PM. Pemphigus foliaceus. StatPearls; 2021. Accessed August 5, 2021. https://www.ncbi.nlm.nih.gov/books/NBK499829/

3. Ross A, Shoff HW. Staphylococcal scalded skin syndrome. StatPearls; 2020. Accessed August 5, 2021. https://www.ncbi.nlm.nih.gov/books/NBK448135/

4. Wang Z, Feig JL, Mannschreck DB, Cohen BA. Antibiotic sensitivity and clinical outcomes in staphylococcal scalded skin syndrome. Pediatr Dermatol. 2020;37(1):222-223. doi:10.1111/pde.14014