2-year-old girl presents with chronic diaper rash
A 2-year-old girl with a history of maple syrup urine disease presented to the dermatology clinic with an ongoing diaper rash.
The rash was present for 6 months and would wax and wane. Redness and erosions were persistent. She was noted to have chronic diarrhea with frequent loose stools and poor growth. She also had periods where she was very fussy.
The family used hypoallergenic baby wipes during diaper changes and made sure to change the diapers frequently. They tried hydrocortisone 1% cream without success. Physical exam revealed well-demarcated erythematous plaques with scaling and erosions on the buttocks and groin (Figure 1).
Can you spot the rash?
A. Irritant contact dermatitis
C. Acrodermatitis enteropathica/dysmetabolica
D. Allergic contact dermatitis
Acrodermatitis enteropathica (AE) — correct choice, C — is a rare cutaneous eruption caused by zinc deficiency and can be either inherited or acquired. The inherited form is due to a mutation in an intestinal zinc transporter, whereas the acquired form is usually from inadequate zinc secretion in breast milk, malnutrition or malabsorption disorders such as cystic fibrosis or celiac disease. Zinc is a cofactor for many enzymes and is essential for cell proliferation and immune defense.
AE typically presents in infancy, often when weaning from breast milk in the inherited form. The characteristic triad consists of a periorificial and diaper rash, alopecia and diarrhea. The rash is seen on the scalp, face (around the mouth, nose and eyes), ears and acral surfaces, such as the hands and feet. Involvement of the diaper area is almost always present. It commonly presents with sharply demarcated, erythematous, scaly plaques and can therefore mimic psoriasis. However, unlike psoriasis, lesions in AE often also have vesicles, bullae, and/or erosions. Failure to thrive, irritability and neurological disturbance and recurrent infections are other potential associated findings.
AE-like eruptions can also be seen in various metabolic disorders including biotin deficiency, organic acidemias (such as methylmalonic acidemia, propionic acidemia, maple syrup urine disease), urea cycle defects (citrullinemia) and phenylketonuria. This AE-like presentation unrelated to zinc deficiency has thus been coined acrodermatitis dysmetabolica (AD). This patient had a known history of maple syrup urine disease.
The differential diagnosis of a diaper rash is broad. Most commonly, diaper dermatitis is secondary to friction, irritation from contact with stool and urine and/or candidiasis. Given that a diaper rash is often a prominent finding in both AE and AD, these entities should be considered in the differential diagnosis of diaper dermatitis, especially when associated with poor growth, chronic diarrhea, irritability or not responding to conventional therapy for more common etiologies. The presence of a psoriasiform rash in the diaper area should prompt the practitioner to inquire about feeding, growth and gastrointestinal disturbance.
The diagnosis of AE is usually based on clinical presentation and is confirmed by measurement of low serum zinc levels. Alkaline phosphatase, a zinc-dependent enzyme, also may be low. If these levels are normal and another metabolic disorder is suspected, it may be helpful to consult with endocrinology/metabolism to assist in further workup for measurement of amino acids, organic acids, and other metabolites.
In AE, treatment with zinc supplementation results in rapid improvement of the rash and associated symptoms. Similarly, dietary modifications based upon the underlying disorder cause dramatic improvement in AD. This patient’s chronic diarrhea and vomiting from her underlying disease likely hindered her ability to adhere to her dietary requirements, thereby causing her skin manifestations. Diaper care is essential to promote healing. Given that erosions are often present, these open areas are prone to superinfection, particularly with Candida albicans. Thus, it is important to treat with a topical antiyeast medication such as clotrimazole or mupirocin. A low- or mid-potency topical steroid used for a limited time can also help to decrease the underlying inflammation. Basic diaper care with frequent diaper changes and barrier therapy with either petrolatum or zinc oxide are also important.
- Chapter 24. Inborn errors of metabolism. In: Paller A, Mancini AJ, eds. Hurwitz Clinical Pediatric Dermatology: A Textbook of Skin Disorders of Childhood and Adolescence. 5th ed. Edinburgh: Elsevier; 2016: 557-572.
- PerafánRiveros C, et al. Pediatr Dermatol 2002;doi:10.1046/j.1525-1470.2002.00200.x.
- Tabanliolu D, et al. Pediatr Dermatol. 2009;doi:10.1111/j.1525-1470.2008.00803.x.
- For more information:
- Michele Khurana, MD, is a pediatric dermatology fellow at The Children’s Hospital of Philadelphia. She can be reached at email@example.com.
- Marissa J. Perman, MD, is an attending physician at The Children’s Hospital of Philadelphia.