Infant’s Rash Defies Most Likely Diagnoses

TOPLINE:

Clinicians should consider zinc deficiency in premature infants having an erythematous, scaly, sharply demarcated rash that does not respond to treatments for the most likely diagnoses.

METHODOLOGY:

• Investigators report the case of a 5-month-old infant born prematurely, at 26 weeks of gestation, brought to the emergency department with a rash.
• The rash consisted of erythematous, scaly, crusted skin lesions of the head, neck, and perineal and genital areas; other symptoms included irritability and diarrhoea.
• The initial differential diagnosis included eczema, allergy, and infection.

TAKEAWAY:

• The infant’s history was noteworthy for exclusive breastfeeding, chronic lung disease of prematurity, recent bronchiolitis, and psoriasis in a paternal aunt.
• The rash was non-responsive to systemic antibiotics (for suspected superinfected eczema), exclusion of dairy from the mother’s diet (cow’s milk protein allergy), topical emollients and steroids (eczema), topical miconazole and oral nystatin (fungal infection), oral aciclovir (viral infection), and repeated oral co-amoxiclav (impetigo and cellulitis).
• The infant was receiving prophylactic iron and multivitamins, phosphate supplements, and alginic acid.
• Results of cultures, skin swabs, and bloodwork were normal/negative, except for mild thrombophilia and a low alkaline phosphatase level.
• The infant was started on zinc supplements based on clinical suspicion of deficiency, resulting in rapid resolution of symptoms, including near-complete resolution of the rash within 1 week.
• When results for a pre-supplementation zinc level became available, they showed a value of 1.8 μmol/L (normal range, 5-21.5 μmol/L); the level after 1 week of supplementation was 11 μmol/L.

IN PRACTICE:

“Consider nutritional zinc deficiency in a premature infant presenting with an erythematous scaly, well demarcated circumoral, anogenital, and acral skin changes unresponsive to treatments of common differential diagnoses. Risk factors…include prematurity [and] exclusive breastfeeding especially with a deficient or restrictive maternal diet,” the authors wrote. “Start zinc supplementation before confirmation with a low zinc level as test results can take time. In children unable to maintain zinc levels after stopping supplements, genetic testing for primary acrodermatitis enteropathica should be considered,” they concluded.

SOURCE:

The case report was led by Amy Smit, Gateshead Health NHS Foundation Trust, Gateshead, UK, and was published online in BMJ.

DISCLOSURES:

The case report did not receive any funding. The authors reported no conflicts of interest.