LAUSR

A 1-year-old boy presented to the pediatric outpatient clinic with a 2 week history of gradually enlarging impetigo-like nodules on his bilateral cheeks (Fig. 1). He was born with severe asphyxia and had Apgar scores of 1 and 1 at 1 and 5 min, respectively. Thereafter, he developed hypoxic–ischemic encephalopathy. He had severe epilepsy that was controlled with several anti-epileptic drugs, including potassium bromide, which was started 5 months before the onset of the rash. Upon examination, he was afebrile, well-appearing, and had no rash other than that on his cheeks. Laboratory tests indicated no inflammatory changes. Bacterial and fungal cultures of the lesions yielded no growth. Skin biopsy showed non-specific diffuse infiltration in the dermis by inflammatory cells (Fig. 2, Hematoxylin-Eosin Stain). Bromoderma, a cutaneous adverse reaction to potassium bromide, was suspected. After discontinuation of potassium bromide, the facial lesions gradually improved (Fig. 3). Bromide was widely used as an anti-epileptic drug in the late 19th and early 20th centuries. Bromide use decreased after more effective and less toxic drugs, such as phenobarbital, were introduced; but the use of bromides has been increasing for cases of severe and refractory epilepsy that are not controllable with other anti-epileptic drugs. Bromide causes skin rashes in 25–30% of patients and is more common in younger patients. Bromoderma involves lesion types such as pastoral, acneiform eruptions, and granulomatous vegetating nodules. The half-life of the bromide ion ranges from 10.5 to 14 days. Therefore, serum bromide concentration can easily reach toxic levels and be eliminated gradually after cessation of the drug. The present cutaneous lesions improved slowly after drug withdrawal without apparent sequelae, including pigmentation. This rare but significant adverse effect should be considered when prescribing bromide. This case report was approved by the institutional review board of Yodogawa Christian Hospital (No. 2018-056). Written informed consent was obtained from the patient’s mother.