Prurigo pigmentosa post-bariatric surgery: a case report

Background

Prurigo pigmentosa (PP), also referred to as Nagashima disease, is an acquired dermatological condition that is characterized by pruritic erythematous eruptions including papules and plaques surrounded by a reticular pattern of hyperpigmentation. It was first described in 1971 when Japanese dermatologist Masaji Nagashima noticed similar dermatological manifestations among 8 patients of Asian descent. The disease has been strongly associated with ketosis and ketogenic diet; however, the underlying etiology is unknown. Effective treatment involves an oral antibiotic and a balanced diet. The disease classically affects young women of Asian descent, but cases affecting males and people of non-Asian ancestry have also been observed. We present an unusual case of PP in a Saudi male that started 18 days following bariatric surgery.

Case Description

The patient is a 25-year-old morbidly obese Saudi male who complained of an intensely pruritic rash 3 weeks after undergoing bariatric surgery. His past medical history is positive for irritable bowel syndrome (IBS). A punch skin biopsy yielded the diagnosis, and a combination treatment consisting of minocycline and a topical corticosteroid was prescribed. The patient presented again 2 weeks after the initial visit with complete resolution of the rash. He reported adherence to the medication regimen. Pruritus had resolved. Upon examination, post-inflammatory hyperpigmentation in a reticular pattern was observed over the trunk, upper abdomen, and chest. Hydroquinone 4% cream was prescribed to treat the post-inflammatory hyperpigmentation.

Conclusions

Nowadays, PP cases are being reported from all around the world, including cases of PP that appeared following bariatric surgery for weight loss without ketogenic dietary modification. Theoretically, the typical PP patient is a young adult female from Eastern Asia who has been adherent to a ketogenic diet. In contrast, we report a case of a Saudi male who did no dietary modifications, but underwent bariatric surgery. Treatment with minocycline resulted in successful complete resolution.

Use of minocycline for the treatment of prurigo pigmentosa with intraepidermal vesiculation: a case report

Pruritus pigmentosa is a skin disease mainly characterized by pruritus, inflammatory rash and reticular and macular pigmentation. The disease more commonly affects young women and may persist for several years. In this article, we report a case of a 20-year-old female patient who presented with erythema and blisters on the neck and trunk with pruritus for 20 days. Dermatological examination revealed a reticular distribution of erythema on the chest and abdomen and some areas of erythema covered with crusts. Additionally, blisters and bullae with clear fluid and negative Nikolsky's sign were noted. On the neck and back, erythema was also in a reticular distribution, and erythema secondary to erosion and/or crusts was present. In addition, histopathological analysis of the lesions showed hyperkeratosis and intraepidermal multilocular vesiculation and confirmed increased migration of inflammatory cells into the epidermis and infiltration of inflammatory cells, including lymphocytes, histiocytes and eosinophils, in the superficial dermis. The expression levels of IgG, IgM, IgA and C3 were all negative. This patient was diagnosed with prurigo pigmentosa, and the condition improved after treatment with minocycline.