Keto Rash: Ketoacidosis-Induced Prurigo Pigmentosa

A 37-year-old male patient has suffered from pruritic eruptions for 2 weeks and had a weight loss of 20 kg in 3 months. Associated symptoms included drowsiness, generalized weakness, nausea, nocturia, polydipsia, and polyphagia. On examination, pruritic erythematous papuloplaques mixed with brownish reticular hyperpigmentation were noted mainly on the back (Figure 1). Laboratory data revealed a serum glucose level of 805 mg/dL (44.68 mmol/L), high glycohemoglobin level (17.5%; reference range:<5.7 %), high serum level (7.2 mmol/L; reference range, <0.6 mmol/L), and high urinary ketone level (4+; reference range, negative). Histopathology revealed basket weave hyperkeratosis and perivascular lymphocytic infiltrate with many neutrophils in the dermis (Figure 2). On the basis of clinical and pathological findings, prurigo pigmentosa associated with diabetic ketoacidosis (keto rash) was diagnosed. Slit-lamp examination suggested no diabetic retinopathy. The patient received glucose-insulin-potassium and fluid regimen for diabetes ketoacidosis control. The skin eruption responded well with gradual resolution 2 weeks after the above-mentioned management and topical steroid treatment.Figure 2A, Histopathology revealed basket weave hyperkeratosis, parakeratosis, and superficial perivascular inflammatory cells infiltration in the upper dermis (hematoxylin and eosin stain, original magnification 40×). B, In higher magnification, sections revealed mild exocytosis, basal cell vacuolization, and superficial perivascular lymphocytic infiltration with neutrophils (hematoxylin and eosin stain, original magnification 200×).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Prurigo pigmentosa causes acquired diffuse reticulate pigmented eruptions on the trunk and commonly affects young patients.1Rotstein H. Mason G.H. A peculiar pruriginous dermatoses with gross reticular pigmentation.Australas J Dermatol. 1992; 33: 56-59Crossref PubMed Scopus (6) Google Scholar It is characterized by intensely pruritic symmetrical urticarial, erythematous papuloplaques coalescing into reticulated hyperpigmentation, which is usually distributed on the trunk and neck. The pathomechanisms are proposed to be neutrophil-mediated inflammation triggered by metabolic and environmental factors, and the role of ketoacidosis is increasingly reported.2Beutler B.D. Cohen P.R. Lee R.A. Prurigo pigmentosa: literature review.Am J Clin Dermatol. 2015; 16: 533-543Crossref PubMed Scopus (49) Google Scholar Patients with the underlying disease of anorexia nervosa and diabetes and on a ketogenic diet may be at a high risk of developing prurigo pigmentosa. With an increasing prevalence of ketogenic diets, the cases of prurigo pigmentosa are more commonly reported.3Michaels J.D. Hoss E. DiCaudo D.J. Price H. Prurigo pigmentosa after a strict ketogenic diet.Pediatr Dermatol. 2015; 32: 248-251Crossref PubMed Scopus (20) Google Scholar Management includes controlling blood sugar level and treatment with minocycline, doxycycline, or dapsone. Here, we present this case to raise awareness of distinct skin eruptions that can occur in the setting of diabetic ketoacidosis, or in patients on a ketogenic diet.