SECTION 15: ENDOCRINE, METABOLIC, AND NUTRITIONAL DISEASES

SKIN DISEASES ASSOCIATED WITH DIABETES MELLITUS

• Acanthosis nigricans (see Section 5) and lipodystrophy.

  Associated with insulin resistance in diabetes mellitus. Insulin-like epidermal growth factors may cause epidermal hyperplasia.

• Adverse cutaneous drug reactions in diabetes (see Section 23).

  Insulin: Local reactions—lipodystrophy with decreased adipose tissue at the sites of subcutaneous injection; Arthus-like reaction with urticarial lesion at site of injection.

  Systemic insulin allergy: Urticaria, serum sickness–like reactions.

  Oral hypoglycemic agents: Exanthematous eruptions, urticaria, erythema multiforme, and photosensitivity.

• Calciphylaxis (see Section 18).

• Cutaneous perforating disorders.

  Rare conditions in which horny plugs perforate into the dermis or dermal debris is eliminated through the epidermis. Not always associated with diabetes (see Section 18).

• Diabetic bullae (bullosis diabeticorum) (p. 379).

• Diabetic dermopathy (p. 381).

• Eruptive xanthomas (p. 391).

• Granuloma annulare (see Section 14).

• Infections (see Sections 25 and 26).

  Poorly controlled diabetes associated with increased incidence of primary and secondary Staphylococcus aureus infections, cellulitis (S. aureus, group A streptococcus), erythrasma, dermatophytoses, candidiasis, and mucormycosis with necrotizing nasopharyngeal infections.

• Necrobiosis lipoidica (p. 382).

• Peripheral neuropathy (diabetic foot) (p. 380).

• Peripheral vascular disease (see Section 17).

  Small-vessel vasculopathy (microangiopathy): Involves arterioles, venules, and capillaries. Characterized by basement membrane thickening and endothelial cell proliferation. Presents clinically as acral erysipelas-like erythema, and ± ulceration.

  Large-vessel vasculopathy: Incidence greatly increased in diabetes. Ischemia is most often symptomatic on lower legs and feet with gangrene and ulceration. Predisposes to infections.

• Scleredema diabeticorum.

  Synonym: Scleredema adultorum of Buschke. Need not be associated with diabetes. Onset correlates with duration of diabetes and with the presence of microangiopathy. Skin findings: Poorly demarcated scleroderma-like induration of the skin and subcutaneous tissue of the upper back, neck, and proximal extremities. Rapid onset and progression.

• Scleroderma-like syndrome. Scleroderma-like thickening of skin and limited joint mobility ("prayer sign").

DIABETIC BULLAE ICD-10: E14.650

• Large, intact bullae arise spontaneously on the lower legs, feet, dorsa of the hands, and fingers on noninflamed bases (Fig. 15-1).

• When ruptured, oozing bright red erosions result but heal after several weeks.

• Localization on dorsa of hand and fingers suggests porphyria cutanea tarda, but abnormalities of porphyrin metabolism are not found.

• Neither trauma nor an immunologic mechanism has been implicated. Histologically, bullae show intra- or subepidermal clefting without acantholysis.

"DIABETIC FOOT" AND DIABETIC NEUROPATHY ICD-10: E14.540

• Peripheral neuropathy is responsible for the "diabetic foot."

• Other factors are angiopathy, atherosclerosis, and infection; most often they are combined.

• Diabetic neuropathy is combined motor and sensory. Motor neuropathy leads to ...