Scleredema

Specialty: Skin.

• Buschke scleredema
• mucinous hardening of the skin

Why it occurs

• Abnormal deposition of collagen and mucopolysaccharides (mucin) in the deep reticular dermis of idiopathic origin
• Long-term insulin-dependent diabetes mellitus with poor chronic metabolic control (scleredema diabeticorum)
• Previous acute febrile respiratory infection (especially streptococcal pharyngotonsillitis due to group A streptococci, common in children and young women)
• Presence of concomitant monoclonal gammopathy of undetermined significance (MGUS) or multiple myeloma
• Autoimmune disorders of the thyroid or underlying connective tissue.

Initial workup

Deep skin biopsy by punch or incision that reaches the subcutaneous tissue to demonstrate thickening of the reticular dermis (up to 3 times the normal size) with collagen bundles separated by clear spaces that stain positively for mucopolysaccharides with Alcian blue or colloidal iron, without a significant increase in the number of fibroblasts. Protein electrophoresis and immunofixation in serum and urine, glycosylated hemoglobin (HbA1c) and throat swab.

Standard management

• Optimization of strict glycemic control with insulin in diabetic patients — fundamental measure in scleredema diabeticorum
• Benzathine penicillin — indicated if active or recent streptococcal infection is confirmed in the post-infectious type
• Methotrexate — systemic immunosuppressant indicated in refractory extensive progressive forms, dose of 15 to 25 mg/week
• Phototherapy with UVA-1 or PUVA bath (first choice therapy to promote collagen degradation through the induction of dermal collagenase metalloproteinases).