Minocycline hyperpigmentation isolated to the subcutaneous fat

Abstract

We present a 15-year-old girl with bilateral lower extremity discoloration of one-year duration while taking minocycline for acne vulgaris. The clinical characteristics best supported type II minocycline hyperpigmentation, but the histology revealed that the pigmentation was solely limited to the subcutaneous adipose tissue, completely sparing the dermis. Special stain for iron was negative. This is the first case to our knowledge with pigment exclusively located in the subcutaneous fat and with the unusual finding of a negative stain for iron.

The histopathology of subcutaneous minocycline pigmentation

“…These globules were a consistent finding in all of our cases; curiously, these globules do not consistently label with special staining. We are aware of one other case of minocycline hyperpigmentation limited to the subcutaneous fat 11 showing similar brown-staining globules in the subcutis. Pigmented lipomembraneous changes are variably present in our series and did not correlate with trauma history.…”

Feeling blue? Minocycline-induced staining of the teeth, oral mucosa, sclerae and ears – a case report

“…In addition to the sites described in the case report above, minocycline has also been known to cause pigmentation in the thyroid, nails, bone, subcutaneous fat and skin. 2,7,10,15,16,26,30,31 There have been suggestions that there may a relationship with thyroid function and Vitamin C use. 3 Therefore it may be worthwhile considering these factors before prescribing long-term minocycline, but further evidence is required to support these theories.…”

Minocycline in Acne Vulgaris

“…[68][69][70][71][72][73] Although cutaneous or oral mucosal pigmentation may appear regardless of the dose or duration of therapy, pigmentation generally results from long-term administration of minocycline at cumulative doses >100 g. The bones of the oral cavity are probably the most frequently affected sites of pigmentation, affecting about 10% of patients treated for more than 1 year. If treated for longer than 4 years, more than 20% of patients taking minocycline were affected.…”