Posts Tagged ‘exogenous ochronosis’

Exogenous Ochronosis

Friday, December 13th, 2013

Endogenous ochronosis (also called alcaptonuria) is a rare autosomal regressive disorder where there is enzymatic deficiency of homongentisic acid oxydase (AHG). This results in accumulation of AHG which is oxydized and polymerized in a substance close to melanin called benzoquinone acetic acid (ABQA). Its accumulation in the skin results in the clinical pigmentation.   The […]

Using Hydroquinone and Ochronosis

Wednesday, May 16th, 2012

Rule No: 1 Recognize melasma (chloasma, pregnancy mask) Rule out the differential diagnoses: lichen planus pigmentosus (darker skin patients (Indians), pigmentation is often seen behind the ears) Hori’s Nevus Drug-induced hyperpigmentation ochronosis Rule No: 2 If the patient reports worsening of melasma with hydroquinone use, consider seriouslsy the diagnosis of ochronosis: Stage 3 ochronosis is […]

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