​Differential diagnosis of pigmentation

​Differential diagnosis of pigmentation 
-POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) 
-visceral leishmaniasis ( kala azar) 
-berloque hyperpigmentation ( phototoxicty from citrus or celery)
-exogenous pigment exposure ( carotenemia, argyria, gold, tattooing, arsenic)
-fixed drug eruption to laxatives ( phenolphthalein), trimethoprim-sulfamethoxazole, NSAIDS, tetracycline
-medications such as chloroquine, chlorpromazine, minocycline, amiodarone
-folate deficiency 
-vitamin B12 deficiency 
-scleroderma 
-Whipple’s disease
-Wilson’s disease
-porphyria cutanea tarda 
-pellagra (niacin deficiency) 
-ochronosis ( alkaptonuria) 
-hyperbilirubinemia such as primary biliary cirrhosis 
-acanthosis nigricans 
-Addison’s disease
-hemochromatosis 
-heurofibromatosis ( café au lait spots, axillary freckling)
-melasma (chloasma)