This is a group of inherited disorders involving abnormalities in the production of heme pigments (the base material responsible for hemoglobin/red blood cell pigment) and myoglobin (reddish muscle cell pigment).
"¢ Red urine
"¢ Sensitivity to sunlight
"¢ Blister (bulla) formation on exposure to sunlight
"¢ Skin swelling (edema) on exposure to sunlight
"¢ Crampy abdominal pain (may be extremely severe)