Hair and fingernail changes in acquired and congenital pernicious anemia.

Pigmentation changes limited to skin appendages accompanied pernicious anemia in four patients. Two Latin-American patients, one with congenital and one with acquired pernicious anemia, had reddish hair while they were cobalamin deficient. With treatment, the new hair growth assumed its normal premorbid dark brown color. Two black patients with pernicious anemia had blue fingernails. The new nail growth after treatment was of normal color. Pigmentation changes seem to be more frequent in nonwhite than in white patients with cobalamin deficiency and may have various expressions.