Yellow Nail Syndrome and Half-and-Half Nail

To the Editor.—  The yellow nail syndrome as originally described in 1964 by Samman and White¹ presented a picture of diffuse yellow discoloration of the nail plate associated with lymphedema. In addition, there was a striking absence of cuticles and very slow nail-plate growth with both longitudinal and transverse overcurvature. Onycholysis proceeding to total shedding was also a prominent feature. Two years later, in 1966, Emerson² added the finding of pleural effusion, completing the symptom triad as it is known today. This third manifestation often occurred together with sinusitis, bronchitis, and bronchiectasis.The half-and-half nail of Lindsay,³ first described in 1963 by Bean,⁴ detailed a nail-bed change in which the proximal half was white and the distal portion red to brown. This picture was noted most commonly in patients with chronic renal disease in whom serum nitrogen levels were usually elevated.⁵ In addition to the nail-bed change, there may also be associated the presence of melanin in the acral part of the nail plate itself, thus involving a second component of the nail unit. The half-and-half nail may also be seen in patients without any demonstrable systemic abnormality.