The most prominent cause of horizontal white lines running across the finger nails is a chronic nutritional deficiency of a protein known asalbumin; patients are therefore treated using infusions of albumin. The albumin infusion increases the serum levels, causing the white lines to gradually disappear.
The white bands may be a symptom of an underlying disease, in which case treating the disease will correct the albumin levels. For example, albumin is produced in the liver and is usually present in the blood, which means thatthe white lines may be a symptom of liver disease. The condition is referred to Muehrcke lines and was named after Robert Muehrcke, the doctor who first describe it in 1956, as reported by WebMD.