Yellow nail syndrome is a rare medical condition that is characterized by significant changes in an individual's nails. The nails thicken dramatically, turn a yellow-to-yellow-green color and can separate from the nail bed. Additional complications can include swelling of the body, usually in the arms and legs, as well as damage to the upper airways and lungs.
An individual who is affected by yellow nail syndrome typically experiences changes in the nails of the hands and feet, and all of the nails can be involved. Affected nails might be slow growing or might have stopped growing altogether. The nails can have ridges across them and develop humps. Additionally, the edges of the nails might appear dark, and there might be a loss of the cuticle. In most cases, the nail changes are permanent, although there have been instances in which the nails have returned to their normal state.
Although the cause of yellow nail syndrome remains unknown, the malady is commonly accompanied by one or more ailments, including lymphoedema, pleural effusions, bronchiectasis, chronic bronchitis and sinus infections. Lymphoedema is caused by a blockage of the lymphatic system. The lymphatic system works in tandem with the circulatory system to deliver oxygen, nutrients and hormones to the cells and with the immune system to filter out harmful disease-causing organisms in the body. When the lymphatic system gets a blockage, it typically causes swelling. Individuals who have lymphoedema generally have swelling in their arms or legs as a result of the accumulation of lymph fluid that is unable to drain properly.
Pleural effusions occur in roughly 36 percent of people who are affected by yellow nail syndrome. When excess fluid accumulates in the space surrounding the lungs, the accumulations are commonly referred to as pleural effusions. The excessive fluid buildup in the lungs impairs breathing by limiting the expansion of the lungs during inhalation.
Typically, about 40 percent of individuals who have yellow nail syndrome also have a condition called bronchiectasis. This ailment is caused by damage to the airways, also called the bronchial tubes, which carry air to and from the lungs. The damage usually is the result of chronic infections that have produced scar tissue. Bronchiectasis causes these airways to widen in order to compensate for the buildup of scar tissue.