Clubbing may result from chronic low blood-oxygen levels. This can be seen with cystic fibrosis, congenital cyanotic heart disease, and several other diseases. The tips of the fingers enlarge and the nails become extremely curved from front to back.
Review Date: 1/18/2008 Reviewed By: Andrew Schriber, MD, FCCP, Specialist in Pulmonary, Critical Care, and Sleep Medicine, Virtua Memorial Hospital, Mount Holly, New Jersey. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.