Skin testing, PPD (R arm) and Candida (L):

The right arm represents a positive reaction to PPD (a skin test for tuberculosis protein). The left arm represents a positive reaction to Candida protein. Candida antigen is tested to determine if the individual's immune system is functioning well; a normal immune system demonstrates a positive reaction.
- Reviewed last on: 5/25/2009
- Stuart I. Henochowicz, MD, FACP, Associate Clinical Professor of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.