Pars planitis in a family.

The familial occurrence of pars planitis is rare. We have found ten cases reported previously. We describe a new case of pars planitis in a family. The affected members included a mother and two of her four children. The family was tested for HLA antigens in order to establish a comparison with others HLA types by different authors. We have not identified any cause for the familial occurrence of this disease. We discuss the role of genetic and ambiental factors.