1. Department of Orthopaedic Surgery, Groningen University Medical Centre, P O Box 30.001, 9700 RB Groningen, The Netherlands.
2. Department of Tuberculosis, GGD Nijmegen Region, Postbus 1120, 6501 BC Nijmegen, The Netherlands.
3. Department of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Centre, University of Amsterdam, Postbus 22660, 1100 DD Amsterdam, The Netherlands.