FOLLOW-UP OF AN IMMUNOCOMPROMISED CONTACT GROUP OF A CASE OF OPEN PULMONARY TUBERCULOSIS ON A RENAL UNIT

Background- The organisation, management, outcome and cost of follow u p of a large group of mainly immuno-compromised patients and healthcar e workers who were exposed to a staff member of a London renal unit wi th smear positive pulmonary tuberculosis are described. Methods- Follo wing British Thoracic Society (BTS) guidelines, 576 close contacts wer e identified and divided into three groups: (1) 303 renal patients inc luding 61 with renal transplants; (2) 90 surgical patients; and (3) 18 3 staff members. Screened contacts were interviewed, completed a sympt oms questionnaire, and were offered a chest radiograph and Heaf or Man toux test if appropriate with referral to a chest physician if require d. Results- Overall, 524 (85%) Living contacts have been screened: 243 (97%) renal (first screening), 63 (70%) surgical, and 135 (74%) staff contacts. Thirty,one transplant patients ware prescribed isoniazid ch emo-prophylaxis. Fifty two renal patients had died before: screening a nd 11 deaths occurred after first interview. One case of tuberculosis epidemiologically related to the index case was diagnosed on clinical criteria. A review of the case records and/or death certificates and e ntries on to tuberculosis registers indicated no further cases. The co st of the investigation was estimated to be approximately pound 25 000 , or pound 44 per contact screened, with staff costs comprising 79% of the total. Conclusions - Undiagnosed tuberculosis in healthcare worke rs working with immunosuppressed patients can lead to large and expens ive follow up studies. The applicability of the 1990 and 1994 BTS guid elines to the investigation of tuberculosis in an immunocompromised no socomial group, and the role of the infection control doctor and the c onsultant in Communicable Disease Control in overlapping nosocomial an d community incidents, are discussed.