[Significance of leukocyte scintigraphy of the infected total endoprosthesis]

Abstract

31 patients with suspected septic loosening of an endoprosthesis (hip endoprosthesis n = 30; knee endoprosthesis n = 1) were examined with leukocyte scans (10 MBq 111In-oxine: n = 22; 300 MBq 99mTc-HMPAO: n = 9). The results were compared with results of the bacterial growth (n = 22), the histology (n = 12) and of the bone scans (99mTc-MDP: n = 20) which were performed within 4 days. The sensitivity of the bone scan was 100%, the specificity 30% and the diagnostic accuracy regarding a septic loosening of the arthroplasty was 55%. For the leukocyte scans a comparable sensitivity of 100%, but a higher specificity (86%) and accuracy (91%) could be calculated. A false positive leukocyte scan could be observed in a periprosthetic granuloma, an ossifying periarthritis and in a patient with negative bacterial growth with the histological proof of an inflammation.