To compare the positive rates of histopathology and multiple polymerase chain reaction (PCR) detection in different tissue specimens in surgery of brucellosis spondylitis.

From November 2018 to December 2019, 22 patients with brucellosis spondylitis underwent surgical treatment in Beijing Ditan Hospital, Capital Medical University, whose surgical sites were cervical spine (1 case), thoracic spine (2 cases), thoracolumbar spine (3 cases) and lumbar spine (16 cases); and 19 patients underwent posterior thoracolumbar debridement, decompression, internal fixation, bone graft fusion, 1 patient underwent cervical anterior debridement, decompression, internal fixation, bone graft fusion, 2 patients underwent foraminal debridement. Different tissue specimens (nucleus pulposus, soft endplate, ligamentum flavum, annulus fibrosus, etc.) were collected for Gimesa staining during the operation. While multiple PCR was performed on the tissue specimens, and the positive rates of both methods were comparatively analyzed by Fisher’s exact test.

Among the 22 patients, the positive rate of multiplex PCR was 90.9% (20/22), which was higher than Gimesa staining [81.8% (18/22)], but without significant difference (P = 0.664). Among the 73 tissue samples, the positive rate of multiplex PCR was 43.8% (32/73), which was higher than that of Gimesa staining [32.9% (24/73)], but without significant difference (P = 0.173). There were 22 samples of nucleus pulposus, and the positive rate of multiple PCR detection was 86.4% (20/22), which was higher than that of Gimesa staining [72.7% (16/22)], but without significant difference (P = 0.240). Among the 21 cartilage endplates, the positive rate of multiple PCR detection was 38.1% (8/21), which was higher than that of Gimesa staining [23.8% (5/21)], but without significant difference (P = 0.505). Among the 19 pieces of ligamentum flavum, the positive rate of multiple PCR was 10.5% (2/19), which was the same as Gimesa staining (2/19). Among the 11 pieces of annulus fibrosus, the positive rate of multiplex PCR was 18.2% (2/11), which was higher than that of Gimesa staining [9.1% (1/11)], but without significant difference (P = 1.000). However, the positive rates of both Gimesa staining and multiplex PCR from nucleus pulposus were significantly higher than those of other tissue samples, with significant difference (P < 0.001).

Multiplex PCR detection can be used as effective detection method for brucellosis spondylitis, with high sensitivity and accuracy, especially for patients with unclear preoperative diagnosis and negative postoperative pathological observation. Brucella mostly resides in the nucleus pulposus, which should be dealt with in the process of cleaning and collecting during operation.