Granulomatous spondylodiscitis: A case series with focus on histopathological features

Objective: To report a series of Granulomatous Spondylodiscitis (GS) with focus on the histopathological features of the different forms of GS.Design: Case series.Setting: Pathology department of Charles Nicolle's Hospital of TunisiaParticipants: This study included 57 patients diagnosed with GS. There were 44 (77.2%) female patients and 13 (22.8%) male patients (sex ratio = 0.28).Intervention: Not applicable.Outcome measures: Clinical, microbiological and histopathological features were assessed in this study.Results: Fifty-seven patients with GS were enrolled: 51 tuberculous spondylodiscitis (TS), 2 fungal spondylodiscitis (FS), 3 brucellar spondylodiscitis (BS) and 1 case of sarcoidosis. Granulomas with necrosis were seen in 38 (66.6%) cases: 36 TS and 2 FS, while granulomas without necrosis were observed in the remaining 19 cases: 15 TS, 3 BS and 1 sarcoidosis. In all cases of TS, granulomas were epithelioid type, associated with histiocytic type granulomas in 7 cases. Caseous necrosis was seen in 35 cases of TS and suppurative granuloma in one case. The 3 cases of BS exhibited non-necrotizing and histiocytic type granulomas. The 2 cases of FS showed histiocytic, epithelioid and necrotizing granulomas. Necrosis was mixed: suppurative and caseous in both cases of FS. Sarcoidosis was characterized with epithelioid type granulomas without necrosis.Conclusion: Granuloma with caseous necrosis is highly suggestive of TS but does not rule out FS. Certain fungi can exhibit this type of necrosis as do tuberculosis species. Suppurative inflammation, although rare in TS, does exist. Histiocytic type granuloma without necrosis is suggestive of brucellosis.