Xu-Wen Fu,1,* Yan Bi,2,* Jia-Lu Wei,3 Min Qi,3 Long Zhu,3 Ying Pu,3 Jing-Liang Liu,2 Xiang Li,3 Xin-Hua Cun4 

1Department of Pharmacy, Kunming Third People’s Hospital/Yunnan Clinical Medical Center for Infectious Diseases, Kunming, 650041, People’s Republic of China; 2Department of Radiology, The People’s Hospital of Lincang, Lincang, 677000, People’s Republic of China; 3Department of Radiology, Kunming Third People’s Hospital/Yunnan Clinical Medical Center for Infectious Diseases, Kunming, Yunnan, 650200,People’s Republic of China; 4Department of Orthopaedics, Kunming Third People’s Hospital/Yunnan Clinical Medical Center for Infectious Diseases, Kunming, 650041, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Xiang Li, Department of Radiology, Kunming Third People’s Hospital/Yunnan Clinical Medical Center for Infectious Diseases, Kunming, Yunnan, 650041, People’s Republic of China, Tel +86 18108857532, Email li_xiang115@126.com Xin-Hua Cun, Department of Orthopaedics, Kunming Third People’s Hospital/Yunnan Clinical Medical Center for Infectious Diseases, Kunming, Yunnan, 650041, People’s Republic of China, Email xinhuacun_cun6@21cn.com

Objective: To observe the clinical characteristics of fungal and Brucella infections of the lumbar spine and explore the key points for their differential diagnosis.
Methods: The clinical data of 12 patients with fungal infection (the fungal group) and 31 patients with Brucella infection (the Brucella group) of the lumbar spine confirmed by microbiological culture and antigen test were retrospectively analysed. The differences in the clinical characteristics and imaging manifestations were observed between the two groups.
Results: The peripheral blood neutrophil ratio, erythrocyte sedimentation rate, serum total protein and serum globulin levels in the fungal group were higher compared with the Brucella group, while the peripheral blood lymphocyte count, lymphocyte ratio and albumin-globulin ratio were lower in the fungal group compared with the Brucella group (P < 0.05). As for imaging examinations, the proportion of bone destruction centred on the intervertebral disc with surrounding osteosclerosis on computed tomography (CT) imaging showed a statistical difference between the Brucella group and the fungal group (P < 0.05). Fungal infection patients showed more osteosclerosis-free areas around the bone destruction on magnetic resonance imaging (MRI) than Brucella infection patients.
Conclusion: There are certain similarities in clinical manifestations between fungal and Brucella infections of the lumbar spine, but the haematological indices and image features of CT and MRI can effectively differentiate between them, providing guidance for the clinical differential diagnosis.

Keywords: mycosis, brucellosis, imaging, differential diagnosis