Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai, Miyagi, Japan.
Tohoku J Exp Med. 2013 Sep;231(1):13-9. doi: 10.1620/tjem.231.13.
Recently, aging population and immuno-compromised patients have been rising in Japan. Accordingly, patients with pyogenic spondylitis have been increasing and may present atypical clinical features. University hospitals treat many elderly patients and patients with poor general condition. Therefore, patients with pyogenic spondylitis treated at two university hospitals were retrospectively investigated to clarify the recent clinical and radiologic characteristics of this infection. There were 30 patients (average age: 68 years) treated in two university hospitals between 2009 and 2010. The onset was acute or subacute in 15 patients, insidious in 7 and unclassified in 8. Culture tests were performed in 25 patients, and the causative microorganisms were identified in 20 patients with the identification rate of 80%, including 4 patients infected by methicillin-resistant staphylococci. Classically, active pyogenic spondylitis is characterized by typical findings on magnetic resonance imaging (MRI): obvious signal decrease in T1-weighted image (WI) and increase in T2WI with contrast enhancement found in most of the bodies of two adjacent vertebrae and the intervening intervertebral disc. Among 29 patients with active pyogenic spondylitis, whose lesions were not in the healing stage, 16 patients demonstrated at least one of the atypical MRI findings; 9 patients showed involvement ≥ 3 vertebrae or only 1 vertebra, 5 showed the signal changes of the lesions involving small, spotty, or faint areas, and 3 showed small vertebral lesions but larger epidural or paraspinal abscesses. In conclusion, currently, about half of the patients with pyogenic spondylitis demonstrate atypical MRI findings in the university hospitals in Japan.
近年来，日本的人口老龄化和免疫功能低下患者不断增加。因此，化脓性脊柱炎患者也在增加，且可能表现出非典型的临床特征。大学医院治疗许多老年患者和一般情况较差的患者。因此，对在两所大学医院治疗的化脓性脊柱炎患者进行了回顾性调查，以明确这种感染的近期临床和影像学特征。在 2009 年至 2010 年期间，两所大学医院共治疗了 30 例患者（平均年龄：68 岁）。15 例患者起病急或亚急性，7 例起病隐匿，8 例起病未分类。25 例患者进行了培养试验，20 例患者确定了病原体，检出率为 80%，包括 4 例耐甲氧西林葡萄球菌感染。典型的活动性化脓性脊柱炎在磁共振成像（MRI）上具有典型表现：在大多数相邻两个椎体及其椎间盘的体部和介入的椎间盘上，T1 加权像（WI）信号明显降低，T2WI 信号增强。在 29 例活动性化脓性脊柱炎患者中，有 16 例病变未处于愈合阶段，其至少存在一种非典型 MRI 表现；9 例累及≥3 个椎体或仅 1 个椎体，5 例病变信号改变累及小、点状或模糊区域，3 例病变椎体较小但硬膜外或椎旁脓肿较大。总之，目前日本大学医院约有一半的化脓性脊柱炎患者表现出非典型的 MRI 表现。
