Department of Orthopaedics, Affiliated Hospital of Guizhou Medical University, Guiyang, 550001, Guizhou, China.
School of Clinical Medicine, Affiliated Hospital of Guizhou Medical University, Guiyang, 550001, Guizhou, China.
BMC Infect Dis. 2024 Jun 26;24(1):643. doi: 10.1186/s12879-024-09512-9.
Malassezia restricta, a lipophilic and lipodependent yeast belonging to the basidiomycetes group, is an opportunistic fungal pathogen associated with various skin diseases, including seborrheic dermatitis and dandruff. Typically, Malassezia infection in neonates manifests as fungemia or hematogenous dissemination to the bone or lungs. However, vertebral osteomyelitis caused by these fungi is rarely reported owing to non-specific clinical presentations and laboratory/imaging findings. The Pathogen Metagenomics Sequencing (PMseq) technique enables direct high-throughput sequencing of infected specimens, facilitating the rapid and accurate detection of all microorganisms in clinical samples through comprehensive reports.
A 52-year-old male was admitted to our hospital on July 20, 2022 with a 3-month history of ambulatory difficulties and localized low back pain. Magnetic Resonance Imaging (MRI) examination of the spinal column revealed irregular bone destruction affecting the L2, L3, and L5 vertebral bodies. Additionally, low T1 and high T2 intensity lesions were observed at the intervertebral discs between L3 and L5. The presumptive diagnosis of tuberculous spondylitis was made based on the imaging findings, despite negative results in all mycobacterium tests. However, the patient exhibited no improvement after receiving regular anti-tuberculosis treatment for 3 months. Subsequent MRI revealed an expansive abnormal signal within the vertebral body, leading to progressive bone destruction. The absence of spinal tuberculosis or other infective microorganisms was confirmed through culture from blood and pathological tissue from the L4 vertebral body. Subsequently, PMseq was performed on the specimens, revealing M. restricta as the predominant pathogen with the highest relative abundance value. The pathological examination revealed the presence of fungal mycelium in the L4 vertebral body, with positive findings on periodic Schiff-methenamine and periodic acid-Schiff staining. The anti-tuberculosis treatment was discontinued, and an antifungal combination of fluconazole and voriconazole was administered. All symptoms were resolved after 7 consecutive months of treatment, and the patient was able to ambulate autonomously. Vertebral lesions were reduced on MRI during the 13-month follow-up.
M. restricta is not a commonly recognized pathogen associated with infectious vertebral osteomyelitis. However, PMseq can aid in diagnosis, timely treatment, and decision making for some non-specific infectious diseases.
限制马拉色菌是一种亲脂性和脂肪依赖性酵母，属于担子菌组，是一种与各种皮肤疾病相关的机会性真菌病原体，包括脂溢性皮炎和头皮屑。通常，新生儿的马拉色菌感染表现为菌血症或血源性播散到骨骼或肺部。然而，由于非特异性临床表现和实验室/影像学发现，这些真菌引起的脊椎骨骨髓炎很少报道。病原体宏基因组测序（PMseq）技术可直接对受感染的标本进行高通量测序，通过全面报告，快速准确地检测临床样本中的所有微生物。
一名 52 岁男性于 2022 年 7 月 20 日因 3 个月的步行困难和局部下腰痛入院。脊柱磁共振成像（MRI）检查显示 L2、L3 和 L5 椎体不规则骨破坏。此外，L3 和 L5 椎间盘之间观察到低 T1 和高 T2 强度病变。尽管所有分枝杆菌检测均为阴性，但根据影像学表现，诊断为结核性脊柱炎。然而，尽管接受了 3 个月的常规抗结核治疗，患者仍未改善。随后的 MRI 显示椎体内部有扩张性异常信号，导致进行性骨破坏。通过血液和 L4 椎体病理组织培养均未发现脊柱结核或其他感染性微生物。随后对标本进行 PMseq 检测，结果显示 M. restricta 为主要病原体，相对丰度值最高。L4 椎体的病理学检查显示存在真菌菌丝，过碘酸雪夫氏和过碘酸希夫氏染色阳性。停止抗结核治疗，给予氟康唑和伏立康唑联合抗真菌治疗。连续治疗 7 个月后，所有症状均得到缓解，患者可自主活动。在 13 个月的随访中，MRI 显示椎体病变减少。
M. restricta 不是引起感染性脊椎骨骨髓炎的常见病原体。然而，PMseq 有助于诊断、及时治疗和决策一些非特异性传染病。
