MRI and clinical features of acute fungal discitis/osteomyelitis.

OBJECTIVES: To compare imaging and clinical features of fungal and Staphylococcus aureus discitis-osteomyelitis (DO) for patients presenting for CT-guided biopsies. METHODS: Our study was IRB-approved and HIPAA-compliant. A group of 11 fungal DO (FG) with MRI within 7 days of the biopsy and a control group (CG) of 19 Staphylococcus aureus DO were evaluated. Imaging findings (focal vs diffuse paravertebral soft tissue abnormality, partial vs complete involvement of the disc/endplate), biopsy location, pathology, duration of back pain, immune status, history of intravenous drug, history of prior infection, current antibiotic treatment, and history of invasive intervention. Differences were assessed using the Fisher exact test and Kruskal-Wallis test. Naïve Bayes predictive modeling was performed. RESULTS: The most common fungal organisms were Candida species (9/11, 82%). The FG was more likely to have focal soft tissue abnormality (p = 0.040) and partial disc/endplate involvement (p = 0.053). The clinical predictors for fungal DO, in order of importance, back pain for 10 or more weeks, current antibiotic use for 1 week or more, and current intravenous drug use. History of invasive instrumentation within 1 year was more predictive of Staphylococcus aureus DO. CONCLUSION: MRI features (focal partial soft tissue abnormality and partial involvement of the disc/endplate) in combination with clinical features may help to predict fungal species as a causative organism for DO. KEY POINTS: • MRI features of discitis-osteomyelitis (focal partial soft tissue abnormality and partial involvement of the disc/endplate) in combination with clinical features may help to predict fungal species as a causative organism for DO.

IgM Augments Complement Bactericidal Activity with Serum from a Patient with a Novel CD79a Mutation.

Antibody replacement therapy for patients with antibody deficiencies contains only IgG. As a result, concurrent IgM and IgA deficiency present in a large proportion of antibody deficient patients persists. Especially patients with IgM deficiency remain at risk for recurrent infections of the gastrointestinal and respiratory tract. The lack of IgM in the current IgG replacement therapy is likely to contribute to the persistence of these mucosal infections because this antibody class is especially important for complement activation on the mucosal surface. We evaluated whether supplementation with IgM increased serum bactericidal capacity in vitro. Serum was collected from a patient with agammaglobulinemia and supplemented with purified serum IgM to normal levels. Antibody and complement deposition on the bacterial surface was determined by multi-color flow cytometry. Bacterial survival in serum was determined by colony-forming unit counts. We present a patient previously diagnosed with agammaglobulinemia due to CD79A (Igα) deficiency revealing a novel pathogenic insertion variant in the CD79a gene (NM_001783.3:c.353_354insT). Despite IgG replacement therapy and antibiotic prophylaxis, this patient developed a Campylobacter jejuni spondylodiscitis of lumbar vertebrae L4-L5. We found that serum IgM significantly contributes to complement activation on the bacterial surface of C. jejuni. Furthermore, supplementation of serum IgM augmented serum bactericidal activity significantly. In conclusion, supplementation of intravenous IgG replacement therapy with IgM may potentially offer greater protection against bacterial infections, also in the context of increasing antibiotic resistance.

Bioengineered three-dimensional diseased intervertebral disc model revealed inflammatory crosstalk.

Without an appropriate disease model, the understanding of the pathophysiology of intervertebral disc degeneration and inflammation is limited. The lack of understanding limits the potential discovery of therapeutic targets as viable treatment options. Here, we report a versatile method to develop a three-dimensional intervertebral disc (IVD) model to study the response of nucleus pulposus (NP) and annulus fibrosus (AF) cells to inflammatory (IL-1ß-induced) stimulation. The cell shape regulated IVD model was engineered by modulating the crosslinking of a self-assembled collagen hydrogel. The developed model has provided us with an understanding of the molecular changes that occur at genetic level which modulate the production of extracellular matrix components and key inflammatory pathways in the inflamed IVD. We have identified the role of the suppressor of cytokine proteins (SOCS) family in combating detrimental effects of pro-inflammatory cytokines in degenerated human NP tissue as predicted by the developed diseased model. The model could also provide an understanding of the expression of glycans implicated in the diseased IVD.

Aseptic HLA B27-positive spondylodiscitis: decreased 18F-FDG uptake after etanercept treatment.

We observed a 69-year old man suffering from HLA B27 ankylosing spondylitis with persistent night back pain. 18F-FDG-PET/CT showed an increased metabolism at the level of the spinal space of L2-L3, L3-L4 with increased uptake compatible with spondylodiscitis. He started therapy with etanercept 50 mg/week. After six months of treatment repeated testing showed no uptake of the discs and vertebral bodies.

Case Series of Iliopsoas Abscesses Treated at a University Hospital in Japan: Epidemiology, Clinical Manifestations, Diagnosis and Treatment.

OBJECTIVE: The incidence of iliopsoas abscesses has been increasing due to advances in diagnostic imaging techniques and the increased number of elderly individuals and immunodeficient patients with co-morbidities. Our aim was to investigate the management and treatment of iliopsoas abscesses, particularly the effectiveness of computed tomography (CT)-guided drainage in the era of interventional radiology. METHODS: A retrospective analysis was performed at a university hospital between January 2009 and March 2014. Patients There were 15 patients (eight men, seven women) 50-85 years of age (average: 70 years) diagnosed with an iliopsoas abscess. RESULTS: The etiology of the disease was investigated in 14 of the 15 patients, each of whom had a secondary iliopsoas abscess. The primary condition in nine of these patients (64.3%) was an orthopedic infection (spondylodiscitis); the most common symptom was fever (12 patients, 80%). Altogether, 10 patients (66.7%) had a multilocular abscess and five (33.3%) had bilateral abscesses. The most common pathogen was Staphylococcus aureus (seven patients, 50%). All 14 patients underwent drainage: 11 received CT-guided drainage, two underwent postdrainage surgery and one received ultrasonography-guided drainage. Poor drainage was overcome by inserting multiple drainage tubes (six patients) or performing transmembrane drainage with a guidewire. All but one patient survived. CONCLUSION: Based on the high success rate of CT-guided drainage in this study, this technique is expected to continue to play a major role in cases requiring drainage, even in patients with bilateral or multilocular abscesses. However, this modality cannot be used in cases of gastrointestinal perforation.

A Minimally Invasive Endoscopic Surgery for Infectious Spondylodiscitis of the Thoracic and Upper Lumbar Spine in Immunocompromised Patients.

This study evaluates the safety and effectiveness of computed tomography- (CT-) assisted endoscopic surgery in the treatment of infectious spondylodiscitis of the thoracic and upper lumbar spine in immunocompromised patients. From October 2006 to March 2014, a total of 41 patients with infectious spondylodiscitis underwent percutaneous endoscopic surgery under local anesthesia, and 13 lesions from 13 patients on the thoracic or upper lumbar spine were selected for evaluation. A CT-guided catheter was placed before percutaneous endoscopic surgery as a guide to avoid injury to visceral organs, major vessels, and the spinal cord. All 13 patients had quick pain relief after endoscopic surgery without complications. The bacterial culture rate was 77%. Inflammatory parameters returned to normal after adequate antibiotic treatment. Postoperative radiographs showed no significant kyphotic deformity when compared with preoperative films. As of the last follow-up visit, no recurrent infections were noted. Traditional transthoracic or diaphragmatic surgery with or without posterior instrumentation is associated with high rates of morbidity and mortality, especially in elderly patients, patients with multiple comorbidities, or immunocompromised patients. Percutaneous endoscopic surgery assisted by a CT-guided catheter provides a safe and effective alternative treatment for infectious spondylodiscitis of the thoracic and upper lumbar spine.

Microbiological and immunological diagnosis of tuberculous spondylodiscitis.

BACKGROUND: Tuberculous spondylodiscitis is one the many manifestations of active tuberculosis (TB) and can result following primary infection or, more frequently, from reactivation of active TB in subjects with latent TB. Definitive diagnosis of tuberculous spondylodiscitis requires the identification of Mycobacterium tuberculosis in the biological sample following microbiological analysis. AIM: To summarize the recent advancement in the diagnosis of TB, focusing on classical and molecular microbiological procedures, providing an overview on the recent advancements in the understanding of TB pathogenesis and their implications for the immunological diagnosis MATERIALS AND METHODS: Isolation in culture of the bacilli and detection using molecular tools are the gold standards, though sensitivity of these assays is significantly lower compared to what observed for pulmonary TB, making diagnosis of spinal TB challenging. RESULTS: The use of the interferon-gamma release assays (IGRAs) for the immunological diagnosis of TB infection could be of help and shall precede the invasive techniques, such as biopsy or surgery, required to obtain the biological sample. IGRAs measure the presence of effector T cells in the blood that can readily respond to an antigenic stimuli by secreting cytokines, and that are an indication of the presence of the bacilli in vivo. IGRAs are more sensitive and specific than the intradermic reaction of Mantoux, though both these immunological tests cannot distinguish between latent TB infection and active TB. CONCLUSIONS: A modern diagnosis of TB spondylodiscitis should rely on the use of microbiological and immunological assays and the latter could potentially be of great help in monitoring therapy effectiveness.

Fungal thoracic Spondylodiskitis in an immunocompetent 14-year-old girl.

Fungal spondylodiskitis (inflammation of intervertebral disk tissue and adjacent vertebrae) is rare, particularly in immunocompetent patients. Here, we report a case of fungal and bacterial thoracic spondylodiskitis in a 14-year-old girl with abdominal and back pain. The spondylodiskitis was diagnosed on the basis of the presence of beta-D glucan and the unusual clinical course, although cultures for fungus were negative. We conclude spondylodiskitis must be considered in cases of abdominal pain without clear etiology and in cases of fungal infection with unexplainable findings after standard treatment for bacterial infection, even when fungal cultures are negative.

Treatment of spondylodiscitis in human immunodeficiency virus-infected patients: a comparison of conservative and operative therapy.

STUDY DESIGN: Multicenter retrospective case series. OBJECTIVE: To determine relevant clinical presentation and outcome of human immunodeficiency virus (HIV)-positive patients with spondylodiscitis as a function of the treatment. SUMMARY OF BACKGROUND DATA: This is the first study comparing the clinical outcome of HIV-positive patients with spondylodiscitis as a function of the treatment. METHODS: We performed a national multicenter retrospective case series comparing operatively versus conservatively treated HIV-positive patients with spondylodiscitis presenting between 1991 and 2007. RESULTS: Twenty patients were included in the study. The average age of the patients at the time of admission was 43.0 years. The sex ratio m:w resulted in 2.3:1. On admission, 50% of the patients were in CDC stage C3. The CD4 T-cell count was determined as being 237.5/microL on average. At the occurrence of spondylodiscitis HIV had been known for a mean 8.5 years. In altogether 75% of the cases a pathogen was found. In 3 cases, mixed infections were present. Half of the patients received surgery. In none of these patients a wound infection or a delay of wound healing could be observed. One patient died during in-patient stay. Eleven of the 19 patients could be followed up a mean 13 months after discharge. In the follow-up period further 3 patients died on an average of 45 months after discharge. CONCLUSION: The occurrence of spondylodiscitis in HIV-positive patients is associated with a low CD4 T-cell count. The probability of mixed infections rises with a CD4 T-cell count <100/microL. The occurrence of spondylodiscitis in HIV-positive patients is accompanied by high mortality. Operative therapy of spondylodiscitis in HIV-positive patients is not associated with an increased surgical complication rate. HIV infection or AIDS should not have an influence on decision-making regarding conservative or operative therapy of spondylodiscitis.

Spondylodiscitis caused by Mycobacterium xenopi.

The infection with non-tuberculous mycobacterium correlates highly with immunodeficiency. Mycobacterium xenopi (M. xenopi) is most commonly isolated in the respiratory tract, as a cause of endogenous spondylodiscitis it occurs but rarely. Only seven such cases have been reported in literature. In this paper, we present the case of an about 28-year-old HIV-positive patient with a long history of back pain. MRI of the spinal column and Positron Emission Tomography with (18)F-fluorodeoxyglucose as a tracer (F18-FDG-PET) confirmed the suspected spondylodiscitis. After performing a CT-controlled abscess drainage the patient's condition improved. Because of the severe destruction of the spinal segment concerned and because of the epidural abscess formation a vertebrectomy of T10 and surgical debridement of the paravertebral soft tissue via thoracotomy became urgently necessary. The spine was stabilized by interposing a cage and an anterolateral monobar system. M. xenopi could be proven by PCR out of the intraoperative specimen. After operation and antituberculotic therapy there was a fast convalescence. Diagnostics, therapy, and clinical outcome are discussed.

Bone and joint infection due to Streptococcus pneumoniae in two immunocompetent adults.

Bone and joint infections due to Streptococcus pneumoniae are uncommon in adults in the absence of risk factors (e.g. alcohol abuse, immunodepression, or preexisting joint disease). We report two cases in previously healthy adults. The clinical picture was septic arthritis of the knee in one patient and discitis with an extensive epidural abscess in the other. The characteristics of S. pneumoniae bone and joint infections are reviewed, with emphasis on risk factors. The therapeutic strategy is discussed in the light of the recent upsurge in S. pneumoniae strains with reduced susceptibility to penicillin.

Early histology in ankylosing spondylitis related spondylodiscitis supports its inflammatory origin.

It is unclear whether the destructive lesions of the vertebral bodies in the spondylodiscitis of ankylosing spondylitis (AS) are related to mechanical stress or inflammation. We describe early immunohistopathological findings in an AS patient with severe symptomatic spondylodiscitis that support an inflammatory origin.

Intervertebral disc cells produce tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 immediately after herniation: an experimental study using a new hernia model.

STUDY DESIGN: A new hernia model that simulates human disc herniations was developed in rabbits. The herniated discs were examined by gross appearance and histology and production of tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 was investigated. OBJECTIVES: To clarify the early mechanism of spontaneous herniated disc resorption. SUMMARY OF BACKGROUND DATA: Macrophage infiltration in herniated discs is essential for disc resorption. However, surgically removed human herniated disc tissues and existing animal hernia models are not suitable for analyzing the mechanism of macrophage infiltration. Recently, we have demonstrated that intervertebral disc cells are capable of producing monocyte chemoattractant protein-1, a potent macrophage chemoattractant, after stimulation with tumor necrosis factor alpha and interleukin-1beta. METHODS: Intervertebral disc herniations were surgically developed in rabbits using a new technique. The herniated discs were excised at appropriate time intervals after the surgery, and the size and histologic findings were examined. Expressions of tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 in herniated discs were investigated immunohistochemically. RESULTS: A new rabbit model of disc herniation was established. The herniated discs spontaneously reduced in size by 12 weeks postsurgery. Infiltrating cells, mainly composed of macrophages, were observed from day 3. Immunohistochemically, intervertebral disc cells in the herniated discs produced tumor necrosis factor alpha and interleukin-1beta on day 1, followed by monocyte chemoattractant protein-1 on day 3. CONCLUSIONS: The new hernia model appears to be very useful for studying herniated disc resorption. Intervertebral disc cells may produce inflammatory cytokines/chemokine immediately after the onset of disc herniation, possibly triggering subsequent macrophage infiltration that leads to disc resorption.

Postoperative spondylodiscitis from Aspergillus fumigatus in immunocompetent subjects.

The authors describe a case of spondylodiscitis from Aspergillus fumigatus which occurred subsequent to surgery for lumbar disc herniation in a non-immunodepressed patient. The results obtained by combined medical and surgical treatment are discussed.

Spondylodiscitis due to Clostridium ramosum infection in an immunocompetent elderly patient.

The first ever case of spondylodiscitis caused by Clostridium ramosum in an elderly immunocompetent patient has been reported. C. ramosum is usually an intestinal bacterium but may occasionally be isolated in clinical specimens as an opportunistic pathogen. This report shows that this anaerobic organism can cause bone tropism without there having been any contamination due to spinal surgery. The infection cleared after empirical therapy using intravenous amoxicillin and oral metronidazole.