Comparison of characteristics of culture-negative pyogenic spondylitis and tuberculous spondylitis: a retrospective study

Risk Factors Preventing Identification of the Microorganism Causing Vertebral Osteomyelitis

STUDY DESIGN

Retrospective study.

OBJECTIVE

To elucidate the factors influencing the identification of causative microorganisms in vertebral osteomyelitis (VO) and the effectiveness of different culture methods in increasing the identification rate.

METHODS

A total of 252 patients diagnosed with and treated for VO at a single hospital were enrolled. The results of various culture methods were reviewed along with the clinical data of the patients retrospectively.

RESULTS

Microbiological diagnosis was achieved in 210 out of 252 patients (83.3%). Diagnostic percentages of blood cultures, CT-guided drainage, fluoroscopic disc biopsy, and intraoperative specimens were 73.6%, 73.9%, 27.6%, and 50.8%, respectively. Staphylococcus aureus was the most common pathogen (85 cases, 40.5%). Higher White Blood Cell (WBC) count, lower serum albumin (ALB) level, epidural abscess, and absence of prior antibiotic exposure were significant predictors of positive culture results across all culture methods. Prior antibiotic exposure was the most significant predictor of negative outcomes (OR 0.24). Blood culture results correlated with body temperature, C-reactive protein (CRP), ALB, and prior antibiotic exposure. A shorter duration of antibiotic administration before culture was associated with an increased likelihood of positive blood culture results.

CONCLUSIONS

This study demonstrated that laboratory findings indicating a high inflammatory response (elevated WBC count, CRP level, and body temperature), lower ALB level, presence of epidural abscess, absence of prior antibiotic exposure, and shorter duration of antibiotics were significant predictors of positive culture results. Blood cultures should be conducted in the presence of high inflammation levels to improve microorganism identification rates.

Culture-Negative Native Vertebral Osteomyelitis: A Narrative Review of an Underdescribed Condition

The incidence of culture-negative NVO (CN-NVO) cases is increasing, presenting significant diagnostic and therapeutic challenges due to the inability to isolate causative organisms with conventional microbiological methods. Factors influencing the diagnosis of CN-NVO include prior antimicrobial therapy, low pathogen burden, fastidious or intracellular organisms, technical issues, and non-infectious mimickers. Diagnosis often relies on imaging modalities like magnetic resonance imaging (MRI) and computed tomography (CT)-guided biopsy, though these methods can sometimes fail to yield positive microbiological results. Advanced diagnostic tools, such as polymerase chain reaction (PCR), metagenomic next-generation sequencing (mNGS), and cell-free DNA analysis, may be necessary to identify the pathogen. The causative pathogen cannot be isolated in some patients, among which an empirical antimicrobial therapy should be initiated. This narrative review discusses the management, monitoring, surgical indications, and outcomes for patients with CN-NVO.

Aspergilloma Superinfection in the Spinal Canal of an 18-Year-Old Man: A Case Report

CASE

An 18-year-old immunocompetent man presented with symptomatic lumbar canal stenosis, discharging sinuses, and cold abscess for 3 years treated with multiple incision drainage procedures with cottonoid packing antibiotic therapy. Radiographic imaging showed a soft tissue mass in the canal causing bony destruction. Postoperative histopathological examination showed an Aspergillus fungal ball. Patient showed improvement at 6-month follow-up with medical management.

CONCLUSION

As far as we know, this is the first case report showing an aspergilloma involving the vertebral column. Inadequate antibiotic treatment and blind introduction of a foreign body into sinus tracts can lead to fungal infections mimicking tuberculosis, causing disastrous outcomes. Fungal cultures are recommended routinely.

Culture-negative versus culture-positive in pyogenic spondylitis and analysis of risk factors for relapse

OBJECTIVES

This study aims to compare and analyze the clinical features, diagnosis, treatment and prognosis of culture-negative and culture-positive primary pyogenic spondylitis.

METHODS

In a retrospective analysis, 202 cases of adult primary pyogenic spondylitis with complete clinical data in our hospital from January 2013 to January 2020 were divided into two groups according to bacterial culture results: culture negative (n = 126) and culture positive (n = 76). We compare the clinical characteristics, diagnosis, treatment and prognosis of patients with different culture results.

RESULTS

The culture positive rate was 37.62% (76/202). There were no significant differences in age, gender, affected segment, spinal abscess, diabetes mellitus, course of disease, surgery, recurrence, and follow-up time between the two groups (p>.05). There were statistically significant differences in hospital admission erythrocyte sedimentation rate (ESR), admission C-reactive protein (CRP), admission white blood cell (WBC) count, discharge ESR, discharge CRP, ESR decline rate, CRP (p<.05). There were statistically significant differences in the rate of decline, hospitalization days, and body temperature ≥38 °C (p<.05). Higher CRP levels on admission, antibiotic treatment time <6 weeks, and body temperature ≥ 38 °C are independent risk factors for infection recurrence.

CONCLUSIONS

The culture-negative group's admission WBC, admission ESR, admission CRP, discharge ESR, discharge CRP, ESR decline rate, CRP decline rate, and hospital stay were lower than the culture positive group, the difference was statistically significant (p<.05). The independent risk factors for infection recurrence are higher CRP levels in hospital admission, antibiotic treatment time <6 weeks, and body temperature ≥ 38 °C.

Spinal infection caused by Coxiella burnetii

BACKGROUND

Spinal infection caused by Coxiella burnetii is rare and difficult to diagnose. Here we reported a case of spinal infection from Coxiella burnetii detected by the metagenomic next-generation sequencing (mNGS).

CASE PRESENTATION

A 66-year-old male farmer with no medical history reported severe sharp low back pain, numbness and lower limb weakness for three years. Magnetic resonance imaging (MRI) revealed bone destruction and spinal cord compression within L1 and L2. mNGS testing showed that the inspected specimen collected from spinal lesion was detected positively for Coxiella burnetii. After receiving the combined treatment of antibiotic therapy and surgical intervention, the patient recovered well, and the sagittal MRI showed that vertebral edema signals disappeared and the graft of bone fused 16 months after surgery.

CONCLUSION

The mNGS may be benefit for early diagnosis and intervention of non-specific spinal infection, and future studies should validate its effectiveness for clinical use in spinal infections. Additionally, antibiotic therapy combined with surgical intervention plays an important role on the treatment of spinal infection caused by Coxiella burnetii.

Surgery combined with antibiotics for thoracic vertebral Escherichia coli infection after acupuncture: A case report

BACKGROUND

Acupuncture is relatively popular worldwide, but an unregulated operation can easily lead to infections. The purpose of this report was to analyze a clinical case of surgery combined with the use of antibiotics for the treatment of thoracic vertebral infection by Escherichia coli (E. coli) after acupuncture.

CASE SUMMARY

A 63-year-old male was diagnosed with E. coli infection in the thoracic vertebra after acupuncture. His fever and pain did not improve after treatment with broad-spectrum antibiotics for 10 d. Thus, debridement of the infected area and biopsy were decided. The final pathology confirmed the diagnosis of vertebral infection by E. coli. The patient underwent anterior and posterior thoracic vertebral debridement and internal fixation surgery combined with the use of sensitive antibiotics. He had no fever or backache 3 mo postoperatively.

CONCLUSION

In this report, we first considered antibiotic treatment for the patient with septic spinal infection, but the effect was not obvious. Interventional surgery was combined with the use of sensitive antibiotics to relieve backache, and good clinical results were achieved. Furthermore, acupuncture practitioners should pay attention to hygienic measures.

Influence of microbiological diagnosis on the clinical course of spondylodiscitis

PURPOSE

This study sought to recognize differences in clinical disease manifestations of spondylodiscitis depending on the causative bacterial species.

METHODS

We performed an evaluation of all spondylodiscitis cases in our clinic from 2013-2018. 211 patients were included, in whom a causative bacterial pathogen was identified in 80.6% (170/211). We collected the following data; disease complications, comorbidities, laboratory parameters, abscess occurrence, localization of the infection (cervical, thoracic, lumbar, disseminated), length of hospital stay and 30-day mortality rates depending on the causative bacterial species. Differences between bacterial detection in blood culture and intraoperative samples were also recorded.

RESULTS

The detection rate of bacterial pathogens through intraoperative sampling was 66.3% and could be increased by the results of the blood cultures to a total of 80.6% (n = 170/211). S. aureus was the most frequently detected pathogen in blood culture and intraoperative specimens and and was isolated in a higher percentage cervically than in other locations of the spine. Bacteremic S. aureus infections were associated with an increased mortality (31.4% vs. overall mortality of 13.7%, p = 0.001), more frequently developing complications, such as shock, pneumonia, and myocardial infarction. Comorbidities, abscesses, length of stay, sex, and laboratory parameters all showed no differences depending on the bacterial species.

CONCLUSION

Blood culture significantly improved the diagnostic yield, thus underscoring the need for a structured diagnostic approach. MSSA spondylodiscitis was associated with increased mortality and a higher incidence of complications.

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.

Microbiologic Diagnosis of Pyogenic Spondylitis

Pyogenic spondylitis requires long-term antibiotics treatment and identification of the etiologic microorganism is essential. The first test in the microbiologic diagnosis of pyogenic spondylitis is a blood culture. Any microorganisms that grow in blood culture are highly likely to be the etiological microorganisms of pyogenic spondylitis. If the microbial etiology cannot be defined by the blood culture, a needle biopsy is performed on the inflamed tissues. Here, it is recommended that paraspinal tissues, rather than spinal tissues, are collected to increase the positive rate in tissue culture. If the microbial etiology cannot be defined by the first needle biopsy, another needle biopsy may be performed. The collected tissue sample is used in culture tests on bacteria and mycobacteria as well as pathological tests. If tuberculous spondylitis is suspected, polymerase chain reaction is carried out to detect Mycobacterium tuberculosis. In the case that the etiological microorganisms cannot be identified, the data of the patient regarding age, sex, vertebrae involved, history of spinal surgery or procedure, previous or concurrent urinary tract or intra-abdominal infection are analyzed. Based on this the most probable microbial etiology is determined to select the antibiotics to be used in the empiric treatment.

Change of Pyogenic and Tuberculous Spondylitis between 2007 and 2016 Year : A Nationwide Study

Objective

We attempted to compare the incidence of pyogenic spondylitis (PS) and tuberculous spondylitis (TS) between 2007 and 2016. Furthermore, we investigated the patients who underwent surgery in 2016 compared to that in 2007.

Methods

We used a nationwide database managed by the Korean National Health Insurance Service (NHIS) in 2007 and 2016. Total 9655 patients with a newly diagnosis of PS or TS were enrolled in PS or TS group. Among them, 1721 patients underwent either fusion or decompression surgery. We analyzed demographic distribution of patients according to gender and age and year of diagnosis.

Results

Comparing between 2007 and 2016, the incidence of PS has increased in 2016 than in 2007 (4874 vs. 2431, p<0.0001). Conversely, declination of incidence of TS was discovered in 2016 compared to 2007 (594 vs. 1756, p<0.0001). Females showed predominance over males regarding both PS and TS (5228 vs. 4427, p<0.0001). Among them, the number of PS patients who underwent surgery increased significantly in 2016 relative to that in 2007 (979 vs. 592, p<0.0001).

Conclusion

This nationwide study suggests that PS may increase and TS may decrease in Korea. In addition, demand for surgery regarding PS may increase.

The Value of Histology in the Diagnosis of Tuberculous Spondylodiscitis

BACKGROUND

Tuberculous spondylodiscitis (TS) is the most common form of musculoskeletal tuberculosis. Currently, histology is widely used to distinguish tuberculous from nontuberculous disease.

OBJECTIVES

The aim of the present study was to assess the accuracy of histology compared with bacteriology in the diagnosis of TS.

METHODS

This is a single-center case series carried out from January 2014 to February 2018 in a pathology department. It included 121 discovertebral biopsies of infective spondylodiscitis. The measures of diagnostic accuracy of histology were determined taking bacteriology as criterion standard.

RESULTS

Among the 121 cases, 55 (45.4%) were diagnosed as TS by histological and/or bacteriological findings, 17 (30.9%) were classified as definite TS by bacteriology, and the remaining 38 (69.1%) had positive histology and negative bacteriology. There were 2 false-negatives, which histologically displayed suppuration without granuloma, and 3 false-positives; in one case, histology displayed granulomas without necrosis and culture isolated Brucella. In the 2 others, histology revealed granulomas with caseous-like necrosis and microbiology isolated fungal species. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of histology in the diagnosis of TS were 88.2%, 93.4%, 83.3%, 95.5%, and 92%, respectively.

CONCLUSIONS

Histology is proved to be an accurate diagnostic tool in TS. Suppurative forms of TS without granuloma are rare and represent the main cause of false-negative histology. Suggestive histology of TS does not rule out fungal and brucellar spondylodiscitis. Caseous necrosis is not pathognomonic of tuberculosis. Fungal infection can also exhibit such type of necrosis.

Transforaminal Lumbar Interbody Fusion with Antibiotics Delivered by CaSO4 Drug Carrier System for Pyogenic Spondylodiscitis

BACKGROUND

Spondylodiscitis is a challenging spinal disorder that requires surgical treatment only as a last resort. The use of various procedures and instruments remains controversial. In this retrospective study, we reported the safety and efficacy of a CaSO₄ drug carrier system for the transforaminal lumbar interbody fusion (TLIF) procedure for lumbar pyogenic spondylodiscitis.

METHODS

Thirty-four patients with lumbar spondylodiscitis underwent TLIF. CaSO₄ beads carrying vancomycin and gentamycin were implanted in the trajectory of screws and disc spaces. We measured markers of inflammation, scores of neurologic recovery, and quality of life. The fusion status was assessed at final follow-up and the correction of local and total lordotic angle was calculated.

RESULTS

The patients were followed up for at least 12 months (range, 12-24 months). At 3 months follow-up, C-reactive protein levels and erythrocyte sedimentation rate returned to normal with no relapse. Nineteen patients with American Spinal Injury Association grade D preoperatively returned to American Spinal Injury Association grade E. The improvement on the visual analog scale and Oswestry Disability Index was 66.9% and 84.9%, respectively. At 12 months follow-up, 67.6% of patients achieved definitive union. The corrections of total and local lordotic angle were 10.02° ± 8.77° and 7.7° ± 8.75°, respectively. The rate of achievement of satisfactory Kirkaldy-Willis functional criteria was 85.3%.

CONCLUSIONS

The combined use of single-level TLIF with a CaSO₄ drug delivery system was safe and effective for treatment of pyogenic lumbar spondylodiscitis. The system promoted reduction of inflammation with limited fixed segments without a negative impact on fusion status. This procedure may be considered a novel choice for spondylodiscitis, with more efficacy and less invasion.

Diagnostic usefulness of the QuantiFERON-TB gold in-tube test (QFT-GIT) for tuberculous vertebral osteomyelitis

BACKGROUND

Interferon (IFN)-γ-releasing assay for diagnosing tuberculosis (TB) has shown promise; however, there are only a few reports on usefulness of the QuantiFERON-TB Gold In-Tube test (QFT-GIT) for diagnosing TB vertebral osteomyelitis.

METHODS

All patients presenting at a tertiary hospital between January 2010 and July 2016 with suspected TB vertebral osteomyelitis were retrospectively enrolled to evaluate the diagnostic performance of QFT-GIT. We used QFT-GIT to measure the IFN-γ response to ESAT-6, CFP-10 and TB7.7.

RESULTS

A total of 141 patients were enrolled; 32 (23%) were categorized as having confirmed TB, (1%) as probable TB, 14 (10%) as possible TB and 93 (66%) as not TB. Of these, 16 patients with probable and possible TB were excluded from the final analysis. Chronic granulomas with/without necrosis, acid-fast bacilli stain, M. tuberculosis polymerase chain reaction and cultures for M. tuberculosis were positive in 14 (44%), 12 (38%), 22 (69%) and 28 (88%) patients, respectively, among the 32 patients with confirmed TB. The overall sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratio for a positive result, and likelihood ratio for a negative result of the QFT-GIT for TB vertebral osteomyelitis were 91% (95% confidence interval [CI], 75-98%), 65% (95% CI, 54-75%), 50% (95% CI, 42-58%), 95% (95% CI, 86-98%), 2.59 (95% CI, 1.89-3.55) and 0.14 (95% CI, 0.05-0.43), respectively.

CONCLUSION

The QFT-GIT appears to be a useful adjunct test for diagnosing TB vertebral osteomyelitis because the negative test results may be useful for excluding a diagnosis of active TB vertebral osteomyelitis.