Abstract
Objective
To establish a unified tuberculosis staging system for trunk and limbs joints (Osteoarticular tuberculosis At Qinghai Fourth People’s Hospital, QFOT), and verify the rationality and applicability of the classification system.
Method
Searching our hospital’s electronic medical record database from 2019 to 2022, including data of patients with bone and joint tuberculosis according to preset inclusion and exclusion criteria, and formulating a bone and joint tuberculosis staging system of the Fourth People’s Hospital of Qinghai Province based on imaging data related to bone collapse, abscess flow metastasis, mechanical axis deviations, stable bone structure, joint deformity and other characteristics. Then, gender distribution, age distribution, whether surgery, pre-operation anti-tuberculosis drug treatment courses, white blood cell count, RBC sedimentation rate, C-reactive protein and serum procalcitonin were analyzed statistically. Understand the characteristics of Osteoarticular tuberculosis cases in different stages and verify the rationality of the QFOT staging system.
Results
A total of 16,487 tuberculosis patients were admitted to our hospital from 2019 to 2022, and a total of 509 patients with Osteoarticular tuberculosis were finally included, aged 41.1 ± 16.39 years. According to the QFOT staging system, 202 patients with stage I tuberculosis, 164 patients with stage II tuberculosis, 107 patients with stage III tuberculosis, 29 patients with stage IV tuberculosis, and 1 patient with stage V tuberculosis were classified. There were no significant differences in gender and age distribution of patients in different stages. There is a significant difference in the distribution of whether or not anti-tuberculosis drugs were used before surgery. There was no significant difference in white blood cell count levels among patients with different stages of Osteoarticular tuberculosis, and there were significant differences in red blood cell sedimentation rate and C-reactive protein levels. There are significant differences in the distribution of serum procalcitonin in patients with different stages of Osteoarticular tuberculosis.
Conclusion
The QFOT staging system stages according to the pathological process of bone and joint tuberculosis. The verification results found that the QFOT staging system is scientific, but due to the small number of stage V patients included, further research is still needed to verify and improve this typing method.
Clinical trial number
Not applicable.
Keywords: Tuberculosis, Staging system of Osteoarticular tuberculosis, Validation, Retrospective study
Introduction
Tuberculosis (TB) is a preventable and usually curable disease. Yet in 2023, TB probably returned to being the world’s leading cause of death from a single infectious.
agent, following 3 years in which it was replaced by coronavirus disease (COVID-19), and caused almost twice as many deaths as HIV/AIDS. More than 10 million people continue to fall ill with TB every year and the number has been rising since 2021. Urgent action is required to end the global TB epidemic by 2030 [1].
Tuberculosis has diverse manifestations and is divided into pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) based on clinical manifestations. EPTB is defined as tuberculosis of organs other than the lungs (such as the pleura, lymph nodes, abdomen, urogenital tract, skin, joints and bones or meningeal). In a study in South Korea, extrapulmonary tuberculosis (EPTB) accounted for about 20% of all tuberculosis (TB) [2]. The average incidence of EPTB in India is approximately 15–20%, depending on the HIV status of the cohort [3, 4].
A 2015 UK study found that osteoarticular tuberculosis (OATB) accounted for 6.7% of total tuberculosis cases in the UK and 14.4% of extrapulmonary tuberculosis cases [5]. Most tuberculosis of bones and joints is secondary to pulmonary tuberculosis or tuberculosis in other parts (such as lymph nodes, intestines). Tuberculosis bacteria spread to bones or joints through blood (blood-borne transmission), and a few spread directly from adjacent tuberculosis lesions. Most diffuse lesions are eliminated by phagocytes, and very few diffuse lesions are dormant early. Once the body’s resistance declines, latent infection of tuberculosis will reproduce and break through surrounding tissues to develop into a disease. The incidence of OATB in EPTB is second only to lymphatic tuberculosis. It mainly affects large load-bearing joints such as hands, feet, spine, hips, and knees, and is manifested as joint pain, deformation and even disability, which seriously affects the patient’s quality of life [6].
However, the incidence, severity and treatment of osteoarticular tuberculosis vary. In particular, there is no unified standard for typing, pathological typing, image typing of various parts, and typing based on strain genotypes, resulting in a lack of consensus among clinicians on differences in the staging and clinical treatment of Osteoarticular tuberculosis [7–10]. The main purpose of this study is to retrospectively analyze and summarize the cases of osteoarticular tuberculosis in our hospital in the past three years, propose new criteria for the staging of bone and joint tuberculosis based on the patients ‘symptoms and imaging findings, and use the patients’ blood test indicators (such as C-reactive protein) to verify the rationality of the staging criteria. Provide reference for follow-up treatment of osteoarticular tuberculosis.
Materials and methods
Searching our hospital’s electronic medical record database from April 2019 to April 2022, a total of 16,487 tuberculosis patients were reported. All the above cases were diagnosed in our hospital. Screening was conducted according to pre-set inclusion and exclusion criteria.
Patients with osteoarticular tuberculosis were screened from tuberculosis patients according to the following screening criteria. The inclusion criteria for patients are as follows: (1) Diagnosis of tuberculosis: Patients need to be diagnosed with tuberculosis through bacteriology, pathology or imaging. (2) Symptoms of osteoarticular tuberculosis: Patients should show typical symptoms of Osteoarticular tuberculosis, such as local pain, swelling, limited movement, etc. (3) Imaging evidence: X-ray, CT or MRI showed Osteoarticular tuberculosis characteristics such as bone destruction and vertebral collapse. (4) Laboratory tests: positive tuberculin test (TST) or interferon gamma release test (IGRT), or detection of MTB DNA by PCR. Exclusion criteria: (1) Non-tuberculous bone disease: Eliminate bone disease caused by other causes, such as tumors, osteomyelitis, etc. (2) Serious complications: Patients with severe cardiac, hepatic and renal dysfunction or immune system diseases were excluded. (3) Pregnancy or lactation: Women who are pregnant or breastfeeding are usually excluded. (4) Unable to cooperate with follow-up: Patients who cannot complete follow-up or treatment as required are excluded. Since our hospital is an infectious disease hospital in Qinghai Province of China and belongs to a regional central hospital, some patients often experience general tuberculosis symptoms or bone disease symptoms and are referred to our hospital for further treatment. Therefore, the time between the appearance of general tuberculosis symptoms or bone disease symptoms and diagnosis cannot be accurately obtained.
Finally, 509 cases of osteoarticular tuberculosis were included. This is also in line with the results of an epidemiological study conducted in Greece, where the proportion of bone and joint tuberculosis among tuberculosis patients is relatively low [11]. Four experienced orthopedic surgeons first conducted a comprehensive review of the above cases and classified osteoarticular tuberculosis based on the location of Osteoarticular tuberculosis lesions, whether there were bone collapse, abscess and exudative metastasis, intensity line changes, mechanical axis deviations, stable bone structure, joint deformity, etc. Combined imaging findings. It was divided into stages I-V, and then a meeting was held to discuss and improve this staging standard, and finally a new unified staging system for tuberculosis in the trunk and limbs was developed: (Osteoarticular Tuberculosis At Qinghai Fourth People’s Hospital, QFOT).Subsequently, 509 cases were classified according to the QFOT staging system, and the patients ‘preoperative medication status was collected.Patients in this region generally had low education levels, and this data only captured the patients’ medication duration. Finally, the rationality of the QFOT staging criterion was verified by statistical analysis of white blood cell count, red blood cell sedimentation rate, C-reactive protein, preoperative medication, and procalcitonin in patients with different stages of osteoarticular tuberculosis. As shown in Fig. 1.
Fig. 1.
Case Screening flow chart
Setting the stage of osteoarticular tuberculosis
Statistical analysis
Calculate the mean and standard deviation for continuous variables. Differences in proportions between groups were analyzed using a chi-square test, and continuous variables were subjected to t-test (normally distributed data) or Kruskal-Wallis test (non-normally distributed data).
Results
Population characteristics of patients with osteoarticular tuberculosis
As shown in Fig. 2, a total of 509 patients were included, the mean and standard deviation of age were 41.1 ± 16.39 years, and the quartiles were (Q1 = 27.00, Median = 37.00, Q3 = 54.00). Among them, 39 patients were < 20 years old, 98 patients were 21–30 years old, 90 patients were 31–40 years old, 112 patients were 41–50 years old, 105 patients were 51–60 years old, 38 patients were 61–70 years old, and 27 patients were >70 years old. 79.4% of the patients with osteoarticular tuberculosis in this study were between 21 and 60 years old. This finding is basically consistent with the extrapulmonary tuberculosis data published by Li Tao et al. (72% are 15–65 years old, 26% are over 65 years old) [12]. The gender distribution in this study was 276 males, accounting for 54%, and 233 females, accounting for 46%. This is slightly different from the results of Li Tao et al. (65.1% for men and 34.9% for women) [12].
Fig. 2.
Age distribution map of patients with Osteoarticular tuberculosis
Setting the stage of osteoarticular tuberculosis
Osteoarticular tuberculosis can be divided into stages Ⅰ to Ⅴ according to the stage of lesion development and imaging findings (Figs. 3, 4 and 5).
Fig. 3.
Staging diagram of stages I to V of spinal tuberculosis
Fig. 4.
Staging of stage I to V tuberculosis of the hip joint
Fig. 5.
Staging diagram of stage I to V tuberculosis in the knee joint
Stage I includes the inflammatory stage, simple bone or synovial soft tissue lesions, X-ray examination of joint space changes or normal conditions, and less pus production; X-rays sometimes fail to be diagnosed and need to be combined with CT and MRI examinations. In this stage, MRI examination reveals mainly bone edema and exudate.
Stage II: In the osteonecrosis and cystic change stage, all joints have osteonecrosis or cystic lesions, more pus is produced, but the scope is relatively limited, and the structural support of the bone is limited. Widening or narrowing of the joint space, bone changes on X-ray.
Stage III: In the diffusion stage, the pus of bone and joint lesions flows, which may produce cross-type bone and soft tissue lesions, including the possibility of infection of adjacent cavities or organs, including the formation of soft tissue sinuses, but the structural support of bone exists. When the joint space widens or narrows, X-ray can reveal adjacent or straddling joint lesions, which need to be combined with CT, MRI, ultrasound and laboratory examinations for comprehensive judgment.
Stage IV: In the collapse stage, regardless of whether abscess flow spreads through the lesion, the structural support or protective effect of the bone is destroyed, the joint alignment changes, and the trunk and limb mechanical axis deviations, bone structure unstable, resulting in malformation or dysfunction at the lesion site and loss of protection by bone protective tissue, such as nerve compression, but this problem can be corrected or partially corrected by surgery.
In Stage V, which includes the malformation and dislocation stages, there may be two or more stage IV lesions, more pus communicating branches and skin sinuses, serious malformation and dysfunction of the trunk limbs, more abscess calcification, joint dislocation deformity fusion, peripheral vascular and nerve compliance changes, reversal limitations, surgical treatment risk, and high failure rates.
Correlation analysis between different stages of osteoarticular tuberculosis and inflammatory indicators
According to statistics, there were 427 cases of spinal tuberculosis, 156 cases of joint tuberculosis and 10 other cases of Osteoarticular tuberculosis. There were 6 cases involving the cervical spine, 149 cases involving the thoracic spine, 228 cases involving the lumbar spine and 47 cases involving the sacral spine. Fifty-three cases of joint tuberculosis occurred in the knee joint, followed by 39 cases in the hip joint, 22 cases in the elbow joint, 21 cases in the ankle joint, 13 cases in the wrist joint and 8 cases in the shoulder joint. Other categories of statistics include muscle and soft tissue. The above data do not exclude the presence of multiple sites in the same patient.
Chi-square test was used to compare and analyze the basic characteristics of patients with Osteoarticular tuberculosis in different stages. The results found that there were no significant differences in the gender and age distribution of patients with Osteoarticular tuberculosis in different stages. There were significant differences in the proportion of patients with osteoarticular tuberculosis in different stages. There were also significant differences in the course of treatment used by patients with Osteoarticular tuberculosis in different stages. Support the clinical rule that the later the staging, the longer the preoperative treatment time. Here, the surgery we refer to refers to debridement + spinal fusion and internal fixation (or joint replacement). As shown in Table 1.
Table 1.
Patient characteristics and correlations with inflammatory indexes
| I(n = 202) | II(n = 164) | III(n = 107) | IV(n = 29) | V(n = 7) | x2/H | p value | ||
|---|---|---|---|---|---|---|---|---|
| Gender | Male | 107(53.0%) | 83(50.6%) | 62(57.9%) | 18(62.1%) | 6(85.7%) | 5.103 | 0.277 |
| Female | 95(47.0%) | 81(49.4%) | 45(42.1%) | 11(37.9%) | 1(14.3%) | |||
| Operation or not | unoperated | 182(90.1%) | 85(51.8%) | 40(68.1%) | 12(41.4%) | 5(71.4%) | 109.293 | 0.000 |
| Preoperative antitubercular therapy | <1 month | 12(70.6%) | 25(30.5%) | 2(3.0%) | 9(50.0%) | 1(20.0%) | 61.094 | 0.000 |
| 1–2 month | 0(0.0%) | 18(22.0%) | 19(28.4%) | 5(27.8%) | 0(0%) | |||
| 2–3 month | 2(11.8%) | 9(11.0%) | 12(17.9%) | 2(11.1%) | 0(0%) | |||
| 3–6 month | 2(11.8%) | 18(22.0%) | 24(35.8%) | 0(0.0%) | 2(40.0%) | |||
| 6–12 month | 1(5.9%) | 8(9.8%) | 5(7.5%) | 1(5.6%) | 0(6.9%) | |||
| >12 month | 0(0%) | 4(4.9%) | 5(7.5%) | 1(5.6%) | 2(40.0%) | |||
| Year | ≤ 20years | 22(10.9%) | 11(6.7%) | 4(3.7%) | 1(3.4%) | 1(14.3%) | 19.455 | 0.078 |
| 21-40years | 84(41.6%) | 51(31.1%) | 40(37.4%) | 13(44.8%) | 0(0%) | |||
| 41-60years | 72(35.6%) | 78(47.6%) | 52(48.6%) | 10(34.5%) | 5(71.4%) | |||
| >60years | 24(11.9%) | 24(14.6%) | 11(10.3%) | 5(17.2%) | 1(14.3%) | |||
| White blood cell count | *109/L | 5.56(5.29–5.83) | 5.83(5.47–6.18) | 5.99(5.62–6.36) | 6.16(5.35–6.98) | 4.78(3.01–6.54) | 7.776 | 0.100 |
| Erythrocyte sedimentation rate | mm/H | 20.47(17.60-23.34) | 27.44(24.05–30.83) | 30.42(25.41–35.44) | 28.29(20.32–36.25) | 30.14(3.19–57.09) | 21.917 | 0.000 |
| C-reactive protein | mg/L | 22.01(17.45–26.57) | 28.62(22.67–34.58) | 43.10(34.94–51.26) | 40.54(25.34–55.74) | 38.34(-9.12-85.80) | 35.864 | 0.000 |
| Serum procalcitonin (ng/L) | <0.05 | 90(68.2%) | 56(52.3%) | 26(41.9%) | 7(58.3%) | 3(60%) | 13.462 | 0.009 |
| >0.05 | 42(31.8%) | 51(47.7%) | 36(58.1%) | 5(41.7%) | 2(40%) |
x2: chi-square test, H: Kruskal-Wallis test
Normal test was performed on the white blood cell count, red blood cell sedimentation rate and C-reactive protein level of the included patients, and it was found that all three groups of data were non-normal distribution. Therefore, the H test (Kruskal-Wallis) was used to compare and analyze the white blood cell count, red blood cell sedimentation rate and C-reactive protein level of patients with osteoarticular tuberculosis in different stages. The test indicators were all the results of the first hospitalization. The results showed that there was no significant difference in white blood cell counts among patients with different stages of osteoarticular tuberculosis, but there were significant differences in red blood cell sedimentation rate and C-reactive protein levels (p < 0.05). The erythrocyte sedimentation rate (ESR) of patients in stages III, IV, and V was significantly higher than that of patients in other stages, and the average level of ESR basically increased significantly with the increase of stage. The C-reactive protein levels in stage III and IV patients are similar, but the C-reactive protein levels in stage V patients are slightly lower than those in stage III and IV patients, and significantly higher than those in stage I and II patients. Similarly, as tuberculosis patients ‘condition worsens, C-reactive protein increases significantly.
Among the 509 patients with osteoarticular tuberculosis, 313 patients received serum procalcitonin testing before surgery. Chi-square test was used to analyze the distribution of serum procalcitonin test results among different stages of osteoarticular tuberculosis. The results showed that there were significant differences in the distribution of serum procalcitonin in different stages of osteoarticular tuberculosis (P < 0.005).
Discussion
Previous studies on the staging of osteoarticular tuberculosis
Currently reported staging methods for spinal tuberculosis are as follows. In 1993, Jain et al.9. classified spinal tuberculosis into different types according to the different manifestations of the degree of destruction of spinal tuberculosis foci on CT. Type I: fragmentation type; Type II: osteolytic type; Type III: subperiosteal type; Type IV: focal hardening type. Fragmentation is the most common type, accounting for 47% of the total. This classification is based on CT imaging and describes the degree of vertebral destruction in detail, which has certain significance in the diagnosis and differentiation of spinal tuberculosis. However, this classification relies only on CT for the observation of spinal tuberculosis, which has some limitations in revealing changes in the vertebral space and surrounding soft tissue. This classification does not provide specific guidance for clinicians in terms of treatment. In 2008, Oguz et al.8 proposed a GATA classification method for spinal tuberculosis. The study included 76 patients with spinal tuberculosis, and the following seven classification criteria were proposed: abscess formation, disc damage, vertebral body destruction, spinal stability, kyphotic deformity, sagittal plane index, and impaired nerve function. According to the above criteria, spinal tuberculosis can be divided into three types, and the treatment of each type is indicated. However, the applicability of this classification to skip tuberculosis and multisegmental spinal tuberculosis is not known, and the clinical application of this classification is controversial. For example, according to the GATA classification criteria, for patients with spinal tuberculosis, if the degree of vertebral body destruction is > 1/2, there is no obvious kyphosis, and if the sagittal plane index is < 20°, distinguishing between type II and type III cases is difficult. This is because the degree of kyphosis varies greatly from individual to individual, so it has certain limitations in guiding the clinical assessment of spinal stability. In 2011, Zhang Zhongmin et al.7 proposed the classification of spinal tuberculosis on the basis of MRI findings. This classification is only detailed on MR images; however, if the vertebral body is not destroyed more than 1/3 of the time, dead bone, abscess and even granuloma may exert pressure on the nerve root or spinal cord, and it is difficult to classify it as type II or type IV. The occupation of abscesses often does not require spinal canal decompression treatment, and the pressure can be relieved with the removal of the lesion. Moreover, it is easy to miss and misdiagnose, such as when hyperplasia, dead bone and calcification lesions are not easily distinguished, etc. Although the classification is not described, it has reference significance for the selection of surgical methods. This classification system is more detailed and reasonable than the previous classification system is, but it has the disadvantage of being difficult to remember and compare.
There are relatively few published studies on the classification of joint tuberculosis. According to the study of Babhulkar et al.10, hip joint tuberculosis can be divided into four types: synovitis, early arthritic, arthritic and late arthritic. However, the clinical manifestations of this subtype are varied and difficult to distinguish. In imaging, the early stage of arthritis is not easily distinguished from the other stages of arthritis, such as the formation of fragments of the femoral head or acetabulum, which involve the articular surface but have normal integrity and space. Subcephalic necrosis of the femoral head, although not involving the articular surface, cannot be explained by early arthritic manifestations, and treatment modalities differ.
For the classification of tuberculosis of the knee joint, no relevant literature was found, but the development process of the disease is the same as that of the hip joint, which is still from synovial lesions to joint malformations and dislocations. With the increasing number of modern treatment methods, classification and distinction are necessary to facilitate statistical analysis and guide treatment.
Pulmonary tuberculosis and osteoarticular tuberculosis
In this study, no systematic assessment including lung lesions was performed. This is because an existing review found that 16.55% of patients with multiple osteoarticular tuberculosis had pulmonary tuberculosis [13], an epidemiological study in India found that 40% of the included OATB patients also had pulmonary tuberculosis [14], and an epidemiological study in Hunan, China found that OATB and pulmonary tuberculosis accounted for 23.4% of the included population [6]. This suggests that not all OATB patients will have lung lesions. In addition, since this study is a retrospective study, we did not perform systematic imaging evaluation (such as standardized chest CT) on all patients to rule out concurrent lung involvement. The presence of subclinical lung lesions may contribute to the systemic inflammatory response, thereby affecting marker levels. Although this means that we cannot clearly distinguish between the contributions of systemic and local bones and joints to inflammation, and there are certain limitations, it also shows that our preset staging system captures patients with more severe systemic disease burden, which also has its clinical significance.
Relationship between preoperative anti-tuberculosis course and different stages of bone tuberculosis
The results of the study found that men often account for a large proportion of stage IV and V bone and joint tuberculosis. This may be due to the fact that the number of cases of stage I and V bone and joint tuberculosis in this study was generally low, which may affect the distribution of different genders. In addition, it may also be that men themselves are a risk factor for developing higher-stage bone and joint tuberculosis, which is similar to the results of a study in Ethiopia [15]. Their results found that men have a higher risk of developing drug-resistant tuberculosis. There are many views on the treatment of hip tuberculosis that anti-tuberculosis treatment should start before surgery and that anti-tuberculosis treatment needs to be continued after surgery [16, 17]. Some research reports indicate that anti-tuberculosis treatment should be given for at least 2 weeks before surgery [16], while some scholars have found that anti-tuberculosis treatment should be given for 3–6 months before surgery [18]. In addition, some researchers believe that effective preoperative anti-tuberculosis treatment should be based on the clinical manifestations of the disease and radiological progress. Elderly patients with crippling tuberculosis of the hip joint and radiographic signs of arthritis can have early surgery after at least two weeks of ATT [19]. The results of this study showed that 70.6% of patients with stage I osteoarticular tuberculosis only needed less than 1 month of preoperative anti-tuberculosis treatment (consistent with the principle of early rapid surgery). More than 60% of patients with stage III osteoarticular tuberculosis require anti-tuberculosis treatment for more than 2 months (28.4% for 1–2 months, 35.8% for 3–6 months), reflecting that progressive lesions require extended control. This research result is basically in line with the views of other researchers. In the bone tuberculosis staging system established in this study, stage IV bone and joint tuberculosis is classified as advanced, but the study results show that 50% of patients have preoperative anti-tuberculosis treatment for less than 1 month. This may be because the patient requires emergency surgery to alleviate the progression of the disease (such as the patient’s spinal instability and the risk of paralysis), or it may be that the patient’s failure to seek medical treatment in time delayed the disease.
Relationship between red blood cell sedimentation rate and osteoarticular tuberculosis stage
ESR is a sensitive marker of the inflammatory response and is part of a well-established routine investigation for TB. A previous research showed that compared to healthy controls, ESR values were significantly increased in tuberculosis patients. To measure ESR is a simple and cost-effective method to predict TB [20]. Studies have shown that MMP-2, MMP-9 and MMP-13 in the matrix metalloproteinase (MMP) family play a crucial role in intervertebral disc destruction caused by spinal cord infection. The differential expression of MMPs may be one of the reasons for the different degree of intervertebral disc destruction in different types of spinal cord infections. However, when the clinical indicators such as CRP, ESR, IL-6, WBC and NEUT are increased, the expression of MMP-13 in the intervertebral disc at the lesion site is significantly increased [21]. In addition, Mantu Jain et al. found a positive correlation between plasma levels of ESR and CRP and multi-level vertebral involvement [22]. Overall, ESR is a useful but non-specific indicator of Osteoarticular tuberculosis, and higher levels are often associated with more advanced or active disease. In this study, it has certain scientific nature as a verification indicator for different stages of Osteoarticular tuberculosis.
Relationship between C-reactive protein and osteoarticular tuberculosis stage
On the basis of the joint pathological manifestations of tuberculosis and the development process of basic similarity, we propose that the combination of the trunk and limbs should be applied in the instalment QFOT (osteoarticular tuberculosis at Qinghai Fourth People’ head). The rationality and applicability of this stage are discussed. Stage Ⅰ: inflammatory stage; Stage II: osteonecrosis and cystic change stage; Stage III: diffusion stage; Stage IV: collapse stage; Stage V: malformation and dislocation stage. This retrospective analysis showed that serum C-reactive protein levels were significantly different in different stages of osteoarticular tuberculosis, verifying the rationality of the occurrence and stage of inflammation. Many institutions have studied the diagnosis of C-reactive protein in tuberculosis patients and the relationship between C-reactive protein and the prognosis of tuberculosis patients [23–26]. C-reactive protein can be used to screen for active tuberculosis, and high C-reactive protein levels and poor physical condition are associated with non-negative sputum smears, which justifies the use of C-reactive protein as a staging test for osteoarticular tuberculosis.
Relationship between serum procalcitonin and osteoarticular tuberculosis stage
Previous studies on PCT levels in tuberculosis patients were small, and the results varied greatly. A study by Rasmussen et al. found that PCT levels in patients with tuberculosis were significantly higher than in healthy people. In addition [27], Ugajin et al. found that the average PCT level in tuberculosis patients was 102ng/mL [28]. However, Huang et al. found that the PCT level in tuberculosis patients was 0. ng/mL [29]. Another meta-analysis found that the PCT cut-off for tuberculosis patients was between 0.10 and 0.25 ng/mL. In summary, PCT levels in patients with tuberculosis increased only slightly [30]. In this study, there were significant differences in the distribution of procalcin results in different stages of Osteoarticular tuberculosis. However, judging from the results, only patients with osteoarticular tuberculosis with QFOT stage III have a large proportion of pct >0.05. Therefore, using PCT to verify different stages of osteoarticular tuberculosis is not convincing. This may be related to the small number of patients with osteoarticular tuberculosis in stage IV and V, with a smaller sample size leading to data instability and we need further research.
Conclusion
The QFOT staging system delineates the pathological progression of bone and joint tuberculosis. A distinctive feature of this approach is that it does not rely on specific quantitative indicators such as angles or indices, but instead utilizes whole-body multi-joint imaging. The introduction of this staging system has provided novel concepts and methodologies for the management of bone and joint tuberculosis. It offers clinicians a more intuitive framework for classification, enhances the efficiency of medical teams in diagnosis and treatment decision-making, and facilitates the development of personalized treatment plans aimed at maximizing therapeutic success.
However, our study has several limitations: (1) As a retrospective analysis, the cases were sourced from a single medical center, which may limit the generalizability of the findings. (2) Not all patients underwent systematic imaging to exclude concurrent pulmonary involvement. Subclinical lung lesions could potentially induce systemic inflammatory responses, thereby influencing biomarker levels. Similarly, acid-fast bacillus blood cultures were not performed uniformly across all patients. (3) A number of patients were referred to our institution from lower-level hospitals, leading to delays in the diagnosis of bone and joint tuberculosis in some cases. (4) For the majority of patients, detailed preoperative anti-tuberculosis regimens were unavailable. As a result, the relationship between the duration of preoperative anti-tuberculosis therapy and different stages of bone and joint tuberculosis could not be reliably assessed in this study. (5) The study did not account for individual genetic variations that may influence susceptibility, disease progression, and severity of osteoarticular tuberculosis.
Therefore, future research should involve multi-center clinical trials and extend to diverse regions and populations to continuously validate and refine this staging system. In addition, integrating genetic data will be essential to further enhance the classification framework.
Acknowledgements
Thanks to the researchers who participated in this study for their work in this study. Thanks to the Fourth People’s Hospital of Qinghai Province for its technical support for this study. Thanks to the Qinghai Province Health Commission for funding this research.
Abbreviations
- Abbreviation
Full English name
- QFOT
Osteoarticular tuberculosis At Qinghai Fourth People’s Hospital
- TB
Tuberculosis
- PTB
pulmonary tuberculosis
- EPTB
extrapulmonary tuberculosis
- OATB
osteoarticular tuberculosis
- IGRT
interferon gamma release test
- ESR
erythrocyte sedimentation rate
- MMP
matrix metalloproteinase
- PCT
procalcitonin
Author contributions
XW: Conceptualization, methodology, data curation and writing. XS: Project management and supervision. BS and HY: Formal analysis and data curation. BS, HY and WC: Survey and data collection. XS: Writing-reviewing and editing. All authors finally approved the upcoming edition.
Funding
This work is supported by the following funds: Research project funded by the Qinghai Provincial Health Commission. Number: 2022-WJZDX-62, This financial support is provided to the author: XW, BS, HY, WC, XS.
Data availability
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation. For data acquisition, please contact Xie Wei.
Declaration
Ethics approval and consent to participate
Informed consent: The Ethics Committee of the Fourth People’s Hospital in Qinghai Province (2024 Ethics Review [71]) abandoned the informed consent requirement for this study because the study was a retrospective study and therefore anonymous data were used during the study. Privacy Protection: We strictly abide by relevant privacy protection laws and guidelines and take necessary measures to ensure the confidentiality and security of participants’personal information and data. Ethical Review and Approval: The study on human participants, human materials or human data in this study was conducted according to the Helsinki announcement and was approved by the Ethics Committee of the Fourth People’s Hospital of Qinghai Province.
Consent for publication
Since the manuscript does not contain information or images that may lead to the identity of the research participant, it is not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Xie Wei and Bai Shenglu contributed equally to this work.
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Associated Data
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Data Availability Statement
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation. For data acquisition, please contact Xie Wei.