Objectives: To study the characteristics of bone or joint tuberculosis (TB) accompanied by TB in other organs (especially the lung), and to study patients' and doctors' delay in detecting bone or joint TB.
Subjects and methods: A retrospective study was conducted on 33 patients with bone or joint TB concurrent with TB of other organs, especially the lung, who were admitted to our hospital between 1981 and 2005. The patients were divided into the following three groups according to the organ of concurrent TB : (1) miliary TB group (N = 10), (2) pulmonary TB group (N = 19), and (3) other TB site group (N = 4). The relationship between bone/joint TB and TB of other organs was studied by comparing the three groups with respect to the time of appearance of musculo-skeletal symptoms or signs such as swelling and pain and that of symptoms or signs originating from other organs, such as cough, sputum, miliary pattern on chest radiograph and superficial lymph node swelling.
Results: The mean age (SD) of patients was 50.5 (18.9) yr, and the male to female ratio was 23 : 10. Among 33 patients, bone TB (including 18 spinal TB) was detected in 24 patients, joint TB in 14, and abscess in 3 (concurrent lesions in some patients). The mean intervals from onset of symptoms to consultation (patients' delay), from consultation to diagnosis (doctors' delay) and from symptom onset to diagnosis (total delay) were 5.5 (13.9), 3.4 (5.2) and 8.9 (13.9) months, respectively. (1) Bone/joint TB concurrent with miliary TB (N = 10) In 8 patients with mean age of 61.0 (17.4) yr, musculo-skeletal symptoms/signs preceded respiratory symptoms or appearance of miliary pattern on chest radiograph by 7.8 (7.2) (range; 1-24) months. The patients', doctors' and total delays were 0.4 (0.5), 7.3 (7.8), and 7.7 (7.6) months, respectively. In most cases, bone/joint TB was diagnosed after the onset of miliary pattern on chest radiograph. In one patient with simultaneous onset of musculo-skeletal and respiratory symptoms/signs (age 21 yr), the interval of total delay was 1 month, and in one patient with musculoskeletal symptoms which appeared six months later than respiratory symptoms (age 28 yr), the interval of total delay was 2 months. (2) Bone/joint TB concurrent with active pulmonary TB (N = 19). In this group, the mean age was 52.2 (17.1) yr, and males were predominant (M/F = 15/4). Active pulmonary TB was diagnosed by positive sputum culture in 13 patients, by positive sputum smear or PCR results in 4 patients, and by the clinical course in 2 patients. Ten patients (53%) had a previous TB history. Cavitary lesion was observed in 15 patients, and the upper lobes were predominantly involved on chest radiograph in 19 patients, indicating that the pulmonary TB was probably post-primary (reactivation) in all patients. In 9 patients with mean age of 49.7 (15.7) yr, musculo-skeletal symptoms/signs preceded respiratory symptoms by 14.1 (14.0) (range; 4-48) months. The patients', doctors' and total delays were 13.3 (17.8), 3.8 (6.6), and 17.1 (16.1) months, respectively. On the other hand, in 10 patients with mean age of 54.5 (18.7) yr, musculo-skeletal symptoms/signs and respiratory symptoms/signs appeared simultaneously, and the total delay was 2.7 (1.9) months. Twelve of 19 patients (63%) had complications such as diabetes mellitus, steroid use, and liver diseases. In cases with miliary or pulmonary tuberculosis, the total delay in diagnosis (Y) correlates positively with the time lag from onset of musculo-skeletal symptoms to respiratory symptoms/signs (X), and the regression line (Y = 0.94X + 2.3, r = 0.98, p < 0.001) was almost linear (Y = X), indicating that the diagnosis of bone/joint TB was made just after the diagnosis of miliary or pulmonary TB. (3) Bone/joint TB concurrent with TB of other sites (N = 4) In 2 female cases (21 and 28 yrs) with cervical lymph node TB, musculo-skeletal symptoms/signs and cervical lymph node swelling appeared simultaneously. In a 54-yr male patient, musculo-skeletal symptoms/signs appeared 5 years after appearance of testicular enlargement, and testicular TB was diagnosed by biopsy simultaneously. In a 33 year-old male patient, musculo-skeletal symptoms/signs appeared 7 months after the drainage of pleural and pericardial effusions (TB was not diagnosed initially), and then the diagnosis of bone/joint, pleural, and pericardial tuberculosis was made for the first time.
Conclusions: In middle-aged or elderly patients with active bone/joint TB, miliary TB is sometimes caused by bacillemia originating from the infected bone/joint lesions. In cases with bone/joint TB and concurrent pulmonary TB, bone/joint TB and pulmonary TB are probably reactivated independently as a result of decreased systemic immunocompetence.