Clinical, radiological and molecular diagnosis correlation in serum samples from patients with osteoarticular tuberculosis.

OBJECTIVE

To assess the role of polymerase chain reaction (PCR) in serum samples, in the diagnosis of osteoarticular tuberculosis (OTB) in a setting where only clinical and imaging diagnoses determine the treatment.

METHODS

A total of 44 consecutive serum specimens were collected from clinically suspected OTB patients, based on clinical and radiological [X-ray or magnetic resonance imaging/computed tomography] features. They were screened by in-house nested PCR. In addition, a few specimens were examined by Gram stain, acid-fast bacilli stain, histopathology and routine bacterial culture. A total of 39 specimens were collected from patients suffering from other bone diseases of nontuberculous origin and included as negative controls.

RESULTS

Of the 44 clinically suspected OTB patients, in-house nested PCR was positive in 40 (91%) cases; PCR was negative in 38 (97%) negative controls. Sensitivity and specificity of our in-house nested PCR was 90.9% and 97.4%, respectively. The PCR report was available within 48 h. It was possible to standardize serum PCR technique and in positive cases, a good correlation was observed in terms of an adequate treatment response.

CONCLUSIONS

Nested PCR in serum samples is a rapid, highly sensitive and specific modality for OTB detection. PCR should be performed in addition to clinical evaluation, imaging studies, acid-fast bacilli staining, culture and histopathology diagnosis, if possible.