New Algorithm to Enhance Diagnosis and Treatment of Drug-Resistant Bone, Joint, and Spine Tuberculosis: Study
India: In a major development, the researchers have identified an algorithm for identifying presumptive drug resistance (PDR) in spinal and bone tuberculosis (TB) and outlined the necessary steps for confirming drug resistance in such cases. The newly developed diagnostic algorithm unveiled a systematic approach to identifying drug-resistant TB strains.
The algorithm, described in the Indian Journal of Orthopaedics details key steps to ensure accurate diagnosis and effective treatment.
"Based on the criteria described, we should suspect PDR (TRD) and proceed with procuring and submitting tissue samples for acid-fast bacilli (AFB) smear, histology, and both phenotypic and genotypic drug susceptibility testing (DST) to diagnose TB," the researchers wrote.
The study stated that genotypic and phenotypic DST is effective in identifying drug resistance in approximately 90% of cases. For the remaining less than 10% where DST results are inconclusive despite strong clinical suspicion of drug resistance, these cases may be treated as CDR or MDR. It's crucial to monitor adverse drug reactions and hepatic side effects closely and continue treatment until a healed status is confirmed.
The study's lead author Dr. Anil K. Jain from the University College of Medical Sciences, University of Delhi, explained to Medical Dialogues that, "the research introduces an algorithm for identifying presumptive drug resistance in spinal and bone TB and outlines the necessary steps for confirming drug resistance in such cases. It also provides evidence on diagnosing and treating confirmed drug-resistant cases, as well as addressing situations where drug resistance cannot be established despite thorough laboratory investigations. By proposing this algorithm, the study offers a scientifically grounded approach to managing these cases as a public health measure."
Drug-resistant TB in the bones, joints, and spine presents significant hurdles for healthcare providers, particularly as treatment resistance becomes more prevalent. The study highlighted the importance of a comprehensive diagnostic algorithm and rigorous monitoring for the effective management of drug-resistant bone, joint, and spine tuberculosis, offering new hope for patients.
Dr. Jain further elaborated on the motivation behind the study: "Drug-resistant osteoarticular TB is undermining our efforts to eliminate tuberculosis. Diagnosing and treating deep-seated paucibacillary TB in the spine and joints presents additional challenges. Identifying drug-resistant TB in these areas remains particularly difficult. There was a significant lack of literature to guide the suspicion, investigation, diagnosis, and treatment of drug-resistant spinal and bone TB."
In response to these challenges, Dr. Jain and his team conducted a series of studies to develop an algorithm for investigating and treating therapeutically refractory disease (TRD) or presumptive drug resistance (PDR) cases of osteoarticular TB (OATB). Starting from 2006, research was undertaken at the University College of Medical Sciences and GTB Hospital, New Delhi. The studies aimed to establish evidence on how to suspect, investigate, and effectively treat drug-resistant spine and bone TB. This research has led to the presentation of an algorithm designed to address these difficult cases, marking a significant advancement with one of the largest cohorts of drug-resistant spine and bone TB.
The series of six studies conducted by Dr. Jain and his team included:
- Study 1 and Study 2 focused on evaluating cases labeled as therapeutically refractory TB and suspected of being drug-resistant. These studies established criteria for identifying drug-resistant cases based on predefined indicators.
- Studies 3, 4, and 5 investigated 176 cases of paucibacillary spine and bone TB using a comprehensive set of laboratory tests. The research concluded that to diagnose TB in bone-affecting tissues, samples should be subjected to AFB smear, TB culture, histology, and molecular methods (CBNAAT and LPA) simultaneously. For limited tissue samples, histology and CBNAAT were particularly effective for confirming the diagnosis. The use of molecular methods alongside TB culture was beneficial for detecting drug resistance.
- Study 6, which reviewed the outcomes of cases with drug-resistant bone and spine TB, provides insights into treatment effectiveness.
Based on these findings, the proposed algorithm guides the suspicion, investigation, diagnosis, and treatment of drug-resistant spine and bone TB. Dr. Jain's work significantly advances the management of these challenging cases through a scientifically grounded approach.
"Since various studies were conducted at different times, hence laboratory facilities were variable. There is scope of conducting prospective study in a large series of all such cases," the researchers concluded.
Reference:
Jain, A.K., Jain, P., Jaggi, K. et al. Drug-Resistant Bone, Joint and Spine Tuberculosis: Evolution of Diagnosis and Treatment. JOIO 58, 661–668 (2024). https://doi.org/10.1007/s43465-024-01138-y
