Restarting TB Treatment in Patients Lost to Follow-up
TB treatment should be restarted based on the duration of interruption, with patients who interrupted treatment for 2 months or more requiring a complete restart of the full treatment regimen. 1
Assessment of Treatment Interruption
- Patients who interrupt TB treatment for less than 2 months generally can continue their original regimen to completion, with the earlier the break in therapy and the longer its duration determining the need to restart 1
- Patients who interrupt treatment for 2 months or more and return with active TB (smear/culture positive or clinically active disease) should be classified as "treatment after interruption" cases and require a complete restart of treatment 1
- Continuous treatment is more important in the initial phase of therapy when the bacillary burden is highest and the chance of developing drug resistance is greatest 1
Restarting Treatment Protocol
For patients who were previously on treatment for drug-susceptible TB and were lost to follow-up:
- Collect three sputum specimens for AFB smear microscopy, mycobacterial culture, and drug susceptibility testing before restarting treatment 2
- Perform chest radiography to assess disease extent and identify potential complications 2
- Conduct HIV testing if status is unknown 2
- Obtain baseline laboratory tests including liver function tests, especially for high-risk patients 2
For patients with presumed drug-susceptible TB:
Special Considerations
Risk of Drug Resistance
- NEVER ADD A SINGLE DRUG TO A FAILING REGIMEN as this risks development of resistance to the new drug 1
- For patients who did not receive directly observed therapy (DOT) or are known to have had irregular treatment in the past, assume a higher risk of acquired drug resistance 1
- If drug resistance is suspected, begin an expanded regimen with at least 3 drugs to which the organism is likely susceptible while awaiting susceptibility results 1
Monitoring After Restart
- Perform monthly clinical monitoring, including assessment for symptoms of hepatitis 2
- Obtain sputum cultures monthly until cultures become negative 2
- Repeat drug-susceptibility tests if sputum specimens remain culture-positive after 3 months or if cultures revert to positive after initial conversion 2
Factors Associated with Loss to Follow-up
Understanding these factors can help prevent future treatment interruptions:
- Male gender and younger age (15-25 years) are associated with higher risk of loss to follow-up 3
- Birth outside the country of treatment, history of homelessness, and unstable housing contribute to loss to follow-up 4
- Alcohol abuse is independently associated with loss to follow-up 5
- Severity of adverse drug reactions, particularly vomiting, increases risk of loss to follow-up 5
Strategies to Prevent Future Loss to Follow-up
- Provide assistance from the TB program (any type of support) 5
- Ensure patients have better TB knowledge through education 5
- Foster higher levels of trust in and support from physicians and nurses 5
- Consider using incentives during the treatment phase, though these should be carefully implemented 4
- Obtain alternative contact information to improve ability to locate patients 6
Common Pitfalls to Avoid
- Failing to collect appropriate specimens for culture and drug susceptibility testing before restarting treatment 2
- Adding a single drug to a failing regimen, which can lead to resistance to the added drug 1
- Not reporting the case promptly to the local public health department 2
- Underestimating the importance of directly observed therapy (DOT) for patients with a history of treatment interruption 1