Stopping antibiotic therapy and follow-up

In step 2.13 a decision was made to stop Linezolid at day 33 of a planned 42-day course of antibiotics (of which 26 days was Linezolid), because of adverse effects.

At this stage, the patient’s wound has healed well and there is no suggestion of recrudescence. The main dilemma, which is a common occurrence within a COPAT service, is what to do next.

There is no high-quality clinical evidence that strongly suggests completing the planned 42-day course of antibiotic therapy is mandated in this situation. On-the-other-hand, 6 weeks of antibiotics following surgery has become a global standard-of-care in managing chronic bone infections and it is therefore possible that one might be criticised if the planned course of therapy is not completed and recrudescence subsequently occurs. The options are therefore:

1. Stop antibiotic therapy altogether

2. Switch the patient to an alternative oral antibiotic such as Amoxicillin, Co-trimoxazole, Doxycycline or Tedizolid based on the available antimicrobial susceptibilities

There is probably no one, correct approach to this situation and what one does may vary from patient to patient depending on their views and other factors such as clinical progress to date, drug-drug interactions and comorbidities.

In this case, the patient and the OPAT team made a shared decision (as discussed in week 1; please find resources in see also below) to stop therapy on the basis that it was unlikely a further 9 days of antibiotics would alter the likelihood of recrudescence in the future. There were also concerns about adverse effects due to a new antibiotic; the benefits of continuing did not clearly outweigh the risks of stopping in this case.

The patient was booked in for a further review one week later to ensure the adverse effects were settling and his Hb was increasing (Hb 101 g/L at this review).

Importance of follow up

The latter is important as in our experience anaemia can continue to deteriorate in the weeks after stopping Linezolid in a small proportion of patients, usually those with other risk factors for bone marrow suppression, and in some cases may require a blood transfusion; 3% of patients treated with Linezolid overall based on data shown in the slide-show in step 2.7.

Therefore, we follow-up patients weekly until the anaemia/thrombocytopenia is clearly resolving (one week for most patients with linezolid-associated bone marrow suppression, but sometimes longer is required). We also ensure an iron profile and vitamin B12 and folic acid levels are performed, and replacement therapy started if necessary, to ensure no concomitant causes of anaemia.

Outpatient follow-up was organised for this patient in our sub-speciality bone and joint infection clinic. A subsequent CT scan showed changes in keeping with recent surgery and resolution of intra- and extra-cranial infection.

Share your final thoughts on this case with your fellow learners in the comments, particularly if you would have done anything different.