Clinical Cases in Pharmacology Clinical Cases  ·  Infectious Disease I  ·  Bacterial Disease  ·  Post-Treatment Lyme Disease Syndrome
Infectious Disease I, Case 0017 — Bacterial Disease

Post-Treatment Lyme Symptoms and the Antibiotics That Won’t Fix Them

Her Lyme disease was treated correctly eight months ago. Her symptoms are real and unresolved anyway — and more antibiotics, the trials say plainly, won’t fix what’s actually still wrong.

Abbreviations, terms, and other agents mentioned in this case PLEASE — the 2016 Dutch randomized trial of prolonged antibiotic therapy for persistent symptoms attributed to Lyme disease  ·  PTLDS — post-treatment Lyme disease syndrome  ·  IDSA/AAN/ACR — the joint 2020 clinical practice guideline on Lyme disease from infectious disease, neurology, and rheumatology societies
Presentation

Katherine V., a 41-year-old high school English teacher, was diagnosed with Lyme disease eight months ago after a classic erythema migrans rash following a hiking trip, treated appropriately at the time with a full course of doxycycline that resolved her rash and initial symptoms. Since then she has developed persistent fatigue, joint aches migrating between her knees and wrists, and difficulty concentrating badly enough that she has taken a reduced teaching schedule this semester — real, functionally limiting symptoms that began within weeks of finishing treatment and have not meaningfully improved since. She has read extensively online about long-term antibiotic protocols for what some sources call "chronic Lyme disease" and has come to this visit specifically requesting several more months of oral or IV antibiotics, having heard from an online support group that this is what finally helped others.

Her current Lyme antibody testing remains positive, as expected after any adequately treated infection and not evidence of ongoing active disease, and she has no objective findings on exam — no synovitis, no focal neurologic deficit, no fever — consistent with post-treatment Lyme disease syndrome rather than persistent or inadequately treated infection. Klempner et al. in 2001 and Berende et al.’s PLEASE trial in 2016 both tested exactly her situation — prolonged antibiotics for persistent symptoms after standard Lyme treatment — and both found no sustained benefit over placebo, while Klempner documented real harms from extended IV exposure specifically. She is frustrated, tired, and increasingly convinced her doctors don’t believe her symptoms are real — a concern the team takes as seriously as the antibiotic question itself.

The persistent antibody positivity that sometimes drives patients and clinicians alike back toward more antibiotics is itself a documented source of the confusion here: IgG antibodies to Borrelia burgdorferi can remain detectable for years after a fully eradicated infection, a serologic scar rather than a marker of ongoing bacterial activity, since the assay measures immune memory, not live organism. Reading her positive titer as evidence the infection is still present, rather than as an expected finding in anyone successfully treated, is the exact misreading the trials on prolonged antibiotic therapy were designed to test — and the exact misreading her own online research, however well-intentioned, appears to have encouraged.

Katherine V. · 41 8 Months Post-Treatment
History
Erythema migrans 8mo ago, adequately treated with doxycycline
Current symptoms
Fatigue, migratory joint pain, concentration difficulty ×6mo
Exam
No synovitis, no focal neurologic deficit, afebrile
Serology
Persistently positive — expected after treated infection, not active disease
Trial evidence
Multiple RCTs: no sustained benefit from prolonged antibiotics for PTLDS
Patient request
Explicitly requesting extended antibiotic course

Infectious disease follow-up clinic

Infectious Disease Physician Opening

I can’t recommend further antibiotics, and I want to be direct about why — Klempner and the PLEASE trial both tested exactly this situation, prolonged antibiotics for persistent post-treatment symptoms, and neither found sustained benefit over placebo. Meanwhile the trials documented real harm from extended IV courses specifically — line infections, C. difficile. This isn’t a close call in the data the way some of our other cases have been.

Primary Care Physician Response

I agree with the evidence completely — I want to make sure how we say this doesn’t cost us her trust. She’s not making these symptoms up, and she came here specifically because she’s been made to feel dismissed before. If a flat "no, the trials don’t support it" is the whole conversation, I worry she leaves and finds a less careful source of exactly the treatment we’re declining.

Neurologist Final

I don’t think those two things are actually in conflict. We can tell her plainly what the trial data show — that’s not optional — while also being explicit that her symptoms are real and that "no proven benefit from more antibiotics" is not the same statement as "nothing is actually wrong." I’d walk out of this visit with her holding a concrete plan for her fatigue and joint pain, not just a declined request.

Regimen selected
Extended Antibiotic Course — Not Prescribed
Doxycycline or IV alternatives, declined
No demonstrated benefit over placebo in randomized trials for this exact presentation, with documented harm from prolonged IV exposure specifically.
Symptom-Directed Management Plan (non-antibiotic)
Referral-based, individualized
Offered as the concrete alternative — rheumatology evaluation for the joint symptoms, sleep and fatigue-focused primary care follow-up — rather than leaving the visit with only a decline.
Where this was left

Agreed: no further antibiotics prescribed, with the trial data explained directly and in full; referrals placed to rheumatology for her joint symptoms and to primary care for a structured fatigue work-up, with a follow-up visit scheduled in four weeks rather than leaving her plan open-ended.

Left genuinely unresolved from her side: she left the visit still hoping antibiotics might eventually be reconsidered, and was told honestly that new evidence could change that recommendation but none currently exists — the team chose not to promise reconsideration merely to soften the visit’s ending.

Educational content only — a composite teaching case, not a real patient encounter or a substitute for clinical guidance. About These Cases →