Low tacrolimus, rising creatinine, and a patient who cannot afford her medicine
Ms. L, 42, is five months from a deceased-donor kidney transplant (donor CMV positive, recipient CMV negative). She takes tacrolimus, mycophenolate, and prednisone. Her baseline creatinine is 1.3 mg/dL. Today it is 1.9 mg/dL, tacrolimus trough is 4.2 ng/mL (target 6–8), WBC 3.1, temperature 37.9 °C, and she reports two weeks of fatigue and low back pain. She admits she has missed most of her evening tacrolimus doses because of a new shift schedule, and has been taking a friend's ibuprofen for her back. She mentions she skipped a refill because the copay was $180.
1. What is your priority differential, and what will you do today? Be specific about what you will and will not change yourself.
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Differential to hold simultaneously: acute cellular or antibody-mediated rejection (subtherapeutic tacrolimus is the leading driver here), drug-related nephrotoxicity, BK polyomavirus nephropathy, CMV or other infection, and obstruction/volume depletion as reversible contributors. The low-grade fever and leukopenia broaden the infection concern; the NSAID adds a hemodynamic/tubular insult.
Today:
- Notify the transplant team the same day - this is a time-sensitive combination of falling immunosuppression and rising creatinine, not a routine message.
- Obtain the labs the team will need: repeat BMP and tacrolimus level, urinalysis with microscopy, BK viral load, CMV viral load, CBC, and a urine protein measurement; arrange a bladder scan if obstruction is possible.
- Stop the ibuprofen and provide a safe analgesic. That is squarely within nursing scope and reversible.
- Escalate the copay problem today to the transplant pharmacist and social worker - manufacturer assistance, a generic formulation, a different dispensing schedule, or insurance appeal. Cost is the root cause here and no amount of reminding will fix it.
What I will not do: I will not adjust the tacrolimus dose myself, will not tell her to "double up" on missed doses, and will not schedule a biopsy or decide on rejection treatment - those are the team's calls. I will not delay reporting to arrange education first.
2. Write the education you would provide at this visit, with the rationale you would give for each point, and how you would check it was understood.
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Teach the "why" so the behavior makes sense:
- Adherence: tacrolimus has a narrow therapeutic window; a trough of 4.2 with a rising creatinine means her immune system has had room to act. Offer concrete fixes tied to her shift: a phone alarm, a pillbox carried in her bag, pairing the evening dose with a fixed event (end of shift), and a backup dose kept at work. Never "catch up" a missed dose without asking.
- NSAIDs: ibuprofen and naproxen reduce kidney blood flow, especially with tacrolimus; acetaminophen is her default analgesic. Check combination cold and sleep products.
- Fever and infection: a temperature of 37.9 °C with leukopenia on immunosuppression warrants a call, not a wait-and-see. Given D+/R− CMV status, she needs to know that fatigue and low-grade fever are the pattern to report and that food safety and hand hygiene matter.
- Reporting rules: any creatinine rise, decreased urine output, weight gain, fever, or new pain - call the transplant team before self-treating or buying OTC drugs.
- Cost: reassure her that financial barriers are a clinical problem the team manages, and that missing doses is never the solution.
Check understanding: use teach-back - she should name her evening dose, state what she does if she misses it, name one OTC drug she must avoid, and tell you the temperature at which she calls. Document the specific gaps you find and re-teach those, not the whole script.
3. The team wants to know whether this can be managed as an outpatient. What information and reasoning would you contribute?
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Frame it as risk stratification, not a yes/no opinion.
The features pushing toward closer or inpatient evaluation: a creatinine rise of roughly 45% from baseline in a patient with documented under-immunosuppression, leukopenia, and fever - the combination raises the possibility of rejection plus infection, and both are more cheaply treated early. The features supporting outpatient management if the team chooses it: she is hemodynamically stable, making urine, afebrile to a modest degree, and the modifiable causes (missed doses, NSAID, cost) are identifiable and addressable.
What I would supply: the trend data (baseline and current creatinine, tacrolimus levels over time), the vitals, the medication history including the ibuprofen and the missed doses, the cost barrier and what has been arranged, and whether she has reliable transportation and phone access - a 42-year-old living alone with a shift job may not be able to return in 48 hours.
If outpatient: a specific return date for labs within 48–72 hours, a named contact, written parameters for coming to the emergency department (fever above the team's threshold, decreasing urine output, weight gain, vomiting that prevents oral tacrolimus), and confirmation by teach-back that she can meet them. My job is to make the team's decision safe, not to make it for them.