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Neurology II, Case 0011 — Movement Disorders

New Wilson’s Disease with Neurological Symptoms: Penicillamine’s Real Risk of Early Neurological Worsening

A new diagnosis, two chelators, and a real difference in early neurological risk between them for her specific presentation.

Abbreviations, terms, and other agents mentioned in this case KF rings — Kayser-Fleischer rings
Presentation

Maya O., 19, is home from her sophomore year of college after her roommate noticed her speech had started sounding slurred over several weeks, subtle enough at first that Maya herself attributed it to being tired during midterms, along with a slight tremor in her right hand that made her handwriting increasingly hard for her to read back. A slit-lamp exam ordered once her presenting symptoms raised concern found bilateral Kayser-Fleischer rings, and her workup — low serum ceruloplasmin, elevated 24-hour urinary copper, and genetic testing pending but not required to start treatment given how strongly her clinical picture already points one direction — confirmed Wilson's disease, an autosomal recessive disorder of copper metabolism that, left untreated, progresses from exactly the neurological picture she has now toward more severe dysarthria, dystonia, and psychiatric symptoms as copper continues to accumulate in her brain and liver. She has no prior liver symptoms, and her liver enzymes today are only mildly elevated, but her neurological presentation, not a hepatic one, is what brought her in — a distinction that matters directly to the decision in front of her team today.

Copper-chelating therapy is the mainstay of treatment, and penicillamine has the longest history of the two oral chelators available, in continuous use since the 1950s with a well-established record of long-term efficacy. But penicillamine carries a real, specifically neurological risk that trientine largely avoids: a meaningful proportion of Wilson's disease patients, particularly those presenting neurologically rather than hepatically, as Maya is, experience an initial worsening of their neurological symptoms when penicillamine therapy begins, thought to result from the drug's own rapid mobilization of copper from tissue stores into the bloodstream faster than the body can safely clear it — a paradoxical deterioration that can, in a genuine minority of cases, become permanent rather than resolving once chelation continues. Trientine chelates copper through a different binding mechanism and has historically been considered somewhat less potent for rapid initial decoppering, though the strongest recent randomized evidence for the newer formulations, the CHELATE trial (Schilsky et al., 2022), tested trientine tetrahydrochloride against penicillamine only as maintenance therapy in adults already stable on penicillamine for at least a year, and found it non-inferior in that setting. That is not the question Maya presents. Nothing in CHELATE speaks to initiating chelation in a previously untreated patient with neurological disease, and it was not designed to measure initial neurological worsening at all — so the case for choosing trientine here rests on the observed pattern of that worsening risk with penicillamine in neurologically presenting patients, not on a trial that enrolled a different population answering a different question.

Maya O. · 19 New Diagnosis
Diagnosis
Wilson's disease confirmed: low ceruloplasmin, elevated 24h urinary copper, bilateral KF rings
Presentation
Neurological: dysarthria, right-hand tremor; onset over several weeks
Liver enzymes
Mildly elevated; no hepatic decompensation, no prior liver symptoms
Genetic testing
Pending; not required to start treatment given clinical picture
Current medication
None started
Family
No known prior Wilson's diagnosis; sibling screening not yet initiated

New diagnosis, first treatment decision

Neurologist Opening

Maya's presentation is neurological, not hepatic — dysarthria and tremor are what brought her here. Penicillamine has a real, documented risk of paradoxical neurological worsening at initiation specifically in patients presenting this way, thought to come from the drug mobilizing tissue copper into the bloodstream faster than it can be safely cleared. I'd start trientine first-line for her given that risk concentration.

Hepatologist Response

I won't dispute that the neurological-worsening risk is real and specifically relevant to her presentation. Penicillamine still has decades of established efficacy behind it, though, and some clinicians consider its decoppering potency worth that risk when disease could otherwise progress untreated. A slow, low-dose initiation with close monitoring is a reasonable alternative to switching by default.

I'd want to be careful about treating trientine's 'more recent' comparable-efficacy data as fully settled without being specific about which formulations and follow-up periods that data actually covers.

Clinical Pharmacologist Final

Given her presentation is neurological, I'd go with trientine first-line here. And separate from which chelator wins this debate: pyridoxine supplementation needs to start alongside whichever drug we choose, since penicillamine independently reduces active vitamin B6 — a distinct mechanism from the neurological-worsening question, and not something that should get decided by which chelator we pick.

Regimen selected
Trientine
Copper Chelator · First-Line
Initiated because of her neurological presentation specifically — chosen on the observed initial-worsening risk that concentrates in neurologically presenting patients started on penicillamine, not on maintenance-phase equivalence data drawn from a different population.
Pyridoxine (Vitamin B6)
Supplementation · Started Alongside
Added regardless of chelator choice, given penicillamine's — and prudently, chelation therapy generally's — effect on B6 status.
Penicillamine
Considered, Not Started First
Documented as a reasonable alternative if trientine proves inadequate, not ruled out permanently.
Zinc (Maintenance-Phase)
Held in Reserve
Named as the eventual maintenance-phase option once initial decoppering with trientine is complete.
Low-Copper Diet Counseling
Adjunct, Started Today
Dietary counseling given alongside pharmacologic therapy.
Where this was left

Agreed: start trientine as first-line chelator specifically because of her neurological presentation, with pyridoxine supplementation started alongside regardless, and low-copper dietary counseling given today. Explicit documentation that penicillamine remains a real fallback option, not a permanently closed door, if trientine doesn't adequately control her disease. Siblings flagged for Wilson's disease screening given the autosomal recessive inheritance pattern, a separate family-level action item agreed without disagreement.

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