Clinical Cases in Pharmacology Clinical Cases  ·  Rheumatology Vol. I: Inflammatory Arthritis  ·  Crystal-Induced Arthropathies
Rheumatology Vol. I: Inflammatory Arthritis, Case 0010 — Crystal-Induced Arthropathies

A Pseudogout Flare With Both Standard Options Closed by the Same Kidney

A single patient's pseudogout flare would ordinarily reach for one of two standard drugs. The disagreement is what to do once advanced kidney disease has quietly closed both doors at once.

Abbreviations, terms, and other agents mentioned in this case CPPD — calcium pyrophosphate deposition disease  ·  eGFR — estimated glomerular filtration rate  ·  IA — intra-articular  ·  A1c — hemoglobin A1c  ·  CKD — chronic kidney disease  ·  EULAR — European Alliance of Associations for Rheumatology
Presentation

Vivian S., an 82-year-old woman, moved into assisted living last year after a fall left her daughter uneasy about her living alone, a transition she resisted for months before agreeing to it and has since, by her own account, come to prefer — she runs the facility's small book club every Tuesday, a role she inherited almost by accident and has held onto with real pride, having spent thirty years as a librarian before retiring. She woke two days ago with her right knee swollen, warm, and too painful to bear weight, bad enough that she skipped book club for the first time anyone there can remember, an absence the staff noticed before she'd even mentioned the pain herself. Arthrocentesis showed rhomboid, weakly positively birefringent crystals consistent with CPPD, with a cell count and Gram stain that argue against superimposed infection.

Her chronic kidney disease, stage 4, attributed to decades of hypertension and a decade of poorly controlled type 2 diabetes, closes off the two drugs that would ordinarily be reached for first. NSAIDs carry real nephrotoxicity and fluid-retention risk at any stage of significant CKD, and are relatively contraindicated at hers. Colchicine is not absolutely prohibited in renal impairment, but her eGFR of 24 falls in the band the label calls severe, where it specifies a starting dose of 0.3mg daily rather than leaving the reduction to judgment as it does between 30 and 50; its narrow toxic margin makes accumulation at her filtration rate a genuine risk rather than a theoretical one — particularly in a patient whose actual weight and frailty put her at the more vulnerable end of the dosing range even before her kidneys are factored in. Her diabetes, meanwhile, is a real if softer consideration against systemic corticosteroids, which would push her already-elevated glucose higher still.

Vivian S. · 82 Monoarticular flare, right knee
History
Hypertension ×30 years, type 2 diabetes ×10 years, CKD stage 4, prior fall 1 year ago
Renal function
eGFR 24, stage 4 CKD
Glycemic control
A1c 8.1%, on metformin held for renal function and glipizide
Synovial fluid
Rhomboid, weakly positively birefringent crystals; no organisms, cell count consistent with crystal arthropathy
Exam
Right knee effusion, warm, unable to bear weight, monoarticular
Frailty
Low body weight (52kg), one fall in the past year

One joint, two closed doors, and a frail patient in between

Rheumatologist Opening

This is a single joint, and her synovial fluid analysis has reasonably excluded infection. That puts us exactly where the EULAR CPPD recommendations put intra-articular corticosteroid injection — first-line for acute CPP crystal arthritis in an accessible joint once sepsis is off the table. Real anti-inflammatory effect delivered locally, with essentially no systemic renal or glycemic exposure. It sidesteps both of the problems her kidney has created for us at once.

Geriatrician Response

I agree it's the right first move, but I'd want a wider margin than "one injection and see." She's 82, lives in assisted living after one fall already, and prolonged pain or reduced mobility while we wait to see if the injection fully works carries real risk of another fall or a longer functional setback than a younger patient would face from the same delay. A short, carefully-dosed oral corticosteroid course alongside the injection gives more certainty, even if it means watching her glucose more closely for a few days.

The injection's local effect is real, but "essentially no systemic exposure" isn't the same as "guaranteed complete response" — for a frail patient, I'd rather not find out which one this is the hard way.

Clinical Pharmacologist Final

Worth naming for the record: colchicine isn't fully closed off at her renal function, only more constrained — the label's own severe-impairment entry gives a concrete starting figure, 0.3mg daily, rather than an instruction to avoid, so it could serve as a genuine second option if the injection and short steroid course together don't fully resolve her symptoms. I wouldn't start it today, but I'd rather we have it named as a real fallback than treat this as a two-choice problem with nothing held in reserve.

Regimen selected
Intra-Articular Triamcinolone
Corticosteroid, Local · Single injection, right knee
First-line for monoarticular CPPD flare once infection has been reasonably excluded, per the EULAR CPPD recommendations; avoids systemic renal or glycemic exposure entirely.
Prednisone (short course)
Corticosteroid, Systemic · 20mg daily, tapered over 5 days
Added alongside the injection for a wider safety margin against incomplete response given her frailty, with glucose monitored more closely during the short course.
Colchicine — Held in Reserve
Reduced dose, contingent
Not started today; named explicitly as a real second option at the label's severe-impairment starting dose of 0.3mg daily, if injection and the short steroid course don't fully resolve her symptoms.
NSAIDs — Ruled Out
Considered, not adopted
Renal and fluid-retention risk at stage 4 CKD was judged to outweigh any benefit given effective, lower-risk alternatives are available.
Where this was left

Agreed: intra-articular injection with a short prednisone course, glucose monitored closely for the duration, and reduced-dose colchicine named explicitly as the next step if symptoms don't resolve within a few days rather than left unaddressed as an assumption.

Not fully settled: how much additional frailty-driven caution should shape future flares if this one recurs, since her CKD and glycemic status aren't likely to improve. The geriatrician wants a lower threshold for combining injection with systemic steroids going forward; the rheumatologist would reassess case by case rather than pre-commit to combination therapy for every future flare.

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