Crystal / Obstructive Nephropathy
Intratubular precipitation of drug or metabolite — high-dose methotrexate and tumor lysis crystals.
Agents’ overall severity
Each agent’s whole-drug severity grade, not the severity of this lesion specifically — an agent whose signature injury is elsewhere can still be graded severe here.
Agents’ overall reversibility
Agents’ onset window
How soon each agent’s kidney toxicity typically appears — a whole-drug tempo, not specific to this lesion.
Real-world reporting for this lesion
FAERS across all lesions →Agents with a disproportionate FAERS reporting signal for crystal / obstructive nephropathy (reporting odds ratio with a 95% CI lower bound above 1) — a spontaneous-reporting signal, not incidence or proven causation. FAERS carries reporting and indication biases and has no denominator.
Documented in the atlas profile and carrying a FAERS signal — the strongest claim the atlas makes.
Documented in a profile with no reporting signal. Mostly expected: naming this lesion on a report can require a biopsy, and silence is not evidence against the literature.
A real reporting signal that is not evidence for this drug-lesion pair: no MedDRA term names it, the naming subset asked alone came back flat, or the 2026-08 review attributed the reporting to the population, co-therapy, or class-level literature.
The terms that name this lesion are disproportionate, but no profile documents it for that agent. Most are echoed by a sibling agent in the same class. Leads for review, never lesions the atlas claims.
49 agents with a significant XTAL reporting signal.
Management approach
Full framework →Prevent precipitation; for established high-dose methotrexate toxicity, glucarpidase rapidly cleaves circulating drug.
Drug-level levers
- Hold further methotrexate until clearance and renal recovery.
- For tumor-lysis urate nephropathy, prophylaxis is the key lever.
Pharmacologic toolkit
- Hydration + urinary alkalinization — Vigorous IV hydration and urine alkalinization keep methotrexate soluble.
- Leucovorin rescue — High-dose leucovorin guided by serial methotrexate levels.
- Glucarpidase — For delayed methotrexate clearance / AKI: recombinant carboxypeptidase-G2 cleaves plasma methotrexate, usually allowing recovery without dialysis.
- Rasburicase (tumor lysis) — For urate crystal nephropathy from tumor lysis, with hydration; also manage hyperphosphatemia.
When to biopsy
Not indicated — the diagnosis is clinical and biochemical (drug levels, uric acid, urine crystals).
Monitoring
- · Serial methotrexate levels, creatinine, urine pH
- · Uric acid, phosphate, potassium (tumor lysis)
Educational use only. Educational synthesis of the published literature — not a treatment protocol, dosing guide, or medical advice. Regimens and agents shown are illustrative of what the literature describes; verify against current guidelines (ASON / KDIGO / ASCO / NCCN) and individualize to the patient. Using this site creates no clinician–patient relationship.
What the guidelines say
All guidelines →Society and consensus recommendations that speak to crystal / obstructive nephropathy.
Each recommendation below is this atlas's faithful summary of the source, not a quotation from it — follow the PubMed link for the wording the society published. Summaries may be superseded; consult the current full text and individualize to the patient.
Cited incidence across agents
Where the literature gives a representative crystal / obstructive nephropathy figure, the agents ranked highest first. Hover a dot for its cited note.
Offending agents
Signature offenders
18Agents for which crystal / obstructive nephropathy is the defining renal lesion.
Also associated
28Agents that cause crystal / obstructive nephropathy as a secondary pattern alongside a different signature lesion.