02 July 2026
: Case report 
Tacrolimus-Induced Thrombotic Microangiopathy in a Kidney Transplant Recipient After Treatment for Acute Allograft Rejection
Unusual clinical course, Challenging differential diagnosis, Unusual or unexpected effect of treatment, Diagnostic / therapeutic accidents, Adverse events of drug therapy, Clinical situation which can not be reproduced for ethical reasons
Yen-Hao Liao ABDEF 1*, Ming-Yi Huang DF 1DOI: 10.12659/AJCR.953247
Am J Case Rep 2026; 27:e953247
Table 2 Application of the Naranjo Adverse Drug Reaction Probability Scale to the present case. The total score was 9, consistent with a definite causal relationship between tacrolimus exposure and thrombotic microangiopathy.
| Naranjo Adverse Drug Reaction Probability Scale | Total score: 9 |
|---|---|
| 1. Are there previous conclusive reports on this reaction? | +1 (yes) |
| 2. Did the adverse event appear after the suspected drug was administered? | +2 (yes) |
| 3. _Did the adverse reaction improve when the drug was discontinued or a specific antagonist was administered? | +1 (yes) |
| 4. Did the adverse reaction reappear when the drug was readministered? | +1 (yes) |
| 5. _Are there alternative causes (other than the drug) that could independently have caused the reaction? | +2 (no) |
| 6. Did the reaction reappear when a placebo was given? | 0 (do not know) |
| 7. Was the drug detected in the blood (or other fluids) at concentrations known to be toxic? | 0 (no) |
| 8. _Was the reaction more severe when the dose was increased or less severe when the dose was decreased? | +1 (yes) |
| 9. Did the patient have a similar reaction to the same or similar drugs during any previous exposure? | 0 (do not know) |
| 10. Was the adverse event confirmed by any objective evidence? | +1 (yes) |