| SOI | severity of illness |
|---|---|
| SSLI | serum sickness-like illness |
| TIS | tetracycline-induced steatosis; transdermal infusion system; triage illness scale; trypsin-insoluble... |
| UCI | unusual childhood illness; urethral catheter in; urinary catheter in |
| URI | uniform resource identifier; upper respiratory illness; upper respiratory infection |