Interference of Residual 99m Tc-MIBI Activity in Syringe Needle on 99m Tc-DMSA Scan Interpretation; Medical Error

Area of Science:

• Pediatric Nephrology
• Nuclear Medicine Imaging
• Diagnostic Accuracy

Background:

• A 4-month-old infant presented with a small right kidney, necessitating a technetium-99m dimercaptosuccinic acid (99mTc-DMSA) scan.
• Initial scan results were anomalous, suggesting severe bilateral renal pathology.

Purpose of the Study:

• To investigate the cause of unjustifiable findings on a 99mTc-DMSA scan in an infant.
• To emphasize the importance of procedural integrity in nuclear medicine.

Main Methods:

• Retrospective analysis of a 99mTc-DMSA scan performed on a 4-month-old infant.
• Identification of needle reuse and contamination with technetium-99m methoxyisobutyl isonitrile (99mTc-MIBI) as the source of error.
• Performance of a repeat 99mTc-DMSA scan after correction.

Main Results:

• The initial scan falsely indicated global cortical loss in the left kidney and increased uptake in the liver and bowel.
• Contamination from a reused needle with residual 99mTc-MIBI compromised scan quality and falsely elevated right kidney function.
• The repeat scan revealed normal left kidney uptake and significantly reduced right kidney function, indicating the initial findings were erroneous.

Conclusions:

• Reuse of sterile needles contaminated with radioisotopes can compromise nuclear medicine scan quality and lead to diagnostic errors.
• Adherence to safe techniques, use of disposable equipment, workflow review, and transparent error reporting are essential in nuclear medicine.
• Ensuring procedural accuracy is critical for reliable diagnosis and patient safety in pediatric imaging.