Disclosures: Kyle T Seko, DO: Nothing to disclose

Case Description: JM is a 53-year-old man with spastic paraplegia due to T7 traumatic spinal cord injury treated with intrathecal baclofen pump who presented to ED with 4 days of increased spasticity, generalized body aches, fever and pruritis. Exam was notable for a significantly increased lower extremity tone, as well as focal, fluctuant, swelling over the pump site.

Setting: Inpatient Tertiary Care Center

Patient: n/a

Assessment/Results: Initial workup was negative other than leukocytosis of 11.9. Pump interrogation revealed no motor stalls or alarms. To non-invasively test function of the pump given concern for pump site infection, a 50 mcg bolus was programmed, with equivocal clinical effect. In order to definitively evaluate points of possible failure, indium tracer study was conducted. Radiolabeled indium-111 diethylene-triamine-pentaacetic acid (111In-DTPA) was injected into the pump. Serial scintigrams obtained by nuclear medicine evaluated subsequent tracer distribution over the next 48 hours. At 48 hours the indium localized to the area directly around the pump, without activity in the tubing, CNS, or peritoneum, suggestive of pump or proximal catheter malfunction/obstruction. Patient was subsequently taken for pump replacement where a large defect in the distal catheter and a disconnected proximal catheter were discovered.

Discussion: In situations where there is concern for reservoir, as opposed to catheter, malfunction, radiologic contrast dye studies are non-diagnostic. Nuclear medicine scintigraphic imaging allows for use of a drug reservoir and pumping of the radiotracer at typical therapeutic speeds, allowing diagnosis of mechanical pump failure, catheter occlusion, catheter leak, restriction of free distribution in the CSF, or evaluation of refill port patency.

Conclusion: When investigating suspected baclofen pump malfunction, scintigraphic imaging possesses unique advantages that make it a valuable functional adjunct to other diagnostic studies.

Level of Evidence: Level V

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PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/its-never-the-pump-except-when-it-is-a-case-report-of-baclofen-pump-failure/