Inflammatory mass of an intrathecal catheter in patients receiving baclofen as a sole agent: a report of two cases and a review of the identification and treatment of the complication.

INTRODUCTION: Intrathecal inflammatory masses or granuloma have been described extensively in the literature in patients receiving chronic spinal infusions for pain. After an extensive literature review, no reported cases of baclofen causing this disorder when administered as a sole agent were identified. Intrathecal baclofen has been used to treat spasticity secondary to stroke, multiple sclerosis, cerebral palsy, spinal cord injury, and other neurological disease. CASES: Two patients who received intrathecal infusions of baclofen to treat spasticity developed catheter failure. Magnetic resonance imaging analysis showed the presence of an inflammatory mass at the tip of each catheter causing the dysfunction. The catheters were removed and replaced by a percutaneous technique. DISCUSSION: Inflammatory mass on an intrathecal catheter can result in a variety of symptoms. These problems range from the patient being asymptomatic to flaccid paraplegia. Animal studies have shown an association with high concentrations of morphine and hydromorphone theorized to be related to a mast cell degranulation response. Presence of this lesion in these two patients should heighten the suspicion for inflammatory mass in any patient treated for spasticity. The diagnosis of intrathecal catheter tip inflammatory mass is made after an initial suspicion of a catheter occlusion or failure. The gold standard of diagnosis is T2-weighted magnetic resonance imaging. A computerized tomography myelogram is acceptable if a magnetic resonance imaging is not feasible.
CONCLUSION: We report two cases of inflammatory mass in patients receiving baclofen as a sole intrathecal agent. The authors would recommend vigilance in any patient receiving intrathecal baclofen. If the suspicion arises of this problem, a magnetic resonance imaging or computerized tomography myelogram should be obtained with a focus on the catheter tip.