Rare spinal fungal granuloma removed successfully in a dog

A rare canine neurology case published July 21, 2026, in Frontiers in Veterinary Science suggests that aggressive surgery plus prolonged antifungal treatment can produce a meaningful recovery in a dog with a spinal intramedullary fungal granuloma, a lesion type the authors describe as exceptionally uncommon in veterinary medicine. In this case, a 7-year-old Miniature Schnauzer progressed from pelvic limb weakness to paraplegia before clinicians identified and excised a T12-T13 intramedullary mass, then transitioned the dog to long-term fluconazole therapy. (frontiersin.org)

The report matters partly because spinal fungal granulomas in dogs are so rarely documented. In their discussion, the authors say this is, to their knowledge, the first reported successful surgical resection of a spinal intramedullary fungal granuloma in a dog with a favorable long-term outcome. They contrast that with the broader veterinary literature, where fungal CNS infections are uncommon, often difficult to diagnose, and generally associated with a poor prognosis. Older reports have described successful management of other CNS fungal granulomas in dogs, including intracranial disease, but evidence specific to intramedullary spinal lesions has been sparse. (frontiersin.org)

Clinically, the dog initially fit a more familiar myelopathy workup. MRI showed an ill-defined, T2-hyperintense, strongly contrast-enhancing intramedullary lesion extending from the caudal endplate of T12 to the midbody of T13, with severe edema and meningeal enhancement. CSF analysis found severe mononuclear pleocytosis and markedly increased protein. Serology for Neospora caninum and Toxoplasma gondii was negative, and the dog was discharged on prednisolone and clindamycin while clinicians weighed inflammatory and infectious differentials. When neurologic status worsened within a week, exploratory surgery and excisional biopsy were pursued instead of euthanasia. (frontiersin.org)

Surgery proved decisive. Via right-sided T12-T13 hemilaminectomy, durotomy, and myelotomy, the team removed a well-defined, firm intramedullary mass. Histopathology identified an inflammatory pyogranuloma containing septate fungal hyphae, confirming fungal disease. Panfungal PCR on the formalin-fixed sample was negative, which the authors say may reflect delayed processing and the lower sensitivity of PCR on fixed tissue versus fresh samples. That point is especially useful in practice: a negative molecular result shouldn't outweigh histopathology when fungal elements are clearly seen. (frontiersin.org)

Postoperatively, the dog received fluconazole at 4.5 mg/kg twice daily. The authors note fluconazole is often favored for CNS fungal disease because it crosses the blood-brain and blood-spinal cord barriers more effectively than many alternatives. At two months, the dog had regained independent ambulation. At six months, follow-up MRI showed complete resolution of the lesion, and repeat CSF showed only mild residual abnormalities. Because of concern for persistent or subclinical infection, fluconazole was continued for another 12 months. Over that period, the dog remained ambulatory with mild paraparesis and reportedly had an excellent quality of life, later dying for unrelated reasons during anesthesia for routine lipoma removal 18 months after diagnosis. (frontiersin.org)

There doesn't appear to be substantial published outside commentary on this specific case yet, which isn't surprising given how recently it was published on July 21, 2026. Still, the paper's discussion aligns with prior veterinary and comparative literature suggesting that fungal CNS lesions can mimic neoplasia or sterile inflammatory disease, and that debulking may improve outcome by relieving mass effect and reducing organism burden. The authors also point out that organism-specific serology can have limited sensitivity in focal disease, especially for Aspergillus, making preoperative confirmation difficult and cost-benefit decisions around testing challenging for clinicians and pet parents. (frontiersin.org)

Why it matters: For veterinary professionals, this case sharpens the differential diagnosis for focal thoracolumbar intramedullary lesions and underscores the risk of anchoring too quickly on immune-mediated myelitis or neoplasia. In a deteriorating patient, tissue diagnosis may be the turning point, particularly when MRI and CSF are suggestive but nonspecific. The report also reinforces a practical pathology lesson: if fungal disease is even a remote possibility, collecting fresh tissue for culture or molecular testing may improve diagnostic yield compared with relying on formalin-fixed samples alone. (frontiersin.org)

What to watch: The next question is whether more centers report similar cases, allowing the field to move beyond anecdote on case selection, surgical timing, antifungal choice, and treatment duration. For now, this report offers cautious support for combined surgery and prolonged fluconazole in selected dogs with focal intramedullary fungal granulomas, but broader guidance will depend on additional case accumulation rather than controlled data. (frontiersin.org)