Brain Pathology Case of the Month - May 2014


Tophaceous pseudogout.


Tophaceous pseudogout is characterized by deposition of calcium pyrophosphate dihydrate (CPPD) crystals within soft tissue. The condition, which was first described in 1962, appears radiographically as chondrocalcinosis involving hyaline and fibrocartilage (5). Tophaceous pseudogout is most commonly sporadic and shows an association with a variety of conditions, such as prior surgery, trauma, gout, hyperparathyroidism, hypophosphatasia, hypomagnesemia, hemochromatosis, and Wilson' disease (3). The appendicular skeleton is most commonly affected, and involvement of the spine is relatively rare in comparison. The proposed mechanism of disease in the spine consists of nodular deposition of CPPD crystals in the ligamentum flavum or atlanto-occipital ligament, with ensuing myelopathy or cervicomedullary compression (1, 2, 7). The cervical spine is most commonly affected and the thoracic spine is least affected (5, 6). Because the presenting symptoms mimic more common conditions such as spinal stenosis, lumbar radiculopathy, spondylolisthesis, or cauda equina syndrome, tophaceous pseudogout is not usually considered at presentation (4, 6). The diagnosis is made by examining the tissue under polarizable light and demonstrating positive birefringence.

In the case of our patient, risk factors included age and remote history of laminectomy for spinal stenosis. The diagnosis was not considered at presentation and was established after histologic examination of the tissue under polarizable light. This case demonstrates involvement of the lumbar spine by tophaceous pseudogout.


  1. Berghausen EJ, Balogh K, Landis WJ, Lee DD, Wright AM (1987) Cervical myelopathy attributable to pseudogout. Case report with radiologic, histologic, and crystallographic observations. Clin Orthop Relat Res. (214):217-21.
  2. Ciricillo SF, Weinstein PR (1989) Foramen magnum syndrome from pseudogout of the atlanto-occipital ligament. Case report. J Neurosurg.71(1):141-3.
  3. Doherty M, Dieppe P (1988) Clinical aspects of calcium pyrophosphate dihydrate crystal deposition. Rheum Dis Clin North Am.14(2):395-414.
  4. Fenoy AJ, Menezes AH, Donovan KA, Kralik SF (2008) Calcium pyrophosphate dihydrate crystal deposition in the craniovertebral junction. J Neurosurg Spine.8(1):22-9.
  5. Kohn NN, Hughes RE, Mc CD, Jr., Faires JS (1962) The significance of calcium phosphate crystals in the synovial fluid of arthritic patients: the "pseudogout syndrome". II. Identification of crystals. Ann Intern Med.56:738-45.
  6. Lam HY, Cheung KY, Law SW, Fung KY (2007) Crystal arthropathy of the lumbar spine: a report of 4 cases. J Orthop Surg (Hong Kong).15(1):94-101.
  7. Muthukumar N, Karuppaswamy U (2003) Tumoral calcium pyrophosphate dihydrate deposition disease of the ligamentum flavum. Neurosurgery.53(1):103-8; discussion 8-9.

Contributed by Gerald F. Reis MD, PhD, Arie Perry MD

International Society of Neuropathology