Carpal tunnel syndrome secondary to uraemic tumoral calcinosis

F. Cofan, S. Garcia1, A. Combalia1, J.-M. Segur1 and F. Oppenheimer

Renal Transplant Unit and
1Department of Orthopaedic Surgery, Hospital Clinic, University of Barcelona, Barcelona, Spain

SIR, Tumoral calcinosis is an unusual benign condition characterized by the presence of slow-growing calcified periarticular soft tissue masses composed of calcium salts and usually located around the large joints. There is a primary form (idiopathic or hereditary), but it can also be found in a wide variety of conditions, such as primary hyperparathyroidism, vitamin D intoxication, scleroderma and uraemic tumoral calcinosis [1]. It is usually asymptomatic and nerve compression is rare.

We describe an unusual case of a patient on long-term haemodialysis for chronic renal failure who presented carpal tunnel syndrome (CTS) secondary to extensive uraemic tumoral calcinosis that affected her wrist and hand.

A 25-yr-old woman with chronic renal failure due to systemic lupus erythematosus, who had been receiving chronic haemodialysis since 1989, required medical attention for pain, loss of strength and paraesthesia in the territory of the median nerve of the right hand. Physical examination disclosed several tumours on the right wrist and the proximal part of the palmar surface, of firm consistency and painless when touched. Phalen’s test and Tinel's sign in the right wrist were positive.

Conventional radiographs revealed a lobulated, homogeneous, densely calcified mass on the carpus and the metacarpus of the right hand. Computed tomography (CT) showed a large calcified mass extending through the carpal tunnel to the proximal region of the second, third and fourth metacarpals (Fig. 1Go). Magnetic resonance imaging (MRI) disclosed a mass of 4x3.5 cm occupying the carpal tunnel and the thenar eminence with a low signal density area on T1-weighted sequences and with a well-defined wall.



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FIG. 1.  CT scan shows lobulated calcification extending through the carpal tunnel.

 
Electrophysiological study confirmed compression of the median nerve in the right wrist. Laboratory data showed glucose 6.6 mmol/l, creatinine 875 µmol/l, sodium 136 mmol/l, potassium 5.6 mmol/l, calcium 2.7 mmol/l, phosphorus 2.2 mmol/l, alkaline phosphatase 206 U/l and parathyroid hormone 620 ng/l (normally <60 ng/l). Retrospective evaluation of calcium and phosphorus metabolism showed a very high calcium–phosphorus product (CaxP), which was persistently above 70 (measurements in conventional units), due to hypercalcaemia and uncontrolled hyperphosphataemia of multifactorial aetiology, including prolonged and excessive administration of calcium carbonate/calcitrol, inadequate phosphorus-chelating therapy and severe secondary hyperparathyroidism.

Calcifications in the wrist and thenar region of the right hand were removed by surgery. Microscopy showed numerous calcified masses surrounded by granulation tissue with histiocytes and some multinucleated cells, and tumoral calcinosis was diagnosed. The duration of dialysis was increased, hyperphosphataemia was corrected and calcitriol was suspended, thereby obtaining a reduction in calcium–phosphorus product. Parathyroidectomy was performed. The paraesthesia disappeared in the early period after surgery and electrophysiological data 3 months later were normal. No recurrence of tumoral calcinosis was documented after a 14-month follow-up.

The pathogenesis of uraemic tumoral calcinosis is not well understood. Precipitation of calcium phosphate salts occurs when the solubility of calcium–phosphorus product reaches a critical value (usually CaxP >70). In the past, the most frequent cause of this increase was severe uncontrolled hyperparathyroidism. Nowadays, this increase in calcium–phosphorus product is caused mainly by iatrogenic hypercalcaemia and/or severe hyperphosphataemia of multifactorial aetiology: excessive administration of calcitriol or calcium carbonate, inadequate phosphorus-chelating therapy and insufficient dialysis [2].

The lesion consists of encapsulated, multilobulated masses of variable size, containing a creamy toothpaste-like material. The clinical manifestations are round, progressively growing, periarticular tumours with a firm consistency, usually located around the large joints [3]. Radiographs reveal lobulated, homogeneous, densely calcified periarticular masses with normal joint spaces. CT can disclose the presence of fluid-calcium levels (sedimentation sign) and MRI shows low-signal density on T1-weighted sequences. The radiological characteristics allow tumoral calcinosis to be distinguished from other diseases that produce soft tissue calcification [1]. Treatment of uraemic tumoral calcinosis consists in correction of the factors responsible for the increased calcium–phosphorus product. Surgery is advised when the masses cause symptoms. Renal transplantation or an increase in dialysis may lead to reduction of masses by inducing a negative calcium balance [2].

Nerve compression due to uraemic tumoral calcinosis is uncommon in dialysis patients. We recently described a patient with ulnar nerve compression caused by uraemic tumoral calcinosis in Guyon's canal [4] and another with a giant uraemic tumoral calcinosis in the left elbow with compression of the cubital nerve [5]. In patients undergoing long-term dialysis, the development of CTS is well recognized and, less frequently, cubital nerve compression due to dialysis-related amyloidosis (ß2-microglobulin deposition) occurs [6, 7]. Nevertheless, the development of CTS secondary to tumoral calcinosis is very uncommon. To date, CTS due to idiopathic tumoral calcinosis has been described only in patients without renal disease [8, 9] and no cases have been described in dialysis patients.

In conclusion, uraemic tumoral calcinosis is an uncommon aetiology of secondary CTS that has not been reported in a dialysis patient until now.

Notes

Correspondence to: F. Cofan, Renal Transplant Unit, Hospital Clinic, Villarroel 170, 08036 Barcelona, Spain. Back

References

  1. Steinbach LS, Johnston JO, Tepper EF, Honda GD, Martel W. Tumoral calcinosis: radiologic–pathologic correlation. Skeletal Radiol1995;24:573–8.[ISI][Medline]
  2. Femandez E, Amoedo ML, Borras M, Pais B, Montoliu J. (1993) Tumoral calcinosis in haemodialysis patients without severe hyperparathyroidism. Nephrol Dial Transplantation8:1270–3.
  3. Geirnaerdt MJ, Kroon HM, van der Heul RO, Herfkens HF. Tumoral calcinosis. Skeletal Radiol1995;24:148–51.[ISI][Medline]
  4. Garcia S, Cofan F, Combalia A, Campistol JM, Oppenheimer F, Ramon R. Compression of the ulnar nerve in Guyon's canal by uremic tumoral calcinosis. Arch Orthop Trauma Surg2000;120:228–30.[ISI][Medline]
  5. Cofan F, Garcia S, Campistol JM, Combalia A, Oppenheimer, Ramón R. Ulnar nerve compression—a case of giant uremic tumoral calcinosis. Acta Orthop Scand1997;68:302–9.[ISI][Medline]
  6. Konishiike T, Hashizume H, Nishida K, Inoue H, Moriwaki K. Cubital tunnel syndrome in a patient in long-term haemodialysis. J Hand Surg Br1994;19:636–7.[Medline]
  7. Ullian ME, Hammond WS, Alfrey AC, Schultz A, Molitoris BA. Beta2-microglobulin associated amyloidosis in chronic hemodialysis patients with carpal tunnel syndrome. Medicine (Baltimore) 1989;68:107–15.[ISI][Medline]
  8. Takada T, Fujioka H, Mizuno K. Carpal tunnel syndrome caused by idiopathic calcified mass. Arch Orthop Trauma Surg2000;120:226–7.[ISI][Medline]
  9. Weiber H, Linell F. Tumoral calcinosis causing acute carpal tunnel syndrome. Scand J Plast Reconstr Surg1987;21:229–30.[ISI]
Accepted 9 November 2001





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