Rheumatology and Rehabilitation, 1978, 17, 6
ACUTE PSEUDOGOUT ATTACK FOLLOWING PARATHYROIDECTOMY BY M. NAHIR, Y. SCHARF, J. G. BROOK AND B. SEGAL
of acute pseud ogout (PG) following parathyroidectomy are rare, and only a few reports have appeared in the literature (Bilezikian, Anerbach and Conner, 1973; O'Duffy, 1976). To the best of our knowledge, calcium levels in the synovial fluid of these post-parathyroidectomy patients have not been reported. Our case is presented in order to throw further light on the understanding of the mechanism underlying these attacks. EPISODES
CASE REPORT A 62-year-old woman was evaluated for hypercalcaemia discovered on routine blood analysis. She had never been subject to any arthritic discomfort. Serum calcium 3.3-3.5 mmol/1 (13.2-14.0 mg/100 ml) bicarbonate 20 mEq/1 and chloride 106 mEq/1. Sodium, potassium and uric acid levels were normal. Hyperparathyroidism was diagnosed, and a 12 g parathyroid adenoma successfully removed. On the fourth post-operative day, the serum calcium was 2.1 mmol/1 (8.4 mg/100 ml). On the following day she complained of severe pain in both knees and developed a frank arthritis. The patient's temperature was 38.5 °C. Radiography showed chondrocalcinosis in both knees. The serum calcium was 2.25 mmol/1 (9.0 mg/100 ml), phosphorus 1.1 mmol/1 (2.7 mg/100 ml), bicarbonate 26 mEq/1 and chloride 98 mEq/1. Serum sodium, potassium and uric acid were normal. The synovial fluid aspirate was turbid, sterile and contained weakly positively birefringent intraleucocytic crystals. The synovial fluid calcium level was 1.28 mmol/1 (5.1 mg/100 ml). Dramatic clinical improvement followed the intra-articular injection of methyl prednisolone. COMMENT The mechanism of acute PG attacks following parathyroidectomy is not completely understood. The relative hypocalcaemia subsequent to parathyroid removal seems to be an important factor and the attacks appear to occur at the nadir of the serum calcium level (O'Dufly, 1976). The reduction of serum calcium is followed by a fall in the synovial fluid calcium level, and there is some evidence that this would enhance 'crystal shedding', whereby preformed articular deposits of calcium pyrophosphate crystals would be released into the synovial fluid, and thus precipitate an acute attack (McCarty, 1976). Bennett et al. (1976), by lowering synovial calcium concentration in a joint with chondrocalcinosis by means of magnesium or EDTA lavage, succeeded in producing such an acute attack. O'Dufiy reported two patients with hyperparathyroidism who developed acute PG attacks following medical reduction of their serum calcium. The fact that a low synovial fluid calcium was confirmed in our patient is certainly compatible with the theory of 'crystal shedding'. Russell's observation of low synovial fluid calcium level patients with acute PG attacks who had not undergone parathyroidectomy is also consistent with this mechanism (Russell, Bisaz and Fleish, 1970). Hyperchloraemic acidosis is common in patients with hyperparathyroidism. Parathyroidectomy results in a rapid change towards normal values. The role of this acid-base Accepted for publication May 1977.
Downloaded from http://rheumatology.oxfordjournals.org/ at University of California, San Francisco on February 25, 2015
The B. Shine Department of Rheumatology and Department of Medicine B, Rambam Medical Center and Aba Khoushi School of Medicine, Haifa, Israel
NAHIR ET AL.: PSEUDOGOUT AFTER PARATHYROEDECTOMY
7
change, which occurs concomitantly with the relative hypocalcaemia, in the pathogenesis of acute attacks of PG has yet to be elucidated. REFERENCES
R. M., LEHR, J. R. and MCCARTY, D. J. (1976) "Crystal Shedding and Acute Pseudogout". Arthritis Rheum. 19, 93. BILEZKIAN, J. P., ANERBACH, G. D. and CONNOR, T. B. (1973) "Pseudogout after Parathyroidectomy". Lancet, i, 445. O'DUFFY, J. D. (1976) "Clinical Studies of Acute Pseudogout Attacks". Arthritis Rheum. 19, 349. MCCARTY, D. J. (1976) "Calcium Pyrophosphate Dehydrate Crystal Deposition Disease". Arthritis Rheum. 19, 275. RUSSELL, R. G. G., BISAZ, S. and FLEISH, H. (1970) "Inorganic Pyrophosphate in Plasma, Urine and Synovial Fluid of Patients with Pyrophosphate Arthropathy (Chondrocalcinosis or Pseudogout)". Lancet, ii, 899. BENNETT,
Downloaded from http://rheumatology.oxfordjournals.org/ at University of California, San Francisco on February 25, 2015
ACUTE PSEUDOGOUT ATTACK FOLLOWING PARATHYROIDECTOMY BY M. NAHIR, Y. SCHARF, J. G. BROOK AND B. SEGAL
of acute pseud ogout (PG) following parathyroidectomy are rare, and only a few reports have appeared in the literature (Bilezikian, Anerbach and Conner, 1973; O'Duffy, 1976). To the best of our knowledge, calcium levels in the synovial fluid of these post-parathyroidectomy patients have not been reported. Our case is presented in order to throw further light on the understanding of the mechanism underlying these attacks. EPISODES
CASE REPORT A 62-year-old woman was evaluated for hypercalcaemia discovered on routine blood analysis. She had never been subject to any arthritic discomfort. Serum calcium 3.3-3.5 mmol/1 (13.2-14.0 mg/100 ml) bicarbonate 20 mEq/1 and chloride 106 mEq/1. Sodium, potassium and uric acid levels were normal. Hyperparathyroidism was diagnosed, and a 12 g parathyroid adenoma successfully removed. On the fourth post-operative day, the serum calcium was 2.1 mmol/1 (8.4 mg/100 ml). On the following day she complained of severe pain in both knees and developed a frank arthritis. The patient's temperature was 38.5 °C. Radiography showed chondrocalcinosis in both knees. The serum calcium was 2.25 mmol/1 (9.0 mg/100 ml), phosphorus 1.1 mmol/1 (2.7 mg/100 ml), bicarbonate 26 mEq/1 and chloride 98 mEq/1. Serum sodium, potassium and uric acid were normal. The synovial fluid aspirate was turbid, sterile and contained weakly positively birefringent intraleucocytic crystals. The synovial fluid calcium level was 1.28 mmol/1 (5.1 mg/100 ml). Dramatic clinical improvement followed the intra-articular injection of methyl prednisolone. COMMENT The mechanism of acute PG attacks following parathyroidectomy is not completely understood. The relative hypocalcaemia subsequent to parathyroid removal seems to be an important factor and the attacks appear to occur at the nadir of the serum calcium level (O'Dufly, 1976). The reduction of serum calcium is followed by a fall in the synovial fluid calcium level, and there is some evidence that this would enhance 'crystal shedding', whereby preformed articular deposits of calcium pyrophosphate crystals would be released into the synovial fluid, and thus precipitate an acute attack (McCarty, 1976). Bennett et al. (1976), by lowering synovial calcium concentration in a joint with chondrocalcinosis by means of magnesium or EDTA lavage, succeeded in producing such an acute attack. O'Dufiy reported two patients with hyperparathyroidism who developed acute PG attacks following medical reduction of their serum calcium. The fact that a low synovial fluid calcium was confirmed in our patient is certainly compatible with the theory of 'crystal shedding'. Russell's observation of low synovial fluid calcium level patients with acute PG attacks who had not undergone parathyroidectomy is also consistent with this mechanism (Russell, Bisaz and Fleish, 1970). Hyperchloraemic acidosis is common in patients with hyperparathyroidism. Parathyroidectomy results in a rapid change towards normal values. The role of this acid-base Accepted for publication May 1977.
Downloaded from http://rheumatology.oxfordjournals.org/ at University of California, San Francisco on February 25, 2015
The B. Shine Department of Rheumatology and Department of Medicine B, Rambam Medical Center and Aba Khoushi School of Medicine, Haifa, Israel
NAHIR ET AL.: PSEUDOGOUT AFTER PARATHYROEDECTOMY
7
change, which occurs concomitantly with the relative hypocalcaemia, in the pathogenesis of acute attacks of PG has yet to be elucidated. REFERENCES
R. M., LEHR, J. R. and MCCARTY, D. J. (1976) "Crystal Shedding and Acute Pseudogout". Arthritis Rheum. 19, 93. BILEZKIAN, J. P., ANERBACH, G. D. and CONNOR, T. B. (1973) "Pseudogout after Parathyroidectomy". Lancet, i, 445. O'DUFFY, J. D. (1976) "Clinical Studies of Acute Pseudogout Attacks". Arthritis Rheum. 19, 349. MCCARTY, D. J. (1976) "Calcium Pyrophosphate Dehydrate Crystal Deposition Disease". Arthritis Rheum. 19, 275. RUSSELL, R. G. G., BISAZ, S. and FLEISH, H. (1970) "Inorganic Pyrophosphate in Plasma, Urine and Synovial Fluid of Patients with Pyrophosphate Arthropathy (Chondrocalcinosis or Pseudogout)". Lancet, ii, 899. BENNETT,
Downloaded from http://rheumatology.oxfordjournals.org/ at University of California, San Francisco on February 25, 2015
