Heart block and acute kidney injury due to hyperparathyroidism-induced hypercalcemic crisis.

We describe a patient who presented with multi-system organ failure due to extreme hypercalcemia (serum calcium 19.8 mg/dL), resulting from primary hyperparathyroidism. He was found to have a 4.8 cm solitary atypical parathyroid adenoma. His course was complicated by complete heart block, acute kidney injury, and significant neurocognitive disturbances. Relevant literature was reviewed and discussed. Hyperparathyroidism-induced hypercalcemic crisis (HIHC) is a rare presentation of primary hyperparathyroidism and only a small minority of these patients develop significant cardiac and renal complications. In cases of HIHC, a multidisciplinary effort can facilitate rapid treatment of life-threatening hypercalcemia and definitive treatment by surgical resection. As such, temporary transvenous cardiac pacing and renal replacement therapy can provide a life-saving bridge to definitive parathyroidectomy in cases of HIHC.

Utility of captopril renal scans for detecting renal artery stenosis.

BACKGROUND: Captopril renal scanning (CRS) is commonly recommended as a noninvasive method for detecting renal artery stenosis (RAS), based on performance characteristics determined in research settings. Scant data are available, however, regarding the utility of CRS in clinical practice. METHODS: We evaluated the performance characteristics (sensitivity, specificity, and predictive values) of CRS in a consecutive series of 90 patients who underwent both CRS and renal arteriography within a 6-month period (January 1, 1991, through December 31, 1995) at a university hospital. RESULTS: Among 86 eligible patients (and 169 kidneys), the prevalence of RAS was 43%. The sensitivity of CRS was 74% (95% confidence interval [CI], 62%-83%); the specificity was 59% (95% CI, 49%-69%); the positive predictive value was 58% (95% CI, 47%-68%); and the negative predictive value was 75% (95% CI, 64%-84%). Also, there was evidence of spectrum bias, because the sensitivity and specificity (as well as the positive and negative predictive values) were different for groups with and without vascular disease. CONCLUSIONS: The results of CRS were substantially worse in a clinical practice setting than previously reported in research settings, despite a similar prevalence of RAS. Captopril renal scanning should not be used as an initial screening test for diagnosing RAS, even among patients with high clinical likelihood of disease.