Hypercalcaemia and acute renal failure after major burns: An under-diagnosed condition.

BACKGROUND: Hypercalcaemia has been shown to occur in about 20% of patients with major burns requiring prolonged intensive care unit (ICU) treatment, and it may be associated with renal failure. Having observed the early onset of hypercalcaemia, the study aimed to determine the frequency and timing of this condition in a European patient cohort. METHODS: A retrospective cohort study on a prospectively collected, computerised database of the 225 burn-injury ICU admissions between 2001 and 2007 was undertaken. The inclusion criteria included: burns >20% of the body surface area (BSA) or in-hospital stay >20 days. Hypercalcaemia was defined as an ionised plasma calcium (Ca(2+)) concentration >1.32 mmol l(-1) (or total corrected calcium=[Ca]c>2.55 mmol l(-1)). Four emblematic cases are reported in this article. RESULTS: A total of 73 patients met the inclusion criteria (age: 13-88 years, burns: 12-85% BSA): of these, 22 (30%) developed hypercalcaemia. The median time to the first hypercalcaemia value was 21 days. Only 11 patients had both high Ca(2+) and elevated [Ca]c (which remained normal in others). The risk factors of the disorder were burned surface (p=0.017) and immobilisation (fluidised bed use: p<0.05, duration: p=0.02) followed by burned BSA. Acute renal failure tended to be more frequent in hypercalcaemic patients (five (23%) vs. three (6%): p=0.11), while mortality was not increased. The disorder resolved with hydration and mobilisation in most cases: pamidronate was successful in three cases that were most severe. CONCLUSION: Hypercalcaemia and associated acute renal failure occur more frequently and earlier than previously reported. Determining the ionised Ca rather than the total Ca with albumin correction enables earlier detection of hypercalcaemia. Bisphosphonates are an effective treatment option in controlling severe hypercalcaemia and preventing bone loss.

Innappropriate renin secretion unmasked by captopril (SQ 14 225) in hypertension of chronic renal failure

Captopril (SQ 14 225), an orally active inhibitor of angiotensin-converting enzyme, was given to 7 hypertensive patients with chronic renal failure whose plasma-creatinine ranged from 1.5--7.4 mg/dl; whose plasma-renin activity was normal; whose hypertension was not controlled by previous therapy consisting in 5 patients of three or more antihypertensive drugs; and whose blood-pressures averaged 176/111 +/- 11/3 mm Hg. Inhibition of converting enzyme by oral captopril, 200 mg twice daily, reduced blood-pressure to 156/100 +/- 9/5 mm Hg. 5 patients needed additional treatment by frusemide 40--250 mg/day orally. With this combined regimen the blood-pressure of all patients averaged 126/85 +/- 4/3 mm Hg after 8 +/- 2 weeks of captopril. The drug was well tolerated. These results suggest that inhibition of angiotensin-converting enzyme with or without sodium depletion is an efficient treatment for hypertension associated with chronic renal failure. It appears that although renin levels in patients with this condition may be "normal", they are inappropriate in relation to the subtle degree of sodium retention that occurs with this disorder.