Preoperative imaging of parathyroid glands with technetium-99m-labelled sestamibi and iodine-123 subtraction scanning in secondary hyperparathyroidism.

BACKGROUND: Parathyroidectomy is unsuccessful in 10-30% of uraemic patients operated on for secondary hyperparathyroidism. We investigated the usefulness of preoperative radionuclide imaging, with simultaneous recording of the distribution images of iodine-123 and technetium-99m-labelled sestamibi. METHODS: 11 patients with secondary hyperparathyroidism underwent prospective imaging and parathyroidectomy. Plasma concentrations of intact parathyroid hormone (PTH) were measured in all patients before and 6 months after subtotal parathyroidectomy. FINDINGS: Preoperative scanning showed 42 hot-spots suggesting enlarged parathyroid glands. 45 glands were discovered at surgery, and the parathyroidectomy was deemed successful in ten patients. Among the latter, one patient had a supernumerary parathyroid gland detected by scanning and resected from the left thymus. Another patient showed ectopic uptake corresponding to a large parathyroid gland in the upper mediastinum, and another had a parathyroid gland well above the thyroid. No false-positive scan findings were documented. In the patient for whom parathyroidectomy failed, preoperative scanning suggested five enlarged parathyroid glands, though the surgeon found only four glands, in their normal positions. Hyperparathyroidism persisted (intact PTH 527 ng/L, 6 months after surgery). A second scan confirmed the preoperative scan, showing a fifth parathyroid gland in the middle of the right thyroid lobe. INTERPRETATION: Simultaneous recording of 99mTc-sestamibi and 123I improved the imaging of parathyroid glands in secondary hyperparathyroidism. The technique can identify ectopic and supernumerary parathyroid glands.

Secondary hyperparathyroidism: detection with I-123-Tc-99m-Sestamibi subtraction scintigraphy versus US.

PURPOSE: To compare iodine-123-technetium-99m-sestamibi subtraction scintigraphy with ultrasonography (US) for detection of parathyroid abnormalities in uremic patients with secondary hyperparathyroidism. MATERIALS AND METHODS: Fourteen adult uremic patients with severe secondary hyperparathyroidism underwent subtraction scintigraphy before total or subtotal parathyroidectomy. Subtraction scintigrams were acquired with a double-energy-window technique. US was performed with high-frequency transducers and standard methods. RESULTS: 1-123-Tc-99m-sestamibi subtraction scintigraphy correctly demonstrated 41 of 50 surgically confirmed enlarged parathyroids; US demonstrated 27. Sensitivity for detection of hyperplastic glands was 82% for scintigraphy and 54% for US. Scintigrams were correct in seven patients, and US scans were correct in five. Scintigraphy demonstrated all four enlarged parathyroids in six of 12 patients who were to undergo first surgery, whereas US demonstrated all four enlarged glands in three of the 12 patients. Gland weight was correlated with likelihood of detection with either method. Glands undetected at scintigraphy were significantly (P < .01) smaller (mean weight, 257 mg) than those undetected at US (mean weight, 467 mg). CONCLUSION: I-123-Tc-99m-sestamibi subtraction scintigraphy is efficient for detection of enlarged parathyroid glands in uremic patients with secondary hyperparathyroidism and is more sensitive than US.

Suppression of HLA-specific alloantibodies by high-dose intravenous immunoglobulins (IVIg). A potential tool for transplantation of immunized patients.

Renal transplantation in patients presenting end-stage renal failure can be hampered by the presence of alloantibodies against HLA antigens. In 4 out of 5 patients with HLA-specific alloantibodies waiting for a renal allograft, treatment with high-dose i.v. Ig resulted in a prolonged suppression (over 3 months) of most of the panel-reactive anti-HLA antibodies (PRA). Intravenous polyclonal human Ig (IVIg) and F(ab')2 fragments from IVIg inhibited the binding of patients' plasma and IgG fractions to peripheral blood lymphocytes from normal donors as well as their cytotoxicity, suggesting that the in vivo effect of IVIg was mediated by the presence, in the IVIg preparation, of anti-idiotypes directed against idiotypes borne on the anti-HLA antibodies. Thus, treatment with IVIg can be a valuable tool toward the transplantation of immunized patients.

[Pyelonephritis and kidney transplantation]. / Pyélonéphrite et transplantation rénale.

In immunocompromised subjects pyelonephritis is not more frequent than in healthy subjects and has the same clinical presentation. This is not true for kidney transplant recipients, in whom the physician is faced with fever of unknown origin. However, diagnosis of urinary tract infection is soon made by dipstick and confirmed by the laboratory finding of leucocyturia and bacteriuria. Degradation of renal function indicates that the renal tissue is infected. Treatment must be immediate and prolonged during four weeks. Return to normal renal function is then the rule.