The use of gallium-67 scintigraphy in the diagnosis of acute interstitial nephritis

• Published in: Clinical kidney journal Vol. 9; no. 1; pp. 76 - 81
• Main Authors: Graham, François, Lord, Martin, Froment, Daniel, Cardinal, Héloise, Bollée, Guillaume
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.02.2016
• Subjects: Tubulointerstitial Disease Diagnosis; gallium scintigraphy; interstitial nephritis
• ISSN: 2048-8505; 2048-8513
• DOI: 10.1093/ckj/sfv129

Gallium-67 scintigraphy has been suggested as a noninvasive method to diagnose acute interstitial nephritis (AIN). However, its diagnostic performance and usefulness remain controversial. We retrospectively reviewed the charts of 76 patients who underwent gallium-67 scintigraphy for a suspicion of AIN. Patients were classified based on kidney biopsy and/or clinical probability of AIN. Gallium-67 scintigraphy results were reinterpreted blindly using both posterior planar and single photon emission computed tomography (SPECT) imaging. Intensity of radioisotope uptake in the kidney was graded from 0 to 5. The diagnosis of AIN was confirmed in 23 patients and excluded in 44. Nine patients with an uncertain diagnosis were excluded from subsequent analysis. A gallium-67 kidney uptake cutoff of 1 gave a negative predictive value of 100%, whereas a cutoff of 5 had an excellent specificity and positive predictive value for the diagnosis of AIN. When using a cutoff of 3, which had previously been used in the literature, we obtained a sensitivity of 61% and a specificity of 75% with posterior planar imaging. The results of both SPECT and posterior planar imaging modalities were comparable. Gallium-67 scintigraphy may be of interest in patients with a clinical suspicion of AIN, especially in those who are unable to undergo kidney biopsy. However, results need to be interpreted with caution and depend on the intensity of gallium-67 kidney uptake.