Impaired renal function in a patient treated for psychiatric problems for many years.
Both patients were treated with lithium for many years causing so called lithium kidneys.
The predominant form of chronic renal disease associated with lithium therapy is a chronic tubulointerstitial nephropathy. The image findings of renal disease that distinguish patients treated with lithium from other renal cystic disorders are the presence of distal tubular dilatation and microcysts. These cysts are present in 33%-62% of patients undergoing lithium therapy. They are localized in both the cortex and the medulla. In general, they do not exceed 1-2 mm in diameter. Lithium-associated kidney microcysts are usually echogenic on ultrasound examination because these cysts are lined by cuboidal epithelial cells in a stroma, which is surrounded by fibrosis. This surrounding fibrosis dominates the ultrasound image and appears as echogenic foci. CT and MRI demonstrate the usual appearance of cysts except the size is usually in 1-2mm range and no contrast enahancement is present.