ABSTRACT
A dromedary or humped kidney, is a normal variant contour of the left kidney seen in about 2% of patients (Figure 1); it is rarely seen on the right kidney. ‘An appropriate designation for this morphology would be the term, dromedary left kidney.’ 1 This term and the normal variant it describes was discussed in a 1962 report from the University of Miami and Mercy Hospital, by Benedict Harrow and Jack Sloane’. They studied 1000 consecutive excretory urograms in adults, noting the ‘peculiarity’ in 23 patients. They had recognized the humped kidney for several years but stated it was ‘not until nephrography became more routine during intravenous urography [rhat] this entity [could] be more clearly defined.’ They acknowledged Johan Frimann-Dahl’s 1961 paper as the only other publication to address this deformity. He reported a 10% prevalence in nearly 6000 cases and attributed the contour deformity to prolonged splenic pressure on the renal surface. Harrow and Sloane’ found no relationship with the splenic shadow. The dromedary hump should simply be recognized as a normal variant and not mistaken for a renal mass lesion. (See Beak sign.) ‘Arrows point to the humped portion of a typical triangular-shaped left kidney visualized during intravenous urography.’ Reprinted from Harrow and Sloane’. The dromedary or humped left kidney. <italic>Am. J. Roentgenol.,</italic> 1962, 88, 144–52, with permission of the ARRS https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003076568/34c29fd5-5662-4e8f-b58c-badd7fa5d724/content/fig30_1_B.jpg"/>
