Which spleen anomaly is characterized by the inferior portion located posterolateral to the upper pole of the left kidney and can mimic a mass?

Which spleen anomaly is characterized by the inferior portion located posterolateral to the upper pole of the left kidney and can mimic a mass?

• A. Accessory spleen
• B. Wandering spleen
• C. Retrorenal spleen
• D. Splenosis

Answer: (C)

A retrorenal spleen is a spleen variant where part of the organ sits behind the left kidney, with the inferior portion located posterolateral to the upper pole of the kidney. Because this retroperitoneal position can create a mass-like appearance on imaging, it can be mistaken for a renal or adrenal mass if its splenic nature isn’t recognized. This is the best answer because the description specifically matches the retroperitoneal place of the spleen behind the kidney, rather than other spleen anomalies. An accessory spleen is usually a small nodule near the splenic hilum; a wandering spleen is displaced and mobile within the abdomen; splenosis involves multiple splenic implants after trauma. To confirm retrorenal spleen, look for continuity with splenic tissue and typical splenic vascular supply on imaging rather than isolated nodules or displaced nodules.

A retrorenal spleen is a spleen variant where part of the organ sits behind the left kidney, with the inferior portion located posterolateral to the upper pole of the kidney. Because this retroperitoneal position can create a mass-like appearance on imaging, it can be mistaken for a renal or adrenal mass if its splenic nature isn’t recognized.

This is the best answer because the description specifically matches the retroperitoneal place of the spleen behind the kidney, rather than other spleen anomalies. An accessory spleen is usually a small nodule near the splenic hilum; a wandering spleen is displaced and mobile within the abdomen; splenosis involves multiple splenic implants after trauma. To confirm retrorenal spleen, look for continuity with splenic tissue and typical splenic vascular supply on imaging rather than isolated nodules or displaced nodules.