A case report of a calyceal diverticulum in a specialist hospital in Rivers State, South-South Nigeria: Computed tomography finding

Calyceal diverticulum (la) is a rare outpouching or eventrations of the upper collecting system lying within the renal parenchyma. These outpouchings are lined by transitional cell epithelium and they communicate with the main collecting system via a narrow channel which allows for passive filling with urine. Calyceal diverticulum was first described in 1841 by Rayer in ‘’Traitments des maladies des reins.’’. Thought to be either cyst or hydronephrosis, he used the term kyste urinaire to describe his finding of intrarenal urine- containing cavities that communicate with calyces. This disease entity is found in 0.21% to 0.6% of intravenous urogram (IVU) performed in adults, with a similar prevalence in children. The disease process affects women more than males. No predilection towards a particular side of the body. Studies have shown that they are most likely congenital in origin than acquired. Also, the similarity in incidence for both adults and children is consistent with an embryologic etiology.  Some other authors came up with several other names depending on the location of the cyst, but Prather coined the word calyceal diverticulum which is what is been used today. Sometimes a misdiagnosis of  hydronephrosis, parapelvic or peripelvic cyst  is made especially on ultrasound and so a crossectional imaging modality such as computed axial tomography is invaluable in making proper diagnosis. Our objective is to highlight the possibility of occurrence of a symptomatic calyceal diverticulum in a child and also to emphasize the use of computed axial tomography in the proper diagnosis of the disease. In this case we present a 14year old female patient with a 3month history of right upper abdominal swelling with associated loin pain. A diagnosis of? Hydronephrosis was made on ultrasound scan, but no obvious cause of obstruction was identified.