Bochdalek hernias associated with intrathoracic kidney: A case report and systematic review of outcomes including renal function

Abstract

Background: An intrathoracic kidney is a very rare form of ectopic kidney. Though increasingly recognized in the literature, impact on renal function is less well described. We report the case of a 67-year-old South Asian gentleman who presented with intrathoracic kidney and chronic kidney disease. We carried out a systematic review of the available literature on intrathoracic kidney, in order to characterize the typical clinical features, and describe likely clinical course and possible renal and extra-renal complications associated with this form of ectopia.

Materials and methods: A structured search using PubMed identified all relevant published case reports from 1988 to 2018, with search restricted to papers in English, and to adult cases only (> 18 years of age). 124 records were identified, and after screening for eligibility, 34 case reports were analyzed.

Results: Median age was 53.5 years, with no gender predominance. 68% (27/34) of cases were symptomatic. 29% (10/34) had a significant complication associated with their intrathoracic kidney, with 3 cases with either documented chronic or end-stage kidney disease. 26% (9/34) required surgical intervention.

Conclusion: Though previously regarded as a benign entity, results from our systematic review, bearing in mind susceptibility to publication bias, suggests an appreciable risk of symptoms, complications, and in the minority a risk to kidney function. We recommend close biochemical and imaging surveillance of affected patients, with low threshold for intervention in those with renovascular stenosis, reflux, or hydronephrosis.

Keywords: bochdalek hernia; intrathoracic kidney.

Figure 1.. Chest radiograph demonstrating raised hemidiaphragm.

Figure 2.. MRA demonstrating higher position of right kidney than left secondary to a right hemidiaphragmatic hernia containing the right lobe of liver, right kidney, and hepatic flexure. Right kidney 7.4 cm and left kidney 8.4 cm, with no evidence of renal artery stenosis.

Figure 3.. Renal DMSA scan demonstrating split function between right and left kidney (44% : 56%).

Figure 4.. Intrathoracic kidneys and renal outcomes search strategy using PRISMA flowchart.