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Extraosseous bone formation in the renal pelvis.
Lubna Samad1, Mohammad Arif, Zafar Zaidi
1Kidney Center Postgraduate Training Institute, Karachi, Pakistan.
The Journal of Urology
|September 18, 2007
Summary
Metaplastic bone formation in the renal pelvis, though rarely reported, was observed in 3.4% of patients undergoing percutaneous nephrolithotomy. Recognition of this extraosseous bone is crucial for patient management and prognosis.
Area of Science:
- Nephrology
- Urology
- Pathology
Background:
- Extraosseous bone formation in the renal pelvis is a rare finding.
- Its pathogenesis and clinical significance are not well understood.
Purpose of the Study:
- To evaluate the frequency and characteristics of metaplastic bone formation in the kidneys of patients undergoing percutaneous nephrolithotomy.
Main Methods:
- Retrospective analysis of 621 patients who underwent percutaneous nephrolithotomy between 1997 and 2006.
- Detailed clinical, radiographic, and histopathological evaluation of 21 cases with observed metaplastic bone.
Main Results:
- Metaplastic bone was identified in 21 patients (3.4%), predominantly in the left kidney.
- Radiographically, a characteristic halo appearance was noted in 77% of cases.
- Histopathology revealed varying compositions of woven and trabecular bone with associated marrow elements.
Conclusions:
- Metaplastic bone in the renal pelvis, while uncommon, appears relatively frequently in this patient cohort.
- Early recognition is vital for appropriate management and prognosis.
- Further research is needed to elucidate the etiology of this phenomenon.
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