Scanning electron microscopy and x-ray diffraction studies of human bone oxalosis

Area of Science:

• Bone pathology
• Crystal deposition disease
• Nephrology

Background:

• Chronic uremic hemodialysis is associated with secondary hyperparathyroidism.
• Bone complications are common in patients with chronic kidney disease.
• Understanding the composition of bone abnormalities is crucial for patient management.

Observation:

• Postmortem scanning electron microscopy revealed abnormal rounded formations in human phalanges.
• These formations exhibited a radial rosette-like crystalline pattern in both diaphyseal and epiphyseal regions.
• Fan-shaped configurations were observed as individual or aggregated crystalline deposits within bone trabeculae.

Findings:

• X-ray diffraction analysis identified predominant calcium oxalate monohydrate (whewellite) with hydroxyapatite traces.
• Oxalate titration confirmed 25% oxalate content, equating to 45% whewellite by weight.
• These findings indicate significant oxalate deposition in the bone structure.

Implications:

• This study highlights a potential mechanism for bone disease in uremic patients.
• Calcium oxalate crystal deposition may contribute to skeletal fragility and pain.
• Further research is needed to explore diagnostic and therapeutic strategies for oxalate bone disease.