[Crystalline microstructure and microanalysis of gallstones in childhood and adolescence]

To determine the crystalline structure and chemical composition of gallstones in children and adolescents. Design of the studyA simple descriptive study was performed in 21 gallstones from pediatric patients with chronic cholecystitis who underwent elective cholecystectomy. Only two patients had an underlying disease that could explain the presence of gallstones. Crystalline structure was determined by X-ray diffraction and visualization with scanning electron microscopy. Emission and atomic absorption spectroscopy were used to study composition. An X-ray-dispersion energy spectroscope joined to the microscope was used to confirm the crystalline composition of some of the areas examined with the microscope.

Bilirubinate and calcium carbonate predominated in the crystalline composition, demonstrating the pigmented appearance of idiopathic gallstones. Cholesterol was a secondary element. Microanalysis confirmed calcium as a fundamental constituent of gallstones irrespective of age. Other elements, such as sodium, potassium, magnesium and manganese, etc., were detected.

The present study confirms the pigmented character of idiopathic gallstones in childhood. The high levels of calcium carbonate and bilirubinate, despite a lack of evidence for any risk factors for the formation of bilirubinate, was striking. Calcium was the most predominant element of the calculi.