Must know points about Vitamin-D and their Deficiencies
Rickets and osteomalacia are different expressions of the same disease , inadequate mineralization of bone .
The inadequacy may be due to defects anywhere along the metabolic pathway for vitamin D : nutritional lack , under exposure to sunlight, intestinal mal – absorption , decreased 25 – hydroxylation ( liver disease , anticonvulsant) and reduce 1alpha hydroxylation ( renal disease ) .
The following factors :
|Decreased vitamin D synthesis||Due to chronic liver disease|
|Decreased nutritional intake of vitamin||In strict vegetarian diet|
|Age and physiology related||Elderly , obese , and institutionalised patients|
|Decreased maternal vitamin D stores||Exclusive breast feeding|
|Malabsorption||Celiac disease , pancreatic insufficiency (cystic fibrosis) , biliary obstruction (biliary atresia)|
|Increased degradation of 25 (OH) D3||Due to intake of drugs such as rifampicin , isoniazid ,anticonvulsant, glucocorticoids.|
CLINICAL FEATURES OF RICKETS :
The infants with rickets may present with tetany or convulsions. Later the parents may notice that there is a failure to thrive , listlessness and muscular flaccidity. Early bone changes are deformity of the skull (craniotabes ) and thinkening of the knees , ankles and wrists from physical overgrowth. Enlargement of the costochondral junctions ( Rickety Rosary) and lateral indentation of the chest ( Harrison’s sulcus ) may also appear.
Distal tibial blowing has been attributed to sitting or lying Cross – legged .
In active rickets there is thickening and Widening of the growth plate , cupping of the metaphysics and , sometimes , bowing of the diaphysis . The metaphysis may remain abnormally wide even after healing has occurred.
Different methods of treating vitamin D deficiency have been advocated, ranging from small doses for a few months to a single mega dose , an approach referred to as Stoss therapy .