When does this condition occur?

Question

a child, with high serum phosphate levels, and normal calcium levels has presented with the following- distorted face, stunting of growth.

When is this condition most likely to occur?

Answer 1

Fanconi syndrome and Vitamin D resistant rickets first came to mind, but both are associated with low serum phosphorus. In DiGeorge syndrome, the calcium is low.

Hyperphosphatasia is rather rare.

Disorders of the parathyroid glands may cause this, but I cannot recall a specific disease. I will probably be embarrassed when someone comes up with an obvious answer.

Answer 2

Is the child in renal failure? That may be the cause. If not...

You'd need to see a urinalysis to find out if the high serum phosphate is from high phosphate load or from increased renal tubular reabsorption of phosphate. High phosphate load indicated by urine phosphate >1000mg/day, can be either exogenous (phosphate enemas, laxatives, etc) or endogenous (neoplasms or some form of tissue breakdown). Increased renal tubular reabsorption of phosphate, indicated by urine phosphate <1000mg/day, can be caused by may things including, but not limited to: parathyriod hormone deficiency or resistence, acromegaly, thyrotoxicosis, sickle cell anemia, etc. All of this is pretty much strictly in terms of of having high serum phosphate, so you'd have to narrow it down to something that also has a normal serum calcium which I think could be any of those things I've stated based on nutritional state. Because its associated with bone malformation it probably has something to do with the parathyroid gland as another poster stated.