A hemoglobin level of 10 is definitely anemic and could be the result of iron deficiency or a thalassemia, beta or alpha. When the MCV is below 60, it is rarely iron deficiency and more likely a result of thalassemia. The high RDW leads me to think that it may be alpha thalassemia that is involved rather than iron deficiency, because it would probably be a bit higher if due to iron, although a combination of alpha and beta thal can also show a high RDW. The electrophoresis results, along with these results may provide a diagnosis. But because alpha thal can be very difficult to diagnose, a DNA analysis may also be necessary.
Again. I would suggest stopping iron supplements until you know more. Folic acid is a must. I would also like to ask if he has been exposed to any chemicals like what is found in moth balls or any chemicals that give off fumes. Also, has he ever eaten fava beans? Does his abdomen seem to be swollen or enlarged? These are all clues to alpha thal diagnosis. Certain chemicals, drugs and beans like fava beans can set off hemolytic crisis that can cause illness.
Test results can vary a bit. You've mentioned that his MCV was always low. Has it always been in this range, below 60?
I don't want to speculate too much, and partly because test results can vary from lab to lab, and with a bit higher MCV and a higher RDW and lower RBC, it could be iron deficiency. If these readings are accurate, it is very unlikely to be related to iron, it does look more like some form of thalassemia. If these readings are accurate and have been consistent, HbH disease may be a possibility. This is a three gene deleted alpha thal that can vary greatly in symptoms. In very serious case, transfusion may be required. I do feel that since his hemoglobin level is around 10, that if it is HbH it will not be the more serious variety. Folic acid is the main treatment. I would almost totally rule out the possibility of any severe form of beta thalassemia, although as I mentioned, there is some possibility of being a carrier for both alpha and beta.
I have outlined some possibilities and you should not assume anything at this point, but it will help if you have knowledge of the various possible outcomes. I know you were nervous about seeing the hematologist, but an accurate diagnosis is absolutely essential to make sure that the treatment and counseling is appropriate for the condition.