Hi!
A low MCH indicates low hemoglobin. Low hemoglobin is seen in low iron, kidney diseases, cancers (leukemias, Hodgkin's lymphoma's, myeloma, and other blood cancers), aplastic anemia and myelodysplastic syndromes (bone marrow disorders), cirrhosis of liver, lead poisoning, and in vitamin deficiency. Low hemoglobin can also be due to increased destruction of blood or its components as seen in spleen disorders, sickle cell anemia, thalssemia etc.