Some signs of small red blood cells disease are a very enlarged spleen and other organs and jaundice, according to MedlinePlus and Healthline. One type of small red blood cells disease is thalassemia. There are basically two types: alpha and beta.
Alpha thalassemia is further divided into two types, says Healthline. These are hemoglobin H disease and hydrops fetalis. In hemoglobin H disease, the bones in the patient's jaw, cheeks and forehead may be enlarged. He may also be malnourished. Hydrops fetalis strikes a baby before he is born. Most babies who have hydrops fetalis die soon after birth or are stillborn.
Beta thalassemia has two serious forms. One is Cooley's anemia, and the other is thalassemia intermedia, says Healthline. Cooley's anemia usually affects babies and symptoms present before the child is 2. He is pale, fussy, does not grow properly, has a poor appetite, and is constantly sick with infections. He is also jaundiced and has enlarged organs. This type of thalassemia can be life-threatening, and the child may need to have repeated blood transfusions. Thalassemia intermedia is a not as severe and does not require the patient to have blood transfusions.
Iron deficiency anemia is another disease with red blood cells that are smaller than normal, according to the American Family Physician. The signs of iron deficiency anemia can be brittle nails, pale skin, and a swollen or sore tongue, claims Healthline.