Acromegaly is an abnormal development of the foot or toes into malformed tissue due to a condition such as congenital acromegaly, which causes the patient’s feet to be larger than normal. The causes of this condition are also complex. The main etiology is a local excess of growth hormone and lack of growth inhibitory factors during embryonic growth, and mutations in transfer factors are also associated with its occurrence, but the exact pathogenesis is not yet well understood. So, how is the differential diagnosis of megaloblastic foot? The following is the differential diagnosis of giant foot: 1, foot deformity: foot deformity refers to abnormal foot shape or structure, the normal human foot shape is maintained by the relative proportion of the external and internal muscles to maintain its balance, some congenital or other disease-based causes can cause foot deformity. 2, mortar and pestle finger (toe): finger (toe) end of the soft tissue thickening like bulge expansion, arch-shaped elevation, nail longitudinal ridge and transverse ridge highly curved, the surface is glassy, called pestle finger (acropachy.clubbingfinger). Also known as faded fingers. In healthy people, the angle between the nail and the skin around the nail on the lateral side of the end of the finger is 160 degrees, and with the occurrence of clubbing finger, this angle can gradually become larger to 180 degrees and above. When the nail root is pressed, there can be a distinct elasticity and pressure pain. The color of the end of the finger varies with the occurrence of seedy fingers in different diseases. In the case of congenital heart disease, the end of the finger is often purple-black, the nail arc is reddish-brown, the capillaries in the nail bed are increased, and the blood flow to the end of the finger is increased. In patients with pulmonary disease, the ends of the lamellar fingers are dry and unsmooth, yellowish-white, and the vascular hyperplasia is not significant. The work-like finger (toe) is a more common symptom of certain diseases in internal medicine. 3, parallel fingers (toe) deformity: the so-called parallel toes (fingers) deformity refers to five toes (fingers) between the two or two or more adhered to each other without independent separation, is found at birth in the congenital anomaly. 4, giant finger (toe): giant finger (toe) syndrome is a congenital malformation characterized by an increase in the size of the fingers or toes, the incidence of congenital malformations in the extremities is very low, about 0.9%.