Pompe Disease in Infants

In infants, Pompe disease is a life-threatening condition that affects many parts of the body. However, a severely enlarged heart and resulting heart problems, combined with severe overall muscle weakness (floppy baby appearance) are the characteristic signs of the disease in infants.[1], [2]

See the complete list of signs and symptoms (below)

Signs & Symptoms Overview

This interactive diagram provides an overview of the areas of the body most affected by Pompe disease in infants. Roll over and click the illustration or text labels to see more information.

Disease Progression

When infants are affected by the disease, signs and symptoms usually appear within the first few months of life, sometimes even immediately after birth. Parents may initially notice the baby’s general muscle weakness and difficulty breathing and/or eating.

As the heart and breathing muscles continue to deteriorate, the infant may quickly become gravely ill, even over just a few months. The infant may:[1], [3], [4]

  • Fail to meet developmental milestones such as rolling over and sitting up, and may lose any abilities they have already achieved
  • Fail to gain sufficient weight for their age
  • Develop severe breathing difficulties and frequent lung infections
  • Experience changes in their heart rhythms and usually die from heart and/or breathing failure by the age of 1 year

Comprehensive List of Signs & Symptoms

Following is a complete list of possible signs and symptoms that may appear in infants with Pompe disease. Note that not every patient will necessarily show these signs or experience all these symptoms.

Muscle & Movement Problems

Severe muscle weakness, resulting in:

  • An overall “floppy” appearance because of poor muscle tone
  • Head lag, meaning that the baby’s head falls back because neck and other muscles are too weak to support its weight
  • Legs fall outward into a “frog-like” position because of weak muscles
  • Difficulty sucking, swallowing, and/or generally feeding because of weakened mouth, tongue, and facial muscles
  • Failure to meet developmental milestones such as rolling over, sitting up, crawling, and walking, or loss of abilities already achieved[1], [3], [4]

Heart Problems[3]

  • A greatly enlarged heart, resulting from excess glycogen building up in heart muscle cells, causing them to enlarge
  • Heart rhythm changes, caused by weakened heart muscle that cannot function properly
  • Heart failure, often resulting in early death

Find out about the importance of monitoring heart health in infants with Pompe disease 

Breathing & Respiratory Problems

  • Difficulty breathing, as the diaphragm and other surrounding muscles used for breathing weaken, sometimes causing sleeping problems
  • A tendency to develop respiratory infections, because weak muscles make it difficult to breathe deeply enough to clear mucus out of the lungs
  • Respiratory failure, when the body stops breathing on its own, which can lead to early death

Infants with Pompe disease eventually need to use a ventilator, a special machine that helps them breathe when they can no longer do so on their own.

Feeding & Digestion Problems

  • An enlarged and sometimes protruding tongue, which can interfere with feeding
  • Digestive difficulties resulting in vomiting/regurgitation
  • Failure to thrive or gain weight as rapidly as other babies the same age because of feeding difficulties

For severely underweight infants, tube feeding may be used to provide liquid food directly to the digestive system.

Other Signs

  • A slightly enlarged liver
  • Higher than normal levels of certain substances in the blood[1], [4], [5]


  1. Hirschhorn, Rochelle and Arnold J. J. Reuser. Glycogen Storage Disease Type II: Acid Alpha-glucosidase (Acid Maltase) Deficiency. In: Scriver C, Beaudet A, Sly W, Valle D, editors. The Metabolic and Molecular Bases of Inherited Disease. 8th Edition. New York: McGraw-Hill, 2001. 3389-3420.
  2. Slonim AE, Bulone L, Ritz S et al. Identification of two subtypes of infantile acid maltase deficiency. J Pediatr 2000 Aug;137(2):283-5.
  3. Kishnani PS, Hwu W-L, Mandel H, Nicolino M, Yong F, Corzo D. A retrospective, multinational, multicenter study on the natural history of infantile-onset Pompe disease. J Pediatr 2006 148:671-676.
  4. Van den Hout HMP. The natural course of infantile Pompe’s disease: 20 original cases compared with 133 cases from the literature. Pediatr 2003 Aug;112(2):332-340.
  5. Kishnani PS, Steiner RD, Bali D et al. Pompe disease diagnosis and management guideline. Genet Med 2006 8:267-88.

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