Werdnig Hoffmann Disease

Spinal Muscular Atrophy or Werdnig-Hoffmann disease is also called as SMA1 or spinal muscular atrophy 1. This condition is inherited in an autosomal recessive manner. Degeneration of the nerve cells in the lowest region of the brain and degeneration of specific motor neurons (nerve cells that transmit nerve impulses from brain or spinal cord to the muscles) in the spine lead to muscle weakness. Slowly chewing and breathing also become a challenge. The lower limbs are generally weaker when compared to the upper limbs. These motor neurons are associated with activities such as crawling, walking, sitting up and controlling head movement.

As this condition leads to muscle weakness, kids born with this syndrome are unable to sit up without external support. Amongst the different types of spinal muscular atrophy, Werdnig-Hoffmann disease is the most severe. SMA1 is classified into 3 subgroups depending on the clinical signs and the period of onset.

Type I: Severe weakness since birth, head control is never achieved. Such children are mostly unable to support their head or sit unassisted. Choking and gagging occurs while breathing and swallowing.

Type II: Onset of weakness within 2 months from birth, head control is not achieved.

Type III: Onset of weakness after neonatal period however head control is achieved. A few children may be able to sit up with the help of external support.

Type IV: This type of spinal muscular atrophy occurs after the age of 30. There might be muscle weakness and tremors. In most cases, only the proximal muscles or those closest to the center of the body are affected. There might be involuntary muscle contractions, limb cramps and protrusion of abdomen.

There is no cure for Werdnig-Hoffmann disease and it is a fatal type disorder. The management of this condition could include support from speech therapy, occupational therapy, physiotherapy, palliative medical care and respiratory medicine.