Niemann’s Disease – Pick (Sphingomyelinosis)

What is Niemann’s Disease – Pick (Sphingomyelinosis)?

Niman’s disease – Pick (sphingomyelinosis) (early childhood form). The incidence is 1 case per 100,000 children. The disease was described by A. Niemann in 1914 and in 1922. L. Pick.

Niemann-Pick disease unites a group of sphingomyelolipidosis characterized by sphingomyelin accumulation due to a decrease in the activity of the sphingomyelinase enzyme catalyzing the hydrolysis of sphingomyelin with the formation of phosphorylcholine and ceramide residues.

Causes of Niemann’s Disease – Pick (Sphingomyelinosis)

The basis of the disease is the lack of the enzyme sphingomyelinidase.

Pathogenesis during Niemann’s Disease – Pick (Sphingomyelinosis)

The primary biochemical defect is the deficiency of the enzyme catalyzing the hydrolysis of sphingomyelin; while there is an accumulation and deposition of sphingomyelin and cholesterol in the cells of the reticulo-endothelial system and in the brain. It appears that cholesterol plays a special role as a lipid-orthanizer. providing interaction of lipid molecules. Therefore, the retention of one lipid in the cytoplasm of cells can lead to a secondary increase in other lipids.

Pathological examination revealed a significant increase in the liver, spleen, lymph nodes and the presence of large histiocytic cells with abundant inclusion of sphingomyelin-type fatty substances, as well as sphygmomyelin accumulation in the nerve and glial cells, their demyelination, scarring and fibrosis.

Symptoms of Niemann’s Disease – Pick (Sphingomyelinosis)

The disease begins at the age of 3-5 months with anorexia, vomiting, irritability, then apathy occurs. There is an increase in the liver, spleen and lymph nodes. They become tight, painful. First, there is a halt in general development, then a loss of motor skills. Lost interest in the environment. Hypertonus, less often hypotonia of the musculature, epileptic seizures, reduction of pain sensitivity are also detected. In patients with reduced visual acuity, then blindness and deafness occur. In 20-60% of patients found a cherry spot in the fundus.

There are three main types of Niemann’s disease – Pick – A, B and C, which differ in the time of onset and the severity of neurological and visceral manifestations.

The disease occurs in all ethnic groups, but the frequency of type A is higher among Ashkenazi Jews and is 1: 100.

Type A (classic infantile form, acute neuropathic form) is observed most often. The disease manifests itself after birth and is characterized by a lesion of the internal organs and the central nervous system. Already in 3 months feeding difficulties, hypotrophy are noted, and in 6 months hepatosplenomegaly is detected. As a rule, the liver enlarges earlier than the spleen. Children are exhausted, characterized by a large protruding belly and thin limbs. Of neurological disorders, there is marked hypotonia, oppression of tendon reflexes, lack of response to the environment, stopping of motor development, then loss of already acquired skills. Early hearing is reduced. The skin becomes brownish-yellow due to sphingomyelin. In about 50% of cases, a cherry-red spot is found in the macula of the retina. Corneal clouding, brown staining of the anterior lens capsule are also described. Sick children usually die in the third year of life.

In type B (visceral form, chronic form without involvement of the nervous system), the main clinical manifestations develop later than in type A. Splenomegaly appears at the age of 2-6 years, later the liver and lungs are affected (patients are exposed to frequent respiratory tract infections). Symptoms of lesions absent, on the contrary, in some cases high intellectual abilities are noted. Life expectancy is not reduced.

Type C (subacute, juvenile form, chronic neuropathic form) manifests itself in 1-2 years and is characterized by neurovisceral disorders. At first, hepatosplenomegaly appears (less pronounced as compared with types A and B), cholestasis may occur. Neurological symptoms develop on the background of damage to internal organs, there is marked hypotonia, increased deep tendon reflexes, which are replaced by spastic paralysis, as well as intentional tremor, moderate ataxia, and seizures. Most patients die at the age of 5-15 years.

Diagnosis of Niemann’s Disease – Pick (Sphingomyelinosis)

Laboratory diagnostics is based on the detection in the biopsy material of the lymph node, liver, or spleen spleen. In leukocytes and culture of fibroblasts, a reduction or absence of an enzyme is found.

Differential diagnosis is carried out with other intracellular lipidosis, leukodistrofpiami, hepatitis.

Treatment of Niman’s Disease – Pick (Sphingomyelinosis)

Symptomatic treatment. Some stabilization of the process and improvement of the general condition are observed with the appointment of vitamins, blood transfusion, plasma, the introduction of tissue extracts.

Prevention of Niman’s Disease – Pick (Sphingomyelinosis)

The prevention of Niemann-Pick disease consists in conducting medical genetic counseling and examination in specialized clinics in order to detect heterozygotes for an autosomal recessive gene. Prenatal diagnosis is also carried out: sphingomyelinase activity is determined in amniotic cell culture.