Immune defect due to absence of thymus

Other Names: T-lymphocyte deficiency; Thymic aplasia; Nezelof syndrome

A rare primary immunodeficiency with autosomal or X-linked recessive inheritance, characterized by atrophy of the thymus in the absence of other congenital abnormalities, with profound T-cell deficiency, while serum immunoglobulin levels are normal or increased. Patients present with chronic or recurrent infections in infancy including candidiasis, skin, pulmonary and urinary tract infections, chronic diarrhea, and failure to thrive.

Human Thymus

Cause

Genetically speaking, Nezelof syndrome is autosomal recessive. the condition is thought to be a variation of severe combined immunodeficiency(SCID) However, the precise cause of Nezelof syndrome remains uncertain.

Inheritance

It is inherited in an autosomal recessive or X-linked recessive maaner.

Symptoms and signs

This condition causes severe infections. it is characterized by elevated immunoglobulins that function poorly. Other symptoms are:

• Bronchiectasis
• Hepatosplenomegaly
• Pyoderma
• Emphysema
• Diarrhea

Diagnosis

The diagnosis of Nezelof syndrome will indicate a deficiency of T-cells, additionally in ascertaining the condition the following is done:

• Blood test(B-cell will be normal)
• X-ray of thymus(atrophy present)

Differential diagnosis The differential diagnosis for this condition consists of acquired immune deficiency syndrome and severe combined immunodeficiency syndrome

Treatment

Bone marrow for transplant

• Bone marrow for transplant
• In terms of treatment for individuals with Nezelof syndrome, which was first characterized in 1964, includes the following(how effective bone marrow transplant is uncertain) :
• Antimicrobial therapy
• IV immunoglobulin
• Bone marrow transplantation
• Thymus transplantation
• Thymus factors

NIH genetic and rare disease info

• NIH info on Immune defect due to absence of thymus

Immune defect due to absence of thymus is a rare disease.