Abstract
Ataxia telangiectasia (AT) is a rare multisystem, neurodegenerative genetic disorder.
Due to its wide clinical heterogeneity, it often leads physicians to an incorrect
or missed diagnosis, and insight into this rare disease is important. Here is a case
report of two cousins from the same family who showed salient characteristic features
of AT along with the incidental finding of co-inheritance of hemoglobin E trait. Though
both of them were from the same family, they showed differences in the type of humoral
immune deficiencies, laboratory findings, and their susceptibility to develop different
types of malignancies. One of them developed T cell acute lymphoblastic leukemia,
isolated immunoglobulin A deficiency, and normal serum carcinoembryonic antigen (CEA)
and carbohydrate antigen 19.9 (CA 19.9) levels. He expired at the age of nine years.
The other, though a year older, has still got normal blood counts, normal immunoglobulin
levels, and elevated serum CEA and CA 19.9 levels. Thus, insight into this disease
is very important as AT patients require protection from unnecessary exposure to ionizing
radiation to prevent malignancies. Diagnosis of AT allows appropriate genetic counseling
for the family.
Keywords
Ataxia telangiectasia - hemoglobin E - T cell acute lymphoblastic leukemia - humoral
immunodeficiency
