Chapter 5, Problem 14Q

Summary Introduction

Case summary:

A patient, age 5 months reported with pneumocytosis which upon further investigation diagnosed as an immunodeficiency disorder called the Bare Lymphocyte Syndrome, Type II (BLSII).

Characters in the case:

Christina Kitchenman, the patient under evaluation.

Adequate information:

Initially patient reported with high fever and severe non-productive cough due to pneumocytosis (a fungal infection). Investigations were carried out that showed low CD4 T-cell count and slightly higher B-cell count when compared to normal reference levels. Further T-lymphocyte functionality tests and other tests revealed hypogammaglobulinemia. This is a state of deficiency of Class II MHC isotypes on WBCs without any deficiency of Class I MHC isotypes. As a treatment, she was given pentamidine and a successful bone marrow transplant.

To Determine:

The genetic defect in support of the diagnosis of Bare Lymphocyte Syndrome, Type II (BLSII).