TABLE I.

Differential diagnosis of hypogammaglobulinemia

Drug induced

Antimalarial agents

Captopril

Carbamazepine

Glucocorticoids

Fenclofenac

Gold salts

Penicillamine

Phenytoin

Sulfasalazine

Anti-CD20 mAbs (rituximab)

Single gene and other defects

Ataxia telangiectasia

Autosomal-recessive forms of SCID and other forms of combined     immunodeficiency

Hyper-IgM syndromes

Transcobalamin II deficiency and hypogammaglobulinemia

X-linked agammaglobulinemia

X-linked lymphoproliferative disorder (EBV-associated)

X-linked SCID

Some metabolic disorders

Chromosomal anomalies

Chromosome 18q-syndrome

Monosomy 22

Trisomy 8

Trisomy 21

Infectious diseases

HIV

Congenital infection with rubella virus

Congenital infection with cytomegalovirus

Congenital infection with Toxoplasma gondii

EBV

Malignancy

Chronic lymphocytic leukemia

Immunodeficiency with thymoma

Non-Hodgkin lymphoma

Monoclonal gammopathy (mutiple myeloma, Waldenstrom     macroglobulinemia)

Other systemic disorders

Immunodeficiency caused by excessive loss of immunoglobulins     (nephrosis, severe burns, lymphangiectasia, protein-losing     enteropathy)

SCID, Severe combined immunodeficiency