Abstract
Background: Selective IgM deficiency (sIgMD), classified under primary
immunodeficiencies, is characterized by low serum IgM(<2SD for
age), normal IgG and IgA levels. The aim of this study was to define
immunologic and clinical features of sIgMD. Method: We assessed a
retrospective medical record of patients who fullfilled the criteria for
sIgMD in a Pediatric Immunology department. Results: There were 55
patients with sIgMD. Out of 55 patients, thirteen(23.6%) diagnosed with
a well-defined primary immunodeficiency (PID) during the follow-up.The
ratio of the sIgMD was %0.12 in the out-patient clinic of pediatric
immunology. Out of 33 patients, 8(23.5%) were asymtomatic during the
follow-up period. Fifteen(45.4%) patients presented with several type
of infections). Six patients (18%) had chromosomal anomaly, or syndrome
(trisomy 21, 22q11.2 deletion 1p deletion, CHARGE syndrome, and Cohen
Syndrome). Six (18%) had autoimmune/inflammatory diseases, such as
Behcet’s disease, immune thrombocytopenic purpura, Crohn disease,
Guillain Barre syndrome, and diabetes mellitus. Five(15%) had allergic
disorders. Three(9%) have developed malignancy. The diagnoses of
thirteen PID patients were combined immunodeficiency, common variable
immunodeficiency, autoimmune lymphoproliferative syndrome, chronic
granulomatous disease, adenosine deaminase deficiency, and congenital
neutropenia. Genetic disorders, autoimmune/inflammatory and allergic
diseases may accompany sIgMD. Approximately one third of the patients
were asymptomatic in our series. Malignancy risk is relatively
increased. We observed that an important ratio of patients with low IgM
(23.6%) got sooner the diagnosis of a specific PID in the follow-up
period. Conclusion: Thus, patients with sIgMD should be followed
regularly in immunology clinics.