Question

Case study

8-year old girl with recurrent infections caused by Streptococcus pyogenes and Hemophilus influenza was admitted to the hospital following a 5-day sinus infection. Her mother noted that she had developed a productive cough and high fever. Her white blood cell count was 3200/ul (normal count 5000-9000/ul). 25% percent of her white cells were neutrophils (very low), 40% were lymphocytes (normal), and 29% were monocytes (elevated, normal 2 to 8%). A serum test revealed that her IgG level was 35 mg/dl (normal 600-1500 mg/dl), IgA was undetectable (normal 150-225 mg/dl) and her IgM level was 210 mg/dl (normal 75-150 mg/dl). A flow cytometric analysis of her peripheral blood cells revealed that all of her B cells were IgM⁺, IgD⁺.

1. Explain the reason(s) for an increase in monocytes and abnormal levels of immunoglobulins (IgG, IgA, and IgM).

Answer 1

The history of recurrent infections by Streptococcus pyogenes and hemophilus influenza suggests primary immunodeficiency disease.The child developed productive cough and fever ;indicatimg infection but her white blood cell count is below normal.There is neutropenia and monocytosis.Monocytosis occurs in response to the infection in the deficiency of neutrophils.Her IgG and IgA levels were low but IgM level is increased.This is due to humoral immunodeficiency and it is most probably immunodeficiency with hyper-IgM.In this disease ; IgM levels are elevated while level of other immunoglobulins are low.