A 19-year-old woman is brought to the emergency department after a motor vehicle collision. The patient's medical history includes celiac disease and 3 episodes of pneumonia. Her blood pressure is 80/45 mm Hg and pulse is 130/min. Physical examination reveals pallor, and ultrasound shows a splenic laceration. She receives a blood transfusion with O-negative packed red blood cells. During transfusion, the patient develops facial swelling, generalized hives, and shortness of breath. Which of the following is the most likely diagnosis in this patient?

Question

A 19-year-old woman is brought to the emergency department after a motor vehicle collision.  The patient's medical history includes celiac disease and 3 episodes of pneumonia.  Her blood pressure is 80/45 mm Hg and pulse is 130/min.  Physical examination reveals pallor, and ultrasound shows a splenic laceration.  She receives a blood transfusion with O-negative packed red blood cells.  During transfusion, the patient develops facial swelling, generalized hives, and shortness of breath.  Which of the following is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

11ec160b_37dd_64bf_9249_c36beb0d8ed6_MD0001_00 This patient has a history of recurrent pneumonia, a diagnosis of celiac disease, and an anaphylactic reaction during blood transfusion. These findings are highly suggestive of selective IgA deficiency, the most common primary immunodeficiency. Although most patients with IgA deficiency are asymptomatic, some may have recurrent sinopulmonary (eg, sinusitis, pneumonia) and gastrointestinal infections (eg, Giardia) due to absence of secretory IgA. Concomitant autoimmune disorders (eg, celiac disease) are also common. Patients with severe IgA deficiency can form IgE antibodies directed against IgA (anti-IgA antibodies). Serum IgA levels are low or undetectable due to failure of B cells to differentiate into IgA-secreting plasma cells; serum IgG and IgM levels are normal. When transfused with blood products (eg, red blood cells, platelets, fresh frozen plasma) containing small amounts of IgA, these patients can develop potentially fatal anaphylaxis. Therefore, patients with severe IgA deficiency should wear medical alert bracelets and receive blood products that are washed of residual plasma or from an IgA-deficient donor. (Choice A) Acute hemolytic reactions occur when a patient's preexisting IgM or IgG antibody cross-reacts with antigens (eg, A, B, Rh, Kell) in transfused blood. Reactions range from fever and chills to severe hemolysis and circulatory collapse. However, anaphylaxis is IgE-mediated and does not result from ABO incompatibility. (Choice B) C1 inhibitor deficiency causes hereditary angioedema that can be triggered by transfusions. Affected patients have angioedema but do not have urticaria or wheezing, both of which are present in this patient. (Choice C) Leukocyte adhesion deficiency results in poor leukocyte adherence and transmigration through the vasculature. Affected patients present with recurrent skin and mucosal infections but are not at an increased risk for anaphylaxis during transfusion. (Choice E) Severe combined immune deficiency results from failure of T cell development and leads to a severe defect of cell-mediated and humoral immunity. This disease causes severe bacterial, viral, and fungal infections beginning in infancy. Educational objective: Selective IgA deficiency is the most common primary immune deficiency and can present with recurrent sinopulmonary and gastrointestinal infections as well as autoimmune disease. Patients with severe IgA deficiency can have anaphylaxis during transfusion of blood products that contain small amounts of IgA. __________ References: Selective IgA deficiency. (http://www.ncbi.nlm.nih.gov/pubmed/20101521)

A 19-Year-Old Woman Is Brought to the Emergency Department After