A 1-year-old boy is brought to the clinic to establish care after his family's recent move to the area. The patient was born at full term and has been growing and developing normally. Each day, he eats meat and pasta and drinks 300 mL (10 oz) of whole milk; however, he does not eat fruit and vegetables. The patient takes no daily medications or vitamins. Weight and height are at the 50th percentile. Conjunctivae and mucous membranes are pale. Cardiac examination reveals no murmurs. Pulmonary examination is normal. The abdomen is soft, and no hepatosplenomegaly is noted. Complete blood count results are as follows: Which of the following is the most likely cause of this patient's anemia?

Question

A 1-year-old boy is brought to the clinic to establish care after his family's recent move to the area.  The patient was born at full term and has been growing and developing normally.  Each day, he eats meat and pasta and drinks 300 mL (10 oz) of whole milk; however, he does not eat fruit and vegetables.  The patient takes no daily medications or vitamins.  Weight and height are at the 50th percentile.  Conjunctivae and mucous membranes are pale.  Cardiac examination reveals no murmurs.  Pulmonary examination is normal.  The abdomen is soft, and no hepatosplenomegaly is noted.  Complete blood count results are as follows:  Which of the following is the most likely cause of this patient's anemia?

Quizplus · Accepted Answer

11ec25c8_d6ae_32f2_bc81_79dbf3069b3a_MD0003_00 The most common causes of microcytic anemia in children are iron deficiency and thalassemia. Thalassemia is caused by impaired production of alpha- or beta-globin chains of hemoglobin. Clinical manifestations range from minor to severe, depending on the number of globin chains affected. Alpha- and beta-thalassemia minor (also known as thalassemia trait) are often asymptomatic and found incidentally on laboratory testing. Patients with thalassemia minor are often diagnosed by universal screening for anemia around age 1. Both types of thalassemia minor are characterized by abnormally small red blood cells (RBCs), reflected by a low mean corpuscular volume (MCV). A normal red cell distribution width (RDW) and normal-to-elevated total RBCs typically result in a Mentzer index (MCV/RBC) <13. Reticulocyte count may be slightly elevated due to a compensatory bone marrow response to anemia. Iron studies are typically performed to exclude iron deficiency anemia. Increased RBC turnover in thalassemia minor may result in slightly increased serum iron and ferritin levels. In addition, a peripheral smear of thalassemia shows target and teardrop cells. thalassemia (Choice A) Anemia of chronic disease is typically normocytic and normochromic but can be mildly microcytic; reticulocyte count is low due to decreased erythrocyte production. Anemia of chronic disease is unlikely in this child with no chronic medical problems. (Choice B) Folate deficiency presents as a macrocytic anemia (MCV >100 µm³) and occurs in individuals with poor dietary intake of vegetables or with increased requirements due to chronic hemolysis. macrocytic anemia (Choice C) Hereditary spherocytosis is caused by RBC membrane instability and typically presents with anemia, jaundice, and splenomegaly. Laboratory results demonstrate reticulocytosis, an elevated mean corpuscular hemoglobin concentration, a normal or slightly low MCV, a normal-to-elevated RDW, and spherocytosis. spherocytosis (Choice D) Iron deficiency anemia is the most common cause of microcytic anemia in children and is often caused by excessive cow's milk intake (>700 mL [24 oz] daily). Distinguishing laboratory findings include an increased RDW, a Mentzer index >13 (due to a decline in RBC count), and a low reticulocyte count. Educational objective: Thalassemia minor typically presents with microcytic anemia and a normal red cell distribution width. An elevated reticulocyte count reflects a compensatory bone marrow response to the anemia. References: Thalassaemia. (http://www.ncbi.nlm.nih.gov/pubmed/28774421)

A 1-Year-Old Boy Is Brought to the Clinic to Establish