A15-month-old African American male, who is otherwise healthy, is found to have an emoglobin level of 8 g/dL on routine screening. The mean corpuscular volume (MCV) is decreased. His lead screen is within normal limits. You obtain a diet history, which reveals that he drinks about 3040 oz of whole cow's milk a day. He eats no meat and some fruits and vegetables.Which of the following is the most likely cause?
Answer(s): D
Iron deficiency is the most common cause of microcytic anemia. In children it is often related to excessive consumption of cow's milk, which is low in iron content, and inadequate consumption of iron-rich foods.Allergy to cow's milk may also cause occult GI blood losses. In thalassemia major, there is usually physical evidence of chronic anemia with signs of bone marrow expansion (frontal bossing) and severe anemia often requiring transfusions. Lead poisoning may cause microcytic anemias; it may also be associated with iron-deficiency anemia, which enhances lead absorption and, therefore, should always be excluded.Anemia of chronic disease (renal disease) may be microcytic or normocytic and should be excluded by history and examination.
A15-month-old African American male, who is otherwise healthy, is found to have an emoglobin level of 8 g/dL on routine screening. The mean corpuscular volume (MCV) is decreased. His lead screen is within normal limits. You obtain a diet history, which reveals that he drinks about 3040 oz of whole cow's milk a day. He eats no meat and some fruits and vegetables.The most effective next step in management would be to obtain which of the following?
Answer(s): E
If iron deficiency is strongly suspected, it is reasonable to treat empirically with 36 mg/kg/day of elemental iron. An increase in hemoglobin of 1 g/dL within 24 weeks confirms the diagnosis. If laboratory confirmation is necessary because the child is at low risk for iron deficiency, confirmatory iron studies may be obtained.The serum iron is low, the total iron binding capacity high, and the ferritin is low. Areticulocyte count is helpful in hemolytic anemias where it is elevated. Bone marrow aspirate in iron deficiency is necessary if bone marrow infiltration is suspected (leukemia), but is overinvasive in this situation. Hemoglobin electrophoresis may be done if thalassemia or sickle cell anemia is likely.
Aweek-old infant presents blood in his stools. He was born at home, with the father assisting in the delivery; no physician or midwife was present. He has been breast-fed and has been nursing well. On examination, you also note some blood in his nose. He is not jaundiced; a rectal examination and guaic test of the stool confirms that blood is present. His examination is otherwise normal. He is on no medications.Which of the following is the most likely diagnosis?
Answer(s): B
Neonates are routinely given intramuscular vitamin K at the time of birth. This is done to prevent the transient deficiency of vitamin- K-dependent factors, which occurs because of absence of bacterial intestinal flora which synthesize vitamin K. Hemorrhagic disease in the newborn because of vitamin K deficiency may result in GI, nasal, subgaleal, and intracranial bleeding, or bleeding after circumcision. The prothrombin time (PT), partial thromboplastin time (PTT), and bleeding time are prolonged. These all correct after administration of vitamin K. Child abuse should always be considered with unusual bleeding, but the history reveals the etiology in this case. Babies are more likely to be allergic to formula than breast milk; however, it occurs rarely and may present with bloody stools. It does not, however, cause epistaxis.Neonatal sepsis may result in disseminated intravascular coagulation and bleeding; the infant is usually ill appearing, with associated acidosis or shock. Liver disease may cause factor deficiencies and should be excluded if there is no response to vitamin K.
A 6-year-old Caucasian female has breast enlargement (Tanner stage II) and coarse curly pubic hair. She is not yet menstruating. She is otherwise healthy and has normal growth parameters. There are no signs of virilization and her abdominal examination reveals no masses. Examination of the vaginal area shows signs of estrogenization.Which of the following is the most likely preliminary working diagnosis?
Answer(s): A
Precocious puberty has been redefined for girls as the presence of either pubic hair or breast development before age 6 for African Americans and age 7 for Caucasians. Premature thelarche is the isolated development of breasts, with no other secondary sexual development. Premature pubarche is the isolated development of pubic or axillary hair (sexual hair). Precocious menarche is a rare form of incomplete precocious puberty with cyclic menstruation but no other secondary sexual characteristics.
A 6-year-old Caucasian female has breast enlargement (Tanner stage II) and coarse curly pubic hair. She is not yet menstruating. She is otherwise healthy and has normal growth parameters. There are no signs of virilization and her abdominal examination reveals no masses. Examination of the vaginal area shows signs of estrogenization.On laboratory evaluation, you find elevated levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and pubertal levels of estradiol. The bone age is advanced beyond the height and chronologic age.The most likely cause is which of the following?
The laboratory and radiologic studies indicate a form of central precocious puberty. It is most likely to be idiopathic; however, imaging of the head as well as a careful neurologic and visual examination is recommended to exclude a CNS lesion (tumor, trauma, hamartoma, and so forth). Estradiol secreting ovarian tumors and functional ovarian cysts may cause peripheral precocious puberty; however, the levels of FSH and LH are prepubertal. Congenital adrenal hyperplasia results in signs of virilization; these include excessive hirsutism, deepening voice, acne, clitoromegaly, and muscle development.
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