MCQs In Pediatric Infectious Diseases -Part IV

A 10-year-old girl has had a rash for 4 days without other symptoms. She is taking no

medications. Physical examination reveals erythematous cheeks (Item Q1A) and a lacy,

reticulated erythema involving the extremities .

Of the following, the MOST likely diagnosis is

A. erythema infectiosum

B. phototoxic reaction

C. polymorphous light eruption

D. scarlet fever

E. systemic lupus erythematosus

MCQs In Pediatric Nephrology -Part IV

Q 1:

An 18-month-old girl is brought to the hospital with a history of 6 days of bloody diarrhea. She has been drinking well but has not been wetting her diaper. She has been irritable. On physical examination, she has periorbital edema. She appears pale and is tachycardic. Her CBC shows a hemoglobin of 6 g/dL and a

platelet count of 100,000/mm3. Her blood urea nitrogen (BUN) is 50 mg/dL and creatinine is 5.5 mg/dL. Her urinalysis shows gross hematuria. Which of the following is the most likely causative organism for her clinical problem?

(A) E. coli 0157:H7

(B) group A Streptococci

(C) group B Streptococci (GBS)

(D) S. aureus

(E) the cause of this illness is not known

MCQs In Neonatology - Part IV

Q 1:

A5-week-old bottle-fed boy presents with persistent and worsening projectile vomiting, poor weight gain, and hypochloremic metabolic alkalosis. Of the following diagnostic modalities, which would most likely reveal the diagnosis?

(A) ultrasound of abdomen

(B) barium enema

(C) evaluation of stool for ova and parasites

(D) testing well water for presence of nitrites

(E) serum thyroxine

Answer:

(A)

The case presented is classic of pyloric stenosis. This results from hypertrophy and hyperplasia of smooth muscle in the stomach, causing a narrowed, even, obstructed outlet.

Persistent projectile vomiting causes ongoing losses of calories and electrolytes, resulting in growth failure and hypochloremic metabolic alkalosis. Hyponatremia and hypokalemia may also be associated. Often, the diagnosis can be made by physical examination alone. However, if an olive-shaped mass is not palpated, an
abdominal ultrasound may confirm the diagnosis.

MCQs In Neonatal Hematology

Q 1:

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?

(A) child abuse

(B) vitamin K deficiency

(C) breast milk allergy

(D) sepsis

(E) liver disease

Answer:

(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.

MCQs In Pediatric Hematology

Q 1 -2 : The 2 questions are related

Q1:

A15-month-old African American male, who is otherwise healthy, is found to have a hemoglobin 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 30–40 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?

(A) sickle cell anemia

(B) thalassemia major

(C) lead poisoning

(D) iron-deficiency anemia

(E) anemia of chronic disease

Q 2:

The most effective next step in management would be to obtain which of the following?

(A) iron studies—serum iron, total iron binding capacity, ferritin

(B) reticulocyte count

(C) hemoglobin electrophoresis

(D) a repeat hemoglobin in 1 month after treatment with folic acid

(E) a repeat hemoglobin in 1 month after treatment with iron

Answer :

Q 1:

(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.

Q 2:

 (E)

If iron deficiency is strongly suspected, it is reasonable to treat empirically with 3–6 mg/kg/day of elemental iron. An increase in hemoglobin of 1 g/dL within 2–4 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

 A reticulocyte 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