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

MCQs Pediatric Otolaryngology

Q1:

Otitis media occurring during the first 4  weeks of life deserves special consideration, because the bacteria responsible for infections during this time may be different from those that affect older infants and children. Which of the following organisms is the most likely to cause otitis media in these infants?

(A) Chlamydia trachomatis

(B) E. coli

(C) Neisseria gonorrhoeae

(D) Treponema pallidum

(E) Toxoplasma gondii

Answer:

(B)

C. trachomatis is considered an unusual cause of otitis media at any age. N. gonorrhoeae causes conjunctivitis in the newborn. Syphilis and toxoplasmosis cause congenital infections. E. coli is one of the neonatal pathogens that also causes otitis media in neonates. The symptoms of otitis media in newborns are often similar to those of sepsis; they are subtle and nonspecific and may include poor feeding, lethargy,
vomiting, or diarrhea. Once the diagnosis is established, the initial therapy should be similar to that for neonatal sepsis, such as parenteral ampicillin and cefotaxime. Under ideal circumstances, the results of cultures obtained by tympanocentesis may then allow further treatment with a more specific antibiotic of low
toxicity. Older infants may respond well to oral therapy but require frequent observation.

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Q 2:

A 6-month-old infant is diagnosed with her first episode of otitis media. She does not have any allergies to medications. Which of the following medications would be the recommended initial therapy for this infant?

(A) amoxicillin
(B) amoxicillin-clavulanic acid
(C) cephalexin
(D) ceftriaxone
(E) erythromycin

Answer

(A) H. influenzae, S. pneumoniae, and Moraxella catarrhalis are the most common bacterial pathogens in otitis media of children. Amoxicillin is still the initial drug to use in uncomplicated otitis media because of its good coverage, except for beta-lactamase-positive organisms, and its excellent safety profile. The other drugs (except for erythromycin) are acceptable second-line medications.


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Q 3:

A 4-year-old previously healthy but unimmunized boy presents with sudden onset of high fever, inspiratory stridor, and refusal to drink. Of the following causes of inspiratory stridor, which best fits this clinical scenario?

(A) epiglottitis
(B) vascular ring
(C) croup
(D) foreign body aspiration
(E) laryngeal tumor


Answer:

(A)

Croup and epiglottitis have similar presentations but need to be distinguished immediately. Croup usually results from a viral infection of the larynx and epiglottitis from a bacterial (H. influenzae type B) infection of the epiglottis. Children with epiglottitis tend to be toxic in appearance. Croup involves the airway,
and epiglottitis involves the airway and the digestive tract. Children with croup usually will swallow and drink. Children with epiglottitis most often will refuse to drink and may even drool as a result of their refusal to swallow saliva. Patients with foreign bodies in their upper airways do not typically have fever.
Patients with vascular rings and laryngeal tumors have more gradual onset of symptoms.


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Q 4:

A 10-year-old boy is brought in with a chief complaint of multiple colds. On further questioning, you elicit a history of chronic, clear nasal discharge with no seasonal variation. Other symptoms include sneezing, itching of the nose and eyes, as well as tearing and occasional eye redness. Some relief is obtained with
an over-the-counter cold medicine containing antihistamine and a decongestant. His history suggests which of the following?

(A) nasal foreign body
(B) immunologic deficiency
(C) rhinitis medicamentosa
(D) chronic sinusitis
(E) allergic rhinitis

Anser


(E)

The symptoms are suggestive of perennial allergic rhinitis. Causative agents are usually those to which the child is exposed year round, such as house dust, mold spores, or pet danders.

Seasonal allergic rhinitis is attributable to sensitization to pollens of trees, grasses, and weeds. Nasal foreign bodies usually result in a foul smelling, unilateral purulent, and occasionally blood tinged, discharge. Recurrent
infections may rarely be attributable to immunologic deficiencies. Recurrent pneumonias are the most common complaint.

Rhinitis medicamentosa occurs secondary to excessive use of vasoconstrictor nose drops or sprays,
resulting in rebound nasal obstruction.

Sinusitis is suggested by a bilateral purulent nasal discharge, often accompanied by fever,
cough, headache, and sometimes sinus tenderness.

MSQs In bone diseases

Q1:

A 1-year-old Saudi infant is in for well-child care. He is primarily breast-fed. His parents do not give him much solid food because he has no teeth. He receives no medications or supplements. His parents are concerned about his bowed legs. On examination, you note some other bony abnormalities including frontal bossing, enlargement of the costochondral junctions, a protuberant sternum (pigeon chest), and severe bowing of the legs. You obtain x-rays to confirm your clinical diagnosis and also note a healing fracture of the

left femur. Which of the following is the most likely diagnosis?

(A) osteogenesis imperfecta

(B) scurvy

(C) congenital syphilis

(D) rickets

(E) chondrodystrophy

Answer

(D)

 Babies who are exclusively breast-fed for prolonged periods of time are at risk for developing rickets. Dark-skinned infants are at high risk, especially during winter months when they receive inadequate sunlight. Supplementation with vitamin D is recommended in children who are at high risk, as well as pregnant and lactating mothers. Clinical features include craniotabes, a thinning of the outer table of the skull.

This may also occur in osteogenesis imperfecta. Enlargement of the costochondral junctions (rachitic rosary) may be seen in rickets, scurvy, and chondrodystrophy. Other features may include delayed primary teeth, enamel defects, and caries. There may be thickening of the wrists and ankles; bending of the femur, tibia, and
fibula result in bowlegs or knock-knees.

Greenstick fractures of long bones may occur without symptoms.

 Diagnosis is based on history of inadequate vitamin D intake and clinical features. Diagnosis may be confirmed by x-rays and chemistry; serum calcium is low or normal, serum phosphorus is low, serum
alkaline phosphatase is elevated, and serum 25-hydroxycholecalciferol is decreased. Breast milk contains adequate vitamin C as long as the mother is not deficient.