1. The patient shown below is a premature newborn. The most likely diagnosis is:

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  a. Transient tachypnea of the newborn  b. Congenital lobar emphysema  c. Hyaline membrane disease  d. Cystic adenomatoid malformation  e. Meconium aspiration syndrome

Correct Answer: Hyaline membrane diseaseYour Answer:Transient tachypnea of the newborn

ExplanationThere is a diffuse and somewhat uniform, hazy, “ground-glass” appearance to the lungs. The lungs are not overaerated. Hyaline membrane disease, which is also called Respiratory Distress Syndrome of the Newborn (RDS), is caused by inadequate surfactant production which leads to atelectasis, intrapulmonary shunting, reduced lung compliance and hyaline membrane formation. Premature infants, infants of diabetic mothers and infants delivered by Cesarean section are predisposed.

2. The patient is a 3 month old. What is the most likely diagnosis?

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  a. Transient tachypnea of the newborn  b. Congenital lobar emphysema  c. Hyaline membrane disease  d. Cystic adenomatoid malformation  e. Meconium aspiration syndrome

Correct Answer: Cystic adenomatoid malformationYour Answer:Congenital lobar emphysema

ExplanationThere is overaeration of the left lung with a shift of the heart and mediastinal structures to the right. Of importance is the presence of the stomach bubble in its usual position beneath the left hemidiaphragm. Cystic adenomatoid malformation is a unilateral expansile mass of disorganized pulmonary tissue which typically communicates with the bronchial tree and has a normal vascular supply. The opposite lung can be hypoplastic. In certain types, it can be associated with other fetal anomalies of the heart, kidneys or small bowel.

3. The patient is a post-mature newborn. What is the most likely diagnosis?

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  a. Transient tachypnea of the newborn  b. Congenital lobar emphysema  c. Hyaline membrane disease  d. Cystic adenomatoid malformation  e. Meconium aspiration syndrome

Correct Answer:Meconium aspiration syndromeYour Answer:Hyaline membrane disease

ExplanationThere are thick, rope-like densities throughout both lungs. The lungs are overaerated. Meconium aspiration typically occurs in postmature infants who have some fetal distress. Aspirated meconium can produce chemical pneumonitis and atelectasis from bronchial obstruction. These infants are frequently meconium-stained. Despite a 25% incidence of spontaneous pneumothorax, most clear with 48 hours.

4. The patient shown below most likely has:

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  a. Transient tachypnea of the newborn  b. Congenital lobar emphysema  c. Hyaline membrane disease  d. Cystic adenomatoid malformation  e. Meconium aspiration syndrome

Correct Answer: Congenital lobar emphysemaYour Answer:Cystic adenomatoid malformation

ExplanationThere is overaeration of the left upper lobe and shift of the heart and mediastinal structures toward the right. These are signs of an overexpanded lobe. Congenital lobar emphysema may appear after birth as a mass-like density containing fluid which then becomes more lucent as it fills with air over the first two weeks of life. It most often involves the left upper lobe and may produce respiratory distress and cyanosis. The treatment is surgical resection.

5. The patient is a premature infant with respiratory distress. A film done the next day is normal. What is the most likely diagnosis?

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  a. Transient tachypnea of the newborn  b. Congenital lobar emphysema  c. Hyaline membrane disease  d. Cystic adenomatoid malformation  e. Meconium aspiration syndrome

Correct Answer: Transient tachypnea of the newbornYour Answer:Meconium aspiration syndrome

ExplanationThere is fluid in the minor fissure and there is a right pleural effusion present. These are signs of excess fluid in the lungs. The history given is that this is a premature infant whose chest x-ray clears rapidly. The findings are those of Transient Tachypnea of the Newborn (TTN). TTN occurs in babies born by C-section and who are premature. It is thought to be due in part to the lack of thoracic compression that occurs with vaginal delivery. The respiratory rate is typically elevated. It clears rapidly, usually within 1-4 days.