Showing posts with label pediatrics. Show all posts
Showing posts with label pediatrics. Show all posts

Saturday, August 11, 2018

Repeated USMLE Questions Step 2 CK- 261

A 9-month-old baby is brought in to the doctor as he has been having a persistent cough, poor weight gain, and has already had several bouts of pneumonitis. On taking the history from the mother, it is known that the baby has been having foul-smelling and very large stools for several months.

Which of the following diagnostic techniques will provide you with the correct diagnosis of this patient?

A- TB skin test

B- CT of the chest

C- Serum immunoglobulins

D- Sweat chloride test


Keeping the symptoms of the baby in mind, doctors will first suspect cystic fibrosis, which generally presents during infancy with poor growth and recurrent respiratory and/or intestinal diseases. The sweat chloride test is one of the most common diagnostic tests used to evaluate a patient if you suspect cystic fibrosis. Cystic fibrosis impacts the manner in which chloride moves in and out of cells. As sweat contains chloride in the form of sodium chloride, sweat chloride test is used as the standard method for diagnosing cystic fibrosis.

The correct answer is D

Saturday, January 20, 2018

Repeated USMLE Questions Step 2 CK- 257

A 16-month old boy is brought to the clinic by his mother who is concerned that her boy turns blue and becomes short of breath several times during last three months. During these episodes, her becomes irritable and stays in squatting position until he relieves. Cardiac examination reveals systolic ejection murmur over the upper right sternal border. X-ray shows boot-shaped heart.

What is the most likely diagnosis?

A- Tetralogy of Fallot

B- Total anomalous pulmonary venous return

C- Transposition of the great arteries

D- Tricuspid atresia

E- Truncus arteriosus


This is a case of cyanotic heart disease. As we may all know, congenital heart diseases are classified into cyanotic and non-cyanotic heart diseases. Also, cyanotic heart diseases are further classified into early and late cyanotic depending upon if they are diagnosed early in the neonatal period or later. Total anomalous pulmonary venous connection, transportation of the great vessels, tricuspid atresia and truncus arteriosus are examples of early cyanotic congenital heart diseases which show right after birth. Tetralogy of Fallot is usually revealed later on or after the neonatal period due the development of right-to-left shunt through the ventricular septal defect.

Fallot of Tetralogy is characterized by ventricular septal defect, pulmonary stenosis, right ventricular hypertrophy and overriding aorta. Sometimes, as in this case, it appears later after the neonatal period and it causes "tet spells" which are episodes of cyanosis, dyspnea, irritability and loss of consciousness. Some kids develop natural relief by squatting which increases venous return to the heart leading to relief of these episodes.

The correct answer is A