Congenital defects — MCQs

A 15-year-old boy is brought to the physician because of recurrent respiratory infections that cause him to miss several weeks of school each year. He also has bulky, foul-smelling stools that are difficult to flush. He has a good appetite and eats a variety of foods. His height and weight are below the 10th percentile. Physical examination shows multiple nasal polyps. There is mild wheezing over the lower lung fields. Further evaluation is most likely to show which of the following?

A 1-day-old infant in the general care nursery, born at full term by uncomplicated cesarean section delivery, is noted to have a murmur, but otherwise appears well. On examination, respiratory rate is 40/min and pulse oximetry is 96%. Precordium is normoactive. With auscultation, S1 is normal, S2 is single, and a 2/6 systolic ejection murmur is heard at the left upper sternal border. Echocardiography shows infundibular pulmonary stenosis, overriding aorta, ventricular septal defect and concentric right ventricular hypertrophy. Which of the following correlate with the presence or absence of cyanosis in this baby?

A 1-month-old girl presents to her pediatrician with her mother. The patient was born at 38 weeks gestation via Caesarian section for cervical incompetence. The patient’s mother has no complaints, although she notes that the child had a runny nose and cough for a few days last week. The patient’s mother endorses decreased appetite during the aforementioned illness which has now returned to baseline. The patient’s family history is significant for an older brother with glucose-6-phosphate dehydrogenase (G6PD) deficiency and a maternal uncle with cirrhosis secondary to chronic hepatitis B. On physical exam, the patient has scleral icterus and dark urine staining her diaper. Laboratory testing reveals the following: Serum: Na+: 137 mEq/L Cl-: 102 mEq/L K+: 4.2 mEq/L HCO3-: 24 mEq/L Urea nitrogen: 12 mg/dL Glucose: 96 mg/dL Creatinine: 0.36 mg/dL Alkaline phosphatase: 146 U/L Aspartate aminotransferase (AST): 86 U/L Alanine aminotransferase (ALT): 76 U/L Total bilirubin: 4.6 mg/dL Direct bilirubin: 3.8 mg/dL Which of the following is the most likely diagnosis?

An 18-month-old boy is brought to the physician for a well-child examination. His mother is concerned because he is unable to walk on his own. He has been increasingly irritable over the past month, has been feeding poorly, and has had multiple episodes of vomiting. His immunizations are up-to-date. He is at the 50th percentile for height, 40th percentile for weight, and 98th percentile for head circumference. He appears lethargic. His vital signs are within normal limits. Examination shows a bulging anterior fontanelle. The child is unable to stand without support and falls if he attempts to walk. Muscle tone is increased and deep tendon reflexes are 4+ in the lower extremities. Examination of the back is unremarkable. An MRI of the brain shows symmetrical enlargement of all four ventricles. Which of the following is the most appropriate treatment in this patient?

A newborn infant is resuscitated and transferred to the neonatal intensive care unit. The infant has notable limb deformities as well as low-set ears and a flattened nose. He was born at 34 weeks gestation to a healthy mother who received regular obstetric follow-up. Resuscitation was notable for difficulty maintaining oxygenation in the newborn. Despite appropriate interventions, the infant is still struggling to maintain adequate oxygenation. Which of the following is most likely the cause of this patient's symptoms?

A 6-month-old male presents with a painless, enlarged left scrotum. After examining the patient, you suspect this enlargement is secondary to serous fluid entering and accumulating in the scrotum through a patent processus vaginalis. Which of the following would be the most useful next step in confirming the diagnosis of this patient’s condition?

A 5-year-old boy is brought to his neurologist for continued treatment of muscle spasms. His past medical history is significant for a brain abnormality that was detected neonatally when it presented with an enlarged posterior fossa as well as a malformed cerebellar vermis. Since birth, he has had developmental delay, high muscle tone, difficulty with coordination, and speech delay. He has been treated with a number of therapies to relax his muscle tone such as baclofen. Which of the following conditions is associated with this patient's most likely condition?

A 2-month-old boy is brought to the emergency department by his mother because of an 8-hour history of difficulty feeding and decreased arousability. His mother says that the symptoms began after he rolled over and fell from the bed. His vital signs are within normal limits. Examination shows tense fontanelles. Fundoscopy shows bilateral optic disc swelling with dot-and-blot hemorrhages extending to the ora serrata. Which of the following is the most likely diagnosis?

A 4-year-old girl is brought to the pediatrician by her parents for a 1-year history of gradual loss of speech and motor skills. Pregnancy and delivery were uncomplicated, and development was normal until the age of 3 years. Her parents say she used to run and speak in short sentences but now is only able to walk slowly and cannot form sentences. She avoids eye contact and constantly rubs her hands together. There are no dysmorphic facial features. Neurologic examination shows marked cognitive and communicative delay. She has a broad-based gait and is unable to hold or pick up toys on her own. Which of the following mutations is the most likely underlying cause of this patient's condition?

A 4-year-old-female presents with a flattened, reddish 2 cm lump located at the base of the tongue. The patient's mother reports her having trouble swallowing, often leading to feeding difficulties. The mother also reports lethargy, constipation, dry skin, and hypothermia. Which of the following is the most appropriate management of this patient’s presentation?