A 3-month-old infant is seen for excessive sweating and fatigue during feeding. Examination reveals hepatomegaly and a pansystolic murmur at the lower left sternal border. CXR shows cardiomegaly and pulmonary congestion. What is the most probable diagnosis?

• Tetralogy of Fallot

• Ventricular Septal Defect

• Transposition of the Great Arteries

• Total Anomalous Pulmonary Venous Return

Answer explanation

The infant's symptoms of excessive sweating, fatigue, hepatomegaly, and the pansystolic murmur suggest heart failure due to a left-to-right shunt. A Ventricular Septal Defect (VSD) is the most common cause, leading to cardiomegaly and pulmonary congestion.

A 6-year-old child is found to have a cardiac murmur during a school screening. She is otherwise asymptomatic. Which of the following tests will best establish her cardiac diagnosis?

• Echocardiogram

• Chest X-ray

• Electrocardiogram

• Cardiac CT scan

Answer explanation

An echocardiogram is the best test to evaluate cardiac structure and function, making it ideal for diagnosing conditions related to a murmur in an asymptomatic child. Other tests like X-ray or ECG are less specific.

An 8-year-old child with an atrial septal defect has increased blood flow from the left atrium to the right atrium. Which option best classifies this congenital heart defect?

• Cyanotic heart defect with right-to-left shunt

• Acyanotic defect due to vascular narrowing

• Acyanotic defect with abnormal chamber communication

• Cyanotic defect with mixed blood flow

Answer explanation

An atrial septal defect allows increased blood flow from the left atrium to the right atrium, leading to abnormal chamber communication. This is classified as an acyanotic defect since it does not cause cyanosis.

A newborn has severe central cyanosis and is diagnosed with transposition of the great arteries. Prostaglandin E1 infusion is started. Why is PGE1 infusion important in this condition?

• To promote ductal closure

• To prepare for corrective surgery

• To relieve pulmonary hypertension

• To keep the ductus arteriosus open for blood mixing

Answer explanation

PGE1 infusion is crucial in transposition of the great arteries as it keeps the ductus arteriosus open, allowing for mixing of oxygenated and deoxygenated blood, which is vital for improving oxygenation in the newborn.

A 4-year-old child presents with hoarseness, inspiratory stridor, and a barking cough. Symptoms are worse at night and improve during the day. What is the recommended initial treatment?

• Oxygen therapy

• Inhaled bronchodilators

• Oral antibiotics

• Nebulized adrenaline with dexamethasone

Answer explanation

The child's symptoms suggest croup, characterized by stridor and a barking cough. Nebulized adrenaline provides rapid relief of airway swelling, while dexamethasone reduces inflammation, making this the recommended initial treatment.

A 10-month-old infant has difficulty feeding, cough, wheezing, and oxygen saturation of 88% on room air. Exam shows chest wall retractions and diffuse wheezes. Which diagnosis is most likely?

• Croup

• Childhood asthma

• Community-acquired pneumonia

• Bronchiolitis

Answer explanation

The infant's symptoms of cough, wheezing, and low oxygen saturation, along with chest wall retractions, are characteristic of bronchiolitis, commonly caused by viral infections in infants. Croup and asthma present differently.

A 9-year-old child presents with puffy eyelids and cola-colored urine. Blood pressure is elevated. Urine shows RBC casts. Which previous condition is most likely related to this presentation?

• Allergic rhinitis

• Skin infection

• Family history of nephritis

• Rheumatoid arthritis

Answer explanation

The child's symptoms suggest post-streptococcal glomerulonephritis, often following a skin infection like impetigo. The puffy eyelids, cola-colored urine, and RBC casts indicate kidney involvement related to this prior infection.

A 2-year-old child has a high fever, productive cough, and tachypnea. Exam reveals localized crepitations over the right lung. Which test is most useful in confirming pneumonia?

• Chest CT

• Chest X-ray

• Blood culture

• Arterial blood gas analysis

Answer explanation

A Chest X-ray is the most useful test to confirm pneumonia, as it can show lung infiltrates and help differentiate pneumonia from other conditions. Other tests like blood cultures and CT scans are less specific for this diagnosis.

A 13-year-old girl has facial swelling, hematuria, and joint pain. She also has a malar rash and hypertension. What is the most likely diagnosis?

• Lupus nephritis

• IgA nephropathy

• Acute post-streptococcal glomerulonephritis

• Nephrotic syndrome

Answer explanation

The girl's symptoms, including facial swelling, hematuria, joint pain, malar rash, and hypertension, are characteristic of lupus nephritis, a complication of systemic lupus erythematosus, making it the most likely diagnosis.

A child with confirmed nephrotic syndrome does not respond to steroid therapy after 6 weeks of treatment. What is the next appropriate action?

• Stop prednisolone immediately

• Add extra dietary salt

• Refer for renal biopsy

• Repeat urinalysis only

Answer explanation

In nephrotic syndrome, lack of response to steroids after 6 weeks suggests steroid-resistant disease. A renal biopsy is necessary to determine the underlying cause and guide further treatment.