41. Topic: Signs and Symptoms of Teething

Correct Answer: E. A fever of 39°C

Explanation: Teething in infants is commonly associated with mild symptoms: Option A (Rhinorrhea) Mild nasal congestion or a runny nose can sometimes be seen. Option B (Diarrhea) Some infants may experience loose stools due to increased saliva swallowing. Option C (Decrease in appetite) Infants may eat less due to gum discomfort. Option D (Irritability) Commonly seen as the baby experiences gum pain and discomfort. Option E (A fever of 39°C) is not typically attributed to teething. While a slight increase in body temperature can occur, high fever (39°C or above) usually indicates an infection or another illness and should be evaluated by a healthcare provider. Therefore, option E is correct because a high fever is not a typical symptom of teething and suggests another underlying condition.

42. Topic: Contraindications to Inducing Vomiting in Child Poisoning

Correct Answer: B. Rapidly increasing drowsiness

Explanation: Inducing vomiting in cases of child poisoning is generally contraindicated in the following scenarios: Option A (Ingestion of turpentine) Vomiting can cause aspiration and chemical pneumonitis. Option C (Ingesting a drain cleaner) Corrosive substances can cause additional damage to the oesophagus and mouth when vomited. Option D (Acetaminophen ingestion) Vomiting is not recommended as it does not improve outcomes and there are better treatments like activated charcoal or N-acetylcysteine. Option E (Ingestion by a child under 6 months of age) Infants have a higher risk of aspiration and other complications from induced vomiting. Option B (Rapidly increasing drowsiness) While drowsiness indicates CNS involvement and potential risk, it is not in itself a direct contraindication to inducing vomiting. In such cases, rapid medical assessment and treatment are critical, and other methods of decontamination or antidotal therapy might be prioritized. Therefore, option B is correct because rapidly increasing drowsiness, while serious, does not alone contraindicate inducing vomiting as strongly as the other listed scenarios.

43. Topic: Newborn Respiratory Distress

Correct Answer: B. The diaphragmatic hernia

Explanation: A diaphragmatic hernia is a condition where abdominal organs herniate into the chest cavity through a defect in the diaphragm. This can lead to severe respiratory distress immediately after birth due to compromised lung development and function. Option A (Respiratory distress syndrome) Typically associated with preterm infants and surfactant deficiency, not term infants with a multicystic mass. Option C (The tracheoesophageal fistula) Usually presents with feeding difficulties and aspiration, not a multicystic mass in the chest. Option D (Congenital lobar emphysema) Characterized by overinflation of a lung lobe, but not typically presenting as a multicystic mass with mediastinal displacement. Option E (The persistence of fetal circulation): Refers to conditions like persistent pulmonary hypertension of the newborn, which would present differently on a chest X-ray. The key features leading to the diagnosis of a diaphragmatic hernia are the severe respiratory failure, diminished breath sounds, flat abdomen, and a multicystic mass in the chest with mediastinal shift, all of which are consistent with abdominal organs in the thoracic cavity.

44. Topic: Differential Diagnosis of Persistent Hypoglycemia in Infants

Correct Answer: D. Asymmetric growth retardation

Explanation: Persistent hypoglycemia in infants with high serum insulin levels is suggestive of hyperinsulinism. Conditions associated with hyperinsulinism include Option A (Beckwith-Wiedemann syndrome) A genetic disorder that often presents with macroglossia, omphalocele, and neonatal hypoglycemia due to hyperinsulinism. Option B (Nesidoblastosis) Refers to an abnormal increase in the number of insulin-secreting cells in the pancreas, leading to hyperinsulinism and persistent hypoglycemia. Option C (Maternal diabetes) Infants of diabetic mothers may experience hyperinsulinemia and subsequent hypoglycemia post-birth due to the high maternal glucose levels during pregnancy. Option E (Pancreatic islet cell carcinoma): Though rare in infants, it can cause hyperinsulinism and persistent hypoglycemia. Asymmetric growth retardation (Option D) generally does not cause hyperinsulinism. This condition typically results from intrauterine growth restriction due to various factors, but it does not directly lead to high insulin levels. Therefore, it is the exception in this context.

45. Topic: Fluid Balance in Newborns

Correct Answer: C. Replacement of sodium, potassium, and chloride in physiological amounts is started at 24 hours of age in the presence of normal urine production

Explanation: Fluid balance in newborns is crucial due to significant changes in water compartments and diuresis. The key points regarding fluid balance include Option A (Sensible water loss): Sensible water loss includes measurable losses like urine and stool, but not lung and gastric fluid loss, which are considered insensible losses. Option B (Insensible water loss): Insensible water loss, such as loss through the skin and respiratory tract, is indeed increased by factors like phototherapy, radiant heaters, and elevated ambient temperatures. Option D (Water loss in premature babies): Premature infants do experience greater water loss during the first week of life due to a higher surface area-to-body weight ratio and an immature skin barrier. Replacement of electrolytes like sodium, potassium, and chloride (Option C) is typically started later, not necessarily at 24 hours of age, even if urine production is normal. The timing of electrolyte replacement depends on the infant’s overall clinical condition and lab results. This makes Option C the incorrect statement.

46. Topic: Marfan Syndrome

Correct Answer: A. Aortic dilatation and loose joints suggesting a connective tissue disorder

Explanation: Marfan syndrome is a connective tissue disorder characterized by: Option A (Aortic dilatation and loose joints): Marfan syndrome frequently presents with aortic dilatation and loose joints, reflecting the underlying connective tissue disorder. This can lead to complications such as aortic aneurysm or dissection. Option B (Excess length and width of bones): Marfan syndrome does involve excessive bone length, but it is not primarily a bone metabolism disorder. Instead, it is the result of abnormalities in connective tissue. Option C (Loose tendons and ligaments): While loose tendons and ligaments can be observed, this is due to connective tissue abnormalities, not muscle cell development disorders. Option D (Large size and excess subcutaneous tissue): Marfan syndrome does not typically present with excess subcutaneous tissue or large size due to growth factor disorders; rather, individuals often appear tall and thin. Therefore, aortic dilatation and loose joints are key indicators of Marfan syndrome, correctly suggesting a connective tissue disorder.

47. Topic: Down Syndrome

Correct Answer: C. Gastrointestinal abnormalities occur with increased frequency

Explanation: Down syndrome, or trisomy 21, is characterized by several well-documented features and associated conditions: Option A (Most frequent chromosomal anomaly): Down syndrome is indeed the most common chromosomal disorder. Option B (One of the parents causes this anomaly): Down syndrome typically results from a random error in cell division, not directly caused by parental actions or conditions. Option D (Severely or profoundly retarded): While intellectual disability is common in Down syndrome, the severity varies, and many individuals have mild to moderate intellectual disability. Option E (Probability of recurrence): The recurrence risk of Down syndrome in subsequent pregnancies is approximately 1% to 2%. Gastrointestinal abnormalities (Option C), such as duodenal atresia or Hirschsprung disease, occur with increased frequency in Down syndrome, but it is not the intruder statement. Instead, “There is nothing but one of the parents that causes this anomaly” (Option B) is misleading as Down syndrome is generally not caused by the parents but rather by nondisjunction during cell division.

48. Topic: Allergic Rhinitis

Correct Answer: C. Dental malocclusion

Explanation: Allergic rhinitis is commonly associated with a variety of symptoms and signs: Option A (Dark shadows under the eyes): Known as “allergic shiners,” these are common in allergic rhinitis due to venous congestion. Option B (Erythematous nasal mucosa): This is typical due to inflammation from the allergic response. Option D (Thin watery nasal secretions): These are a hallmark of allergic rhinitis, resulting from the body’s reaction to allergens. Option E (Transverse fold across the nose): Known as the “allergic salute,” this is a result of frequently rubbing the nose upward. Dental malocclusion (Option C) is not a classic symptom of allergic rhinitis and is typically unrelated to this condition, making it the correct answer. The primary symptoms of allergic rhinitis focus on nasal and ocular manifestations rather than dental issues.

49. Topic: Bronchopulmonary Dysplasia and Respiratory Syncytial Virus (RSV) Infection

Correct Answer: E. Careful observation without the use of antibiotics or antiviral agents

Explanation: In the case of a 3-month-old infant with bronchopulmonary dysplasia who tests positive for RSV and presents with fever, wheezing, and respiratory distress: RSV infection is a viral illness; thus, antibiotics such as ampicillin (A), ceftriaxone (B), or amoxicillin (C) are not effective against viruses and are not indicated unless there is a bacterial co-infection. Ribavirin (D) is an antiviral medication that is occasionally used for severe RSV infections but is not commonly used due to its limited efficacy and potential side effects. Careful observation (E) is the most appropriate initial management for a confirmed viral infection in the absence of bacterial co-infection or other complications, as it avoids unnecessary antibiotic use and focuses on supportive care.

50. Topic: Pediatric Gastrointestinal Complications

Correct Answer: E. Achalasia

Explanation: In a 28-month-old boy with a history of tracheoesophageal fistula repair and esophageal atresia presenting with irritability, decreased appetite, and vomiting streaked with blood: Achalasia (E) is a likely diagnosis due to the history of esophageal surgery, which can predispose to motility disorders like achalasia. Achalasia can cause symptoms such as dysphagia, vomiting, and occasionally blood streaks due to esophageal irritation. Gastric ulcer (A) and esophageal varices (B) are less likely in this age group and without additional risk factors such as liver disease or NSAID use. Peptic esophagitis (C) typically presents with symptoms of reflux and esophageal irritation, but the history of esophageal surgery makes this less likely. An unknown caustic ingestion (D) would typically present with acute symptoms shortly after ingestion, not delayed symptoms as described. Therefore, achalasia (E) is the most likely diagnosis in this child based on the clinical presentation and history of esophageal surgery.

51. Topic: Pediatric Gastrointestinal Disorders

Correct Answer: E. Meckel’s diverticulum

Explanation: In a 6-week-old child presenting with streaks of red blood mixed with normal stools: Meckel’s diverticulum (E) is the most likely diagnosis. Meckel’s diverticulum is a congenital abnormality of the small intestine that can contain ectopic gastric mucosa, which may bleed intermittently and cause blood to appear in the stool. Eosinophilic colitis (A) typically presents with chronic diarrhea and may have mucous or blood in the stool, but it’s less common in infants. Hemolytic uremic syndrome (B) is characterized by hemolytic anemia, thrombocytopenia, and acute kidney injury, typically without overt gastrointestinal bleeding. Ulcerative colitis (C) is rare in infants and usually presents with bloody diarrhea, not just streaks of blood. Juvenile polyps (D) can cause rectal bleeding, but they are less common in infants compared to older children. Therefore, based on the clinical presentation of streaks of red blood mixed with normal stools in a 6-week-old child, Meckel’s diverticulum (E) is the most likely diagnosis due to its potential for intermittent gastrointestinal bleeding.

52. Topic: Irregular Heartbeat in a Healthy Child

Correct Answer: B. His echocardiogram will probably show myocardial dysfunction

Explanation: In a healthy, asymptomatic 7-year-old with an irregular heartbeat, the likelihood of myocardial dysfunction (B) is less probable because the irregular heartbeat is likely benign. Participation in gym class (A) is generally not restricted without other significant findings. Exercise testing (C) typically shows normal exercise duration with suppression of extrasystoles. Ventricular tachycardia (D) is rare in this context, making it unlikely. Therefore, option B is correct as it’s less likely for a healthy child with an irregular heartbeat to have myocardial dysfunction.

53. Topic: Noisy Breathing in a 6-week-old Baby

Correct Answer: D. Laryngomalacia

Explanation: Laryngomalacia (D) is a common cause of noisy breathing in infants, characterized by inspiratory stridor that worsens with respiratory illnesses and improves during sleep. This condition involves softening of the tissues of the larynx, leading to collapse during inspiration. Asthma (A), bronchopulmonary dysplasia (B), cystic fibrosis (C), and tuberculosis (E) are less likely causes in this age group compared to laryngomalacia, which typically presents with the described symptoms.

54. Topic: Asthma

Correct Answer: A. Its severity disappears or exacerbates with or without treatment

Explanation: Asthma (A) is a chronic condition characterized by bronchial hyperreactivity (B) and can be triggered by viral infections (C). The presence of sibilant rales (wheezing) can support the diagnosis (D). Inhaled sympathomimetics (bronchodilators) are indeed effective therapies (E). However, asthma does not typically resolve or worsen unpredictably without treatment; instead, its severity often correlates with the effectiveness of ongoing management and trigger avoidance. Therefore, statement A is incorrect as asthma usually requires consistent management to control symptoms and prevent exacerbations.

55. Topic: Assessment of Hypertension in a 14-Year-Old Boy

Correct Answer: D. To repeat the blood pressure measurement on several occasions

Explanation: It’s essential to confirm the diagnosis of hypertension in a young patient like this before proceeding with further investigations or interventions. Blood pressure measurements can vary due to factors like stress or temporary conditions. Repeating the measurement on different occasions helps to rule out white coat hypertension or other transient causes (A, B, C, E).

56. Topic: Anemia of Chronic Disease

Correct Answer: D. Iron storage in the bone marrow is increased

Explanation: The anemia of chronic disease is characterized by a complex pathophysiology where iron metabolism is altered. In this condition, iron is sequestered in macrophages of the reticuloendothelial system, including the bone marrow, leading to decreased availability for erythropoiesis. This results in normocytic or microcytic anemia with low serum iron levels (B), high serum iron binding capacity (C), and typically normal to low mean corpuscular volume (A). Iron treatment is not usually effective in correcting hemoglobin levels due to the underlying inflammatory process (E).

57. Topic: Disorders Associated with Prolonged Bleeding Time

Correct Answer: A. Hemophilia A

Explanation: Hemophilia A is a disorder characterized by deficiency or dysfunction of clotting factor VIII, leading to impaired blood clotting and prolonged bleeding time. In contrast, von Willebrand’s disease (B), aspirin-induced thrombocytopathy (C), Bernard-Soulier syndrome (D), and idiopathic thrombocytopenic purpura (E) are conditions that can lead to bleeding disorders but are not typically associated with prolonged bleeding time due to factor deficiencies.

58. Topic: Hemophilia Complications

Correct Answer: E. Hemorrhage in the tissues of the supraclavicular region

Explanation: In individuals with hemophilia, spontaneous bleeding into soft tissues can occur due to the deficiency of clotting factors, particularly factor VIII in hemophilia A. This can lead to the formation of masses or hematomas in various locations, including the supraclavicular region. These masses do not regress with treatment aimed at the primary disorder (hemophilia) because the underlying cause is the ongoing bleeding tendency rather than a neoplastic or infectious process. Non-Hodgkin lymphoma (A), metastatic neuroblastoma (B), Kaposi’s sarcoma (C), and acute non-lymphocytic leukemia (D) are less likely in the context of a mass persisting despite treatment for hemophilia and without evidence of a factor VIII inhibitor. These conditions typically require different diagnostic and therapeutic approaches compared to managing a hemorrhage in a hemophilic patient.

59. Topic: Pediatric Infectious Diseases

Correct Answer: D. Acute bacterial lymphadenitis

Explanation: Acute bacterial lymphadenitis is a common cause of fever and cervical lymphadenopathy in children. It typically presents with localized tenderness and fluctuation of lymph nodes due to suppurative inflammation. The history of fever and fluctuating left anterior cervical lymphadenopathy fits well with this diagnosis. Hodgkin’s disease (A), acute lymphoblastic leukemia (B), histiocytosis (C), and metastatic neuroblastoma (E) are less likely in this scenario. These conditions generally present with different clinical features and would require additional investigations such as imaging, biopsies, or bone marrow studies for definitive diagnosis. Hodgkin’s disease, for example, often presents with painless lymphadenopathy without fluctuation or localized tenderness. Therefore, based on the clinical presentation described, acute bacterial lymphadenitis is the most likely diagnosis in this 10-year-old girl.

60. Topic: Diabetic Ketoacidosis (DKA)

Correct Answer: B. Vomiting

Explanation: Diabetic ketoacidosis (DKA) typically develops due to a relative or absolute deficiency of insulin, leading to hyperglycemia, dehydration, and ketosis. Factors contributing to its development include: Overeating (A): Excessive intake of carbohydrates can lead to elevated blood glucose levels. Omission of insulin doses (C): Not taking insulin as prescribed can result in uncontrolled blood sugar levels. Infection (D): Illnesses, especially infections, can trigger DKA due to the release of stress hormones and increased insulin resistance. Lack of parental education (E): Inadequate understanding of diabetes management can lead to poor adherence to treatment. Incorrect Option: Vomiting (B) – While vomiting can lead to fluid and electrolyte losses, it is often a consequence rather than a cause of DKA. The primary factors causing DKA are related to insulin deficiency and not directly to vomiting. Therefore, among the factors listed, vomiting is not a primary contributor to the development of diabetic ketoacidosis. The focus should be on managing insulin therapy, dietary intake, monitoring for infections, and ensuring proper education and support for diabetes management.

61. Topic: Insulin Reaction (Hypoglycemia)

Correct Answer: A. Loss of appetite

Explanation: Insulin reaction, or hypoglycemia, occurs when blood glucose levels drop below normal. Manifestations include Sweating (B): Excessive sweating is a common symptom of hypoglycemia. Lethargy (C): Feeling tired or lethargic can occur due to low glucose levels affecting energy. Weird behavior (D): Confusion, irritability, or unusual behavior can be seen during hypoglycemia. A speech impediment (E): Slurred speech or difficulty articulating words can occur when glucose levels are low. Incorrect Option: Loss of appetite (A) Typically, hypoglycemia does not cause a loss of appetite. Instead, individuals may feel hungry or have a strong desire to eat to raise blood sugar levels. Therefore, loss of appetite is not typically associated with insulin reactions in insulin-dependent diabetic patients, making it the correct answer in this context.

62. Topic: Tuberculosis Infection in a Child

Correct Answer: C. Treatment with isoniazid for 6 months

Explanation:

In a child with a positive tuberculin skin test indicating latent tuberculosis infection without clinical or radiological signs of disease, the recommended course of action is treatment with isoniazid for 6 months. This therapy aims to prevent progression to active tuberculosis disease by eliminating latent infection. BCG vaccination (B) is given preventively but is not the correct choice here as the child already has a positive tuberculin test. Options D and E involve more aggressive treatment regimens, including corticosteroid therapy or combination therapy with multiple drugs, which are not indicated for asymptomatic latent tuberculosis infection. Simple monitoring (A) is insufficient as untreated latent tuberculosis can progress to active disease.

63. Topic: Prevention of Kernicterus in Hyperbilirubinemia

Correct Answer: B. Unconjugated bilirubin is strongly bound to albumin

Explanation: In preventing kernicterus (bilirubin encephalopathy), the binding of unconjugated bilirubin to albumin plays a crucial role. This binding reduces the free fraction of unconjugated bilirubin, which is critical because only the unbound (free) fraction can cross the blood-brain barrier and cause neurotoxicity. Options A, C, and D are incorrect because unconjugated bilirubin is fat soluble (A), weakly bound to hemoglobin (C), and can cross the blood-brain barrier if not bound to albumin (D). Option E is incorrect as cerebrospinal fluid does not metabolize bilirubin; rather, the liver is responsible for its metabolism.

64. Topic: Pediatric Head Injury – Skull Scan Findings

Correct Answer: D. A fracture of the base of the skull

Explanation: In a pediatric head injury scenario where there is blood behind the tympanic membrane (hemotympanum) following trauma, the likely finding on a skull scan would be a fracture of the base of the skull (option D). This type of fracture can lead to hemotympanum due to blood leaking into the middle ear cavity from the adjacent fracture site. Options A (subdural hematoma), B (epidural hematoma), and C (intraventricular hemorrhage) are less likely without associated symptoms such as altered consciousness or focal neurological deficits. Option E (hydrocephalus) is not directly related to the initial presentation of a head injury.

65. Here’s the explanation based on your answer:

Topic: Pediatric Nephrology – Glomerulonephritis

Correct Answer: B. Post-streptococcal glomerulonephritis

Explanation: Post-streptococcal glomerulonephritis (PSGN) is characterized by brown urine (hematuria), hypertension, and edema due to fluid retention, as well as other signs such as periorbital edema and hepatomegaly. These symptoms typically occur following a streptococcal infection, such as impetigo (skin infection caused by streptococcus). PSGN is more common in children, especially after a throat or skin infection with certain strains of streptococcus. Options A (IgA nephropathy), C (idiopathic hypercalciuria), D (pyelonephritis), and E (sexually transmitted disease) do not typically present with the classic triad of symptoms seen in PSGN, making them less likely in this scenario.

66. Topic: Muscular Disorders

Correct Answer: A. Duchenne muscular dystrophy

Explanation: Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle degeneration and weakness. It commonly presents with an awkward gait, difficulty in rising from a sitting or lying position due to proximal muscle weakness, and may exhibit scoliosis over time (hints at passive exclusion of other options). The diagnosis is typically made based on clinical signs, genetic testing, and muscle biopsy.

67. Topic: Genetic Disorders

Correct Answer: B. Turner syndrome

Explanation: Turner syndrome is characterized by primary amenorrhea (absence of menstrual periods), short stature, and abnormalities such as ulnar deviation (ulna vulgus). Individuals with Turner syndrome typically have normal intelligence quotient (IQ) but may exhibit certain learning disabilities or social difficulties. The syndrome is caused by partial or complete absence of the second sex chromosome (X), affecting females exclusively.

68. Topic: Neonatal Jaundice

Correct Answer: D. Physiological jaundice

Explanation: Physiological jaundice is a common condition in newborns due to the immaturity of the liver enzyme systems responsible for processing bilirubin. It typically appears after the first 24 hours of life, peaks around day 3-5, and resolves within 1-2 weeks without intervention. The bilirubin levels are usually below 12 mg/dL and gradually decrease as the liver matures. This type of jaundice does not require treatment unless bilirubin levels become significantly elevated.

69. Topic: Night Blindness

Correct Answer: D. Vitamin A deficiency

Explanation: Night blindness, or nyctalopia, is a condition where an individual has difficulty seeing in low light or darkness. It is a characteristic symptom of vitamin A deficiency, which plays a crucial role in the function of rhodopsin, a pigment in the retina involved in low-light vision. Deficiency in vitamin A can lead to impaired adaptation to darkness and night blindness. Adequate intake of vitamin A-rich foods or supplements is essential for maintaining healthy vision, especially in low-light conditions.

70. Based on the scenario described (a young boy with polyuria and very high blood sugar levels), the correct answer is D. Here’s why: Saline serum with hydrocortisone

Explanation: Polyuria and very high blood sugar levels suggest diabetic ketoacidosis (DKA), a serious complication of diabetes mellitus where insulin deficiency leads to hyperglycemia, ketosis, and dehydration. The treatment of choice for DKA involves fluid resuscitation with normal saline to correct dehydration and electrolyte imbalances. Additionally, insulin therapy is crucial to reverse hyperglycemia and promote glucose utilization. Hydrocortisone may be used in some cases to counteract stress-related cortisol responses and prevent adrenal insufficiency. This treatment approach addresses the fluid deficits (with normal saline), corrects electrolyte abnormalities (potentially with potassium supplementation), and provides insulin (to lower blood sugar levels).

71. Topic: Genetic Disease Mechanism

Correct Answer: C. Genetic

Explanation: In the case presented, where a boy exhibits mental retardation and learning difficulties similar to his father and uncle, the most likely mechanism for the disease is genetic. Genetic disorders are inherited conditions that can manifest with various neurological impairments, including intellectual disabilities. This aligns with the familial pattern described, indicating a genetic basis for the condition. Other options such as alpha-1 antitrypsin deficiency (A), ciliary dyskinesia (B), immune processes (D), and trinucleotide repeat disorders (E) are less likely in the context provided and are not directly associated with the familial inheritance pattern described.

72. Topic: Diagnosis of Esophageal Atresia in Newborns

Correct Answer: C. Hypersialorrhea

Explanation: In newborns, hypersialorrhea (excessive drooling or saliva accumulation) is a consistent clinical symptom that raises suspicion for the diagnosis of esophageal atresia. This occurs because the affected newborns are unable to swallow saliva due to the obstruction in the esophagus. Other symptoms such as cyanosis (A), respiratory distress (B), vomiting (D), and cough (E) can also be present but are less specific compared to hypersialorrhea, which is a hallmark sign indicative of potential esophageal atresia.

73. Topic: Complications of Infectious Mononucleosis

Correct Answer: E. Airway obstruction

Explanation: Infectious mononucleosis, caused by the Epstein-Barr virus (EBV), can lead to significant tonsillar enlargement (exudative tonsillitis), cervical lymphadenopathy (adenitis), and splenomegaly. Airway obstruction (option E) is a potential complication due to the enlargement of tonsils and adenoids, which can obstruct the airway and cause difficulty in breathing. This complication may necessitate careful monitoring and sometimes intervention to ensure the airway remains patent. While chronic fatigue (option A) is a common symptom of mononucleosis, it typically resolves within weeks to months and is not considered a complication lasting more than 6 months. Hemorrhage (option B), pneumonia (option C), and encephalitis (option D) are less frequently encountered complications compared to airway obstruction in infectious mononucleosis.

74. Based on the clinical presentation of anemia and stroke in a 9-year-old child, the most likely finding on hemoglobin electrophoresis is:

Correct Answer: D. HbF 15%

Explanation: The presence of anemia and stroke in a child strongly suggests sickle cell disease. In sickle cell disease, hemoglobin electrophoresis typically shows an elevated level of fetal hemoglobin (HbF). In this case, HbF is expected to be around 15%, reflecting the persistence of fetal hemoglobin beyond infancy due to the genetic mutation affecting the beta-globin chains. Options A (HbS 45%) and E (HbC 45%) are associated with sickle cell disease variants (HbS and HbC), but the question specifically asks for the likely finding on hemoglobin electrophoresis, where HbF elevation is characteristic. Option B (HbA 65%) is typical of normal adult hemoglobin, which is not expected in significant amounts in sickle cell disease. Option C (HbA2 15%) is associated with beta-thalassemia trait and is not directly related to the presentation of anemia and stroke in this context.

75. Topic: Febrile Seizures in a 2-year-old Boy

Correct Answer: A. Arrange for an EEG

Explanation: Febrile seizures are common in young children and are typically benign. However, given the family history of epilepsy and the recurrence of febrile seizures, an EEG (Electroencephalogram) is the most appropriate next step. EEG helps in evaluating the electrical activity in the brain, which can provide insights into the likelihood of future seizures and the need for ongoing management. Other options such as MRI (B) are less commonly indicated unless there are specific neurological concerns beyond febrile seizures. Options C, D, and E are not typically indicated in the initial evaluation of febrile seizures.

76. Topic: Haemophilus influenzae Type B Meningitis

Correct Answer: C. Treat the girl and offer antibiotics prophylactically to all family members

Explanation: Haemophilus influenzae type B (Hib) meningitis is a serious bacterial infection that can spread to close contacts, especially family members. Treatment of the affected individual with appropriate antibiotics is crucial to eradicate the infection. Offering prophylactic antibiotics to all family members helps prevent the spread of the bacteria within the household, reducing the risk of secondary infections. This approach is aimed at controlling the outbreak and protecting those at risk, making it the most appropriate management strategy in this scenario.

77. Topic: Viral Infections

Case: A 2-year-old boy presents with fever, severe sialorrhea, and swelling or mass on the left side of the neck.

Correct Answer: C. Mumps virus

Explanation: Mumps virus infection typically presents with fever, swelling of the parotid or salivary glands (parotitis), and sometimes swelling in other salivary glands such as the submandibular gland. The characteristic swelling on one side of the neck (parotid gland region) along with fever and excessive drooling (sialorrhea) are hallmark features of mumps. This viral infection is transmitted through respiratory droplets and can lead to complications like orchitis, meningitis, and pancreatitis.

78. Topic: Newborn Jaundice

Correct Answer: A. ABO incompatibility

Explanation: ABO incompatibility occurs when there is a mismatch between the mother’s and baby’s blood types, particularly with respect to the ABO blood group system. In this scenario, the newborn becomes jaundiced shortly after birth, typically within the first 24 hours. The jaundice is due to hemolysis of red blood cells as a result of antibodies crossing the placenta from the mother, causing an increased breakdown of red blood cells and subsequent indirect (unconjugated) hyperbilirubinemia. Metabolic acidosis can occur secondary to the increased bilirubin load and the effects of hemolysis. Given that the parents are both Rhesus negative, ABO incompatibility is the most likely cause of jaundice and metabolic acidosis in this newborn.

79. Topic: Childhood Exanthems

Correct Answer: B. Rubella

Explanation: Rubella, also known as German measles, typically presents with a maculopapular rash that starts on the face and spreads to the trunk and extremities. It is accompanied by fever and lymphadenopathy, commonly involving cervical and occipital lymph nodes. The characteristic feature of rubella is the presence of lymphadenopathy along with the rash. Unlike measles (option A), rubella tends to have milder symptoms and a shorter duration of fever. Scarlet fever (option C) presents with a sandpaper-like rash and is caused by group A Streptococcus. Erythema infectiosum (option D) presents with a slapped-cheek appearance and is caused by parvovirus B19. Roseola infantum (option E) presents with high fever followed by a rash and is caused by human herpesvirus 6.

80. Topic: Pediatric Abdominal Conditions

Correct Answer: B. Intussusception

Explanation: Intussusception is a common cause of bowel obstruction in infants and young children. It typically presents with sudden onset of colicky abdominal pain, vomiting, and the classic triad of currant jelly-like stools, palpable abdominal mass, and “dance sign” (pain and crying when legs are raised). This condition requires urgent medical attention due to the risk of bowel ischemia and perforation if not promptly treated. Pyloric stenosis (option C) presents with non-bilious projectile vomiting in newborns and young infants. Gastroesophageal reflux disease (option A) may present with vomiting, but without the other symptoms described here. Gastroenteritis (option D) typically presents with diarrhea, vomiting, and fever, but not with the specific signs of intussusception. Urinary infection (option E) typically presents with fever, irritability, and may have abdominal pain, but it does not cause the typical findings of intussusception.