A 10-year-old boy is brought to the emergency department by his parents because of a dull persistent headache beginning that morning. He has nausea and has vomited twice. During the past four days, the patient has had left-sided ear pain and fever, but his parents did not seek medical attention. He is from Thailand and is visiting his relatives in the United States for the summer. There is no personal or family history of serious illness. He is at the 45th percentile for height and 40th percentile for weight. He appears irritable. His temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 98/58 mm Hg. The pupils are equal and reactive to light. Lateral gaze of the left eye is limited. The left tympanic membrane is erythematous with purulent discharge. There is no nuchal rigidity. Which of the following is the most appropriate next step in management?
Q112
A 10-year-old girl is admitted to the medical floor for a respiratory infection. The patient lives in a foster home and has been admitted many times. Since birth, the patient has had repeated episodes of pain/pressure over her frontal sinuses and a chronic cough that produces mucus. She was recently treated with amoxicillin for an infection. The patient is in the 25th percentile for height and weight which has been constant since birth. Her guardians state that the patient has normal bowel movements and has been gaining weight appropriately. The patient has a history of tricuspid stenosis. She also recently had magnetic resonance imaging (MRI) of her chest which demonstrated dilation of her airways. Her temperature is 99.5°F (37.5°C), blood pressure is 90/58 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 94% on room air. Physical exam is notable for bruises along the patient's shins which the guardians state are from playing soccer. The rest of the exam is deferred because the patient starts crying. Which of the following findings is associated with this patient's most likely underlying diagnosis?
Q113
A 6-year-old girl is brought to the clinic for evaluation of malaise and low-grade fever over the past 3 days. In the last 24 hours, she developed sores and pain in her mouth. She also had vesicles on her hands and feet. Her past medical history was benign and the immunization history was up-to-date. The oral temperature was 38.1°C (100.6°F). The physical examination revealed several erythematous macules in the oropharynx and small oval vesicles with an erythematous base on the palms. What is the next best step in the management of this patient?
Q114
An 8-year-old girl is brought to the emergency department by her parents with severe difficulty in breathing for an hour. She is struggling to breathe. She was playing outside with her friends, when she suddenly fell to the ground, out of breath. She was diagnosed with asthma one year before and has since been on treatment for it. At present, she is sitting leaning forward with severe retractions of the intercostal muscles. She is unable to lie down. Her parents mentioned that she has already taken several puffs of her inhaler since this episode began but without response. On physical examination, her lungs are hyperresonant to percussion and there is decreased air entry in both of her lungs. Her vital signs show: blood pressure 110/60 mm Hg, pulse 110/min, respirations 22/min, and a peak expiratory flow rate (PEFR) of 50%. She is having difficulty in communicating with the physician. Her blood is sent for evaluation and a chest X-ray is ordered. Her arterial blood gas reports are as follows:
PaO2 50 mm Hg
pH 7.38
PaCO2 47 mm Hg
HCO3 27 mEq/L
Which of the following is the most appropriate next step in management?
Q115
A 3-year-old boy is brought to the emergency department by his mother because of a cough and mild shortness of breath for the past 12 hours. He has not had fever. He has been to the emergency department 4 times during the past 6 months for treatment of asthma exacerbations. His 9-month-old sister was treated for bronchiolitis a week ago. His father has allergic rhinitis. Current medications include an albuterol inhaler and a formoterol-fluticasone inhaler. He appears in mild distress. His temperature is 37.5°C (99.5°F), pulse is 101/min, respirations are 28/min, and blood pressure is 86/60 mm Hg. Examination shows mild intercostal and subcostal retractions. Pulmonary examination shows decreased breath sounds and mild expiratory wheezing throughout the right lung field. Cardiac examination shows no abnormalities. An x-ray of the chest shows hyperlucency of the right lung field with decreased pulmonary markings. Which of the following is the next best step in management?
Q116
A 4-year-old child is brought to a pediatric clinic with complaints of a foul-smelling, recurrent, persistent vaginal discharge that started a few days ago. The child shows increased irritability with a slightly elevated temperature. The mother says that the child plays in the house and has no contact with other children. What is the most common cause of this patient’s symptom?
Q117
A 5-year-old boy is brought to the physician because of a nonpruritic rash on his face that began 5 days ago. It started as a bug bite on his chin that then developed into small pustules with surrounding redness. He has not yet received any routine childhood vaccinations. Physical examination shows small, clustered lesions with gold crusts along the lower lip and chin and submandibular lymphadenopathy. At a follow-up examination 2 weeks later, his serum anti-deoxyribonuclease B antibody titer is elevated. This patient is at greatest risk for which of the following complications?
Q118
A 12-year-old boy presents with recurrent joint pain that migrates from joint to joint and intermittent fever for the last several weeks. He also says that he has no appetite and has been losing weight. The patient is afebrile, and vital signs are within normal limits. On physical examination, he is pale with diffuse petechial bleeding and bruises on his legs. An abdominal examination is significant for hepatosplenomegaly. Ultrasound of the abdomen confirms hepatosplenomegaly and also shows multiple enlarged mesenteric lymph nodes. A complete blood count (CBC) shows severe anemia and thrombocytopenia with leukocytosis. Which of the following is the most likely diagnosis in this patient?
Q119
A 12-year-old boy is brought in by his mother to the emergency department. He has had abdominal pain, fever, nausea, vomiting, and loss of appetite since yesterday. At first, the mother believed it was just a "stomach flu," but she is growing concerned about his progressive decline. Vitals include: T 102.3 F, HR 110 bpm, BP 120/89 mmHg, RR 16, O2 Sat 100%. Abdominal exam is notable for pain over the right lower quadrant. What is the next best step in management in addition to IV hydration and analgesia?
Q120
A 7-year-old boy with a past medical history significant only for prior head lice infection presents to the clinic after being sent by the school nurse for a repeat lice infection. The boy endorses an itchy scalp, but a review of systems is otherwise negative. After confirming the child’s diagnosis and sending him home with appropriate treatment, the school nurse contacts the clinic asking for recommendations on how to prevent future infection. Which of the following would be the best option to decrease the likelihood of lice reinfestation?
Infectious Disease US Medical PG Practice Questions and MCQs
Question 111: A 10-year-old boy is brought to the emergency department by his parents because of a dull persistent headache beginning that morning. He has nausea and has vomited twice. During the past four days, the patient has had left-sided ear pain and fever, but his parents did not seek medical attention. He is from Thailand and is visiting his relatives in the United States for the summer. There is no personal or family history of serious illness. He is at the 45th percentile for height and 40th percentile for weight. He appears irritable. His temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 98/58 mm Hg. The pupils are equal and reactive to light. Lateral gaze of the left eye is limited. The left tympanic membrane is erythematous with purulent discharge. There is no nuchal rigidity. Which of the following is the most appropriate next step in management?
A. Intravenous ceftriaxone and clindamycin therapy
B. Lumbar puncture
C. MRI of the brain (Correct Answer)
D. Intravenous cefazolin and metronidazole therapy
E. Cranial burr hole evacuation
Explanation: ***MRI of the brain***
- The patient's presentation with **headache**, **nausea**, **vomiting**, recent **ear infection** (otitis media), **fever**, and **abducens nerve palsy** (limited lateral gaze of the left eye) is highly suggestive of an intracranial complication, such as a **brain abscess** or **epidural abscess**, secondary to the uncontrolled otitis media.
- An MRI of the brain is the **most sensitive and specific imaging modality** for detecting intracranial abscesses, which are critical to diagnose promptly due to their potential for surgical drainage and targeted antibiotic therapy.
*Intravenous ceftriaxone and clindamycin therapy*
- While broad-spectrum antibiotics are necessary, they should be initiated **after establishing a definitive diagnosis and ruling out conditions requiring immediate surgical intervention**.
- Without imaging, there's a risk of delaying crucial surgical management for a contained abscess or empyema.
*Lumbar puncture*
- A lumbar puncture is **contraindicated** in the presence of focal neurological deficits (like **abducens nerve palsy**) and symptoms of **increased intracranial pressure** (headache, nausea, vomiting), as it carries a significant risk of **herniation** if there's a mass lesion.
- Imaging should always precede LP in such cases.
*Intravenous cefazolin and metronidazole therapy*
- Cefazolin has **poor penetration into the CNS**, making it an inadequate choice for suspected intracranial infection.
- While metronidazole targets anaerobes common in brain abscesses, the overall regimen is not optimal, and imaging is still the priority.
*Cranial burr hole evacuation*
- This is a definitive surgical treatment for a brain abscess but should only be performed **after the abscess has been localized and characterized by imaging**.
- Performing a burr hole without prior imaging would be a blind procedure and is not the appropriate next step in diagnosis and management.
Question 112: A 10-year-old girl is admitted to the medical floor for a respiratory infection. The patient lives in a foster home and has been admitted many times. Since birth, the patient has had repeated episodes of pain/pressure over her frontal sinuses and a chronic cough that produces mucus. She was recently treated with amoxicillin for an infection. The patient is in the 25th percentile for height and weight which has been constant since birth. Her guardians state that the patient has normal bowel movements and has been gaining weight appropriately. The patient has a history of tricuspid stenosis. She also recently had magnetic resonance imaging (MRI) of her chest which demonstrated dilation of her airways. Her temperature is 99.5°F (37.5°C), blood pressure is 90/58 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 94% on room air. Physical exam is notable for bruises along the patient's shins which the guardians state are from playing soccer. The rest of the exam is deferred because the patient starts crying. Which of the following findings is associated with this patient's most likely underlying diagnosis?
A. Social withdrawal and avoidance of eye contact
B. Hypocalcemia
C. Repeat sinus infections secondary to seasonal allergies
D. Diastolic murmur best heard along the right lower sternal border
E. Increased chloride in the patient's sweat (Correct Answer)
Explanation: ***Increased chloride in the patient's sweat***
- The patient's history of recurrent respiratory infections, chronic productive cough, frontal sinus pain, and **bronchiectasis** (dilated airways on MRI) are highly suggestive of **cystic fibrosis**.
- **Elevated sweat chloride** is the hallmark diagnostic test for cystic fibrosis, reflecting defective chloride transport in exocrine glands.
*Social withdrawal and avoidance of eye contact*
- These are features associated with **autism spectrum disorder**, which is unrelated to the patient's respiratory and sinus symptoms.
- While possible as a co-occurring condition, it is not directly linked to the most likely **underlying diagnosis** described.
*Hypocalcemia*
- **Hypocalcemia** is typically associated with conditions like **hypoparathyroidism** or severe **vitamin D deficiency**.
- It is not a characteristic feature or direct complication of cystic fibrosis.
*Repeat sinus infections secondary to seasonal allergies*
- While seasonal allergies can cause sinus issues, the patient's history of **chronic, productive cough**, and **bronchiectasis** points to a more severe underlying condition like cystic fibrosis, not just allergies.
- Cystic fibrosis patients often have chronic sinusitis due to thick, inspissated mucus, not primarily due to allergens.
*Diastolic murmur best heard along the right lower sternal border*
- A diastolic murmur at the right lower sternal border might suggest **aortic regurgitation** or a specific type of **pulmonary regurgitation**, but it is not characteristic of the patient's known tricuspid stenosis.
- The patient has **tricuspid stenosis**, which typically causes a mid-diastolic murmur best heard at the left lower sternal border, often increasing with inspiration. This finding is unrelated to cystic fibrosis.
Question 113: A 6-year-old girl is brought to the clinic for evaluation of malaise and low-grade fever over the past 3 days. In the last 24 hours, she developed sores and pain in her mouth. She also had vesicles on her hands and feet. Her past medical history was benign and the immunization history was up-to-date. The oral temperature was 38.1°C (100.6°F). The physical examination revealed several erythematous macules in the oropharynx and small oval vesicles with an erythematous base on the palms. What is the next best step in the management of this patient?
A. Supportive care (Correct Answer)
B. Corticosteroids
C. Penicillin
D. Ribavirin
E. Aspirin
Explanation: ***Supportive care***
- This presentation is consistent with **hand-foot-and-mouth disease (HFMD)**, a common viral illness caused by **Coxsackievirus** or **Enterovirus 71**.
- HFMD is typically **self-limiting**, and management focuses on **symptomatic relief** with antipyretics, analgesics, and hydration.
*Corticosteroids*
- Corticosteroids are generally **contraindicated** in uncomplicated viral infections like HFMD, as they can **suppress the immune response** and potentially prolong the illness or lead to secondary infections.
- They are primarily used for inflammatory conditions or severe allergic reactions.
*Penicillin*
- Penicillin is an **antibiotic** and is ineffective against viral infections such as HFMD.
- Using antibiotics inappropriately can contribute to **antibiotic resistance** and may cause adverse effects.
*Ribavirin*
- Ribavirin is an **antiviral agent** used for specific viral infections like **Hepatitis C** and **RSV**.
- It is **not indicated** for the treatment of HFMD, as HFMD is typically mild and self-resolving.
*Aspirin*
- Aspirin is generally **contraindicated in children** due to the risk of **Reye's syndrome**, especially after viral infections.
- While it has antipyretic and analgesic properties, safer alternatives like acetaminophen or ibuprofen are preferred for fever and pain in children.
Question 114: An 8-year-old girl is brought to the emergency department by her parents with severe difficulty in breathing for an hour. She is struggling to breathe. She was playing outside with her friends, when she suddenly fell to the ground, out of breath. She was diagnosed with asthma one year before and has since been on treatment for it. At present, she is sitting leaning forward with severe retractions of the intercostal muscles. She is unable to lie down. Her parents mentioned that she has already taken several puffs of her inhaler since this episode began but without response. On physical examination, her lungs are hyperresonant to percussion and there is decreased air entry in both of her lungs. Her vital signs show: blood pressure 110/60 mm Hg, pulse 110/min, respirations 22/min, and a peak expiratory flow rate (PEFR) of 50%. She is having difficulty in communicating with the physician. Her blood is sent for evaluation and a chest X-ray is ordered. Her arterial blood gas reports are as follows:
PaO2 50 mm Hg
pH 7.38
PaCO2 47 mm Hg
HCO3 27 mEq/L
Which of the following is the most appropriate next step in management?
A. Intravenous corticosteroid (Correct Answer)
B. Inhaled corticosteroid
C. Mechanical ventilation
D. Methacholine challenge test
E. Inhaled β-agonist
Explanation: ***Intravenous corticosteroid***
- The patient exhibits severe asthma exacerbation with **poor response to inhaled β-agonists**, marked respiratory distress, and an alarming **PEFR of 50%**.
- **Intravenous corticosteroids** are crucial in this scenario to reduce airway inflammation and prevent progression to respiratory failure.
*Inhaled corticosteroid*
- While essential for **long-term asthma control**, inhaled corticosteroids are **not effective enough for acute, severe exacerbations** due to their slower onset of action.
- The patient's inability to effectively inhale deeply due to distress also limits the utility of inhaled delivery in this emergency.
*Mechanical ventilation*
- Mechanical ventilation is a **last-resort intervention** for impending respiratory failure, indicated by signs like declining consciousness, hypercapnia, or respiratory arrest.
- While concerning, the patient's current ABG with a **near-normal pH (7.38)** despite hypercapnia suggests she is not yet in full respiratory failure, and less invasive measures should be initiated first.
*Methacholine challenge test*
- The methacholine challenge test is used to **diagnose asthma in stable patients** with normal spirometry, by assessing airway hyperresponsiveness.
- It is **absolutely contraindicated** in an acute, severe asthma exacerbation as it could worsen bronchoconstriction and respiratory distress.
*Inhaled β-agonist*
- The patient has **already taken several puffs of her inhaler** (likely a β-agonist) without response, indicating **refractory bronchospasm**.
- While initially appropriate, repeated administration when ineffective suggests the need for other therapeutic interventions to address the underlying inflammation.
Question 115: A 3-year-old boy is brought to the emergency department by his mother because of a cough and mild shortness of breath for the past 12 hours. He has not had fever. He has been to the emergency department 4 times during the past 6 months for treatment of asthma exacerbations. His 9-month-old sister was treated for bronchiolitis a week ago. His father has allergic rhinitis. Current medications include an albuterol inhaler and a formoterol-fluticasone inhaler. He appears in mild distress. His temperature is 37.5°C (99.5°F), pulse is 101/min, respirations are 28/min, and blood pressure is 86/60 mm Hg. Examination shows mild intercostal and subcostal retractions. Pulmonary examination shows decreased breath sounds and mild expiratory wheezing throughout the right lung field. Cardiac examination shows no abnormalities. An x-ray of the chest shows hyperlucency of the right lung field with decreased pulmonary markings. Which of the following is the next best step in management?
A. Azithromycin therapy
B. Racemic epinephrine
C. Albuterol nebulization
D. CT of the lung
E. Bronchoscopy (Correct Answer)
Explanation: ***Bronchoscopy***
- The patient's history of recurrent respiratory symptoms, unilateral wheezing and decreased breath sounds, and radiological findings of **unilateral hyperlucency** and **decreased pulmonary markings** strongly suggest a **foreign body aspiration**.
- **Bronchoscopy** is both diagnostic and therapeutic in this situation, allowing for direct visualization and removal of the foreign body.
*Azithromycin therapy*
- This is an **antibiotic** and would be used for bacterial infections, which are not indicated here given the clinical picture of a suspected foreign body.
- Antibiotics are not effective for mechanical obstruction of the airway.
*Racemic epinephrine*
- Racemic epinephrine is used for conditions like **croup** to reduce airway edema.
- It would not address an inhaled **foreign body**, which is a mechanical obstruction.
*Albuterol nebulization*
- While albuterol is used for bronchospasm, the unilateral nature of the findings and the history of recurrent issues point away from simple asthma exacerbation.
- Albuterol would likely not relieve the obstruction caused by a **foreign body**.
*CT of the lung*
- While CT could help identify a foreign body, it exposes the child to **radiation** and is not the definitive treatment.
- Bronchoscopy offers both diagnosis and immediate treatment, making it superior to CT as the *next best step*.
Question 116: A 4-year-old child is brought to a pediatric clinic with complaints of a foul-smelling, recurrent, persistent vaginal discharge that started a few days ago. The child shows increased irritability with a slightly elevated temperature. The mother says that the child plays in the house and has no contact with other children. What is the most common cause of this patient’s symptom?
A. Sexual abuse
B. Clear cell carcinoma of the cervix
C. Foreign body in the vagina (Correct Answer)
D. Sarcoma botryoides
E. Congenital rectovaginal fistula
Explanation: ***Foreign body in the vagina***
- A persistent, foul-smelling vaginal discharge in a young child is highly suggestive of a **foreign body** in the vagina, which can cause irritation, inflammation, and secondary infection.
- Young children, due to their curiosity, may insert small objects into their vaginas, leading to these characteristic symptoms.
*Sexual abuse*
- While sexual abuse can cause vaginal discharge, pain, or bleeding, the primary presentation described (foul-smelling, persistent discharge with no mention of trauma or other suspicious findings) does not exclusively point to this, especially without other signs of abuse or clear epidemiological risk factors.
- It often involves signs of trauma, STIs, or psychological distress, which are not explicitly highlighted in this case.
*Clear cell carcinoma of the cervix*
- This is an extremely rare malignancy in young children and is more typically associated with **DES exposure in utero**.
- It usually presents with painless vaginal bleeding or clear discharge, not typically a foul-smelling, persistent discharge in a 4-year-old without such exposure history.
*Sarcoma botryoides*
- This is a rare, aggressive form of **rhabdomyosarcoma** that typically presents with a rapidly growing, grape-like mass protruding from the vagina, often accompanied by bleeding or a bloody discharge.
- While it can cause discharge, the clinical picture of a persistent, foul-smelling discharge without mention of a visible mass makes a foreign body more likely.
*Congenital rectovaginal fistula*
- A rectovaginal fistula connects the rectum and vagina, typically causing **fecal material** or **gas** to pass through the vagina, leading to irritation and often a discharge with a distinctly fecal odor.
- While it causes persistent discharge and may be foul-smelling, the description of general "foul-smelling" rather than distinctly fecal suggests other causes first, and it's a congenital anomaly often presenting earlier or with more distinct symptoms.
Question 117: A 5-year-old boy is brought to the physician because of a nonpruritic rash on his face that began 5 days ago. It started as a bug bite on his chin that then developed into small pustules with surrounding redness. He has not yet received any routine childhood vaccinations. Physical examination shows small, clustered lesions with gold crusts along the lower lip and chin and submandibular lymphadenopathy. At a follow-up examination 2 weeks later, his serum anti-deoxyribonuclease B antibody titer is elevated. This patient is at greatest risk for which of the following complications?
A. Reactive arthritis
B. Shingles
C. Orchitis
D. Myocarditis
E. Glomerulonephritis (Correct Answer)
Explanation: ***Glomerulonephritis***
- The patient's presentation of a **rash with golden crusts** and pustules, followed by an **elevated anti-deoxyribonuclease B (anti-DNase B) titer**, is highly suggestive of a recent **Streptococcus pyogenes** (Group A Streptococcus) skin infection, specifically **impetigo**.
- **Post-streptococcal glomerulonephritis** (PSGN) is a known complication of GAS skin infections and is characterized by renal damage, often presenting with hematuria, proteinuria, and edema, thus making it the greatest risk in this scenario.
*Reactive arthritis*
- While reactive arthritis can be triggered by *Streptococcus pyogenes* infections, it is much more commonly associated with **genitourinary or gastrointestinal infections** (e.g., *Chlamydia*, *Shigella*, *Salmonella*).
- The immune response in reactive arthritis typically involves **HLA-B27** and presents with an inflammatory arthritis, often affecting large joints, which is not the primary concern following impetigo.
*Shingles*
- **Shingles** (herpes zoster) is caused by the **reactivation of the varicella-zoster virus (VZV)**, which lies dormant in sensory ganglia after a primary chickenpox infection.
- The clinical presentation of **impetigo with golden crusts** and subsequent anti-DNase B elevation does not indicate a VZV infection or its reactivation.
*Orchitis*
- **Orchitis**, inflammation of the testicles, is most commonly associated with viral infections, particularly the **mumps virus**, especially in unvaccinated individuals.
- The described skin infection and elevated anti-DNase B titer are indicative of a **streptococcal infection**, not mumps, and therefore orchitis is not a primary risk factor in this case.
*Myocarditis*
- While **rheumatic fever**, a complication of **Streptococcus pyogenes** pharyngeal infections, can lead to **myocarditis** (rheumatic carditis), it is **rarely if ever a complication of GAS skin infections (impetigo)**.
- The elevated anti-DNase B titer points to a skin infection, but without evidence of a preceding pharyngeal infection, the risk of rheumatic fever and subsequent myocarditis is very low.
Question 118: A 12-year-old boy presents with recurrent joint pain that migrates from joint to joint and intermittent fever for the last several weeks. He also says that he has no appetite and has been losing weight. The patient is afebrile, and vital signs are within normal limits. On physical examination, he is pale with diffuse petechial bleeding and bruises on his legs. An abdominal examination is significant for hepatosplenomegaly. Ultrasound of the abdomen confirms hepatosplenomegaly and also shows multiple enlarged mesenteric lymph nodes. A complete blood count (CBC) shows severe anemia and thrombocytopenia with leukocytosis. Which of the following is the most likely diagnosis in this patient?
A. Chronic leukemia
B. Tuberculosis of the bone marrow
C. Acute leukemia (Correct Answer)
D. Immunologic thrombocytopenic purpura
E. Aplastic anemia
Explanation: ***Acute leukemia***
- The combination of **migratory joint pain**, **fever**, **weight loss**, **hepatosplenomegaly**, **petechiae**, **bruises**, and **lymphadenopathy** in a child points strongly to acute leukemia.
- **Severe anemia**, **thrombocytopenia**, and **leukocytosis** on CBC are classic hematologic features of acute leukemia, reflecting bone marrow infiltration.
*Chronic leukemia*
- **Chronic leukemias** are rare in children and typically have a slower, more indolent onset, which is inconsistent with the patient's acute presentation of symptoms.
- While leukocytosis can be present, chronic leukemias usually do not present with the severe, widespread systemic and hematologic abnormalities seen here in an acute fashion.
*Tuberculosis of the bone marrow*
- While bone marrow tuberculosis can cause **fever**, **weight loss**, and **anemia**, it typically presents with granulomas in the bone marrow and less commonly with the dramatic leukocytosis and marked hepatosplenomegaly seen here.
- **Petechiae** and **bruises** due to severe thrombocytopenia are less common as primary presenting features compared to leukemia.
*Immunologic thrombocytopenic purpura*
- **ITP** primarily causes **thrombocytopenia**, leading to petechiae and bruising, but it does not explain the **joint pain**, **fever**, **hepatosplenomegaly**, **lymphadenopathy**, or especially the **severe anemia** and **leukocytosis**.
- Other cell lines are typically normal in ITP, differentiating it from a systemic bone marrow disorder.
*Aplastic anemia*
- **Aplastic anemia** presents with **pancytopenia** (anemia, thrombocytopenia, and leukopenia), meaning a decrease in all blood cell lines.
- This patient presents with **leukocytosis** (increased white blood cells), which directly contradicts the definition of aplastic anemia.
Question 119: A 12-year-old boy is brought in by his mother to the emergency department. He has had abdominal pain, fever, nausea, vomiting, and loss of appetite since yesterday. At first, the mother believed it was just a "stomach flu," but she is growing concerned about his progressive decline. Vitals include: T 102.3 F, HR 110 bpm, BP 120/89 mmHg, RR 16, O2 Sat 100%. Abdominal exam is notable for pain over the right lower quadrant. What is the next best step in management in addition to IV hydration and analgesia?
A. Upright and supine abdominal radiographs
B. Abdominal MRI with gadolinium contrast
C. Abdominal CT scan with IV contrast
D. Right lower quadrant ultrasound (Correct Answer)
E. Abdominal CT scan with IV and PO contrast
Explanation: ***Right lower quadrant ultrasound***
- In a 12-year-old boy with suspected **appendicitis**, **ultrasound** is the preferred initial imaging modality due to its **lack of radiation** and high diagnostic accuracy in this population.
- It effectively identifies an inflamed **appendix**, periappendiceal fluid, and other relevant findings while avoiding radiation exposure, which is particularly important in children.
*Upright and supine abdominal radiographs*
- **Plain abdominal X-rays** are generally not useful for diagnosing appendicitis as they often do not visualize the appendix directly.
- While they can rule out other causes of abdominal pain like **bowel obstruction** or **perforation** (free air), they lack the sensitivity and specificity for appendicitis.
*Abdominal MRI with gadolinium contrast*
- **MRI** is an excellent alternative to CT, especially in pregnant patients, but it is **less readily available** and consumes more time than ultrasound in an emergent setting for a pediatric patient.
- Though it provides good soft tissue detail without radiation, its **cost and accessibility** make it less practical as a first-line imaging test for suspected appendicitis in children.
*Abdominal CT scan with IV contrast*
- An **abdominal CT scan with IV contrast** is highly accurate for diagnosing appendicitis, but it involves significant **ionizing radiation**, which should be minimized in pediatric patients.
- It is typically reserved for cases where ultrasound findings are equivocal or other diagnoses are strongly suspected, or when the patient is older or body habitus limits ultrasound utility.
*Abdominal CT scan with IV and PO contrast*
- Adding **oral contrast** to a CT scan significantly increases the time before imaging can be performed, which is not ideal in an acute emergency like suspected appendicitis.
- While it can help delineate bowel loops, the additional contrast and associated delay are usually **unnecessary** for diagnosing appendicitis and further expose the child to radiation.
Question 120: A 7-year-old boy with a past medical history significant only for prior head lice infection presents to the clinic after being sent by the school nurse for a repeat lice infection. The boy endorses an itchy scalp, but a review of systems is otherwise negative. After confirming the child’s diagnosis and sending him home with appropriate treatment, the school nurse contacts the clinic asking for recommendations on how to prevent future infection. Which of the following would be the best option to decrease the likelihood of lice reinfestation?
A. Encourage family to move out of their home
B. Treatment with oral albendazole
C. Treatment with topical clindamycin
D. Observation with close monitoring
E. Environmental measures including washing bedding and clothing in hot water and avoiding sharing personal items (Correct Answer)
Explanation: ***Environmental measures including washing bedding and clothing in hot water and avoiding sharing personal items***
- The **most important prevention strategy** for head lice in school settings is **avoiding sharing personal items** such as hats, combs, brushes, hair accessories, headphones, and clothing.
- Head lice are transmitted primarily through **direct head-to-head contact**, but can also spread via **fomites** (contaminated objects), particularly items that touch the head.
- Teaching children not to share personal items and maintaining proper hygiene practices are **practical, evidence-based interventions** that schools can implement.
- While lice cannot survive long off the human host (typically 1-2 days), washing potentially contaminated bedding and clothing in hot water (>130°F) provides additional reassurance and is a reasonable adjunct measure.
- This represents the **best actionable advice** for a school nurse seeking to prevent future outbreaks.
*Observation with close monitoring*
- While surveillance and early detection are important components of lice management, **observation alone is a passive strategy** that does not actively prevent transmission.
- Close monitoring helps identify cases early but does not address the behavioral and environmental factors that lead to spread.
- This should be part of a comprehensive approach but is not the primary prevention method.
*Treatment with oral albendazole*
- **Albendazole** is an anthelmintic used for intestinal parasites (e.g., ascariasis, hookworm, pinworm) and has **no role** in head lice treatment or prevention.
- For difficult-to-treat pediculosis, **oral ivermectin** may be considered, but prophylactic treatment is not recommended.
*Treatment with topical clindamycin*
- **Clindamycin** is an antibiotic effective against bacterial infections, particularly anaerobes and some gram-positive organisms.
- It has **no efficacy** against head lice, which are ectoparasites requiring insecticidal treatments (e.g., permethrin, malathion, benzyl alcohol).
*Encourage family to move out of their home*
- This is an **extreme, unnecessary, and inappropriate recommendation** for head lice.
- Head lice are **not a sign of poor hygiene** or unclean living conditions; they can affect anyone regardless of socioeconomic status.
- Lice are spread through direct contact, not through environmental contamination of homes, making relocation completely unwarranted.
