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A 2-month-old infant is brought to the emergency department with irritability and lethargy. The parents state that he was well until he rolled off the couch on to the floor yesterday. On examination, he is inconsolable and afebrile. The fontanels are full and tense. He has a generalized tonic-clonic seizure. Which of the following is the most important initial diagnostic study to order?

  1. serum calcium, phosphorus, and magnesium levels
  2. analysis of cerebrospinal fluid (CSF)
  3. cranial computed tomography (CT) scan
  4. serum ammonia level
  5. serum acetaminophen level

Answer(s): C

Explanation:

Though infection must be considered as an etiology, acute trauma is more likely in this scenario. This case represents the classic picture of the shaken baby syndrome which produces intracranial trauma without obvious external findings. This infant is critically ill and lacks preceding illness or constitutional symptoms.
The tense fontanels reflect increased intracranial pressure. Acranial CT scan may show diffuse edema or a localized lesion, such as a subdural hemorrhage. Metabolic causes of seizures do not cause increased intracranial pressure. Acetaminophen toxicity does not cause CNS symptoms.



A 7-year-old girl presents with hives, which developed after a bee sting. She has no other symptoms. The hives resolve with diphenhydramine. Which of the following is the most appropriate management?

  1. Write a prescription for diphenhydramine in case she is bitten again.
  2. Provide an Epi-pen Jr (epinephrine auto injector) to be carried at all times, as well as a prescription for diphenhydramine.
  3. Admit to the hospital for observation for delayed hypersensitivity symptoms.
  4. Refer her to an allergist for desensitization.
  5. Order a skin-prick test with hymenoptera venom.

Answer(s): B

Explanation:

The insect order Hymenoptera includes ants, bees, and wasps. Their venom usually only causes a local reaction. About 14% of the population is sensitized to the venom and at risk for immediate hypersensitivity reactions. Reactions may include urticaria, angioedema, wheezing, or hypotension. Severe reactions should be treated with IV fluids, oxygen, and epinephrine. Although the child responded well to diphenhydramine, because there was a systemic reaction, it is advisable to carry an Epi-pen Jr at all times.
Only children with life-threatening systemic reactions need to be referred for desensitization. Testing IgE or skinprick test with Hymenoptera venom is not predictive of future systemic reactions.



A 2-year-old boy has had a purulent drainage from the right nostril for a week. He is afebrile and has had no associated symptoms, such as cough. Which of the following is the most likely diagnosis?

  1. sinusitis
  2. nasal polyps
  3. an upper respiratory infection
  4. a foreign body in the right nostril
  5. allergic rhinitis

Answer(s): D

Explanation:

Children frequently insert foreign bodies into the nose. Initial symptoms are local obstruction, sneezing, and pain. Subsequently, there is swelling and infection leading to a purulent, malodorous, and often bloody discharge. The infection clears after removal of the foreign body. Nasal polyps cause obstruction of the nasal passages, hyponasal speech, and mouth breathing; gray, grape-like masses can be visualized on nasal examination. An upper respiratory infection is usually suggested by a careful history. Initial symptoms include a scratchy throat, followed by development of thin nasal discharge and sneezing. Myalgia, low- grade fever, headache,
malaise, and decreased appetite may be present. By the 2nd or 3rd day, the discharge becomes thicker and more purulent. Cough is common. Symptoms usually resolve by 710 days. Adolescents with sinusitis may have classic symptoms of headache and sinus tenderness. In children, cough and nasal discharge are common; the cough is worse when supine. If upper respiratory infection symptoms persist without improvement for >10 days, sinusitis should be considered. A more acute form may occur, with a shorter duration and more severe symptoms such as fever >39°C, purulent nasal discharge, headache, and eye swelling. Children with allergic rhinitis present with sneezing, clear watery, rhinorrhea, and itching of the nose, palate, pharynx, and eyes. Itching, redness, and tearing of the eyes may be present. This occurs in response to exposure to an allergen such as pollen, mold spores, and animal or mite antigens



A 5-year-old boy has a history of bed-wetting about four to five times a week. He has recently begun to attend kindergarten. He was toilet trained (dry during the day) by age 3 but has never been consistently dry at night. He denies any dysuria or frequency. There is no history of increased thirst or frequent urination. The urinalysis is negative for blood, protein, glucose, or ketones; there are no white cells or bacteria; the specific gravity is 1.020. Which of the following is the most likely diagnosis?

  1. a urinary tract infection (UTI)
  2. primary nocturnal enuresis
  3. secondary enuresis caused by stress of the new school
  4. diabetes mellitus
  5. diabetes insipidus

Answer(s): B

Explanation:

Enuresis may be primary (75%) where nocturnal control was never achieved; secondary enuresis (25%) is when the child was dry at night for at least a few months. Nocturnal enuresis is more common in boys, and family history is positive in at least 50%. This may affect as much as 20% of children at age 5 years, and it spontaneously stops in at least 15% of affected children every year. Psychological factors are often involved in secondary enuresis. A careful history should be obtained to rule out such organic factors as UTI (dysuria, frequency, urgency). Children with diabetes insipidus or diabetes mellitus have polydipsia and polyuria. Urinalysis should be considered to rule out an organic cause. In diabetes mellitus, urinalysis may reveal glycosuria and ketonuria. Aurinespecific gravity of >1.015 makes diabetes insipidus unlikely.






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