A7-month-old baby presents with a history of constipation for 1 month. He has one hard stool every week. He has been well otherwise. His physical examination is normal. Which of the following is the most likely cause of his problem?
Answer(s): C
Hypocalcemia is not a cause of constipation. On the contrary, it increases irritability of nerve cells and may result in diarrhea. Hypothyroidism, lead poisoning, and Hirschsprung disease all may be associated with constipation. Congenital hypothyroidism and Hirschsprung disease (a congenital disorder characterized by regional absence of ganglion cells from the myenteric plexus of the colon) present at birth. Lead poisoning is more common after the child becomes mobile. Functional constipation is the most common cause of constipation at this age. It is usually due to dietary factors.
A10-year-old boy presents with a 3- to 4-day history of left ear pain. He is afebrile; he has had no symptoms of cold or cough. He has been swimming daily. On physical examination, there is pain on moving the pinna and the tragus. There is erythema and swelling of the ear canal; the tympanic membrane is obscured by thick white discharge.Which of the following is the most likely diagnosis?
Answer(s): A
Otitis externa is an infection of the external ear canal. Predisposing factors include excessive wetness (swimming), dryness (lack of protective cerumen), trauma (foreign body), and other skin pathology (eczema). It is characterized by pain, accentuated by moving the pinna and especially the tragus; edema and inflammation of the canal; and discharge. Furuncles usually cause a localized swelling or papule in the hairbearing part of the canal. If the tympanic membrane is not visualized, otitis media is hard to differentiate from otitis externa. Otitis media does not cause pain with movement of the pinna. In severe otitis externa, the periauricular edema may push the pinna forward; this may be confused with mastoiditis. In mastoiditis, however, the postauricular fold is usually obliterated. There is often a history of otitis media and hearing loss and tenderness over the mastoid antrum.
A10-year-old boy presents with a 3- to 4-day history of left ear pain. He is afebrile; he has had no symptoms of cold or cough. He has been swimming daily. On physical examination, there is pain on moving the pinna and the tragus. There is erythema and swelling of the ear canal; the tympanic membrane is obscured by thick white dischargeWhich of the following is the most likely organism involved in this case?
Answer(s): D
F. aeruginosa is the most common agent involved in external otitis. The other organisms listed may also be isolated.
A specific pattern of abnormalities has been identified among infants born to mothers who consume moderate-to-large amounts of alcohol during their pregnancies. Which of the following abnormalities is characteristic of these infants?
Answer(s): E
The characteristics of fetal alcohol syndrome include: A. persistent deficient growth affecting weight, height, and head circumference and beginning in utero; B. such facial abnormalities as micrognathia, short palpebral fissures, and a thin upper lip; (C) cardiac abnormalities, commonly septal defects; (D) minor limb abnormalities with some restriction of mobility and some alteration in palmar crease patterns; and (E) mental deficiency ranging from mild to severe. There is a decided relationship between the extent of abnormalities and the degree of mental retardation. Affected infants may present with hypoglycemia and alcohol withdrawal symptoms which may last for 4872 hours. Immediate management of these infants consists of correction of the hypoglycemia. Ongoing monitoring of the child's development is essential.Prevention by restriction of alcohol consumption during pregnancy is advised.
A 4-year-old girl presents to the emergency department with fever and a petechial rash. A sepsis workup is performed, and IV antibiotics are administered. Gram-negative diplococci are identified in the CSF. Which of the following is true of this condition?
Meningococcemia is a fulminant systemic rapidly progressing infection that results in shock and is followed by death in 20% of afflicted children. The presence of meningitis has been shown to increase the survival rate to approximately 95%. Sensorineural deafness is the most common residual following bacterial meningitis. Penicillin, ampicillin, or a third-generation cephalosporin would be an appropriate antibiotic to choose for treatment. Vancomycin's spectrum of activity is limited to gram-positive organisms.
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