Otitis media occurring during the first 8 weeks of life deserves special consideration, because the bacteria responsible for infections during this time may be different from those that affect older infants and children. Which of the following organisms is the most likely to cause otitis media in these infants?
Answer(s): B
F. trachomatis is considered an unusual cause of otitis media at any age. N. gonorrhoeae causes conjunctivitis in the newborn. Syphilis and toxoplasmosis cause congenital infections. E. coli is one of the neonatal pathogens that also cause otitis media in neonates. The symptoms of otitis media in newborns are often similar to those of sepsis; they are subtle and nonspecific and may include poor feeding, lethargy, vomiting, or diarrhea. Once the diagnosis is established, the initial therapy should be similar to that for neonatal sepsis, such as parenteral ampicillin and cefotaxime. Under ideal circumstances, the results of cultures obtained by tympanocentesis may then allow further treatment with a more specific antibiotic of low toxicity. Older infants may respond well to oral therapy but require frequent observation.
Among the conditions that cause edema of the eyelids is orbital cellulitis. This is a serious infection that must be recognized early and treated aggressively if complications are to be avoided. Which of the following features is useful in differentiating orbital cellulitis from periorbital (preseptal) cellulitis?
Answer(s): A
Proptosis and limitation of extraocular motility distinguish orbital cellulitis from periorbital cellulitis. Fever, lid swelling, redness of the eye, and leukocytosis generally are present in either condition. Orbital cellulitis (infection within the orbit) may follow directly from a wound near the orbit or may result from bacteremia, but the most common source involves extension from the paranasal sinuses. The organisms most frequently implicated as pathogens are H. influenzae, S. aureus, group A beta- hemolytic Streptococci, andF. pneumoniae. The risk of complication is great, with extension resulting in cavernous sinus thrombosis, meningitis, or brain abscess. Prompt hospitalization and parenteral antibiotic therapy are indicated
A 6-month-old infant is diagnosed with her first episode of otitis media. She does not have any allergies to medications. Which of the following medications would be the recommended initial therapy for this infant?
F. influenzae, S. pneumoniae, and Moraxella catarrhalis are the most common bacterial pathogens in otitis media of children. Amoxicillin is still the initial drug to use in uncomplicated otitis media because of its good coverage, except for beta-lactamase-positive organisms, and its excellent safety profile. The other drugs (except for erythromycin) are acceptable second-line medications
A5-year-old pedestrian is hit by a car in a mall parking lot and he is brought to the emergency department. There was loss of consciousness for less than 1 minute. On evaluation, the child has no neurologic deficits and a CT scan of the head reveals no intracranial abnormalities and no obvious skull fractures. The parents want to know what possible long-term problems there might be. You remember that problems after head trauma may include the development of seizures and that the risk of developing posttraumatic epilepsy is increased by which of the following?
Late posttraumatic epilepsy is diagnosed when a seizure occurs for the first time more than 1 week after a head injury. Factors that correlate with an increased risk of developing posttraumatic epilepsy include presence of a depressed skull fracture, acute intracranial hemorrhage, cerebral contusion, or unconsciousness lasting more than 24 hours. Because the risk of a subsequent seizure is approximately 75%, acute and chronic treatment with anticonvulsants is indicated. Loss of consciousness, retrograde amnesia, and vomiting are relatively common immediate consequences of head trauma. They are usually transient and are not highly correlated with a risk of subsequent posttraumatic seizures.
A 4-year-old previously healthy but unimmunized boy presents with sudden onset of high fever, inspiratory stridor, and refusal to drink. Of the following causes of inspiratory stridor, which best fits this clinical scenario?
Croup and epiglottitis have similar presentations but need to be distinguished immediately. Croup usually results from a viral infection of the larynx and epiglottitis from a bacterial (H. influenzae type B) infection of the epiglottis. Children with epiglottitis tend to be toxic in appearance. Croup involves the airway, and epiglottitis involves the airway and the digestive tract. Children with croup usually will swallow and drink.Children with epiglottitis most often will refuse to drink and may even drool as a result of their refusal to swallow saliva. Patients with foreign bodies in their upper airways do not typically have fever. Patients with vascular rings and laryngeal tumors have more gradual onset of symptoms.
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