An 8-month-old boy is brought to the emergency department due to fever and decreased appetite. For the past 3 days, he has had fever despite receiving acetaminophen and ibuprofen. Today, the patient has been refusing solid foods. He is still breastfeeding, but the mother notes that his latch feels weak and he falls asleep within 1-2 minutes of feeding. The patient has been awake only 2 hours today; most of that time, he was crying. Immunizations are up to date. He attends day care twice a week but has stayed home with his mother since becoming sick. Temperature is 40 C (104 F). Blood pressure, pulse, and respirations are normal for age. On examination, the patient appears sleepy and has a high-pitched cry when roused. The anterior fontanelle is bulging. The pupils are equal, round, and reactive to light. Extraocular movements are normal. There are no focal neurologic deficits. Complete blood count and blood culture are pending. Which of the following is the most appropriate next step in management of this patient?

Question

An 8-month-old boy is brought to the emergency department due to fever and decreased appetite.  For the past 3 days, he has had fever despite receiving acetaminophen and ibuprofen.  Today, the patient has been refusing solid foods.  He is still breastfeeding, but the mother notes that his latch feels weak and he falls asleep within 1-2 minutes of feeding.  The patient has been awake only 2 hours today; most of that time, he was crying.  Immunizations are up to date.  He attends day care twice a week but has stayed home with his mother since becoming sick.  Temperature is 40 C (104 F).  Blood pressure, pulse, and respirations are normal for age.  On examination, the patient appears sleepy and has a high-pitched cry when roused.  The anterior fontanelle is bulging.  The pupils are equal, round, and reactive to light.  Extraocular movements are normal.  There are no focal neurologic deficits.  Complete blood count and blood culture are pending.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d1b5_2879_bc81_69fab397c4b0_MD0003_00 This infant's irritability, fever, and bulging fontanelle are concerning for bacterial meningitis. Streptococcus pneumoniae and Neisseria meningitidis are the most common causes of bacterial meningitis in children age >1 month. In contrast to older children who typically have classic signs of increased intracranial pressure (eg, headache, vomiting, altered mental status), infants may have nonspecific fever, lethargy, poor feeding, and/or inconsolableness. A bulging fontanelle may be present on examination, but meningeal signs (eg, nuchal rigidity) are often absent. In hemodynamically stable infants, such as this patient, initial management includes obtaining blood and cerebrospinal fluid cultures (ie, lumbar puncture [LP]) to identify the pathogen, immediately followed by empiric intravenous antibiotics. LP is ideally performed prior to antibiotic administration because antibiotics can sterilize the CSF, making definitive diagnosis and use of narrow-spectrum, culture-based antibiotics challenging (Choice C). In addition, because the anterior fontanelle serves as a pop-off valve for reducing intracranial pressure, infants with open fontanelles are not at risk for herniation, so CT scan of the head is not required before LP (Choice A). Infants who are critically ill (eg, hypotension, status epilepticus) or who cannot immediately undergo LP should receive antibiotics first due to increased morbidity and mortality with delayed therapy. Third-generation cephalosporins (eg, ceftriaxone, cefotaxime) are effective against most strains of S pneumoniae and N meningitidis. Vancomycin is also administered due to the increasing prevalence of resistant S pneumoniae strains. (Choice B) In children, dexamethasone given before or with antibiotics can reduce the risk of sensorineural hearing loss in Haemophilus influenzae type b meningitis. In adults, dexamethasone also reduces morbidity and mortality in S pneumoniae meningitis. However, LP should be performed before administration of dexamethasone or antibiotics when possible. (Choice E) Mannitol is an osmotic diuretic used to decrease intracranial pressure in patients with impending brain herniation (often due to trauma). This patient is awake and stable with an open fontanelle, making brain herniation unlikely. Educational objective: Bacterial meningitis in infants can present nonspecifically with fever, lethargy, inconsolableness, and poor feeding. Physical examination may reveal a bulging fontanelle. In hemodynamically stable infants, lumbar puncture should be performed prior to antibiotic therapy to identify the pathogen and guide treatment. References: Pediatric bacterial meningitis: an update on early identification and management. (http://www.ncbi.nlm.nih.gov/pubmed/30358380)

An 8-Month-Old Boy Is Brought to the Emergency Department Due