Pediatrics
Certification Exam Review Online

Educational Objective:

List the common complications of bacterial meningitis.

Explanation:

Sensorineural hearing loss is the most common complication of bacterial meningitis. Such hearing loss may be due to direct cochlear infection or inflammation of the auditory nerve. All patients who have had bacterial meningitis should have hearing testing performed either prior or after hospital discharge. Other common sequelae include acute or chronic behavioral, visual, and neurologic (eg, seizure disorder) changes--all of which are not appreciated at the frequency of sensorineural hearing loss.

Reference:

Prober CG, et al. Central nervous system infections. In: Kliegman RM, et al, eds. Nelson Textbook of Pediatrics. 20th ed., 2015:2936-2948.

Primary amenorrhea describes a failure of the start of menstruation, whereas secondary amenorrhea describes the cessation of menstruation some time following menarche.

The first step in the workup of amenorrhea includes a measurement of urine chorionic gonadotropin to rule out pregnancy. Other possible causes of secondary amenorrhea include chronic diseases such as inflammatory bowel disease, hypothyroidism, cystic fibrosis, or polycystic ovary syndrome. Anorexia and the female athlete triad can also cause secondary amenorrhea.

Treatment depends on the cause of the amenorrhea and may include progestin therapy or oral contraceptives.

Reference:

Cromer B. Menstrual problems. In: Kliegman RM, et al, eds. Nelson Textbook of Pediatrics. 19th ed., 2011:685-691.

IVH is an intracranial hemorrhage involving premature infants. The risk is inversely proportional to gestational age and birthweight. This type of hemorrhage occurs in the gelatinous subependymal germinal matrix.

Many infants with IVH are asymptomatic. Symptoms in neonates with severe IVH may include hypotension, apnea, pallor, poor suck, high-pitched cry, seizures, and shock. Severity is graded by computed tomography (grades 1-4).

PVL occurs most often in premature infants with grade 4 IVH due to venous congestion. It consists of focal necrotic lesions in the periventricular white matter.

IVH and PVL are linked to impaired neurodevelopment and the development of hydrocephalus.

Reference:

Kliegman RM, et al, eds. Nelson Textbook of Pediatrics. 20th ed., 2016.

The most likely diagnosis is neonatal necrotizing enterocolitis, which is caused by mucosal or transmural necrosis of the intestine. When necrosis develops in the intestine, gas accumulates in the bowel wall, called pneumatosis intestinalis, and necrosis progresses to perforation and sepsis. Abdominal radiography with a finding of pneumatosis intestinalis is diagnostic.

The incidence and severity of necrotizing enterocolitis is inversely proportional to gestational age and birthweight. Risk factors include prematurity and the start of enteral feedings.

Symptoms include many nonspecific signs such as lethargy, temperature instability, and abdominal distension. Other signs include hypoglycemia and acidosis. Bloody stools occur 25% of the time. The illness spectrum may be mild or severe, and its progression may be rapid.

Treatment includes antibiotics, a nasogastric tube, and intravenous fluids instead of enteral feedings, as well as surgery, if indicated, for perforation.

Reference:

Kliegman RM, et al, eds. Nelson Textbook of Pediatrics. 20th ed., 2016.

Drowning is defined as a process resulting in primary respiratory impairment from submersion/immersion in a liquid medium. Confusing and inconsistent terms, such as "near-drowning," "secondary drowning," "passive drowning," "silent drowning," "wet drowning," and "dry drowning" are outdated and should be discouraged. The term "drowning" should be used regardless of the narrative associated with the drowning. Outcome is captured by adding an adjective (eg, fatal, non-fatal) to the word "drowning."

Within the pediatric population, rates of drowning peak during in both the toddler and adolescent years. Age influences the circumstances of drowning. Among younger children, drowning usually occurs within the home, often during brief lapses of adult supervision. Infants drown in bathtubs most frequently, either when they are left unattended or as the result of abusive injury. Toddlers typically drown in swimming pools.

Although most drowning events occur in previously healthy children, certain pre-existing medical conditions may play a role. Children who have seizure disorders have a four-fold increased risk of drowning when compared with the general population.

The physiologic consequences of drowning are due primarily to hypoxic-ischemic and reperfusion injuries. The devastating long-term neurologic consequences of drowning occur almost exclusively among patients who have drowning-associated asphyxial cardiac arrests. Patients who do not experience cardiac arrest will rarely have significant sequelae. Drowning-associated asphyxia is caused by laryngospasm, apnea, or pulmonary aspiration of water. The resultant hypoxia, hypercapnia, and acidosis can decrease myocardial contractility, elevate pulmonary artery and systemic vascular resistance, and produce cardiac arrhythmias (eg, bradycardia, asystole, ventricular fibrillation). With a sufficient duration of submersion, the asphyxial insult inevitably results in cardiac arrest.

The degree of central nervous system injury is related to the duration of untreated cardiac arrest, the effectiveness of initial cardiopulmonary resuscitation, and secondary cerebral injuries after resuscitation (eg, further hypoxic episodes, inadequate cerebral blood flow, cerebral edema, hyperthermia).

The initial neurologic examination on presentation often is of limited use in predicting outcome. Children who are comatose or severely impaired require serial examinations over the following 24 hours to clarify the prognosis. Those who survive and have a good outcome generally demonstrate spontaneous, purposeful movement and normal brainstem function in the first 24 hours.

Measures specifically directed to limiting neurologic injury in the postresuscitation phase have not yet demonstrated benefits for drowning persons. Immediate resuscitation and therapeutic hypothermia are the only measures shown to reduce brain damage in the setting of hypoxic-ischemic injury. Optimal supportive care, with attention to adequate oxygen delivery and prompt treatment of seizures, is important to avoid secondary hypoxic-ischemic damage. Hypoglycemia can have detrimental neurologic effects and should be avoided (and treated promptly when it does occur). Hyperglycemia also is associated with worse neurologic outcomes, but it is not clear whether treatment of hyperglycemia improves these outcomes.

References:

Meyer RJ, Theodorou AA, Berg RA. Childhood drowning. Pediatr Rev. 2006;27(5):163-168.

Quan L. Near-drowning. Pediatr Rev. 1999;20(8):255-259.