Jeffrey P. Louie

Risk factors for cerebral edema in children with diabetic ketoacidosis

BACKGROUND Cerebral edema is an uncommon but devastating complication of diabetic ketoacidosis in children. Risk factors for this complication have not been clearly defined. METHODS In this multicenter study, we identified 61 children who had been hospitalized for diabetic ketoacidosis within a 15-year period and in whom cerebral edema had developed. Two additional groups of children with diabetic ketoacidosis but without cerebral edema were also identified: 181 randomly selected children and 174 children matched to those in the cerebral-edema group with respect to age at presentation, onset of diabetes (established vs. newly diagnosed disease), initial serum glucose concentration, and initial venous pH. Using logistic regression we compared the three groups with respect to demographic characteristics and biochemical variables at presentation and compared the matched groups with respect to therapeutic interventions and changes in biochemical values during treatment. RESULTS A comparison of the children in the cerebral-edema group with those in the random control group showed that cerebral edema was significantly associated with lower initial partial pressures of arterial carbon dioxide (relative risk of cerebral edema for each decrease of 7.8 mm Hg [representing 1 SD], 3.4; 95 percent confidence interval, 1.9 to 6.3; P<0.001) and higher initial serum urea nitrogen concentrations (relative risk of cerebral edema for each increase of 9 mg per deciliter [3.2 mmol per liter] [representing 1 SD], 1.7; 95 percent confidence interval, 1.2 to 2.5; P=0.003). A comparison of the children with cerebral edema with those in the matched control group also showed that cerebral edema was associated with lower partial pressures of arterial carbon dioxide and higher serum urea nitrogen concentrations. Of the therapeutic variables, only treatment with bicarbonate was associated with cerebral edema, after adjustment for other covariates (relative risk, 4.2; 95 percent confidence interval, 1.5 to 12.1; P=0.008). CONCLUSIONS Children with diabetic ketoacidosis who have low partial pressures of arterial carbon dioxide and high serum urea nitrogen concentrations at presentation and who are treated with bicarbonate are at increased risk for cerebral edema.

Androgen regulation of adrenocorticotropin and corticosterone secretion in the male rat following novelty and foot shock stressors

To examine mechanisms responsible for sex differences in hypothalamo-pituitary-adrenal (HPA) axis responsiveness to stress, we studied the role of androgens in the regulation of the adrenocorticotropin (ACTH) and corticosterone (CORT) responses to foot shock and novelty stressors in gonadectomized (GDX) or intact male F344 rats. Foot shock or exposure to a novel open field increased plasma ACTH and CORT, which was significantly greater in GDX vs. intacts. Testosterone (T) or dihydrotestosterone propionate (DHT) treatment of GDX animals returned poststress levels of ACTH and CORT to intact levels. Estrogen treatment of GDX males further increased poststress CORT secretion above GDX levels. There was no difference in the ACTH response of anterior pituitaries from intact, GDX, and GDX+DHT animals to CRF using an in vitro perifusion system. There were no differences in beta max or binding affinity of type I or II CORT receptors in the hypothalamus or hippocampus of intact, GDX, or GDX+DHT groups. These data demonstrate an effect of GDX on hormonal indices of stress. The increased response in GDX rats appears to be due to the release from androgen receptor mediated inhibition of the HPA axis. This inhibition by androgen is not due to changes in anterior pituitary sensitivity to CRH, nor to changes in type I or type II corticosteroid receptor concentrations.

Witnessed and unwitnessed esophageal foreign bodies in children.

Objective: The purpose of this study was to describe the clinical presentation of children with either an unwitnessed or witnessed esophageal foreign body. Methods: Retrospective chart review was performed. Patients were identified using ICD-9 code for esophageal foreign body. Clinical data and management techniques, along with complications were abstracted. Results: For the 5-year period of review, 255 patients were identified with an esophageal foreign body. 214 children had a witnessed ingestion. The mean age of the unwitnessed ingestion group was 2.3 years, compared to 4.6 years for a witnessed ingestion. In both groups, males and females were distributed equally and the most common ingested object was a coin. Bivariate, unadjusted analysis revealed that history of wheeze (OR, 4.35) and fever (OR, 11.15) had the largest association with patients who had an unwitnessed ingestion. Multivariate analysis indicated that any physical findings of wheeze, rhonchi, stridor, or retractions were associated significantly with a diagnosis of an unwitnessed foreign body. Children less than 2 years of age and with a documented fever are also predictive of an unwitnessed ingestion. Eleven children (4.3%) with esophageal abnormalities were also noted to have foreign bodies. Conclusions: Children who present to the emergency department two years old and younger, who have a documented fever and with respiratory findings should be considered at risk for having a retained esophageal foreign body. Children with esophageal abnormalities may also be at risk for retained esophageal foreign bodies.

Cecal volvulus in childhood

A neurologically impaired 7-year-old girl with type I lissencephaly presented to the emergency department with a 1-day history of fever and a firm abdomen. She had a bowel movement earlier in the day. The family denied a history of emesis, diarrhea, or bloody stool. Her past history was remarkable for intractable infantile spasms requiring multiple anticonvulsant medications and implantation of a vagal nerve stimulator. She also had chronic constipation, urinary retention, and recurrent urinary tract infections, requiring chronic antimicrobial prophylaxis. Previous upper gastrointestinal barium studies had shown normal anatomy without evidence of malrotation. Her medications were tiagabine, primidone, topiramate, nitrofurantoin, and lactulose. The child was pale and ill appearing. Her temperature was 39.0 C, heart rate 160 beats per minute, respiratory rate 24 breaths per minute, and blood pressure 117/73 mm Hg. Her skin was warm without exanthem or petechiae. Her distal pulses were strong. Abdominal examination showed a gastrostomy tube in place without surrounding erythema, edema, or discharge. Bowel sounds were diminished, and the abdomen was firm with diffuse tenderness and involuntary guarding. No umbilical or inguinal hernias were present. Rectal examination showed tenderness in the retrocecal region; the stool was guaiac-negative. Laboratory evaluation included a white blood cell count of 14,800 cells/mm3 with 20% lymphocytes, 75% segmented neutrophils, and 0% band forms. Hemoglobin, platelet count, serum transaminases, and electrolytes were normal. Blood and urine cultures were obtained and subsequently found to be sterile. An abdominal roentgenogram demonstrated a markedly distended loop of bowel within the lower abdomen and pelvis without evidence of free intraperitoneal air (Fig. 1). Barium enema revealed moderate distention of the hepatic flexure with beaking at its junction with the ascending colon, consistent with a cecal volvulus (Fig. 2). Laparotomy demonstrated a cecal volvulus with significant necrosis of the cecum and ascending colon. There was no evidence of true malrotation; the duodenum and left colon were in normal position. The volvulus was derotated, the nonviable segment of bowel (30 cm) resected, the distal lumen closed, and an endileostomy performed. The patient had an uneventful recovery and was discharged on the fifth postoperative day. 0749-5161/02/1804-0300 Vol. 18, No. 4 PEDIATRIC EMERGENCY CARE Printed in U.S.A. Copyright

Brain abscess following delayed endoscopic removal of an initially asymptomatic esophageal coin.

Brain abscesses are rare occurrences in pediatric patients, and making their diagnosis can be difficult. The two most commonly cited risk factors are otorhinologic infections and cyanotic congenital heart disease (CCHD). We present a 13-month-old child with a brain abscess who, 2 weeks prior, underwent rigid endoscopy for the extraction of a coin from the esophagus. We believe this to be the first such report of a brain abscess after rigid endoscopy for removal of an esophageal foreign body. In this case the esophageal coin was initially asymptomatic and had been present for weeks prior to removal. The potential association between delayed coin extraction and development of an intracranial infection, suggested by this report, may warrant investigation.

Interpretation of Cerebrospinal Fluid White Blood Cell Counts in Young Infants With a Traumatic Lumbar Puncture

Study objective We determine the optimal correction factor for cerebrospinal fluid WBC counts in infants with traumatic lumbar punctures. Methods We performed a secondary analysis of a retrospective cohort of infants aged 60 days or younger and with a traumatic lumbar puncture (cerebrospinal fluid RBC count ≥10,000 cells/mm3) at 20 participating centers. Cerebrospinal fluid pleocytosis was defined as a cerebrospinal fluid WBC count greater than or equal to 20 cells/mm3 for infants aged 28 days or younger and greater than or equal to 10 cells/mm3 for infants aged 29 to 60 days; bacterial meningitis was defined as growth of pathogenic bacteria from cerebrospinal fluid culture. Using linear regression, we derived a cerebrospinal fluid WBC correction factor and compared the uncorrected with the corrected cerebrospinal fluid WBC count for the detection of bacterial meningitis. Results Of the eligible 20,319 lumbar punctures, 2,880 (14%) were traumatic, and 33 of these patients (1.1%) had bacterial meningitis. The derived cerebrospinal fluid RBCs:WBCs ratio was 877:1 (95% confidence interval [CI] 805 to 961:1). Compared with the uncorrected cerebrospinal fluid WBC count, the corrected one had lower sensitivity for bacterial meningitis (88% uncorrected versus 67% corrected; difference 21%; 95% CI 10% to 37%) but resulted in fewer infants with cerebrospinal fluid pleocytosis (78% uncorrected versus 33% corrected; difference 45%; 95% CI 43% to 47%). Cerebrospinal fluid WBC count correction resulted in the misclassification of 7 additional infants with bacterial meningitis, who were misclassified as not having cerebrospinal fluid pleocytosis; only 1 of these infants was older than 28 days. Conclusion Correction of the cerebrospinal fluid WBC count substantially reduced the number of infants with cerebrospinal fluid pleocytosis while misclassifying only 1 infant with bacterial meningitis of those aged 29 to 60 days.

Are Serial Brain Imaging Scans Required for Children Who Have Suffered Acute Intracranial Injury Secondary to Blunt Head Trauma

In most instances, infants and children with moderate to severe head trauma undergo a head computed tomography (CT) scan as part of their initial evaluation. Several authors have advocated a routine second head CT after traumatic brain injury (TBI) to identify progressive lesions that may require surgical intervention. However, recent studies have challenged the need for a routine second brain imaging study after TBI. In addition, recent reports have raised concerns about the potential for malignancy following CT scanning, especially in pediatric patients. The authors performed a retrospective case series of all patients, aged 0 to 21 years, who presented to their 2 emergency departments (EDs) and received an International Classification of Disease—9th revision code related to intracranial injury. Out of 47 children, 5 (11%) underwent neurosurgical intervention following their second imaging study, and 1 of these interventions was unplanned after the first study. Compared with children who did not require an intervention following their second scan, children who received an intervention were more likely to have been subjected to nonaccidental trauma and to have presented to the ED more than 4 hours after the injury. Most children with intracranial injury following blunt trauma who did not require immediate neurosurgical intervention but instead underwent a follow-up brain imaging study did not require subsequent unplanned neurosurgical intervention. Serial brain imaging may not be required for all children with intracranial injury.

Herpes simplex virus infection in infants undergoing meningitis evaluation

In this study, HSV infection was identified in 0.42% of 26 533 encounters in 0 to 60-day-old infants being evaluated by LP for CNS infection. BACKGROUND: Although neonatal herpes simplex virus (HSV) is a potentially devastating infection requiring prompt evaluation and treatment, large-scale assessments of the frequency in potentially infected infants have not been performed. METHODS: We performed a retrospective cross-sectional study of infants ≤60 days old who had cerebrospinal fluid culture testing performed in 1 of 23 participating North American emergency departments. HSV infection was defined by a positive HSV polymerase chain reaction or viral culture. The primary outcome was the proportion of encounters in which HSV infection was identified. Secondary outcomes included frequency of central nervous system (CNS) and disseminated HSV, and HSV testing and treatment patterns. RESULTS: Of 26 533 eligible encounters, 112 infants had HSV identified (0.42%, 95% confidence interval [CI]: 0.35%–0.51%). Of these, 90 (80.4%) occurred in weeks 1 to 4, 10 (8.9%) in weeks 5 to 6, and 12 (10.7%) in weeks 7 to 9. The median age of HSV-infected infants was 14 days (interquartile range: 9–24 days). HSV infection was more common in 0 to 28-day-old infants compared with 29- to 60-day-old infants (odds ratio 3.9; 95% CI: 2.4–6.2). Sixty-eight (0.26%, 95% CI: 0.21%–0.33%) had CNS or disseminated HSV. The proportion of infants tested for HSV (35%; range 14%–72%) and to whom acyclovir was administered (23%; range 4%–53%) varied widely across sites. CONCLUSIONS: An HSV infection was uncommon in young infants evaluated for CNS infection, particularly in the second month of life. Evidence-based approaches to the evaluation for HSV in young infants are needed.

Impact of Enteroviral Polymerase Chain Reaction Testing on Length of Stay for Infants 60 Days Old or Younger

Objective To determine the impact of a cerebrospinal fluid enterovirus polymerase chain reaction (PCR) test performance on hospital length of stay (LOS) in a large multicenter cohort of infants undergoing evaluation for central nervous system infection. Study design We performed a planned secondary analysis of a retrospective cohort of hospitalized infants ≤60 days of age who had a cerebrospinal fluid culture obtained at 1 of 18 participating centers (2005–2013). After adjustment for patient age and study year as well as clustering by hospital center, we compared LOS for infants who had an enterovirus PCR test performed vs not performed and among those tested, for infants with a positive vs negative test result. Results Of 19 953 hospitalized infants, 4444 (22.3%) had an enterovirus PCR test performed and 945 (21.3% of tested infants) had positive test results. Hospital LOS was similar for infants who had an enterovirus PCR test performed compared with infants who did not (incident rate ratio 0.98 hours; 95% CI 0.89–1.06). However, infants PCR positive for enterovirus had a 38% shorter LOS than infants PCR negative for enterovirus (incident rate ratio 0.62 hours; 95% CI 0.57–0.68). No infant with a positive enterovirus PCR test had bacterial meningitis (0%; 95% CI 0–0.4). Conclusions Although enterovirus PCR testing was not associated with a reduction in LOS, infants with a positive enterovirus PCR test had a one‐third shorter LOS compared with infants with a negative enterovirus PCR test. Focused enterovirus PCR test use could increase the impact on LOS for infants undergoing cerebrospinal fluid evaluation.

Dental trauma in a pediatric emergency department referral center

Objective The purpose of this study was to describe dental and associated oral injuries in a pediatric population that presents to an emergency department. Methods We performed a retrospective study and identified children from January 2007 to September 2011. Charts were reviewed for any subject, age from newborn to younger than 19 years, based on International Classification of Diseases, Ninth Revision codes for any dental or oral injury. Data abstraction included demographics, time of day of presentation, location and identification of tooth (s) injured, management, and disposition. Results We identified 108 children with dental and if present, associated oral injuries. The median age was 12.3 years, the most common tooth injured were the primary (25.9%) or permanent (62%) upper central incisors, and the majority of subjects presented in the afternoon (mean time was 3:50 PM, SD ±24 minutes). A large proportion of dental injuries occurred in patients with permanent dentation (62%) and half of all children had more than 1 tooth injury. The majority of children (75%) were evaluated by either pediatric dental, oral surgery, or otolaryngology services, whereas 3.7% of the cases required multiple services. Twenty-five percent of children had an associated jaw fracture. Eighty-three percent of children were discharged home, of those, 49.1% were prescribed opioids, and 38.3% oral antibiotics. Conclusions Emergency departments are often relied upon to evaluate and treat simple and complex dental and oral injuries. The ability to use a multidisciplinary team to manage pediatric oral and dental trauma is essential for care.