Extreme leukocytosis in patients presenting to a pediatric emergency department.

We determined the frequency and clinical significance of white blood cell (WBC) counts greater than or equal to 25,000/microliters in children presenting to an emergency department (ED) and defined a degree of leukocytosis which might be considered extreme in this setting. Records of all patients seen in the ED between February 1985 and December 1986 with WBC counts greater than or equal to 25,000/microliters were identified. Each patient was paired with the chronologically nearest patient with a WBC count between 15,000 and 25,000/microliters. Of the total WBCs obtained, 5.8% were greater than or equal to 25,000/microliters; only 1% were greater than or equal to 35,000/microliters. Eighteen percent of patients with counts greater than or equal to 25,000/microliters had a serious disease, and 6% had bacteremia. Twenty-six percent of patients with counts greater than or equal to 35,000/microliters had a serious disease, and 10% had bacteremia. On the basis of infrequency and severity of illness, we suggest that, in children presenting to a pediatric emergency department, WBC counts greater than or equal to 35,000/microliters be considered extreme leukocytosis.

Effects of causative organism and presence or absence of meningitis on white blood cell counts in children with bacteremia.

The records of 182 children with bacteremia due to Streptococcus pneumoniae, Haemophilus influenzae type b, or Neisseria meningitidis were reviewed to determine which variables other than the presence or absence of bacteremia might affect patients' white blood cell (WBC) counts. There were no significant or consistent effects of age, sex, race, or duration of illness on WBC counts. Significantly lower mean WBC counts were noted for patients with, versus those without, meningitis and patients with H influenzae type b bacteremia versus those with S pneumoniae bacteremia. As a screening test for bacteremia, the WBC count is less useful in children with either meningitis or infection caused by H influenzae type b than in children with nonmeningeal infections caused by S pneumoniae.

Bacteremia in children afebrile at presentation to an emergency room.

Charts of 182 outpatient children with bacteremia caused by Streptococcus pneumoniae, Haemophilus influenza type b or Neisseria meningitidis were reviewed. Twenty-four patients (13%) were afebrile (temperature less than 37.8 degrees C) at presentation. Five afebrile patients had no history of fever. Four of the five had localizing signs of infection and one appeared toxic. Afebrile patients were not strikingly different from febrile bacteremic patients by any assessments. Bacteremia in children cannot be excluded on the basis of absence of fever by history and examination. Blood cultures should be performed on afebrile children who either have localizing signs of serious bacterial infection or appear toxic.

Similarity in white blood cell counts between white and black children with bacteremia.

The charts of 104 white and 52 black children with bacteremia caused by Streptococcus pneumoniae or Haemophilus influenzae type b were reviewed to determine each patient's white blood cell (WBC) and absolute polymorphonuclear cell (PMN) counts at the time of presentation to the emergency room. Mean WBC and PMN counts were virtually identical for the racial groups, 18,300 vs. 18,700/microliter and 12,900 vs. 13,000/microliter, respectively. Examination of subgroups of white and black children with or without meningitis or other focal infection also revealed no significant differences between races, although significantly lower mean WBC and PMN counts were found in children with, compared to those without, meningitis regardless of race. As an aid to the identification of children at high risk for S. pneumoniae or H. influenzae type b bacteremia, it appears that WBC and PMN counts may be interpreted without regard to race.

Fever without localizing signs in children. Detection and management of occult bacteremia.

Occult bacteremia should be of major concern in the child with fever without localizing signs. A number of clinical features and laboratory findings correlate with the risk of bacteremia in such children, and their recognition permits the identification of a group of children at high risk. Treatment of such children with antibiotics on an ambulatory basis appears to significantly lessen the incidence of persistent bacteremia, subsequent meningitis, and other serious localized bacterial infections.

Composition of nasal secretion in patients with cystic fibrosis.

Quantitative examination of nasal secretion in patients with cystic fibrosis revealed a significantly greater than normal concentration of calcium, a finding in keeping with the hypothesized importance of this ion in the pathophysiology of the disease.