Microbiology of acute and chronic sinusitis in children and adults

The microbiology of infections of the paranasal sinuses can be anticipated according to the patient's age, clinical presentation, and immunocompetence. In acute sinus disease, viral upper respiratory infections frequently precede bacterial superinfection by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Staphylococci and respiratory anaerobes are common in chronic sinus infection, which may also be caused by exacerbations of infection with the bacterial species that cause acute disease. Enterobacteriaceae may be found in patients with nosocomial sinusitis who are predisposed to the development of sinusitis by prolonged nasogastric and nasotracheal intubation. Immunosuppressed patients have episodes of sinusitis caused by the usual agents associated with acute sinusitis in immunocompetent patients, and they may also become infected with a broad array of unusual agents, including mycobacterial species, fungi, and protozoa.

Acute otitis media in children with bronchiolitis

OBJECTIVE

We investigated the prevalence and the etiology of acute otitis media (AOM) in children with bronchiolitis to determine whether AOM in such children is due entirely or mainly to respiratory syncytial virus (RSV), in which case routine antimicrobial treatment would not be appropriate.

METHODS

The study group consisted of children aged 2 to 24 months with bronchiolitis. In patients with AOM at entry, nasal washings for RSV enzyme-linked immunosorbent assay were obtained, and Gram-stained smear, bacterial culture, and reverse transcriptase polymerase chain reaction to detect the presence of RSV were performed on middle-ear aspirates. Patients without AOM were reevaluated at 48 to 72 hours, 8 to 10 days, and 18 to 22 days.

RESULTS

Forty-two children with bronchiolitis were enrolled. Sixty-two percent had AOM at entry or developed AOM within 10 days. An additional 24% had or eventually developed otitis media with effusion. Only 14% remained free of both AOM and otitis media with effusion throughout the 3-week observation period. All patients with AOM had 1 or more bacterial pathogens isolated from one or both middle-ear aspirates. Of 33 middle-ear aspirates, Streptococcus pneumoniae was isolated in 15, Haemophilus influenzae in 8, Moraxella catarrhalis in 8, and Staphylococcus aureus in 2. Two middle-ear aspirates yielded 2 pathogens each; 2 aspirates had no growth. RSV was identified in 17 (71%) of 24 patients with AOM.

CONCLUSION

Bacterial AOM is a complication in most children with bronchiolitis. Accordingly, in patients with bronchiolitis and associated AOM, antimicrobial treatment is indicated.

A streptococcal score card revisited

OBJECTIVE

To evaluate the utility of a simple scoring system as a predictor of obtaining a positive throat culture for group A streptococci (GAS).

DESIGN

Prospective descriptive study. Scores were assigned prior to the availability of the results of throat cultures.

SETTING

Emergency department and walk-in clinic of the Children's Hospital of Pittsburgh.

PATIENTS

Patients were 365 children between the ages of two and 16 years with acute onset of sore throat and a history of or documentation of fever within the preceding 24 hours.

INTERVENTIONS

A streptococcal score was assigned on the basis of a 6-point schema in which the features were 1) age; 2) season; 3) temperature of at least 38.3 degrees C; 4) adenopathy; 5) pharyngeal erythema, edema, or exudate; and 6) no symptoms of a viral upper respiratory infection (conjunctivitis, rhinorrhea, or cough). A throat culture was performed for the isolation of GAS.

MAIN OUTCOME MEASURE

Positive predictive value of the streptococcal score in identifying children with a positive throat culture for GAS.

RESULTS

A score of 5 or 6 predicted a positive culture for GAS in 59 and 75% of children, respectively. In patients with evidence of acute pharyngitis, the combination of age between five and 15 years, fever and absence of upper respiratory symptoms predicted a positive culture for GAS in 72% of patients.

CONCLUSIONS

The score can be used to predict the likelihood that a throat culture will be positive for GAS.

Field inversion gel electrophoresis as a typing system for group A streptococcus

Field inversion gel electrophoresis (FIGE) was performed on 139 isolates of group A streptococcus (GAS) representing 72 different M types. Multiple isolates were tested for 27 M types (range, 2-19). Each of the M types tested had at least one unique banding pattern that was not observed in any other M type. For 23 of 27 M types for which multiple isolates were available, band profiles of the isolates were the same or differed by < 3 bands and are considered indistinguishable or closely related. These data demonstrate that FIGE of the DNA of GAS identifies differences between and within M types.

Management of rhinosinusitis in children: consensus meeting, Brussels, Belgium, September 13, 1996

OBJECTIVES

To (1) provide definitions for the different forms of pediatric rhinosinusitis, with an enumeration of the main symptoms and signs; (2) provide indications for microbiological, allergic, and immunologic assessment as well as for imaging studies; (3) suggest standard medical management with judicious use of antimicrobial agents; and (4) discuss indications for surgery.

DATA SOURCES

Clinical studies and literature data relevant to the different topics of pediatric rhinosinusitis.

CONCLUSIONS

Rhinosinusitis in children is a multifactorial disease in which the importance of several predisposing factors changes with increasing age. Continued study to obtain a better understanding of the disease and carefully controlled comparative evaluations of medical and surgical therapies are suggested.

Efficacy of thermal treatment and copper-silver ionization for controlling Legionella pneumophila in high-volume hot water plumbing systems in hospitals

BACKGROUND

Thermal treatment and copper-silver ionization are often used for controlling Legionella pneumophila in high-volume hospital plumbing systems, although the comparative efficacies of these measures in high-volume systems are unknown.

METHODS

Thermal treatment of a hot water circuit was accomplished by flushing hot water (> 60 degrees C) through distal fixtures for 10 minutes. Copper-silver ionization was conducted in three circuits by installing units into return lines immediately upstream from hot water tanks. Recovery rates of L. pneumophila were monitored by culturing swab samples from faucets. Concentrations of copper and silver in water samples were determined by atomic absorption spectrophotometry.

RESULTS

Four heat-flush treatments failed to provide long-term control of L. pneumophila. In contrast, ionization treatment reduced the rate of recovery of L. pneumophila from 108 faucets from 72% to 2% within 1 month and maintained effective control for at least 22 months. Only three samples (1.9%) of hot water from faucets exceeded Environmental Protection Agency standards for silver, and none exceeded the standards for copper. Of 24 samples obtained from hot water tanks, 42% and 50% exceeded the silver and copper standards, respectively.

CONCLUSIONS

Copper-silver ionization effectively controls L. pneumophila in high-volume plumbing systems and is superior to thermal treatment; however, high concentrations of copper and silver can accumulate at the bottom of hot water tanks.

Airway complications in patients with infection caused by HIV

Numerous problems may be identified in the airways of patients with HIV infection. In many cases, these airway conditions represent exaggerations of infections seen in the immunocompetent host. However, in other instances, they represent manifestations of unique problems, infectious and/or neoplastic, that are a consequence of the profound immunosuppression seen in the patient with infection due to HIV.

Infective endocarditis: 35 years of experience at a children's hospital

We review the predisposing conditions, the presenting signs and symptoms, as well as the risk factors and bacterial etiologies in children with infective endocarditis, focusing on hospital course and outcome. We conducted a retrospective analysis of 76 cases of endocarditis in 73 patients occurring at Children's Hospital of Pittsburgh from January 1958 through December 1992. The median age of the patients was 9 years (range, 1 month to 18 years). Predisposing conditions included congenital heart disease (62 patients) and rheumatic heart disease (four patients). Seventy-seven percent of the children with congenital heart disease had undergone cardiac surgery. After therapy with appropriate antibiotics was started, blood cultures for 67 patients (70 episodes of infective endocarditis) remained positive for a mean (+/-SD) of 0.7 +/- 1.41 days, and all patients who presented with fever (75 episodes in 72 patients) remained febrile for a mean (+/-SD) of 4.28 +/- 6.21 days. Secondary fever occurred in 39% of the children. Thirty (41%) of the 73 patients survived without any complications and 13 (18%) died. Fifteen children with complications required surgery. Children with endocarditis caused by Staphylococcus aureus were more likely than those with infection caused by viridans streptococci to have prolonged fever, secondary fever, and/or complications as well to require surgery.

Development and multicenter evaluation of Multistation Clinical Teaching Scenarios on immunization: the ATPM-CDC Teaching Immunization for Medical Education (TIME) Project

INTRODUCTION

The objective of this project was to develop and evaluate case-based immunization education materials that use a new teaching method called Multistation Clinical Teaching Scenarios (MCTS) for use in medical school clerkships and primary care residencies.

METHODS

A multidisciplinary team developed objectives, abstracted clinical cases, and created MCTS modules, which use contextual learning, problem solving, and small-group interaction.

RESULTS

Mean scores increased from the 10-item pretest to the posttest by 3.2 (95% confidence interval [CI] of 2.8 to 3.6) items for measles, 3.8 (CI = 3.4 to 4.1) for influenza, and 1.8 (CI = 1.4 to 2.1) for hepatitis B (P < .01 for each). To evaluate the materials, we administered questionnaires and conducted focus groups. Most (99%) of the students and residents rated the materials highly, as did most (89%) facilitators.

CONCLUSIONS

This new method has been widely tested, increases content mastery, and is well received.

Conjunctivitis in infants and children

BACKGROUND

Acute bacterial conjunctivitis, chiefly affecting young children, is generally caused by one of three common pathogens, Haemophilus influenzae, Streptococcus pneumoniae and adenovirus. H. influenzae is the most prevalent causative organism. Some patients presenting initially with conjunctivitis subsequently develop acute otitis media, with H. influenzae the most common etiologic agent of what has been termed the "conjunctivitis-otitis" syndrome. Optimal treatment of acute conjunctivitis would result in a clinical and bacteriologic cure of the conjunctivitis and the prevention of the development of otitis media. Application of topical antimicrobials at 4- to 6-h intervals a day for 1 week to 10 days results in the resolution of the conjunctivitis. However, topical treatment is difficult to administer to toddlers and does not effectively reduce the potential for the development of otitis media. Compared with topical and placebo treatment, oral antibiotics effective against H. influenzae have proved to be most effective in preventing the otitis media associated with conjunctivitis.

CONCLUSION

Acute bacterial conjunctivitis is a common disorder in children < 6 years of age. H. influenzae is the most common etiology of the "conjunctivitis-otitis syndrome." The optimal treatment for this condition is still being studied.

Urinary tract infections in young febrile children

UTI is a common and important clinical problem in infants and young children, with a prevalence of 5.3% among febrile infants seen in our Emergency Department. White females with rectal temperature > or = 39 degrees C are at particularly high risk (prevalence, 17%). Several studies have highlighted the limitations of the standard urinalysis for identifying UTI in infants and young children and have recommended performance of both urinalysis and urine culture. Alternative methods such as dipstick urinalysis, although attractive because of ease of performance, are inadequate as a screen for UTI. Hemocytometer WBC counts of an uncentrifuged urine specimen can be performed in an office or hospital-based laboratory with minimal training. Performance of Gram-stained smears, however, is most appropriate for the hospital-based laboratory. In the hospital setting where both tests can readily be performed, the positive predictive value of the combination of pyuria and bacteriuria (85%) allows prompt institution of antimicrobial therapy before culture results are available, whereas the lower positive predictive value of the single finding of either pyuria or bacteriuria (40%) justifies delaying treatment decisions until culture results are available. In the office setting where hemocytometer counts can easily be performed, culturing only specimens with pyuria and those of children presumptively treated with antimicrobials will result in the identification of almost all patients with true UTI, sparing large health care expenditures. Although the urine culture is traditionally regarded as the gold standard of UTI, positive urine cultures may occur secondary to contamination or in cases of ABU, leading to a false diagnosis of UTI. In contrast we found pyuria to be a reliable marker to discriminate infection from colonization of the urinary tract. The sustained absence of an inflammatory response, on repeat UA within 24 h, constitutes strong evidence that infection is absent. Management of ABU is controversial; many experts recommend withholding antibiotics because eradication of low virulence organisms may be followed by colonization with more virulent species that cause pyelonephritis. Preliminary results of our ongoing treatment trial suggest that management of young febrile children with UTI as outpatients receiving oral cefixime is as efficacious as inpatient management with intravenous cefotaxime. Results of renal ultrasound and DMSA scan at the time of infection have not modified management in any patient. Accordingly selective rather than routine performance of ultrasound is recommended. A voiding cystourethrogram at 1 month and a DMSA scan 6 months later have been valuable in identifying patients with vesicoureteral reflux and renal scarring, respectively. Among patients initially identified as having acute pyelonephritis, the incidence of renal scarring at 6 months has been substantially more frequent (approximately 40%) than we had expected. However, the long term implications of small scars identified with renal scintigraphy remain to be determined.

Pertussis, pertussis vaccine, and care of exposed persons

BACKGROUND

Pertussis is a highly contagious bacterial infection caused by Bordetella pertussis. Before routine vaccination against pertussis was available, most persons were infected during childhood. After widespread vaccination, however, the incidence of pertussis in the United States dropped by more than 95 percent, though localized outbreaks continue to occur.

METHODS

A multidisciplinary team developed a set of review articles as part of continuing medical education modules in the Teaching Immunization in Medical Education (TIME) Project. The team developed the materials using expert judgment and selected materials from the literature and the Centers for Disease Control and Prevention (CDC). The first step was the creation of specific learning objectives that used the spectrum of Bloom's taxonomy, when possible. After the materials were developed, they were pilot-tested and revised. Subsequently they underwent summative evaluation by field-testing the materials with 24 other primary care physicians. Then the materials were reviewed by the CDC and national vaccine experts and revised based on their comments.

RESULTS AND CONCLUSIONS

The efficacy of whole-cell pertussis vaccine is about 70 to 90 percent, though local adverse events are common. Since 1990 several purified, acellular pertussis vaccines have been developed that have one quarter to one half of the common adverse events associated with whole-cell vaccine and have similar efficacy rates. The incidence of pertussis can be further reduced by increasing age-appropriate vaccination rates.

Emerging resistance to antibiotics: impact on respiratory infections in the outpatient setting

OBJECTIVE

To review the major mechanisms of antibiotic resistance and provide an overview of currently available oral antibiotics. This article discusses the impact of antibiotic resistance on respiratory infections (eg, otitis media, sinusitis, and pneumonia) encountered in the outpatient setting and appropriate management strategies for these infections are proposed.

DATA SOURCES

A Medline search was performed to identify recent references from the English language pertinent to this topic. Proposed management schemes for infections due to antibiotic-resistant bacteria were derived from current literature as well as the opinion of the authors.

RESULTS

Currently available oral antibiotics including penicillins, cephalosporins, macrolides, trimethroprim/sulfamethoxazole, and clindamycin continue to provide effective therapeutic options despite the increasing importance of antibiotic resistance in bacteria causing respiratory tract infections in the outpatient setting. The effectiveness of a given agent may no longer be assured, leading to the need for development of updated management strategies for patients experiencing treatment failure with antibiotics. Diagnostic strategies (ie, tympanocentesis) and novel treatment algorithms (eg, use of amoxicillin in combination with amoxicillin/clavulanate) for patients experiencing clinical failures potentially due to antibiotic-resistant bacteria are proposed.

CONCLUSIONS

The increasing prevalence of antibiotic resistant bacteria (especially penicillin-resistant Streptococcus pneumoniae) is leading to new approaches to the management of common respiratory infections in the outpatient setting. Additional experience and careful clinical trials are necessary to identify optimal management strategies for these infections.

Unusual case of inflammatory spinal epidural mass (Castleman syndrome)

Castleman syndrome (giant lymph node hyperplasia) is a rare, heterogeneous lymphoproliferative disorder of unknown etiology and pathogenesis. Most cases occur as mediastinal masses, although extrathoracic involvement including nodal and extranodal locations have been reported. The localized variants (solitary lesions) respond well to surgical excision. We report a 10-year-old boy who presented with headache, intermittent fever, and progressive weakness of his legs. MRI imaging showed an enhancing epidural mass with impingement on the spinal cord at the C6-T2 level. Other laboratory abnormalities included anemia, hypergammaglobulinemia, increased erythrocyte sedimentation rate, and cerebrospinal fluid pleocytosis with slightly increased cerebrospinal protein. The mass was partially resected and the histopathology showed lymphoplasmocytic infiltration compatible with Castleman syndrome. There was no evidence of malignancy. Castleman syndrome is the most likely diagnosis in the presence of the associated systemic findings, although the epidural site for lymphoplasmocytic inflammation is atypical.

Is urine culture necessary to rule out urinary tract infection in young febrile children?

OBJECTIVE

To determine whether the absence of pyuria on the enhanced urinalysis can be used to eliminate the diagnosis of urinary tract infection, avoiding the need for urine culture and sparing large health care expenditures.

DESIGN

Results of an enhanced urinalysis (hemocytometer counts and interpretation of Gram-stained smears) performed on uncentrifuged urine specimens obtained by catheter were correlated with urine cultures in young febrile children at the Children's Hospital of Pittsburgh Emergency Department. In a group of 4253 children (95% febrile) less than 2 years of age, pyuria was defined as > or = 10 white blood cells/mm3, bacteriuria as any bacteria on any of 10 oil immersion fields in a Gram-stained smear and a positive culture as > or = 50,000 colony-forming units/ml. A subgroup of 153 children with their first diagnosed urinary tract infection were enrolled in a separate treatment trial, acute phase reactants (peripheral white blood cell count, erythrocyte sedimentation rate and C-reactive protein) were obtained and 99Tc-dimercaptosuccinic acid renal scans were performed.

RESULTS

The presence of either pyuria or bacteriuria and the presence of both pyuria and bacteriuria have the highest sensitivity (95%) and positive predictive value (85%), respectively, for identifying positive urine cultures. Because a white blood cell count in a hemocytometer is the technically simpler component of the enhanced urinalysis, we chose to analyze the false negative results and achievable cost savings of using pyuria alone as the sole criterion for omitting urine cultures. If in this study urine cultures had been performed only on specimens from children who had pyuria or were managed presumptively with antibiotics, cultures of 2600 (61%) specimens would have been avoided. Twenty-two of 212 patients with positive urine cultures would not have been identified initially. However, based on interpretation of acute phase reactants, initial 99Tc-dimercaptosuccinic acid scan results, response to management and incidence of renal scarring 6 months later, 14 of the 22 patients most likely had asymptomatic bacteriuria and fever from another cause. The remaining 8 patients probably had early urinary tract infection.

CONCLUSIONS

The analysis of urine samples obtained by catheter for the presence of significant pyuria (> or = 10 white blood cells/mm3) can be used to guide decisions regarding the need for urine culture in young febrile children.

Otitis media and sinusitis: similar diseases

Otitis media and sinusitis are common pediatric diagnoses and share common features that are described in this article. Although the anatomy, physiology, and disease processes are not identical, knowledge of the basic pathophysiology of middle ear disease often enables a clinician to have a useful working understanding of sinus disease. Recognizing these similarities provides a better understanding of their pathophysiology and treatment.

Field inversion gel electrophoretic analysis of Legionella pneumophila strains associated with nosocomial legionellosis in children

Two nosocomial cases of Legionnaires' disease occurred in children. Legionella pneumophila serogroup 1 was isolated from both patients and 30 of 39 plumbing system sites in the hospital. The patient and hospital environmental isolates yielded identical field inversion gel electrophoretic patterns which differed from patterns observed with epidemiologically unrelated strains.

Comparison of M and T type antigen testing to field inversion gel electrophoresis in the differentiation of strains of group A streptococcus

Recent clusters of patients with acute rheumatic fever and invasive group A Streptococcus (GAS) have stimulated renewed interest in the epidemiology of streptococcal infections. We compared conventional serotyping for M and T antigens and serum opacity factor with field inversion gel electrophoresis (FIGE) for distinguishing among GAS. Fifteen pairs of throat isolates obtained from children positive for GAS before and after therapy were evaluated by conventional serotyping and by FIGE after SmaI digestion. Ten of the 15 pairs were identical by serotyping. FIGE correctly identified the 10 concordant and 5 discordant pairs. Individual clones were identified within each M type tested, including analysis performed on additional isolates of M1 and M3 obtained from the Centers for Disease Control and Prevention. This preliminary experience suggests that FIGE can successfully determine whether serial isolates from a given patient represent persistence of one strain or acquisition of a new strain of GAS and that this method might provide an alternative typing system for GAS.

Identification of cases of acute rheumatic fever managed on an outpatient basis

The incidence of acute rheumatic fever has varied over the past several decades. The usual source of case ascertainment has been medical record discharge diagnosis coding. By reviewing both the Children's Hospital of Pittsburgh medical records discharge data and the Division of Cardiology computer database for the years 1982 to 1993, 173 cases of acute rheumatic fever were identified including 63 patients who were managed exclusively as outpatients. Seventy-three percent of patients diagnosed before 1990 were managed as inpatients, compared with 48% of patients diagnosed 1990 and later. The incidence of acute rheumatic fever may be underestimated if patients managed without hospitalization are not identified.

Epiglottitis and Haemophilus influenzae immunization: the Pittsburgh experience--a five-year review

OBJECTIVE

Current trends in the clinical presentation and management of children with epiglottitis at Children's Hospital of Pittsburgh were reviewed for the years 1988 to 1993.

METHODOLOGY

The medical records of all patients diagnosed as having epiglottitis between July 1988 and June 1993 at the Children's Hospital of Pittsburgh were reviewed. An additional telephone survey was conducted among the primary care physicians of those patients to collect information regarding administration of Haemophilus influenzae type b (HIB) vaccines.

RESULTS

During the study period 28 children (age range, 11 months to 11 years, 10 months) were admitted with the diagnosis of epiglottitis. Cases declined remarkably in 1991. Fever, sore throat, and stridor were the usual symptoms. HIB was the most common cause of epiglottitis accounting for 21 cases. Candida albicans was recovered from the surface culture of the epiglottis in two patients. At least 11 children experienced vaccine failure: nine with polysaccharide vaccine and two with the conjugate vaccine for HIB.

CONCLUSION

Cases of epiglottitis have declined dramatically since licensure of HIB conjugate vaccines for use in early infancy. At least 52% of the reported cases represent vaccine failures with the purified polysaccharide vaccine.

Progressive varicella presenting with pain and minimal skin involvement in children with acute lymphoblastic leukemia

PURPOSE

Here we report the experience at the Children's Hospital of Pittsburgh (CHP) with varicella zoster virus (VZV) in children with acute lymphoblastic leukemia (ALL). This record review was prompted by a patient with ALL who died suddenly of varicella hepatitis within 24 hours of presentation with a single skin lesion.

METHODS

We reviewed the medical records of children diagnosed with ALL at the CHP from January 1984 through December 1993, who subsequently developed VZV infection.

RESULTS

Of 294 patients aged 0 to 15 years, 41 (14%) were identified as having had 42 episodes of VZV infection. Twenty patients (49%) had received prophylaxis with varicella zoster immunoglobulin (VZIG), and all 39 patients in whom the diagnosis was made premortem were treated with acyclovir. Twenty-nine of the 42 cases (70%) had disease limited to the skin. Thirteen cases (30%) had extracutaneous involvement, and five of these episodes (12% of all cases) ended in death. Risk factors for progressive varicella included age greater than 6 years and intensive immunosuppressive therapy at the time of exposure. Six of eight patients with progressive varicella, including two who died, had received VZIG. The clinical presentation in 10 of 13 patients with progressive disease and in four of five patients who died was dominated by severe abdominal and/or back pain. In seven cases, these symptoms preceded the development of skin lesions by several days, and in six patients were associated with extensive involvement of the spleen by varicella, as demonstrated histopathologically by the presence of Howell-Jolly bodies on peripheral-blood smear or radiographically. No patient with uncomplicated varicella was reported to have had premonitory pain.

CONCLUSION

Recognition of these prodromes and suspicion of varicella even in the absence of skin lesions and even in children with a history of prior disease or VZIG administration should prompt early diagnostic and therapeutic measures.

Parainfluenza and influenza virus infections in pediatric organ transplant recipients

We retrospectively reviewed parainfluenza and influenza virus infections that occurred in pediatric organ transplant recipients at our hospital from January 1985 through September of 1992. Cultures of respiratory specimens revealed 45 infections in 42 transplant recipients (32 cases of parainfluenza and 13 cases of influenza virus infection). The following organs were transplanted: liver (28 patients), small bowel with and without liver (4), heart (3), lung with and without heart (5), and kidney (2). Clinical presentations of the patients and outcomes were similar regardless of the type of virus isolated or the type of organ transplanted. There were 20 cases in which patients had upper respiratory symptoms but did not require supplemental oxygen, nine cases in which patients required oxygen supplementation only, and eight cases in which the patients survived with mechanical ventilation. Eight patients died (five had parainfluenza, three had influenza virus infection); four children had serious concurrent infections (cytomegaloviral pneumonia in one patient, bacteremia in two, bacteremia and pneumonia in one). Factors associated with poor outcome for the entire group were age (increased morbidity and mortality if < 6 months old), augmentation of immunosuppression, and onset of infection within 1 month of transplantation. In this patient population, parainfluenza and influenza infections were important causes of morbidity and mortality.

Dexamethasone therapy for children with bacterial meningitis. Meningitis Study Group

OBJECTIVE

To determine whether treatment with dexamethasone and ceftriaxone for children with bacterial meningitis reduces the frequency of either sensorineural hearing loss or other neurologic sequelae.

DESIGN

This was a prospective, multicentered, placebo-controlled clinical trial. Subjects were followed for 1 year.

SETTING

The study was conducted in six children's hospitals located in Pittsburgh, Houston, Los Angeles, Chicago, Washington, D.C., and Columbus, Ohio.

PATIENTS

Enrolled were 173 children, 8 weeks to 12 years of age, with suspected bacterial meningitis; 143 children were evaluable. Eighty-seven percent of patients were followed for at least 6 weeks to 3 months, and 67% were followed for 1 year.

INTERVENTIONS

Subjects were randomized to receive ceftriaxone with or without dexamethasone (0.15 mg/kg every 6 hours for 4 days). Auditory brainstem responses (ABR) were measured within 24 hours of admission.

MAIN OUTCOME MEASURES

Hearing, development, and neurologic sequelae were assessed at the time of discharge and 6 weeks and 1 year later.

MAIN RESULTS

One hundred forty-three patients (69 received dexamethasone and 74 received placebo) with bacterial meningitis were evaluable: Haemophilus influenzae type b (83), Streptococcus pneumoniae (33), Neisseria meningitidis (24), and three others. Overall, there was no significant difference in auditory outcome between dexamethasone and placebo recipients. Twenty-two children had bilateral moderate or more severe hearing loss at the time of the first ABR. At follow-up, the resolution of hearing impairment was nearly identical for each group. Nine of ten children who remained persistently deaf were deaf at the time of the first ABR. There were no differences in neurologic or developmental outcome between groups.

CONCLUSION

All but one child with persistent bilateral moderate or more severe hearing loss had demonstrable deafness at the time of the first ABR. Dexamethasone did not significantly improve audiologic, neurologic, or developmental outcome in children with bacterial meningitis.

Pyuria and bacteriuria in urine specimens obtained by catheter from young children with fever

Results of urinalysis and culture of 2181 urine specimens obtained by catheter from febrile children aged less than 24 months were analyzed to determine the following: (1) an optimal cutoff point in considering a bacterial colony count clinically "significant," (2) the accuracy of leukocyte esterase and nitrite tests in identification of pyuria and bacteriuria, and (3) the utility of pyuria (defined as > or = 10 leukocytes/mm3) in the discrimination of urinary tract infection from asymptomatic bacteriuria. Among 110 urine cultures with > or = 10,000 colony-forming units per milliliter, 92 (84%) had > or = 100,000 CFU/ml, 10 (9%) had 50,000 to 99,000 CFU/CFU/ml and 8 (7%) had 10,000 to 49,000 CFU/ml. Urine specimens with 1000 to 49,000 CFU/ml were more likely than specimens with > or = 50,000 CFU/ml to yield Gram-positive or mixed organisms (36/60 vs 7/109; p < 0.001). A count of < 10 leukocytes/mm3 was almost invariably associated with a sterile culture; a count of > or = 10 leukocytes/mm3 was found in 93 of 102 patients with > or = 50,000 CFU/ml. The dipstick leukocyte esterase test had sensitivities of 52.9% and 66.7% in detecting > or = 10 leukocytes/mm3 and > or = 20 leukocytes/mm3, respectively. The dipstick nitrite test had a sensitivity of 31.4% in detecting bacteriuria (> or = 50,000 CFU/ml). Acute pyelonephritis was diagnosed by a renal scan with dimercaptosuccinic acid labeled with technetium 99m in 50 (77%) of 65 patients with > or = 10 leukocytes/mm3 but in none of five patients with < 10 leukocytes/mm3 (p < 0.01). The findings in these five patients were consistent with colonization of the urinary tract rather than infection. For urine specimens obtained by catheter, we believe that urinary tract infection is best defined by both a leukocyte count > or 10/mm3 and a CFU count > or = 50,000/ml. This definition almost always discriminates among true urinary tract infection, bacteriuria resulting from contamination of the urine specimen, and asymptomatic bacteriuria.

Recurrent and nonresolving pneumonia in children

Recurrent pneumonia is defined as two episodes of pneumonia in 1 year or three episodes over any time frame. Nonresolving pneumonias are characterized by the persistence of symptoms and roentgenographic abnormalities for more than 1 month. The key step in evaluating the patient referred for recurrent or persistent pneumonia is to review the clinical and radiographic features of the episodes to determine if there is adequate documentation to proceed with treatment. After deciding that a patient has had a persistent episode of pneumonia or the requisite number of recurrent episodes of pneumonia (accompanied by radiographic evidence of pulmonary infiltrates), it is essential to classify the episodes into those involving single or multiple lobes. On the basis of this classification, the differential considerations and subsequent evaluation are determined.

Comparison of two antigen assays for rapid intrapartum detection of vaginal group B streptococcal colonization

As part of a clinical investigation evaluating the efficacy of intrapartum antigen detection for screening for heavy vaginal colonization with group B streptococci (GBS), we compared the performance of modified Bactigen and Directigen GBS latex particle agglutination (LPA) kits. Paired vaginal swabs obtained from women in labor were rapidly transported to the laboratory and used for culturing (both swabs) and LPA testing (one swab by each method). GBS growth was estimated semiquantitatively and further designated as light or heavy growth. Performance specifications for each method were determined by comparing LPA and culture results from the same swab. A total of 4,251 paired swabs were evaluated during the study period. The performance specifications for detecting GBS growth of any degree for Bactigen and Directigen, respectively, were as follows: sensitivity, 20 and 24%; specificity, 99 and 99%. The performance specifications for heavy colonization for Bactigen and Directigen, respectively, were as follows: sensitivity, 57 and 62%; specificity, 99 and 99%. Neither LPA kit was a sensitive indicator of vaginal colonization with GBS or neonatal infection.

Microbiology of acute and chronic sinusitis in children

To determine the bacteriologic cause of acute sinusitis, a sample of sinus secretions must be obtained from one of the paranasal sinuses without contamination by normal respiratory or oral flora that colonize mucosal surfaces. When maxillary sinus aspiration is performed on children who have signs and symptoms of acute sinusitis, bacteria are recovered in high density from 70%. In patients with acute, subacute, or chronic sinusitis who are generally well except for persistent respiratory symptoms, of nasal discharge or cough or both, the usual bacterial isolates are Streptococcus pneumoniae, Haemophilus influenzae, an Moraxella catarrhalis. In contrast, anaerobic organisms and staphylococci should be suspected in patients who have very long-standing symptoms or in those whose symptoms are so severe or complicated that sinus surgery is undertaken.

Antimicrobial therapy of pediatric patients with sinusitis

The mainstay of medical therapy for acute and subacute sinusitis is the selection of an antimicrobial agent based on an appreciation of the usual bacterial pathogens that include Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Amoxicillin is appropriate therapy for patients with uncomplicated sinusitis in geographic areas in which the prevalence of beta-lactamase-producing pathogens is less than 20%. If a patient does not respond to amoxicillin or in areas in which there is a high prevalence of beta-lactamase-producing bacterial species, alternative antimicrobials include amoxicillin-clavulanate, erythromycin-sulfisoxazole, trimethoprim-sulfamethoxazole, cefaclor, cefuroxime axetil, and cefixime. Cefixime, which is less active against S. pneumoniae than most of these antimicrobials, should be reserved for patients who do not improve with amoxicillin. Amoxicillin-potassium clavulanate, cefuroxime axetil, and erythromycin-sulfisoxazole have the most comprehensive antibacterial spectra.

Respiratory syncytial virus: a comparison of diagnostic modalities

This study compared prospectively viral culture for respiratory syncytial virus (RSV) with three rapid RSV antigen detection tests: RSV EIA and TestPack RSV (TP), and Directigen RSV (DIR). Additionally two methods of specimen collection were compared: nasopharyngeal rub (RUB) and nasopharyngeal wash (WASH). True positives were defined as positive RSV viral culture or at least two positive antigen tests. One hundred ninety-eight WASH specimens obtained from children 3 years of age or younger during the 1991 RSV winter epidemic were tested for RSV antigen. Sensitivity and specificity of WASH specimens were 59.5 and 100% (culture), 86.2 and 98.2% (RSV EIA), 91 and 96.3% (TP) and 83.5 and 94.3% (DIR). Concurrently obtained RUB samples from 124 children were tested by TP and/or DIR. Sensitivity of RUB specimens was significantly lower than that of WASH specimens; 64.9% (TP) and 43.6 (DIR). These easy to perform, rapid RSV antigen tests for WASH specimens provide timely diagnosis thereby facilitating management decisions and isolation efforts.

Efficacy of antimicrobial prophylaxis and of tympanostomy tube insertion for prevention of recurrent acute otitis media: results of a randomized clinical trial

To determine the efficacy of amoxicillin prophylaxis and of tympanostomy tube insertion in preventing recurrences of acute otitis media, we randomized 264 children 7 to 35 months of age who had a history of recurrent otitis media but were free of middle ear effusion to receive either amoxicillin prophylaxis, bilateral tympanostomy tube insertion or placebo. The average rate of new episodes per child year of either acute otitis media or otorrhea was 0.60 in the amoxicillin group, 1.08 in the placebo group and 1.02 in the tympanostomy tube group (amoxicillin vs. placebo, P less than 0.001; tubes vs. placebo, P = 0.25). The average proportion of time with otitis media of any type was 10.0% in the amoxicillin group, 15.0% in the placebo group and 6.6% in the tympanostomy tube group (amoxicillin vs. placebo, P = 0.03; tubes vs. placebo, P less than 0.001). At the 2-year end point, the rate of attrition was 42.2% in the amoxicillin group, 45.5% in the placebo group and 26.7% in the tympanostomy tube group. Adverse drug reactions occurred in 7.0% of the amoxicillin group and persistent tympanic membrane perforations developed in 3.9% of the tympanostomy tube group. The observed degree of efficacy of amoxicillin prophylaxis and of tympanostomy tube insertion must be viewed in light of the fact that study subjects proved not to have been at as high risk for acute otitis media as had been anticipated and in view of the differential attrition rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Infective agents in the central nervous system

Almost all agents can cause infection within the central nervous system. The extent of infection ranges from diffuse involvement of the meninges, brain, or spinal cord to localized involvement presenting as a space-occupying lesion. Epidemiologic considerations, appreciation of the presenting clinical syndrome (acute bacterial meningitis, acute aseptic meningitis, chronic meningitis, or space-occupying lesion), and cerebrospinal fluid analysis facilitate arrival at a diagnosis.