Childhood Invasive Bacterial Disease in Kathmandu, Nepal (2005-2013)

BACKGROUND

Invasive bacterial disease (IBD; including pneumonia, meningitis, sepsis) is a major cause of morbidity and mortality in children in low-income countries.

METHODS

We analyzed data from a surveillance study of suspected community-acquired IBD in children <15 years of age in Kathmandu, Nepal, from 2005 to 2013 before introduction of pneumococcal conjugate vaccines (PCV). We detailed the serotype-specific distribution of invasive pneumococcal disease (IPD) and incorporated antigen and PCR testing of cerebrospinal fluid (CSF) from children with meningitis.

RESULTS

Enhanced surveillance of IBD was undertaken during 2005-2006 and 2010-2013. During enhanced surveillance, a total of 7956 children were recruited of whom 7754 had blood or CSF culture results available for analysis, and 342 (4%) had a pathogen isolated. From 2007 to 2009, all 376 positive culture results were available, with 259 pathogens isolated (and 117 contaminants). Salmonella enterica serovar Typhi was the most prevalent pathogen isolated (167 cases, 28% of pathogens), followed by Streptococcus pneumoniae (98 cases, 16% pathogens). Approximately, 73% and 78% of pneumococcal serotypes were contained in 10-valent and 13-valent PCV, respectively. Most cases of invasive pneumococcal disease (IPD) were among children ≥5 years of age from 2008 onward. Antigen and PCR testing of CSF for pneumococci, Haemophilus influenzae type b and meningococci increased the number of these pathogens identified from 33 (culture) to 68 (culture/antigen/PCR testing).

CONCLUSIONS

S. enterica serovar Typhi and S. pneumoniae accounted for 44% of pathogens isolated. Most pneumococcal isolates were of serotypes contained in PCVs. Antigen and PCR testing of CSF improves sensitivity for IBD pathogens.

Metabolomic Characterization of Cerebrospinal Fluid from Intracranial Bacterial Infection Pediatric Patients: A Pilot Study

Intracranial bacterial infection remains a major cause of morbidity and mortality in neurosurgical cases. Metabolomic profiling of cerebrospinal fluid (CSF) holds great promise to gain insights into the pathogenesis of central neural system (CNS) bacterial infections. In this pilot study, we analyzed the metabolites in CSF of CNS infection patients and controls in a pseudo-targeted manner, aiming at elucidating the metabolic dysregulation in response to postoperative intracranial bacterial infection of pediatric cases. Untargeted analysis uncovered 597 metabolites, and screened out 206 differential metabolites in case of infection. Targeted verification and pathway analysis filtered out the glycolysis, amino acids metabolism and purine metabolism pathways as potential pathological pathways. These perturbed pathways are involved in the infection-induced oxidative stress and immune response. Characterization of the infection-induced metabolic changes can provide robust biomarkers of CNS bacterial infection for clinical diagnosis, novel pathways for pathological investigation, and new targets for treatment.

L-lactate in cerebrospinal fluid can be used as a biomarker of encephalitis in cattle

Cerebrospinal fluid (CSF) changes are significant for antemortem diagnoses of some neurological diseases. The aim of this study was to evaluate if the concentration of L-lactate in CSF could be used to differentiate healthy from encephalitic cattle. Cerebrospinal fluid samples from healthy cattle (n = 10) and from those naturally affected by rabies (n = 15), bovine herpesvirus type 5 meningoencephalitis (n = 16), histophilosis (n = 6), or bacterial encephalitis (n = 4), including 1 case of listeriosis, were collected and analyzed. Physical, biochemical (i.e., protein and glucose), and cellular analyses were performed in fresh samples. L-lactate, electrolytes (sodium, potassium, and chloride), calcium, and magnesium concentrations were measured in CSF samples that were kept frozen. L-lactate concentrations were also measured in plasma. Analysis of variance was used for comparison between groups and receiver operating characteristic analysis was performed considering L-lactate in CSF of healthy versus encephalitic cattle. The CSF L-lactate concentration was significantly higher in cattle with bacterial encephalitis than in healthy cattle; however, it did not differ between viral and bacterial encephalitis. The calcium concentrations were lower in cattle with encephalitis. L-lactate concentration in CSF > 3.6 mmol/L can be accepted as a cut-off value to indicate encephalitis. Thus, L-lactate in CSF is important for the diagnosis of encephalitis in cattle. Despite the small number of cases of bacterial encephalitis, it is suggested that L-lactate was not important for the differentiation between viral and bacterial encephalitis. Additional studies with a greater number of observations are necessary to clarify this, specifically in cases of listeriosis.

Higher Procalcitonin Level in Cerebrospinal Fluid than in Serum Is a Feasible Indicator for Diagnosis of Intracranial Infection

Objective: To explore the value of the difference in procalcitonin (PCT) levels in serum and cerebrospinal fluid (CSF) for diagnosing intracranial infection in post-neurosurgical patients. Methods: Patients who were treated at our hospital after craniotomy from January 2015 to January 2019 were enrolled in this study. Twenty patients eventually diagnosed with intracranial infection were included in a study group and 22 patients with no intracranial infection were included in a control group. A t-test was used to compare the differences between serum and CSF PCT levels of PCT, and the diagnostic value of PCT was evaluated by receiver operating characteristic (ROC) curve analysis. Results: The serum PCT levels in the study and control groups were 0. 10 ± 0. 03 ng/mL and 0. 09 ± 0. 03 ng/mL, respectively, and they were not substantially different between the groups. The CSF PCT level in the study group was substantially higher than that in the control group, with values of 0. 13 ± 0. 03 ng/mL and 0. 07 ± 0. 02 ng/mL, respectively. The CSF/serum PCT ratio in the study group was substantially higher than that in the control group, with values of 1. 31 ± 0. 19 and 0. 79 ± 0. 23, respectively. The areas under the ROC curve for serum PCT, CSF PCT and the CSF/serum PCT ratio were 0. 56, 0. 92, and 0. 95, respectively, resulting in a substantial difference among the three groups. Conclusion: CSF PCT may be a valuable marker for diagnosing intracranial infection in patients after neurosurgery; in particular, the specificity of CSF PCT is higher if the CSF PCT level is higher than the serum PCT level.

Infectious causes and outcomes in patients presenting with cerebral spinal fluid pleocytosis

To evaluate the infectious etiologies, clinical features, and outcomes of patients with CNS infections at a tertiary care center. Patients that present with a pleocytosis in the cerebral spinal fluid (CSF), defined as a CSF WBC count > 5 cells/mm³, from July 2015 to June 2016 at a tertiary care hospital were analyzed for this report. Data from patients with confirmed (n = 43) and presumed (n = 51) CNS infections were analyzed. CNS infection was the leading known cause of CSF pleocytosis (n = 43, 18% of all patients with a pleocytosis in the CSF), and HSV-2 was identified as the leading causative pathogen (n = 10) followed by varicella zoster virus (n = 5). Fifty-three percent of patients with a pleocytosis in the CSF did not receive a diagnosis. In the patients that did not receive a diagnosis, CNS infection was presumed to be the cause in 51 patients (21% of patients with CSF pleocytosis). The mean time to diagnosis for patients with confirmed CNS infection was 16 days, but time to diagnosis was highly variable depending on the causative pathogen. There was a significant overlap in CSF parameters and peripheral white blood cell counts in patients diagnosed with a viral, bacterial, or fungal infection. Neuroimaging changes were present in only 44% of CNS infections. The overall mortality was 7% for CNS infections, and 17% of patients with a CNS infection had a severe neurologic deficit at presentation while only 3% had a severe deficit at the last neurologic assessment. This study provides new insights into the infectious causes of disease in a cohort of patients with pleocytosis in the CSF. The study provides new insights into the time to diagnosis and outcomes in patients that present with pleocytosis in the CSF.

Rapid identification of nonblood sterile site broth cultures using the FilmArray blood culture identification panel

The FilmArray Blood Culture Identification Panel was validated for nonblood sterile site specimens with clinical impact of rapid identification compared to conventional diagnostics. The panel accurately identified target organisms from 98% of positive broth cultures a median 1.1 day faster than conventional techniques (P < 0.0001) with potential clinical impact in 22% of cases.

[The use of MALDI-TOF MS for direct identification of bacteria in clinical specimens]

MALDI-TOF MS is a method enabling rapid identification of bacteria. This is also important for early initiation of adequate antibiotic therapy in patients with infections. In this review, various methods for direct detection of bacteria in clinical specimens are described. The fundamental part deals with direct identification of bacteria from positive blood cultures. Attention is also paid to identification of bacteria from urine and cerebrospinal fluid. Finally, reliability of the methods is mentioned in comparison with conventional methods.

Validation of Procedural Codes to Identify Infants Evaluated for Serious Bacterial Infection

OBJECTIVE

To validate a novel coding method using Current Procedural Terminology, Fourth Edition (CPT-4) codes for identifying infants who underwent a full evaluation for serious bacterial infection (SBI).

METHODS

We performed a multicenter, retrospective examination to determine the accuracy of a combination of CPT-4 codes for blood, cerebrospinal fluid (CSF), and urine cultures to identify previously healthy infants ≤90 days old admitted to a general care floor and fully evaluated for SBI. Full SBI evaluation was defined as blood, CSF, and urine cultures performed during the emergency department encounter or corresponding hospitalization. Cases were defined as infants who had codes for blood, CSF, and urine cultures (87040, 87070, and either 87086 or 87088), and these were compared with all other encounters. We validated these findings by comparing medical record documentation of blood, CSF, and urine cultures to the corresponding CPT-4 codes, with calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

We identified 8548 qualifying encounters, and 347 (4%) had a combination of CPT-4 codes 87040, 87070, and either 87086 or 87088. This combination had a sensitivity of 100% (95% confidence interval, 98.9-100) and specificity of 98.2% (95% confidence interval, 97.3-98.8) for identifying infants who underwent full SBI evaluation for an unknown source.

CONCLUSIONS

CPT-4 codes provide an accurate means to identify infants who underwent complete SBI evaluation.

Characteristic Cytokine and Chemokine Profiles in Encephalitis of Infectious, Immune-Mediated, and Unknown Aetiology

Background

Encephalitis is parenchymal brain inflammation due to infectious or immune-mediated processes. However, in 15–60% the cause remains unknown. This study aimed to determine if the cytokine/chemokine-mediated host response can distinguish infectious from immune-mediated cases, and whether this may give a clue to aetiology in those of unknown cause.

Methods

We measured 38 mediators in serum and cerebrospinal fluid (CSF) of patients from the Health Protection Agency Encephalitis Study. Of serum from 78 patients, 38 had infectious, 20 immune-mediated, and 20 unknown aetiology. Of CSF from 37 patients, 20 had infectious, nine immune-mediated and eight unknown aetiology.

Results

Heat-map analysis of CSF mediator interactions was different for infectious and immune-mediated cases, and that of the unknown aetiology group was similar to the infectious pattern. Higher myeloperoxidase (MPO) concentrations were found in infectious than immune-mediated cases, in serum and CSF (p = 0.01 and p = 0.006). Serum MPO was also higher in unknown than immune-mediated cases (p = 0.03). Multivariate analysis selected serum MPO; classifying 31 (91%) as infectious (p = 0.008) and 17 (85%) as unknown (p = 0.009) as opposed to immune-mediated. CSF data also selected MPO classifying 11 (85%) as infectious as opposed to immune-mediated (p = 0.036). CSF neutrophils were detected in eight (62%) infective and one (14%) immune-mediated cases (p = 0.004); CSF MPO correlated with neutrophils (p<0.0001).

Conclusions

Mediator profiles of infectious aetiology differed from immune-mediated encephalitis; and those of unknown cause were similar to infectious cases, raising the hypothesis of a possible undiagnosed infectious cause. Particularly, neutrophils and MPO merit further investigation.

Molecular diagnosis of central nervous system opportunistic infections in HIV-infected Zambian adults

BACKGROUND

Knowledge of central nervous system (CNS) opportunistic infections (OIs) among people living with human immunodeficiency virus (HIV) in sub-Saharan Africa is limited.

METHODS

We analyzed 1 cerebrospinal fluid (CSF) sample from each of 331 HIV-infected adults with symptoms suggestive of CNS OI at a tertiary care center in Zambia. We used pathogen-specific primers to detect DNA from JC virus (JCV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) types 1 and 2, Mycobacterium tuberculosis, and Toxoplasma gondii via real-time polymerase chain reaction (PCR).

RESULTS

The patients' median CD4(+) T-cell count was 89 cells/µL (interquartile range, 38-191 cells/µL). Of 331 CSF samples, 189 (57.1%) had at least 1 pathogen. PCR detected DNA from EBV in 91 (27.5%) patients, M. tuberculosis in 48 (14.5%), JCV in 20 (6.0%), CMV in 20 (6.0%), VZV in 13 (3.9%), HSV-1 in 5 (1.5%), and HSV-2 and T. gondii in none. Fungal and bacteriological studies showed Cryptococcus in 64 (19.5%) patients, pneumococcus in 8 (2.4%), and meningococcus in 2 (0.6%). Multiple pathogens were found in 68 of 189 (36.0%) samples. One hundred seventeen of 331 (35.3%) inpatients died during their hospitalization. Men were older than women (median, 37 vs 34 years; P = .01), more recently diagnosed with HIV (median, 30 vs 63 days; P = .03), and tended to have a higher mortality rate (40.2% vs 30.2%; P = .07).

CONCLUSIONS

CNS OIs are frequent, potentially treatable complications of AIDS in Zambia. Multiple pathogens often coexist in CSF. EBV is the most prevalent CNS organism in isolation and in coinfection. Whether it is associated with CNS disease or a marker of inflammation requires further investigation. More comprehensive testing for CNS pathogens could improve treatment and patient outcomes in Zambia.

[Low-manifest infections with CNS damage in patients in prolonged unconscious state of non-inflammatory etiology]

AIM

Study of specter of low-manifest infections (LMI) with central nervous system (CNS) damage and their role in patients in prolonged unconscious state (PUS) of noninflammatory etiology.

MATERIALS AND METHODS

32 patients (23 male, 9 female; age 14-58) in PUS of various etiology were examined. The main group (18 patients) received therapy against all infectious diseases including LMI; control group (14 patients)--only against common and nosocomial microflora. Patients were immunologically, infectologically and neurologically examined in dynamic. The data obtained were treated by using STATISTICA for Windows (version 5.5).

RESULTS

Significant differences in immune and infectologic status depending on the nature of primary CNS damage were not detected. Immunodeficiency was detected in all patients; 94% of patients had increased non-specific IgM and IgE. Among LMI agents Chlamydia spp. were predominant. Cultural and/or PCR methods detected this microorganism during the primary examination in cerebrospinal fluid samples in 56% patients and in blood samples in 56%; during the second diagnostics or autopsy--only in 13 and 25%, respectively. Detection of Bacteroides fragilis, Human Herpes Virus (HHV-6), Virus Epstein Barr (VEB), Cytomegalovirus (CMV) in cerebrospinal fluid, blood and on mucous membranes of nasopharynx and conjunctiva was grouped more frequently with the presence of Chlamydia spp. in the CNS (p < 0.05) than with other LMI agents. Sanation of CNS from LMI was significantly accompanied by regeneration of communicative activity in comparison with the control group.

CONCLUSION

In patients with PUS high frequency of CNS infection by various LMI agents and primarily Chlamydia spp. should be considered. Sanation from LMI can become a "window" for effective neuro-regenerative treatment.

[Etiology and results of treatment of adults with bacterial encephalomeningitis]

Results of treatment and outcomes of 89 adults with purulent encephalomeningitis, treated in years 1996-2002 in the Department of Infectious Diseases and Hepatology, Medical University of Lodz, were analyzed. Eighty nine patients were retrospectively included into the study. Results of treatment were evaluated at the last day of patient's hospitalization, and classified as: cure, disability or death. Results of treatment were analyzed in relation to etiology of purulent encephalomeningitis, age and gender of patients, course of the disease, and time from the onset of symptoms to admission to the Department. No statistically significant correlations between age, gender and prognosis were found. Thirty seven out of 89 patients were cured (41.6%); 29 of 89 patients died (32.6%); in 18 patients (19/89; 20.2) disability was diagnosed. In remaining 5 cases (5.6%), the result of treatment remained unknown. These patients were transferred to Intensive Care Units, outside our Hospital. In the studied group, etiologic factor was identified in 40 out of 89 cases (44.9%). In 40 patients, positive results of bacterial examination of cerebrospinal fluid were achieved. In 22 out of these 40 cases (55.0%), Streptococcus pneumoniae was identified as the etiologic factor. Higher percentage of patients died in subgroup with known etiology than in in subgroup of unknown etiology (p = 0.02). Higher percentage of cases with unconsciousness and higher percentage of cases with respiratory insufficiency were diagnosed in patients who died, than in patients who were cured (p = 0.00001).

CONCLUSION

1. Purulent meningoencephalitis in adults, despite progress in antibiotic treatment, is still a serious condition, with poor prognosis. 2. Diagnostics and treatment modalities of purulent meningo-encephalitis should be urgently extended in order to achieve better outcomes in these group of patients.

Toxoplasmosis encephalitis following severe graft-vs.-host disease after allogeneic hematopoietic stem cell transplantation: 17 yr experience in Fukuoka BMT group

Toxoplasmosis is a rare but rapidly fatal complication that can occur following hematopoietic stem cell transplantation (HSCT). Over a 17-yr period at our institutions, a definite diagnosis of toxoplasmosis was made in only two of 925 allogeneic HSCT recipients (0.22%) and none of 641 autologous HSCT recipients. These two patients received a conventional conditioning regimen followed by transplantation from an HLA-matched donor; however, they developed severe graft-vs.-host disease, which required intensive immunosuppressive therapy. Despite prophylactic treatment with trimethoprim/sulfamethoxazole, their immunosuppressive state, as indicated by a low CD4(+) cell count, might have resulted in toxoplasmosis encephalitis. Rapid and non-invasive methods such as a polymerase chain reaction (PCR) test of their cerebrospinal fluid for Toxoplasma gondii and magnetic resonance imaging of the brain were useful for providing a definitive diagnosis and prompt therapy in these patients: one patient stabilized and survived after responding to treatment with pyrimethamine/sulfodiazine whereas the other died of bacterial infection. In addition, retrospective PCR analyses of the frozen stored peripheral blood samples disclosed that detection of T. gondii preceded the onset of disease, indicating routine PCR testing of peripheral blood specimens may be an early diagnostic tool. It should be noted that when patients receiving HSCT have an unexplained fever and/or neurological complications, PCR tests should be considered to avoid cerebral lesions and improve the outcome of the patients.

Complications following endoscopic intracranial procedures in children

BACKGROUND

The significant technological improvement of endoscopic instrumentation has allowed, in the last 10 years, a widespread diffusion of neuroendoscopic procedures. Nevertheless, severe, sometimes life-threatening, complications may occur during neuroendoscopic surgery, and the incidence and age specificity of complications in children have been underdescribed so far.

MATERIALS AND METHODS

Complications recorded in a prospectively collected database of pediatric patients undergoing neuroendoscopic procedures were analysed; the medical histories of the patients and the surgical procedures were reviewed.

RESULTS

Complications occurred in 32 out of 231 (13.8%) procedures performed for the management of obstructive hydrocephalus (137), multiloculated hydrocephalus (53), arachnoid cysts (29) and intraventricular tumors (12). Subdural hygroma occurred in 11 cases, seven requiring subdural shunting. In one of these cases, infection of the subdural space occurred and required a craniotomy. Cerebrospinal fluid (CSF) infection occurred in 11 cases. In one case, a frontal abscess developed and was managed with craniotomy. CSF leak occurred in nine cases, intraventricular haemorrhages in two, technical failures in seven, subcutaneous CSF collection (managed with lumbo-peritoneal shunt) in one, thalamic contusion and post-operative transient akinetic mutism in one. This patient suddenly died 6 months later, probably as a consequence of closure of the stoma. Two patients developed secondary compartmentalisation of the ventricles after complicated endoscopic third ventriculostomy. In nine cases, these complications were associated. Overall, no patient died after the procedure (operative mortality 0), one patient died 6 months after the procedure for unexplained events (sudden death rate 0.4%), and three patients presented permanent disability as a consequence of surgical complication (permanent morbidity 1.3%).

CONCLUSIONS

Complication rate of neuro-endoscopic procedures is not negligible even in experienced hands. The majority are minor complications which do not affect the final outcome, but sporadically major events may occur, leading to significant problems in surgical management and, occasionally, to permanent disabilities. Careful selection of patients on pre-operative imaging studies and intensive training of surgeons are mandatory to improve results.

Endotoxin fever in granulocytopenic rats: evidence that brain cyclooxygenase-2 is more important than circulating prostaglandin E2

PGE(2) is a recognized mediator of many fevers, and cyclooxygenase (COX) is the major therapeutic target for antipyretic therapy. The source, as well as the site of action of PGE(2), as an endogenous pyrogen, is widely accepted as being central, but PGE(2) in the circulation, possibly from leukocytes, may also contribute to the development of fever. However, bacterial infections are important causes of high fever in patients receiving myelosuppressive chemotherapy, and such fevers persist despite the use of COX inhibitors. In the study reported here, the febrile response to bacterial LPS was measured in rats made leukopenic by cyclophosphamide. A striking increase in LPS fever occurred in these granulocytopenic rats when compared with febrile responses in normal animals. Unlike LPS fever in normal rats, fever in granulocytopenic rats was neither accompanied by an increase in blood PGE(2) nor inhibited by ibuprofen. Both leukopenic and normal rats showed LPS-induced COX-2-immunoreactivity in cells associated with brain blood vessels. Furthermore, LPS induced an increase of PGE(2) in cerebrospinal fluid. Induction of COX-2-expression and PGE(2) production was inhibited by ibuprofen in normal but not in leukopenic rats. Although the results presented are, in part, confirmatory, they add new information to this field and open a number of important questions as yet unresolved. Overall, the present results indicate that, in contrast to immunocompetent rats, leukocytes and/or other mechanisms other than PGE(2) are implicated in the mechanisms restricting and reducing the enhanced febrile response to endotoxin in immunosuppressed hosts.

Serum and cerebrospinal fluid concentrations of linezolid in neurosurgical patients

Linezolid is a new antimicrobial agent effective against drug-resistant gram-positive pathogens commonly responsible for central nervous system (CNS) infections in neurosurgical patients hospitalized in intensive care units. In order to study the penetration of this antimicrobial into the cerebrospinal fluid (CSF) of such patients, the disposition of linezolid in serum and CSF was studied in 14 neurosurgical patients given linezolid at 600 mg twice daily (1-h intravenous infusion) for the treatment of CNS infections caused by gram-positive pathogens or for prophylactic chemotherapy. Serum and CSF linezolid steady-state concentrations were analyzed by high-pressure liquid chromatography, and the concentration-time profiles obtained were analyzed to estimate pharmacokinetic parameters. The mean +/- standard deviation (SD) linezolid maximum and minimum measured concentrations were 18.6 +/- 9.6 microg/ml and 5.6 +/- 5.0 microg/ml, respectively, in serum and 10.8 +/- 5.7 microg/ml and 6.1 +/- 4.2 microg/ml, respectively, in CSF. The mean +/- SD areas under the concentration-time curves (AUCs) were 128.7 +/- 83.9 microg x h/ml for serum and 101.6 +/- 59.6 microg x h/ml for CSF, with a mean penetration ratio for the AUC for CSF to the AUC for serum of 0.66. The mean elimination half-life of linezolid in CSF was longer than that in serum (19.1 +/- 19.0 h and 6.5 +/- 3.6 h, respectively). The serum and CSF linezolid concentrations exceeded the pharmacodynamic breakpoint of 4 microg/ml for susceptible target pathogens for the entire dosing interval in the majority of patients. These findings suggest that linezolid may achieve adequate concentrations in the CSF of patients requiring antibiotics for the management or prophylaxis of CNS infections caused by gram-positive pathogens.

Efficacy of antimicrobial-impregnated external ventricular drain catheters: a prospective, randomized, controlled trial

OBJECT

Catheter-related infection of the cerebrospinal fluid (CSF) pathways is a potentially life-threatening complication of external ventricular drainage. A major source of infection is bacterial contamination along the external ventricular drain (EVD) catheter track. The authors examined the efficacy of EVD catheters impregnated with minocycline and rifampin in preventing these catheter-related infections.

METHODS

The authors conducted a prospective, randomized clinical trial at six academic medical centers. All hospitalized patients 18 years or older who required placement of an EVD catheter were eligible for inclusion in the study. Patients were randomly assigned to undergo placement of an EVD with a catheter impregnated with minocycline and rifampin or a standard untreated catheter (control group). To assess primary outcome, CSF samples were collected using a sterile technique at the time of catheter insertion, at least every 72 hours while the catheter remained in place, and at the time of catheter removal. At the time of removal, CSF cultures were obtained from the tip and tunneled segments of each catheter by performing semiquantitative roll-plate and quantitative sonication techniques. Of the 306 patients enrolled in the study, data from 288 were included in the final analysis. Eighteen patients were excluded from analysis: 14 because the ventricular catheter was in place less than 24 hours, and four because CSF cultures obtained at the time of catheter insertion were positive for infection. Of these 288 patients, 139 were assigned to the control group and 149 to the treatment group. The two groups were well matched with respect to all clinical characteristics, including patient sex and mean age, indication for catheter placement, and length of time the catheter remained in place. The antibiotic-impregnated catheters were one half as likely to become colonized as the control catheters (17.9 compared with 36.7%, respectively, p < 0.0012). Positive CSF cultures were seven times less frequent in patients with antibiotic-impregnated catheters compared with those in the control group (1.3 compared with 9.4%, respectively, p = 0.002).

CONCLUSIONS

The use of EVD catheters impregnated with minocycline and rifampin can significantly reduce the risk of catheter-related infections.

[Disturbances of cerebral perfusion in patients with bacterial meningoencephalitis]

The investigations were done in acute and reconvalescent phase in 34 patients with bacterial meningoencephalitis. Neurologic condition, degree of the brain injury on the basis of Glasgow Coma Scale (GCS), protein level and pleocytosis in cerebrospinal fluid (CSF), and regional cerebral blood flow on dynamic computed tomography (CT) were assessed. The brain blood flow was measured in the white matter of the frontal and occipital horns of lateral ventricles, symmetrically in both hemispheres. Statistically significant reduction of the brain perfusion in acute phase of illness was improved. In reconvalescent phase normalisation of the brain blood supply was observed. 56% of patients had changes of consciousness. There was no significant correlation between these symptoms and parameters describing blood supply. The rest of patients had neurologic abnormalities: seizure, pyramidal syndrome, injury of the central nerves due to the reduction of blood flow in selected regions of the brain. Patients who aggregated low GCS score had high inflow of the blood. In patients who were in better condition, inflow was smaller. High pleocytosis in CSF was associated with small blood inflow and perfusion in investigated regions of the brain. Whereas high protein concentration correlated with higher inflow and increase in regional perfusion. We consider, that the brain blood supply correlate with intensification of inflammatory response in CSF.

[Recurrent purulent bacterial meningoencephalitis]

During the period of 25 years there were 55 patients treated in our Institute because of recurrent purulent bacterial meningoencephalitis(rpbme). This group consisted of 42 males (76%) and 13 (24%) females, the prevalent number (53%) of patients being under 21 years of age. The diagnosis of rpbme was based on the commonly accepted criteria and confirmed by the laboratory results of CSF examination. The cause of the recurrences was established considering the skull X-ray examination, CT and MRI. The evaluation of the clinical status was based on the Glasgow Coma Score (GCS). During the first hospitalisation, severe or critic clinical status was noted in 42 patients (76%) and moderate in 13 (24%). The subsequent recurrences were mostly moderate, rarely severe or mild. The number of recurrences varied from 1 to 9. During the first hospitalisation, the etiologic factor was detected in 39 patients (71%), i.e. Streptococcus pneumoniae in 28 (51%), Neisseria meningitidis in 8 (14%), Pseudomonas aeruginosa and Staphylococcus aureus in 2 and 1 patients respectively. In 37 patients (67%) rpbme developed following cranial trauma, in 18 cases (33%) with single or comminuted fractures of the anterior cranial fossa (in 4 cases accompanied by CSF nasal exsudate). In 4 it followed neurosurgical intervention, in 3 it accompanied recurrent purulent highmorities, in 1 case--after removal of the nasal polyps and subsequent CSF nasal exsudate, and in 1 patient with recurrent mastoiditis. In 6 cases (11%) the cause of the recurrences remained unelucidated. The clinical signs and symptoms, diagnostic difficulties and the causative treatment of rpbme are discussed. In the authors' opinion, surgical treatment of the communication between the CSF and the external environment prevents the recurrences and is the only successful way of treatment. Special attention is drawn to the great diagnostic value of CT and MRI. The use of other modern techniques, e.g. positron emission tomography (PET) is recommended, because it is useful not only in the functional evaluation of the cerebral tissue after the injury, but also in assessing the dynamics of pathologic changes.

Differential fluorescent staining method for detection of bacteria in blood cultures, cerebrospinal fluid and other clinical specimens

The aim of this study was to evaluate a differential staining method to distinguish gram-positive from gram-negative bacteria in fluorescence. The method is based on two fluorochromes, one acting in the wavelength of red, i.e. the acridine orange, and another acting in the wavelength of green, i.e. the fluorescein. With this method, gram-positive bacteria appear yellow and gram-negative bacteria appear green. In view of the importance of a rapid aetiological diagnosis in cases of septicaemia, the differential staining method in fluorescence was compared with Gram stain for the detection of bacteria in blood. Of 5,820 blood cultures entered into the study and identified by the Bactec 9120 fluorescent series instrument (Becton Dickinson Europe, France), 774 were positive. Of the 774 positive cultures, 689 yielded only a single organism. The differential staining method in fluorescence detected 626 of the 689 cultures, while Gram stain detected 468. On the basis of these results, the sensitivity of the differential staining method in fluorescence was 90.9%, while that of Gram stain was 67.9%. The difference between the two methods was statistically significant ( P<0.001). The differential fluorescent staining method was more sensitive than Gram stain in the detection of bacteria in blood cultures during the incubation period. This technique provides a rapid, simple and highly sensitive staining method that can be used in conjunction with subculture methods. Whereas subculture requires an incubation period of 18-24 h, the fluorescent staining technique can detect bacteria on the same day that smears are prepared and examined. The differential fluorescent staining method was also evaluated for its ability to detect microorganisms in cerebrospinal fluid and other clinical specimens. The microorganisms were easily detected, even when bacterial counts in the specimens were low.

Children with first-time simple febrile seizures are at low risk of serious bacterial illness

OBJECTIVE

To describe the rates of serious bacterial illness (SBI) in children presenting to emergency departments (EDs) with first-time uncomplicated febrile seizures.

METHODS

The ED visits from seven Chicago metropolitan area hospitals (two tertiary pediatric EDs, five community general EDs) for all pediatric patients seen between July 1995 and December 1997 with a discharge diagnosis including the term "seizure" were retrospectively identified. Records of patients who met criteria for simple, first-time febrile seizure were reviewed (age 6-60 months; temperature > or =38.0 degrees C; single, generalized, tonic-clonic seizure <20 minutes; absence of known central nervous system disease). Rates of bacteremia, urinary tract infection, bacterial meningitis, and pneumonia were determined.

RESULTS

Four hundred fifty-five children were identified who had first-time simple febrile seizures. The study participants had a mean age of 21 months and a mean temperature of 39.6 degrees C, and 64% were male. Seventy-three percent were seen in a community hospital setting. Blood cultures were obtained for 315 children (69%). Four children (1.3% [95% CI = 0.1% to 2.5%]) were bacteremic, all with Streptococcus pneumoniae; the rate of bacteremia did not differ in the subset at highest risk for bacteremia (6-36 months, temperature >39 degrees C). No demographic or laboratory data distinguished the bacteremic children from those with negative blood cultures. One hundred seventy-one children (38%) had urine cultures obtained; 5.9% [95% CI = 2.4% to 9.4%] of the cultures grew >100,000 colony-forming units/mL of a single pathogenic organism. One hundred thirty-five children (30%) had cerebrospinal fluid cultures performed. None of these cultures grew a bacterial pathogen [95% CI = 0% to 2.2%]. Two hundred eight children (45.7%) had chest x-rays performed; 12.5% [95% CI = 10.2% to 14.8%] (n = 26) of the x-rays were read as consistent with pneumonia by the radiologist at the treating institution. None of the blood cultures performed on children with abnormal radiographs were positive (cultures drawn on 23 of 26 patients, 88%). Stool cultures were performed on 14 children (3.1%); two cultures (14.3% [95% CI = 0% to 32.6%]) grew a bacterial pathogen, both Shigella.

CONCLUSIONS

Rates of SBI in this multi-institution population of children with first-time simple febrile seizures were low and are consistent with those published in the literature for febrile children without seizures.

Cerebrospinal fluid

A quick and accurate diagnosis of maladies affecting the central nervous system (CNS) is imperative. Procurement and analysis of cerebrospinal fluid (CSF) are paramount in helping the clinician determine a patient's clinical condition. Various staining methods, measurement of white blood cell counts, glucose and protein levels, recognition of xanthochromia, and microbiologic studies are CSF parameters that are collectively important in the ultimate determination by a clinician of the presence or absence of a catastrophic CNS condition. Many of these CNS parameters have significant limitations that should be recognized to minimize under treating patients with catastrophic illness.

Cerebrospinal fluid analysis: disease-related data patterns and evaluation programs

Cerebrospinal fluid (CSF) analysis is a basic tool for diagnosis of neurological diseases. Knowledge regarding blood-CSF barrier function (molecular flux/CSF flow theory) and neuroimmunology is reviewed to aid understanding and evaluation of CSF data. Disease-related immunoglobulin patterns (IgG, IgA, IgM with reference to albumin) are described in CSF/serum quotient diagrams with the hyperbolic reference range for blood-derived protein fractions in CSF. Clinical relevance of complementary analyses (cytology, PCR, oligoclonal IgG, antibody detection and brain-derived proteins) is briefly discussed. Integrated CSF data reports are shown with numerical and graphical data representation, reference range-related interpretation and diagnosis-related comments. The principles and rationale of general CSF analysis reported in this review should enable the reader to accurately interpret CSF data profiles, and to plan a proper evaluation of new brain- or blood-derived analytes in CSF.

Lumbar and ventricular CSF protein, leukocytes, and lactate in suspected bacterial CNS infections

Protein concentration, leukocyte density, and lactate concentration were studied in 41 pairs of ventricular and lumbar CSF drawn at an interval of less than 24 hours from patients with suspected bacterial CNS infections. The ventriculo-lumbar ratios ranged from 0.003 to 10.2 (median=0.42) for protein and from 0.002 to 53.5 (median=0.17) for leukocytes. The uneven distribution of leukocytes and proteins in the CSF space may produce findings that fail to indicate bacterial CNS infections. Lactate was distributed more homogeneously in the CSF space than protein and leukocytes (ventriculo-lumbar ratio 0.52 to 1.66 [median=0.811).

Pharmacokinetic optimisation of the treatment of bacterial central nervous system infections

Central nervous system (CNS) infections caused by bacteria with reduced sensitivity to antibacterials are an increasing worldwide challenge. In successfully treating these infections the following conditions should be considered: (i) Antibacterials do not distribute homogeneously in the central nervous compartments [cerebrospinal fluid (CSF), extracellular space of the nervous tissue, intracellular space of the neurons, glial cells and leucocytes]. Even within the CSF, after intravenous administration, a ventriculo-lumbar concentration gradient is often observed. (ii) Valid parameters of drug entry into the CSF are the CSF: serum concentration ratio in steady state and the CSF: serum ratio of the area under the concentration-time curves (AUCCSF/AUCS). Frequently, the elimination half-life (t1/2 beta) in CSF is longer than t1/2 beta in serum. (iii) For most antibacterials, lipophilicity, molecular weight and serum protein binding determine the drug entry into the CSF and brain tissue. With an intact blood-CSF and blood-brain barrier, the entry of hydrophilic antibacterials (beta-lactam antibacterials, glycopeptides) into the CNS compartments is poor and increases during meningeal inflammation. More lipophilic compounds [metronidazole, quinolones, rifampicin (rifampin) and chloramphenicol] are less dependent on the function of the blood-CSF and blood-brain barrier. (iv) Determination of the minimal inhibitory concentrations (MIC) of the causative organism is necessary for optimisation of treatment. (v) For rapid sterilisation of CSF, drug concentrations of at least 10 times MIC are required. The minimum CSF concentration: MIC ratio ensuring successful therapy is unknown. Strategies to achieve optimum antibacterial concentrations in the presence of minor disturbances of the blood-CSF and blood-brain barrier include, the increased use of low toxicity antibacterials (e.g., beta-lactam antibiotics), the use of moderately lipophilic compounds, and the combination of intravenous and intraventricular administration. Antibacterials which do not interfere with bacterial cell wall synthesis delay and/or decrease the liberation of proinflammatory bacterial products, delay or inhibit tumour necrosis factor release, and may reduce brain oedema in experimental meningitis. Conclusive evidence of the reduction of neuronal damage by this approach, however, is lacking.

Cerebrospinal fluid broth culture isolates: their significance for antibiotic treatment

Enriched broth medium is routinely used as a supplement for agar plate culture of cerebrospinal fluid (CSF). To assess the clinical utility of broth cultures, 151 consecutive CSF bacterial and fungal isolates obtained from 91 patients were retrospectively reviewed for the effect of results on treatment. Treatment decisions associated with individual CSF specimens for which isolates were recovered from thioglycollate broth only were compared with the treatment decisions associated with CSF specimens for which isolates were recovered by agar plate culture. Treatment was defined as initiation of or change in antimicrobial therapy based on the reporting of CSF culture isolates. Thirty-six (24%) of the 151 isolates were recovered in broth only. Three (8%) of these 36 isolates (from 34 patients) resulted in treatment with antimicrobial agents; however, 2 of the 3 treated isolates (Candida tropicalis, Proteus mirabilis) were recovered from a second CSF specimen in agar plate culture within 24 hours. Thus, only a single isolate (3%; Staphylococcus epidermidis) was treated based solely on a positive broth culture result. In contrast, 60 (52%) of the 115 isolates recovered in agar plate culture from 23 (40%) of 57 patients were treated (staphylococci, 28; gram-negative bacilli, 14; Cryptococcus neoformans, 10; Streptococcus pneumoniae, 3; Streptococcus sanguis, 1; other, 4). We conclude that treatment with antimicrobial agents based on isolates recovered from CSF specimens in broth culture alone is infrequent and infer from the data that the use of CSF broth cultures contributes little to treatment decisions.

[Infections of cerebrospinal fluid shunts in children. Review of 100 infections in 87 children]

An analysis of 100 infections in 87 children treated with shunts in the period of 1982 to 1995 is reported. The clinical presentation has been more frequently secondary to inflammatory signals. Staphylococcus were the most frequently microorganisms found. Infection by Gram negative agents was more aggressive and directly related with failure of therapy. Treatment included since only systemic antibiotics until withdrawal of shunt with use of systemic and intrathecal antibiotics. The best therapeutic results were obtained with withdrawal of shunt system and replacement by external shunt system associated to systemic antibiotics. In our experience this management must be accepted for treatment of this severe complication.

Evaluation of febrile infants under 3 months of age: is routine lumbar puncture warranted?

Fever may be the sole clinically evident presentation of serious bacterial infection (SBI) in a very young infant, and therefore lumbar puncture is still widely regarded as a mandatory procedure in the sepsis workup of febrile infants under 2 months of age. In this retrospective study, we evaluated the frequency and the diagnostic value of cerebrospinal fluid examination in 492 infants aged less than 3 months who were hospitalized because of fever during 1988-1994. The patients were categorized as being at "high risk" or "low risk" for SBI according to current clinical and laboratory criteria. Among the 492 infants, 196 (40%) were identified as "high-risk" for SBI, and 296 (60%) were at low risk. Among the overall series of infants, 60 babies (12%) were subsequently proven with bacterial infection. Among the 196 "high-risk" babies, 26% had bacterial infection, compared to only 3% of the 296 infants at low risk (p < 0.0001), denoting a sensitivity of 85% and a specificity of 65% of the clinical classification criteria. Lumbar puncture was done to 186 (46%) infants upon hospital admission; 176 punctures yielded satisfactory samples of cerebrospinal fluid (CSF). Sixteen (3%) patients had abnormal CSF findings: 2 of them had positive bacterial cultures and 14 were compatible with aseptic meningitis. The 2 patients with purulent meningitis were clinically very ill and were immediately recognized as deserving a lumbar puncture. Of the 14 patients with aseptic meningitis, 13 were initially screened as being at high risk for serious infection, and therefore underwent a lumbar puncture. Over the years of this survey, a declining trend for performing lumbar puncture in "low-risk" young febrile infants became evident: during 1988-1992, evaluation of sepsis included a lumbar puncture in 45% of the infants, compared to 27% during the following 2 years (p < 0.0001). Not one instance of purulent meningitis evolved among the infants in whom lumbar puncture was not performed. Our observations suggest that hospitalized young febrile infants may safely be spared a lumbar puncture when they do not meet the proposed criteria for being at high risk, or when their clinical and laboratory picture suggests being at low risk for SBI.

Shunt malfunction in relation to shunt infection

Ventriculo-peritoneal shunt malfunction may be caused by shunt infection which may not be clinically apparent as the cause of the malfunction by standard diagnostic criteria. This suggests that the real incidence of infected shunts might be higher than previously suspected. In order to study the relationship between infection and shunt malfunction, we followed a protocol over five years (54 V-P shunts) consisting of (1) removal of the malfunctioning shunt and replacement in the same surgical procedure with a new one or institution of an external ventricular drainage for 8 days (if there were clear signs of infection), (2) culturing of CSF and every part of the removed shunt, and (3) intravenous antibiotic treatment (Vancomycin 1g./12h + Ceftriaxone 1g./12h) for five days after the new V-P shunt had been inserted. In those cases in which an external ventricular drainage had been placed, its tip and a portion of the new V-P shunt were also cultured. The results showed that although CSF cultures were negative in 49/54 cases (90.7%), cultures of the removed shunts were positive in 32/54 (59.2%), most of them (21/32, 65.6%) for Staphylococcus coagulase negative organisms. The CSF samples obtained by puncturing the reservoir on admission to Hospital were positive only in 5 out of 54 cases (9.2%), only in those showing clinical features of infection. In the remaining cases, 27 out of 54 (50%) the CSF cultures were negative but the shunt cultures proved positive and required further treatment. For the newly inserted shunts (173) CSF was collected through the shunt during the surgical procedure, and a small piece of the extra-tube from the ventricular and from the peritoneal catheter were obtained and cultured. All the six shunts (6/173, 3.4%) that showed positive cultures after insertion had to be replaced within a period of three to four weeks due to malfunction (range 26 +/- 7 days), indicating that the systematic culture of CSF and tubing helps to predict which shunts will soon need to be replaced due to infection. We conclude that CSF culture alone does not rule out infection in cases of shunt malfunction. The percutaneous CSF obtained from the shunt reservoir admission is particularly prone to show negative cultures even when the shunt is colonized by bacteria.

A flexible metal ventricular catheter for treatment of complicated and protracted infections of the cerebrospinal fluid spaces: preliminary experiences

In the management of shunt infection, the use of ventricular catheters made of silicone rubber for the temporary external drainage of cerebrospinal fluid (CSF) is general practice. However, the eradication of the primary source of infection may be hindered by the affinity of bacteria to silicone-based material. Compared to silicone catheters, a metal drainage device for temporary ventriculostomy appears to offer more favourable conditions for successful eradication of the infection. Since metal needles cannot be implanted permanently and since their screw-type fixation precludes attachment to the skulls of infants or small children, we developed a flexible metal catheter. This catheter was used exclusively for the treatment of particularly serious or chronic infections of the CSF spaces. The catheter is made of implantation steel and consists of a corrugated tube that renders it flexible. Cerebrospinal fluid drains into a receptable bulb at the tip of the tube. Tubing of other materials may be connected to the end of the metal catheter for either external or internal drainage. It was implanted as a temporary and later permanent CSF drainage in 7 male patients aged from 4 to 60 years, who suffered from chronic, recurrent ventriculitis (n = 5) with an average of 7 previous surgical revisions, as well as from complex infections (n = 2; basal tuberculous meningitis, brain abscess). The infections were successfully eliminated in 6 patients. In the remaining patient, the metal catheter for external ventriculostomy had to be removed after 4 days due a leakage of CSF; it was replaced by a silicone catheter and later on by a needle drainage. Other complications, such as secondary infection or intracerebral haemorrhage, did not occur. The average duration of external CSF drainage via the flexible metal catheter was 27 days (range 4-50 days). In 4 patients, the CSF drainage was converted to a permanent ventriculoperitoneal shunt using a new flexible metal catheter. At the time of post-operative follow-up examination (average = 34 weeks), all shunts were functioning and there was no evidence of infection. In cases of especially complicated and protracted CSF infections, the flexible metal ventricular catheter is a promising device for treatment.

[Retrospective analysis of 1331 samples of cerebrospinal fluid in newborn infants with suspected infection]

BACKGROUND

Definitive diagnosis of a neonatal infection usually requires recovery of an etiologic agent from body fluids or tissues such as spinal fluid, blood and urine. Routine lumbar puncture (LP) may raise some problems in interpreting results.

POPULATION AND METHODS

A retrospective analysis of 1331 samples of CSF was made. LP had been performed on 1041 neonates including 569 prematures (54.6%) as a part of the evaluation for suspected bacterial infection.

RESULTS

In 50.7% of the cases, the CSF was haemorrhagic. The frequency of traumatic taps increased with the degree of prematurity, low birth weight, precocity of LP, association with respiratory distress and disorders of coagulating factors. In addition, haemorragic taps modified biochemical and cytologic characteristics of CSF. One hundred and six (8%) CSF samples contained organisms but the diagnosis of meningitis was certain in only 23 cases (2.2%). In the other 83 cases, CSF was thought to be contaminated, mostly by coagulase-negative staphylococci. Since both blood and CSF cultures were positive for the same bacterial organism in 18 cases, it was concluded that the LP had been useful in identifying the pathogens in only five cases. The high frequency of contaminated CSF led to overestimation of the incidence of true bacterial meningitis (0.57% in our study).

CONCLUSIONS

The low incidence of meningitis in neonates, the risk of having an haemorragic tap associated with the possibility of clinical aggravation during LP and the fact that the same pathogen is frequently (78.2% of cases) identified in blood cultures suggest that the immediate and routine LP is of less value than expected in infants suspected to be infected. LP could be postponed when the neonate presents with a respiratory distress syndrome and/or a precarious haemodynamic state.

Cerebrospinal fluid shunt infections in children

We reviewed cerebrospinal fluid (CSF) shunt infections treated in the Royal Children's Hospital, Melbourne from 1981 to 1991. Forty-one episodes of CSF shunt infection were found after 900 shunt operations, an infection rate of 4.5%. Clinical symptoms were nonspecific in 31.7% of episodes, and in 17.1% of episodes the initial CSF sample was normal on microscopy and biochemistry, although a pathogen was isolated on culture. Most episodes occurred within 4 months of the last operation on the shunt, the exception being infections caused by Haemophilus influenzae. Four patients died during treatment, but none could be attributed to infection alone. Treatment of suspected CSF shunt infection should not be withheld because of lack of firm clinical diagnosis or normal CSF microscopy, and episodes occurring more than 4 months after the last operation on the CSF shunt should receive antibiotic cover for H. influenzae.

Concentration of purine compounds in the cerebrospinal fluid of infants suffering from sepsis, convulsions and hydrocephalus

Catabolites of purine nucleotides were measured in the cerebrospinal fluid (CSF) of newborn infants with sepsis, seizures and hydrocephalus using isocratic reversed-phase HPLC. The inosine levels in the CSF of the infants with any of the illnesses were significantly higher when compared with the controls. There was a tendency for hypoxanthine levels to be higher in the group of children with hydrocephalus. No significant differences in the concentrations of xanthine, adenine and uric acid were found. The inosine concentration in the CSF is proposed to be a more sensitive indicator of brain injury than the levels of other CSF purines. The levels of all purine metabolites measured in the CSF showed large individual variations. The ratio between hypoxanthine (as an indicator of ATP breakdown) and uric acid (as a scavenger of oxygen free radicals) concentration is proposed as a new criterion to be used in the evaluation of brain injury.

Bacterial agents isolated from cerebrospinal fluid of patients with acquired immunodeficiency syndrome (AIDS) and neurological complications

Cerebrospinal fluid (CSF) samples from 2083 patients with acquired immunodeficiency syndrome (AIDS) and neurological complications were bacteriologically examined during a period of 7 years (1984-1990). The percentage of patients who had at least one bacterial agent cultured from the CSF was 6.2%. Mycobacterium tuberculosis was the most frequently isolated agent (4.3%), followed by Mycobacterium avium complex or MAC (0.7%), Pseudomonas spp (0.5%), Enterobacter spp (0.4%), and Staphylococcus aureus (0.3%). Among 130 culture positive patients, 89 (68.5%) had M. tuberculosis and 15 (11.6%) had MAC. The frequency of bacterial isolations increased from 1988 (5.2%) to 1990 (7.2%), partly due to the increase in MAC isolations. Bacterial agents were more frequently isolated from patients in the age group 21-30 years and from women (p < 0.05).

A field study of ovine bacterial meningoencephalitis

Bacterial meningoencephalitis most commonly affected lambs two to four weeks old (median three weeks, range three days to six months) with clinical signs of episcleral congestion, lack of suck reflex, weakness, altered gait and depression extending to stupor, but hyperaesthesia to auditory and tactile stimuli. Opisthotonos was observed during the agonal stages of the disease. Analysis of lumbosacral cerebrospinal fluid revealed a highly significant increase in protein concentration (P < 0.01) with a neutrophilic pleocytosis, but bacteriological culture yielded organisms in only a few cases. A response was achieved with high doses of dexamethasone and chloramphenicol in only one of 20 cases. Polyarthritis and liver abscesses in a number of lambs provided evidence of a previous bacteraemic or septicaemic episode but no definite source of the central nervous system infection was identified. In common with other infectious bacterial conditions which are prevalent during the early life of sheep, control measures should ensure an adequate transfer of passive antibody, repeated treatments of the navel, and hygienic conditions in the lambing and rearing environments.

[Clinical evaluation of biapenem (L-627), a new carbapenem antibiotic in the pediatric field]

We studied the clinical efficacy of biapenem (L-627), a new parenteral carbapenem beta-lactam antibiotic in the pediatric field. L-627 was administered intravenously to 11 patients with ages ranging 2 months to 10 years and 5 months with acute infectious diseases. Doses ranged 28.1 to 72.6 mg/kg/day. The diagnosed diseases included 7 respiratory tract infections, 1 purulent meningitis, 1 sepsis, 1 cervical lymphadenitis and 1 urinary tract infection. Two of these cases one with Mycoplasma infection and the other which had been administered with other antimicrobial agents were not evaluated. The clinical efficacy rate was 77.8% (7/9) and the bacteriological eradication rate was 66.7% (4/6). Laboratory examinations revealed that there was one case with elevated liver enzyme levels with showing elevation of GOT, GPT and LDH. No other side effects attributable to this drug were observed. Thus, it appears that L-627 is a useful antibiotic in treating moderate to severe acute bacterial infections in children.

The clinical characteristics and infectious outcomes of febrile infants aged 8 to 12 weeks

We reviewed 356 consecutive cases of febrile infants aged 8 to 12 weeks who received outpatient evaluation for sepsis over 4 years. Thirty-three infants (9.3%) had a serious bacterial infection (SBI), including bacterial meningitis, bacteremia, urinary tract infection (UTI), and Salmonella enteritis. The SBI rate, which was directly proportional to fever height, was significantly greater for infants with hyperpyrexia (35%) than those with lesser degrees of fever (7.7%) and for infants with peripheral blood leukocytosis (total WBC count > or = 15,000/mm3; 25%) than those with lesser total WBC counts (5.8%). An attending-level physician judged that 67% of infants with SBI appeared to be "well," including five or eight cases (63%) of bacteremia, 14 of 17 cases (82%) of UTI, and all three cases of Salmonella enteritis, whereas all five patients with bacterial meningitis appeared to be "ill." Urinalysis abnormalities indicative of UTI were present in 15 of 17 infants (88%) who had this infection. SBIs are not uncommon in febrile infants aged 8 to 12 weeks and occur significantly more often in those with either hyperpyrexia or peripheral blood leukocytosis.

A field study of meningoencephalitis in calves with particular reference to analysis of cerebrospinal fluid

Meningoencephalitis was recorded in 10 two- to 14-day-old calves during a two-year field study. Analysis of lumbosacral cerebrospinal fluid revealed a marked increase in protein concentration with a pronounced neutrophilic pleocytosis. Three calves with positive bacteriological cultures which were treated with chloramphenicol survived whereas six calves treated with penicillin G had to be destroyed on humane grounds after their condition deteriorated. Only two of the 10 calves had concurrent lesions of omphalophlebitis which may indicate that this is not the major route of bacterial invasion in neonatal meningoencephalitis. None of the constituents of cerebrospinal fluid proved to be a reliable prognostic indicator of meningoencephalitis. It is concluded that the analysis of cerebrospinal fluid is a useful ancillary aid in the investigation of abnormal mental states in neonatal calves and a sensitive test for the presence of an inflammatory lesion involving the leptomeninges.

Bacterial ventriculitis and duration of ventriculostomy catheter insertion

Invasive monitoring of intracranial pressure (ICP) plays an important role in managing many neurosurgical patients. While there are several techniques available to monitor ICP, the ventricular catheter is most commonly used and the most accurate. ICP monitoring poses potential risks to the patient. The most common and one of the most devastating complications is infection. This research study examined the rate of bacterial ventriculitis in relation to duration of ventricular catheter insertion as well as other factors which may contribute to ventriculitis. Data were collected prospectively on 78 patients with a ventriculostomy who were 14 years of age or older and admitted to the neuroscience intensive care unit. Patients were followed from the time of ventricular catheter placement to two weeks after the catheter was removed or until the patient was discharged from the hospital. A significantly higher ventriculitis rate was found in patients with a mean catheter duration of 11 days or longer (p = .004). In the group that developed ventriculitis there was a significant rise (means = 6.03592, p = .014) in the cerebrospinal fluid (CSF) lactate prior to the onset of ventriculitis. Neuroscience nurses should be aware of the factors which may increase the rate of ventriculitis, such as duration of catheter placement and factors which may indicate impending infection such as a rise in the CSF lactate. Future studies should compare various methods of ventriculostomy site care for efficacy of infection prevention, cost and caregiver time.

Evaluation of intraventricular teicoplanin for the treatment of neurosurgical shunt infections

Seven patients with staphylococcal neurosurgical shunt infections were treated with intraventricular teicoplanin. Two infants received 5 mg/d, three patients received 20 mg/d, and two patients received 20 mg every other day. Six of these patients also received intravenous antibiotics. Three patients had infections caused by methicillin-susceptible Staphylococcus epidermidis, and one patient had an infection caused by methicillin-resistant S. epidermidis. Three patients were infected with Staphylococcus aureus (one with a methicillin-resistant strain and two with methicillin-susceptible strains). The mean duration of intraventricular therapy was 16 days. Sterilization of cerebrospinal fluid (CSF) was obtained after an average of 4.4 days. All patients were cured both clinically and microbiologically. No significant adverse effects were observed in any patients. Penetration of teicoplanin into the CSF after intravenous administration was poor. However, after intraventricular administration, high and prolonged peak and trough levels of teicoplanin were detected in the CSF. Bactericidal activity of the CSF was remarkable, exceeding the 1:8 dilution in the majority of the cases. The alternate-day schedule of intraventricular administration of teicoplanin was as effective as the once-daily regimen.

[Mineral metabolism in bacterial meningoencephalitis]

The authors investigated the concentration of some metals in the cerebrospinal fluid in 70 patients with bacterial meningoencephalitis in the dynamics of the inflammatory process and in different regions of the brain in 10 autopsy cases. There was a correlation between potassium, sodium, manganese, magnesium, copper and zinc in the brain and quantity of water, as well as their concentration in cerebrospinal fluid. It is shown that determination of some metals in the cerebrospinal fluid allows to diagnose edema swelling of the brain and to predict the disease sequels.

Congenital bacterial sepsis in very preterm infants

The results of body fluid and surface cultures from 148 preterm infants less than 33 weeks gestational age obtained routinely on admission to a neonatal intensive care unit were reviewed. The aim was to determine the occurrence of congenital bacterial sepsis in this population and to examine whether surface cultures yielded information helpful in management. Gastric aspirate and umbilical, nasal and ear swabs were cultured and the results were compared to those of blood cultures. Nine infants (5.4%) had congenital bacterial sepsis diagnosed by positive blood cultures. Only the results of microscopy of gastric aspirate were available within hours of birth and before the results of blood culture. Microscopy of gastric aspirate, demonstrating pus cells, alone had a sensitivity of 0.86 in predicting congenital sepsis but a specificity of 0.49; the specificity, however, rose to 0.80 if both organisms and pus cells were observed on microscopy. Thus, only this combination was a useful pre-indicator of congenital sepsis. In infants who did not develop septicaemia, treatment was modified only if Streptococcus agalactiae was cultured from surface sites; in all such cases, the organism was grown from the ear swab. Our results demonstrate that congenital bacterial sepsis is common amongst very preterm infants admitted for neonatal intensive care but routine screening of surface cultures should be restricted to an ear swab only.

Outpatient treatment of febrile infants 28 to 89 days of age with intramuscular administration of ceftriaxone

STUDY OBJECTIVE

To determine the outcome of outpatient treatment of febrile infants 28 to 89 days of age with intramuscular administration of ceftriaxone.

DESIGN

Prospective consecutive cohort study.

SETTING

Urban emergency department.

PATIENTS

Five hundred three infants 28 to 89 days of age with temperatures greater than or equal to 38 degrees C who did not appear ill, had no source of fever detected on physical examination, had a peripheral leukocyte count less than 20 x 10(9) cells/L, had a cerebrospinal fluid leukocyte count less than 10 x 10(6)/L, did not have measurable urinary leukocyte esterase, and had a caretaker available by telephone. Follow-up was obtained for all but one patient (99.8%).

INTERVENTION

After blood, urine, and cerebrospinal fluid cultures had been obtained, the infants received 50 mg/kg intramuscularly administered ceftriaxone and were discharged home. The infants returned for evaluation and further intramuscular administration of ceftriaxone 24 hours later; telephone follow-up was conducted 2 and 7 days later.

RESULTS

Twenty-seven patients (5.4%) had a serious bacterial infection identified during follow-up; 476 (94.6%) did not. Of the 27 infants with serious bacterial infections, 9 (1.8%) had bacteremia (8 of these had occult bacteremia and 1 had bacteremia with a urinary tract infection), 8 (1.6%) had urinary tract infections without bacteremia, and 10 (2.0%) had bacterial gastroenteritis without bacteremia. Clinical screening criteria did not enable discrimination between infants with and those without serious bacterial infections. All infants with serious bacterial infections received an appropriate course of antimicrobial therapy and were well at follow-up. One infant had osteomyelitis diagnosed 1 week after entry into the study, received an appropriate course of intravenous antimicrobial therapy, and recovered fully.

CONCLUSIONS

After a full evaluation for sepsis, outpatient treatment of febrile infants with intramuscular administration of ceftriaxone pending culture results and adherence to a strict follow-up protocol is a successful alternative to hospital admission.