Contribution of laboratory methods in diagnosing clinically suspected ocular toxoplasmosis in Brazilian patients

This prospective study evaluated the value of laboratorial diagnosis in ocular toxoplasmosis analyzing peripheral blood samples from a group of Brazilian patients by immunologic and molecular methods. We analyzed blood samples from 184 immunocompetent patients with ocular disorders divided into 2 groups: Group I, composed of samples from 49 patients with ocular toxoplasmosis diagnosed by clinical features; Group II, samples from 135 patients with other ocular diseases. Samples were assayed by conventional polymerase chain reaction (cnPCR), real-time PCR (qPCR) for Toxoplasma gondii, indirect immunofluorescence reaction (IF), avidity test (crude tachyzoite lysate as antigen), and excreted-secreted tachyzoite proteins as antigen (ESA-ELISA). cnPCR and qPCR profiles were concordant in all samples. Positive PCR was shown in 40.8% of group I patients. The majority of the positive blood samples (75%) were taken from patients with toxoplasmic retinochoroiditis scars, and the others (25%), from patients with retinal exudative lesions. Despite that 86 of the 135 patients from Group II had asymptomatic toxoplasmosis, all DNA blood samples had negative PCR. Concordant results were shown in the data obtained by serologic methods. Around 24% of the patients with ocular toxoplasmosis had high antibody titers determined by ESA-ELISA and IF. Anti-ESA antibodies are shown principally in patients with active infection. Collectively, these data demonstrate the presence of tachyzoites in the blood of patients with chronic infection, supporting the idea of recurrent disease. Circulating parasites in blood of immunocompetent individuals may be associated with the reactivation of the ocular disease.     

Left atrial and ventricular dimensions in highly trained cyclists

Objectives: This study sought to investigate the development of left ventricular remodeling during active cycling. Methods: A group of 17-year-old (±0.2 years) highly trained competitive cyclists (group I, n = 66) and a group of 29-year old (± 2.6 years) professional cyclists (group II, n = 35) underwent two-dimensional (2D) echocardiography. Data from groups I and II were compared with values of normal untrained subjects based on the literature. Results: Left atrial dimensions were significantly increased in group II as compared to group I (44 ± 5 vs. 36 ± 4 mm, p < 0.005). Left ventricular end diastolic diameter was significantly increased in group II as compared to group I (61 ± 5 vs. 54 ± 6 mm, p < 0.005). Left ventricular mass was also significantly increased in group II as compared to group I (321 ± 77 vs. 246 ± 59 g, p < 0.005). Wall stress showed a significant inverse relation: 104 ± 42 mmHg in group I vs. 83 ± 14 mmHg in group II (p < 0.005). The early filling phase of the left ventricular inflow was significantly larger in both athlete groups in relation to the normal value. The E-wave in the athletes compared to the E-wave in normal subjects was 0.87 ± 0.17 vs. 0.71 ± 0.14 m/s in group I, p < 0.005, 0.82 ± 0.17 vs. 0.71 ± 0.14 m/s in group II, p < 0.05. Late filling phase and the ratio of the diastolic filling pattern did not show significant differences between the two groups. Conclusions: Left atrial and left ventricular remodeling starts early in the athlete's career. Athletes of 17 years of age already show significant left atrial and left ventricular dilatation compared to data of untrained subjects described in literature. The process of dilatation continues during the athlete's career. Also left ventricular mass is increased at a young age which continues for several years. More than 60% of the athletes in both groups demonstrated an intermediate form of left ventricular hypertrophy. Diastolic function of the left ventricle remains normal during a long period of athletic career performance.     

Angiocardiographic Pressure Volume Loops in the Analysis of Right Ventricular Function after Repair of Tetralogy of Fallot

Objective: The objective of the study was to estimate the capacity of pressure volume (PV) loop analysis to assess right ventricular (RV) function after Fallot (TOF) repair.Patients: Fifty six patients were examined after TOF repair. PV loops were constructed from RV angiocardiography and simultaneous pressure measurement. Patients were divided in three groups according to RV size and pressure (Group I: normal RV size and pressure; group II: enlarged RV, near normal pressure; group III: normal RV size, elevated pressure).Main outcome measures: Systolic stroke work corrected for body surface area (W/BSA) and for RV enddiastolic volume (W/EDV), peak RV filling (PFR) and emptying rates (PER) corrected for RV stroke volume, cycle efficiency (CE), RV ejection fraction (RVEF).Results: W/BSA was significantly higher in group II than in group I (0.19 ± 0.05 vs. 0.11 ± 0.04 J/m², p < 0.001) and was similar between groups II and III (0.19 ± 0.05 vs. 0.17 ± 0.05 J/m² ; NS). W/EDV was similar in groups I and II (12.4 ± 5.4 vs. 12.4 ± 2.9 mmHg; NS). CE was smallest in group II. The difference was significant between groups II and III (0.62 ± 0.08 vs. 0.73 ± 0.09; p < 0.05). RVEF was negatively correlated to RV end systolic volume (RVESV) in the patients of groups I and II (r = −0.32, p < 0.05). A similar correlation was found between PFR and RVESV (r = −0.28, p < 0.05).Conclusions: Analysis of a single PV loop allows quantification of RV load after TOF repair. W/BSA is increased to the same extent under volume and pressure load. The lack of decrease in W/EDV in patients with enlarged RV indicates that RV is capable to perform adequate work in a wide range. RVESV is a useful measure for estimating RV function after TOF repair depicting parameters of systolic and diastolic RV function.     

Oral nystatin prophylaxis of Candida spp. colonization in ventilated critically ill patients

Objective Colonization of multiple body sites is a leading risk factor for Candida spp. infection in intensive care unit (ICU) patients. We evaluated whether oral nystatin prophylaxis reduces Candida spp. colonization in ventilated ICU patients.Design and setting Prospective, randomized, open-label study with blinded assessment of the objective primary evaluation criterion in the medical-surgical ICU of a teaching hospital.Patients The study included 98 consecutive patients mechanically ventilated for at least 48 h (mean age 58±19 years; mean SAPS II 40±11), assigned to either treatment group (n=51) or control group (n=47). Study groups were comparable for age, SAPS II, reason for admission, and immune status.Interventions Patients were randomized to receive oral nystatin (treatment group; 3×10⁶ U per day) or no nystatin (control group). Multiple body sites (trachea, stomach, rectum, urine, groin, and blood) were tested for Candida spp. on admission and then every 3 days by mycologists blinded to group assignment, and the colonization index was determined.Results Colonization by Candida spp. developed in 25% of controls but in none of the treated patients. In multivariate analysis, the absence of nystatin prophylaxis and ICU length of stay were independently associated with Candida spp. colonization. No invasive candidiasis was diagnosed in either study group.Conclusions Oral nystatin prophylaxis efficiently prevented Candida spp. colonization in ICU patients at low risk of developing invasive candidiasis. Further studies are needed to determine whether this strategy remains efficient in reducing Candida spp. infections in higher risk ICU patients.This article is discussed in the editorial available at:     

Effects of positive end-expiratory pressure on hyaline membrane formation in a rabbit model of the neonatal respiratory distress syndrome

Sixteen rabbits were anaesthetized and subjected to saline lavage of the lungs to produce surfactant deficiency. This resulted in an arterial oxygen tension of less than 12 kPa on 100% inspired oxygen and an inflection point on the pressure-volume curve at a pressure of 8–12 mmHg. After lavage the animals were randomly assigned to receive either conventional mechanical ventilation (CMV) with a positive end-expiratory pressure (PEEP) of 1–2 mmHg (group I —low PEEP) or CMV with PEEP equal to the inflection point pressure (group II — high PEEP). Mean airway pressures were kept at 14–16 mmHg in both groups by increasing the inspiratory: expiratory time ratios in the low PEEP group. The 5-h protocol was completed by 4 animals in group I and 6 animals in group II, early death usually being associated with a metabolic acidosis. On 100% oxygen, the mean PaO₂ at 2-h post-lavage was 15.2±8.3 kPa in group I and 39.6±21.8 kPa in group II. Group I had much lower end-expiratory lung volumes (3.0±1.5 ml above FRC) than group II (34.9±12.2 ml above FRC). Histological examination of the lungs revealed significantly less hyaline membrane formation in group II (p=0.001). Thus, the prevention of alveolar collapse by the use of high PEEP levels appears to reduce lung damage in this preparation.     

Measurement of aortic blood velocity in acute myocardial infarction by Doppler ultrasound

Aortic blood velocity was measured by a transcutaneous continuous wave Doppler technique in thirty-five patients with proven acute myocardial infarction. Measurements were made on the first and seventh day following admission to hospital. Group I comprised 21 patients who had sustained a first myocardial infarction of moderate size, uncomplicated by hypoperfusion. Group II comprised 14 patients who had had a large rise in cardiac enzymes, a previous myocardial infarction or were clinically hypoperfused. The mean value for peak aortic velocity for Group I on Day 1 was 88±12.9 cm/s. This was significantly lower than the mean value of 101.8±23.1 cm/s for a group of 85 normal subjects. By Day 7 the mean value for Group I of 105.1±19.8 cm/s was not significantly different from normal. For Group II patients on Day 1 the mean value for peak aortic velocity was 67.9±11.7 cm/s and was significantly lower than that for both Group I and the normal group. By the seventh day the mean value for Group II was 76.5±17.1 cm/s which was not significantly different from Day 1.     

Continuous gastric suctioning decreases measured esophageal temperature during general anesthesia

Objective. This study sought to determine whether continuous gastric suctioning influences esophageal temperature measurements.Methods. This study evaluated 21 patients scheduled for extremity or lower abdominal surgery. After induction of general endotracheal anesthesia, an orogastric tube, and esophageal and nasopharyngeal temperature probes were placed in functional positions. Baseline esophageal (Tes) and nasopharyngeal (Tnas) temperatures were recorded and the orogastric tube was placed on continuous suction. After the first 11 patients (Group I) were studied, 10 additional patients (Group II) were studied with more frequent data collection to improve the time resolution of temperature changes. Temperatures were recorded for patients in Group I at 2 and 10 min with suctioning and 10 min after cessation of suctioning. In Group II, temperatures were recorded at 1, 2, 5 and 10 min with suctioning and 10 min after cessation of suctioning. Analysis of data was performed using repeated measures analysis of variance and pairedt-tests with the Bonferroni correction.Results. In Group I, Tes decreased significantly from 35.9 ± 0.2 °C (mean ± SE) to 35.1 ± 0.4 °C at 2 min and 34.8 ± 0.3 °C at 10 min of suctioning (p < 0.01). Ten minutes after cessation of suctioning, Tes was not significantly different from the baseline measurement. Tnas did not change significantly over the 20 min observation period. In Group II, Tes continually decreased from 36.2 ± 0.1 °C to 34.8 ± 0.3 °C after 10 min of suctioning (p < 0.006) and returned to near baseline 10 min after cessation of suctioning. There was no significant change in Tnas over the 20 min observation period.Conclusion. We conclude that continuous gastric suctioning decreases esophageal temperature measurements. This phenomenon should be recognized as an artifactual change in esophageal temperature and not a reflection of core temperature.This study was presented, in part, at the 1995 Annual Meeting of the American Society of Anesthesiologists, Atlants, GA, October 1995.     

Safety and efficacy of colistin in Acinetobacter and Pseudomonas infections: a prospective cohort study

Objective To assess renal dysfunction and outcome in patients treated exclusively with colistin vs. other antibiotics.Design and setting Prospective cohort study in a mixed ICU in a university-affiliated hospital.Patients 185 patients infected with Acinetobacter baumannii and Pseudomonas aeruginosa after an ICU stay longer than 48 h: 55 in the colistin group and 130 in the noncolistin group, similar in age, APACHE II, medical status, and SOFA score.Measurements and results We recorded data on epidemiology and severity of illness, site of infection, renal function before and after treatment, clinical cure, and mortality. Clinical cure was defined as simultaneous normalization of central temperature (38°), leukocyte count (10,000/mm³), and PaO₂/FIO₂ ratio (>187). Before treatment creatinine was 0.9±0.2 in the colistin group and 0.9±0.1 in the noncolistin group; after treatment the value was 1.0±0.3 in both groups. The most frequent infection was ventilator-associated pneumonia: 53% vs. 66% in colistin and noncolistin groups, respectively, Acinetobacter was the cause in 65% and 60% and Pseudomonas in 35% and 53%. In the noncolistin group 81% of patients were treated with carbapenems. Inadequate empirical antimicrobial treatment was more frequent in the colistin group (100% vs. 8%), but there were no differences in the frequency of clinical cure on day 6 of treatment (15% and 17%) or in mortality (29% and 24%).Conclusions Colistin appears to be as safe and as effective as other antimicrobials for treatment of sepsis caused by Acinetobacter and Pseudomonas in critically ill patients.     

Cerebrospinal fluid lactate dehydrogenase as a potential predictor of neurologic outcomes in cardiac arrest survivors who underwent target temperature management

PurposeCerebrospinal fluid (CSF) lactate dehydrogenase (LDH) levels increase in patients with brain injury. We investigated neurologic outcomes associated with CSF LDH levels in out-of-hospital cardiac arrest (OHCA) survivors who underwent target temperature management (TTM).Materials and methodsThis was a prospective single-centre observational study from April 2018 to May 2019 on a cohort of 41 patients. CSF and serum LDH samples were obtained immediately (LDH₀) and at 24 (LDH₂₄), 48 (LDH₄₈), and 72 h (LDH₇₂) after return of spontaneous circulation (ROSC). Neurologic outcomes were assessed at 3 months after ROSC using the Cerebral Performance Category scale.ResultsTwenty-one patients had a poor neurologic outcome. CSF LDH levels were significantly higher in the poor neurologic outcome group at each time point. The area under the curve (AUC) of CSF LDH₄₈ was 0.941 (95% confidence interval [CI], 0.806–0.992). With a cut off value of 250 U/L, CSF LDH₄₈ had a high sensitivity (94.1%; 95% CI, 71.3–99.9) at 100% specificity.ConclusionsCSF LDH level at 48 h was a highly specific and sensitive marker for 3-month poor neurologic outcome. This may constitute a useful predictive marker for neurologic outcome in OHCA survivors treated with TTM.     

Correlation between neurotrophic factor expression and outcome of children with severe traumatic brain injury

Objectives We evaluated the neurotrophic factors [nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), glia-derived neurotrophic factor (GDNF)] expression and their association with the severity and outcome of children with traumatic brain injury.Design Prospective observational clinical study.Setting Pediatric intensive care unit.Patients Fourteen children with severe head injury; 12 controls with obstructive hydrocephalus.Measurement Cerebrospinal fluid (CSF) and plasma samples were collected 2 h (T1) and 24 h (T2) after head injury. Neurotrophic factor levels were measured using an immuno-enzymatic assay.Main results In patients, neurotrophic factor mean levels were significantly different in both CSF and plasma, showing high levels of BDNF compared to NGF and GDNF. Considering T1 and T2 expression, in the CSF the level of NGF increased from 3.5±0.4 pg/ml to 48.2±11.7 pg/ml (p<0.001); BDNF decreased from 4854.0±1303.7 pg/ml to 593.0±114.8 pg/ml (p<0.001), while GDNF did not undergo significant variations. In plasma, no significant changes were observed. Regarding severity and outcome, BDNF levels showed a sharp peak after head injury, but the only significant association was between NGF expression in the CSF and a good outcome versus a poor outcome (p=0.007).Conclusions The variations in neurotrophic factor levels reflect an endogenous attempt at neuroprotection against biochemical and molecular changes after traumatic head injury. BDNF represents an early marker of brain injury, while NGF expression in the CSF was indicative of a good outcome and the role of this neurotrophin in the treatment of children with severe head injury may be hypothesized.     

Diazepam does not improve the mechanical performance of rat cardiac papillary muscle exposed to chloroquine in vitro

Diazepam has been reported to decrease the cardiac toxicity of chloroquine but the precise mechanism involved remains unknown. Left ventricular papillary muscles from adult Wistar rats were exposed to 10^-4 M chloroquine and assigned to three groups: group I (n=10) exposed to chloroquine alone; group II (n=8) exposed to chloroquine and 10^-5 M diazepam; group III (n=8) exposed to chloroquine and 10^-4 M diazepam. The main mechanical parameters measured were: maximum unloaded shortening velocity (Vmax), maximum lengthening velocity (maxVr), active force normalized per cross-sectional area (AF/s), contraction-relaxation coupling under low load (R1), load sensitivity of relaxation (Isot.A/ Isom.A), and peak power output ( max) determined from Hill's equation of the force-velocity curve. Data are expressed as mean percent of control values±SD, for groups I, II, III respectively. No differences between groups I, II, and III were noted for Vmax (87±13, 82±9, 86±7), maxVr (47±6, 48±11, 52±11), AF/s (87±16, 91±10, 83±11), Isot. A/Isom. A (113±9, 108±3, 109±7), or max (75±10, 81±12, 72±16). Chloroquine was shown to be a negative inotropic agent since it decreased Vmax, AF/s and max, but diazepam did not restore the intrinsic mechanical performance of rat cardiac papillary muscle exposed to chloroquine, therefore 1) the protective cardiovascular effects of diazepam in chloroquine poisoning are not related to an improvement in intrinsic cardiac mechanical properties; 2) inotropic agents are therefore necessary in combination with diazepam for the treatment of severe chloroquine poisoning.B. Riou was a recipient of a fellowship grant from the Fondation pour la Recherche Médicale. This study was presented in part at the FASEB Annual Meeting, May 1–5, 1988, Las Vegas, Nevada, USA     

Autonomic control of the heart and peripheral vessels in human septic shock

Objective Circulating endotoxin impairs the sympathetic regulation of the cardiovascular system in animals. We studied the changes in the autonomic control of the heart and circulation during septic shock in humans.Design 12 patients (age 43.0±6, 17–83 years) were investigated during septic shock (mean duration: 3.5±0.5 days) and during recovery, fluctuations in R-R interval, invasive arterial pressure (AP) and peripheral arteriolar circulation (PC, photoplethysmography) were evaluated by spectral analysis as a validated nonivasive measure of sympathovagal tone. Apache II score was adopted as the disease severity index. Low frequency components (0.03–0.15 Hz) of the frequency spectra were expressed as relative to the overall variability (LFnu) for each cardiovascular variable.Results LFnu were low or absent during shock but, in the 10 patients who recovered, increased by the time of discharge (post-shock). R-R LFnu increased from 17±6 to 47±9 (p<0.03), AP LFnu from 6±3 to 35±4 (p<0.02) and PC LFnu from 18±3 to 66±4 (p<0.001). Apache II fell from 23.1±1, at admission, to 14.8±1.8 at discharge (p<0.005). Two patients died showing no LFnu increase.Conclusion Reduced LF components of the variability of cardiovascular signals are characteristic of septic shock, confirming the presence of abnormal autonomic control. Restored sympathetic (LF) modulation seems to be associated with a favourable prognosis.     

Combination treatment with 17β-estradiol and therapeutic hypothermia for transient global cerebral ischemia in rats

Objective

Therapeutic hypothermia is now regarded as the only effective treatment of global ischemic injury after cardiac arrest. Numerous studies of the neuroprotective effects of 17β-estradiol have yielded conflicting results depending on administration route and dose. Herein, we investigated the neuroprotective effect of postischemic 17β-estradiol administration combined with therapeutic hypothermia.

Methods

Twenty-one rats were randomly divided into 4 groups: control (group I), therapeutic hypothermia (group II), 17β-estradiol treatment (group III), and therapeutic hypothermia combined with 17β-estradiol treatment (group IV). One rat was assigned to a sham operation group. With the exception of the sham-operated rat, all animals underwent transient global cerebral ischemia for 20 minutes by the 4-vessel occlusion method. Hypothermia was maintained at 33°C for 2 hours in groups II and IV, and 17β-estradiol (10 μg/kg) was intraperitoneally administered to rats in groups III and IV. Neurologic deficit scores and hippocampal cornu ammonis 1 neuronal injury were assessed 72 hours postischemia.

Results

The neurologic deficit score was not significantly different among the groups. The percentage of normal neurons in the hippocampal cornu ammonis 1 was 7.32% ± 0.88% in group I, 53.65% ± 2.52% in group II, 51.6% ± 3.44% in group III, and 79.79% ± 1.6% in group IV. The neuroprotective effect in the combined treatment group was markedly greater than in the single treatment groups, which suggests that hypothermia and 17β-estradiol work synergistically to exert neuroprotection.

Conclusion

Postischemic administration of low-dose 17β-estradiol appears to be neuroprotective after transient global ischemia, and its effect is potentiated by therapeutic hypothermia.     

Serum selenium and zinc levels in critically ill surgical patients

Purpose

The authors designed this study to determine how serum selenium and zinc affect the outcomes of critically ill surgical patients.

Methods

The medical records of 162 patients admitted to a surgical intensive care unit (ICU) from October 2010 to July 2012 and managed for more than 3 days were retrospectively investigated.

Results

Overall, the mean patient age was 61.2 ± 15.0 years, and the median ICU stay was 5 (3-115) days. The mean Acute Physiologic and Chronic Health Evaluation II score was 18.0 ± 8.0. Eighteen (11.1%) of the study subjects died in ICU. mean selenium levels were 83.5 ± 23.8 ng/dL in the survivor group and 83.3 ± 29.6 ng/dL in the nonsurvivor group, and corresponding mean zinc levels were 46.3 ± 21.7 and 65.6 ± 41.6 μg/dL, respectively. Mean selenium concentrations were significantly different in patients with and without shock (77.9 ± 25.4 and 87.2 ± 23.1 ng/dL, P = .017). Furthermore, mean serum selenium was lower in patients with sepsis than in traumatic or simply postoperative patients (P < .001 and P = .038). Serum Zn was significantly lower in patients with sepsis than in patients with trauma (43.4 ± 25.4 μg/dL vs 54.8 ± 28.1 μg/dL, P = .038).

Conclusions

To determine the effects of serum selenium and zinc levels on critically ill surgical patients, a large-scale prospective study is needed.     

Measurement of the Intimal Thickness of the Carotid Artery: Comparison Between 40 MHz Ultrasound and Histology in Rats

Common carotid artery intimal thickness (IT) has been shown to be as useful as a measurement of the whole layer of intima-media thickness (IMT) for evaluating the early phase of atherosclerosis. The aim of this study was to elucidate the relationship between high echogenic intimal thickening (HEIT), which was measured using a 40 MHz ultrasound biomicroscope (UBM), and the histologically determined IT in rat carotid arteries. HEIT was estimated in 10 Wistar-Kyoto rats (group I), 15 spontaneous hypertensive rats (SHR) fed a standard diet (group II) and 10 SHR fed a high-fat diet (group III). IT and IMT measurements were determined in Masson trichrome-stained tissues and were compared with the HEIT and IMT evaluated using the UBM. In group I, the HEIT and the IT were 33 ± 4 μm and 12 ± 1 μm, respectively. In group II, the HEIT and the IT were 68 ± 8 μm and 16 ± 2 μm, respectively. In group III, the HEIT and the IT were 65 ± 26 μm and 33 ± 14 μm, respectively. In SHR, the HEIT and the mean IMT measured with echography were significantly correlated with the IT and the IMT that were determined by histologic measurement (r = 0.60, p = 0.003 and r = 0.53, p = 0.01, respectively). Moreover, HEIT may be associated with the intimal pathology and atherosclerotic burden. The HEIT measurement is a noninvasive method that may be used to assess atherosclerosis in humans. (E-mail:younhj@catholic.ac.kr)     

Serodiagnosis of Chlamydia pneumoniae infection using three inclusion membrane proteins

The Chlamydia pneumoniae genome‐encoded open reading frames Cpn0146, Cpn0147, and Cpn0308 were expressed as recombinant proteins for detecting C. pneumoniae‐specific antibodies in samples from three groups of individuals including 183 with C. pneumoniae‐associated respiratory infection (group I), 60 healthy blood donors (group II), and 32 with no known respiratory infection (group III). The recombinant Cpn0146 was recognized by 71 (38.8% positive recognition rate), 15 (25%) and 1 (3.1%), Cpn0147 by 75 (40.9%), 14 (23.3%), and 2 (6.3%), and Cpn0308 by 82 (44.8%), 16 (26.7%), and 0 (0%) samples from groups I, II, and III, respectively. The positive recognition rates with any of the three antigens were significantly higher in group I than those in groups II and III, suggesting that more individuals from group I were likely infected with C. pneumoniae. This conclusion was confirmed with a commercially available whole organism‐based ELISA kit (Savyon Diagnostics Ltd., Ashdod, Israel), which detected C. pneumoniae antibodies in 98 (64.1%), 26 (43.3%), and 4 (12.5%) samples from group I, II, and III, respectively. Comparing to the commercial kit, the recombinant antigen‐based detection assays displayed >97% of detection specificity and >87% of sensitivity, suggesting that these recombinant antigens can be considered alternative tools for aiding in serodiagnosis of C. pneumoniae infection. J. Clin. Lab. Anal. 24:55–61, 2010. © 2010 Wiley‐Liss, Inc.     

Usefulness of interleukin 6 levels in the cerebrospinal fluid for the diagnosis of bacterial meningitis

Purpose

Interleukin 6 (IL-6) is a proinflammatory cytokine produced during infections. We hypothesized that IL-6 levels in the cerebrospinal fluid (CSF) would be elevated in bacterial meningitis and useful for diagnosing and predicting neurologic outcomes.

Materials and methods

For the differentiation of bacterial meningitis, serum and CSF samples were obtained from patients with an altered level of consciousness. Patients were classified into 3 groups: bacterial meningitis, nonbacterial central nervous system disease, and other site sepsis.

Results

Of the 70 patients included in this study, there were 13 in the bacterial meningitis group, 21 in the nonbacterial central nervous system disease group, and 36 in the other site sepsis group. The CSF IL-6 level was significantly higher in the bacterial meningitis group than in the other 2 groups (P < .0001). Of the 5 CSF parameters assessed, CSF IL-6 level exhibited the largest area under the receiver operating characteristic curve (0.962), with a cut-off value of 644 pg/mL (sensitivity, 92.3%; specificity, 89.5%). To examine a potential association between a high CSF level and neurologic outcome, CSF IL-6 levels were divided into 4 quartiles, and each level was compared with the frequency of a good neurologic outcome. The frequency of a good neurologic outcome was significantly lower in the highest CSF IL-6 quartile than in the other 3 quartiles (odds ratio, 0.18; 95% confidence interval, 0.05-0.69; P = .013).

Conclusions

Measurement of the CSF IL-6 level is useful for diagnosing bacterial meningitis.     

Clinical consequences of the implementation of a weaning protocol

Objective To analyze the clinical and economic consequences of the implementation of a weaning protocol in patients mechanically ventilated (MV) for more than 48 h.Design Comparative studySetting General intensive care unit (ICU) in a county hospital covering 360 000 inhabitants.Patients 51 patients weaned by a fixed protocol were studied prospectively and compared with 50 retrospective controls.Measurements The following variables were assessed: Acute Physiology and Chronic Health Evaluation (APACHE) II score, age, cause of respiratory failure, type of extubation (direct extubation or extubation using a weaning technique), number of days on MV before the weaning trial, weaning time, total duration of MV, complications (reintubations and tracheostomies), length of ICU stay, and mortality.Results The groups were comparble in terms of age, APACHE II score, and main cause of acute respiratory failure. Number of days on MV up to the weaning trial were similar in the two groups (8.4±7.7 in the protocol group vs 7.5±5.5 in the control group, NS). Most of the patients (80%) in the protocol group were directly extubated without a weaning technique, unlike the control group (10%) (p<0.01). When a weaning technique was used, the weaning time was similar in both groups (3.5±3.9 days vs 3.6±2.2 days in the control group). Duration of MV was shorter in the protocol group (10.4±11.6 days) than in the control group (14.4±10.3 days) (p<0.05). As a result, the ICU stay was reduced by using the weaning protocol (16.7±16.5 days vs 20.3±13.2 days in the control group,p<0.05). We found no differences in reintubation rate (17 vs 14% in the control group) and need for tracheostomies (2 vs 8% in the control group).Conclusion The implementation of a weaning protocol decreased the duration of MV and ICU stay by increasing the number of safe, direct extubations.Supported in part by grant FIS 93/0590     

Adrenocortical function: An indicator of severity of disease and survival in chronic critically ill patients

Plasma cortisol levels and modified Apache II (Apache IIm-stay) severity of disease scores were determined at weekly intervals in 159 patients who were treated for at least 7 days at the Critical Care Unit of our hospital. The mean (±SD) plasma cortisol level (0.60±0.28 mol/l) was clearly elevated in these patients. The highest plasma cortisol levels were measured in patients treated with vasoactive drugs (0.76±0.39 mol/l). Non-survivors (n=36) had a significantly higher mean plasma cortisol level and Apache IIm-stay score than survivors (respectively 0.78±0.40 vs. 0.54±0.21 mol/l;p<0.0003 and 12.6±4.8 vs. 7.3±4.1;p<0.0001). A significant correlation was found between the individual weekly plasma cortisol levels and the Apache IIm-stay scores (r=0.41;p<0.0001), especially in the subgroup of patients, who never received glucocorticoids during their stay at the ICU (r=0.51;p<0.0001). During the 14-month study period only two patients showed a clinical picture of adrenocortical insufficiency and a blunted response of cortisol to 0.25 mg synthetic ACTH(1-24). In conclusion, our data suggest that a high plasma cortisol level, like a high Apache IIm-stay score, indicates severity of disease and poor survival in critically ill patients. De novo adrenocortical insufficiency is rare and therefore routine screening of adrenocortical function is superfluous.     

Assessment of TLR-2 concentration in tick-borne encephalitis and neuroborreliosis

Abstract

The aim of the study was to check whether measurement of TLR-2 in serum or cerebrospinal fluid (CSF) can help differentiate between neuroborreliosis (NB) and tick-borne encephalitis (TBE). Eighty patients with meningitis and meningoencephalitis were divided into two groups: Group I – patients with NB (n?=?40) and Group II – patients with TBE (n?=?40). Diagnosis was based on the clinical picture, CSF examination and presence of specific antibodies in serum and CSF. The control group (CG) consisted of healthy blood donors (n?=?25) and patients in whom inflammatory process in central nervous system was excluded (n?=?25). Concentration of TLR-2 was measured using a commercial kit [TLR-2 Elisa Kit (EIAab, China)]. The serum and CSF TLR-2 concentration of NB patients was significantly higher than in CG. The serum and CSF TLR-2 concentration in TBE patients was significantly higher than in the CG. Receiver operating characteristic analysis of the serum TLR-2 concentration showed significant differences between the group of patients with NB and a group of patients with TBE. TLR-2 is involved in the development of inflammatory process in the CNS caused by both tick-borne pathogens: viral and bacterial as TLR-2 concentration in both CSF and serum differentiates these groups from healthy patients. Although TLR-2 cannot be used as a sole and reliable biomarker differentiating NB from TBE, results of our study are a step forward toward discovering such biomarker in the future.