PROCALCITONIN MIGHT HELP IN DISCRIMINATION BETWEEN MENINGEAL NEURO-BEHcET DISEASE AND BACTERIAL MENINGITIS

Neuro-Behçet Disease, Neuro-Sweet Disease, and Spectrum Disorders

Behçet disease and its related disorder, Sweet disease, are multifactorial disorders whose susceptibility loci have been identified in the genes of various immunological factors aside from human leukocyte antigens. The neurological involvement of these diseases, including encephalitis, myelitis, and meningitis, referred to as neuro-Behçet disease (NBD) and neuro-Sweet disease (NSD) respectively, is sometimes difficult to diagnose, especially when the characteristic mucocutaneous symptoms do not precede neurological symptoms or when characteristics of both diseases are present in a single patient. NBD and NSD constitute a spectrum of diseases that are differentiated according to the combination of risk factors, including the genetic background. Encephalitis, myelitis, and meningitis similar to NBD or NSD can be diagnosed as spectrum disorders, even if the characteristic mucocutaneous symptoms fail to be detected. Understanding these conditions as a disease spectrum may help elucidate the disease pathogenesis and assist in the development of therapeutic agents.

Procalcitonin levels among patients with fever secondary to severe intracerebral infection. A cross-sectional study

BACKGROUND

Making the differential diagnosis between central fever and infectious fever is critically important among intracerebral hemorrhage patients followed up in intensive care units (ICUs). Serum procalcitonin (PCT) has been found to be a promising biomarker for the initial diagnosis of infection, even before culturing results.

OBJECTIVES

To investigate the relationship between PCT and both fever etiologies and C-reactive protein (CRP) levels among critically ill patients with suspected intracerebral hemorrhage.

DESIGN AND SETTING

Cross-sectional study in a public university hospital in Elazig, Turkey.

METHODS

ICU patients diagnosed with intracerebral hemorrhage and normal procalcitonin levels were included in this study. From clinical assessments and cultures, they were classified as presenting either infectious or central fever. The sensitivity and specificity of PCT and CRP for predicting infection were calculated using a receiver operating characteristic (ROC) curve.

RESULTS

There were 98 ICU patients with diagnoses of intracerebral hemorrhage. The median (interquartile range) PCT levels of patients with infectious and central fever were 4 (0.9-11) and 0.1 (0.1-0.4) ng/ml, respectively, with a statistically significant intergroup difference (P < 0.001). The areas under the ROC curve for predicting infectious or central fever PCT and CRP were 0.958 (P < 0.001) and 0.816 (P < 0.001), respectively. A statistically significant positive correlation was detected between PCT and CRP levels in patients with infectious fever (rho: 0.461; P = 0.003), but not in patients with central fever.

CONCLUSIONS

PCT can possibly be used as a biomarker to differentiate between infectious and central fever among ICU patients.

[The etiology, diagnosis, and treatment of neurological complications in Behçet disease and its related disorder Sweet disease]

Behçet disease, and its related disorder Sweet disease, are multisystem inflammatory conditions characterized by muco-cutaneous symptoms. When neuropsychiatric symptoms appear, the two conditions are referred to as neuro-Behçet disease and neuro-Sweet disease. While diagnosing these conditions according to their diagnostic criteria, muco-cutaneous symptoms must be observed; however, neuropsychiatric symptoms may precede muco-cutaneous symptoms. In these conditions the dysregulation of cytokines, following the onset of oral muco-cutaneous bacterial infection, may induce an abnormal chemotaxis of neutrophils causing ectopic encephalitis and meningitis. Thus, an initial treatment targeting neutrophils should be considered based on the diagnosis of neuro-neutrophilic disease when symptoms indicating neutrophil hyperactivity are observed, even without muco-cutaneous symptoms. In addition to human leukocyte antigen-B51 and -A26, genome-wide association analyses have identified new susceptibility loci on the genes of various immunological factors in Behçet disease. These findings may help elucidate disease pathogenesis and assist the development of diagnostic modalities and therapeutic agents for neuro-neutrophilic disease.

MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 1: Frequency, syndrome specificity, influence of disease activity, long-term course, association with AQP4-IgG, and origin

Background

Antibodies to myelin oligodendrocyte glycoprotein (MOG-IgG) have been suggested to play a role in a subset of patients with neuromyelitis optica and related disorders.

Objective

To assess (i) the frequency of MOG-IgG in a large and predominantly Caucasian cohort of patients with optic neuritis (ON) and/or myelitis; (ii) the frequency of MOG-IgG among AQP4-IgG-positive patients and vice versa; (iii) the origin and frequency of MOG-IgG in the cerebrospinal fluid (CSF); (iv) the presence of MOG-IgG at disease onset; and (v) the influence of disease activity and treatment status on MOG-IgG titers.

Methods

614 serum samples from patients with ON and/or myelitis and from controls, including 92 follow-up samples from 55 subjects, and 18 CSF samples were tested for MOG-IgG using a live cell-based assay (CBA) employing full-length human MOG-transfected HEK293A cells.

Results

MOG-IgG was detected in 95 sera from 50 patients with ON and/or myelitis, including 22/54 (40.7 %) patients with a history of both ON and myelitis, 22/103 (21.4 %) with a history of ON but no myelitis and 6/45 (13.3 %) with a history of longitudinally extensive transverse myelitis but no ON, and in 1 control patient with encephalitis and a connective tissue disorder, all of whom were negative for AQP4-IgG. MOG-IgG was absent in 221 further controls, including 83 patients with AQP4-IgG-seropositive neuromyelitis optica spectrum disorders and 85 with multiple sclerosis (MS). MOG-IgG was found in 12/18 (67 %) CSF samples from MOG-IgG-seropositive patients; the MOG-IgG-specific antibody index was negative in all cases, indicating a predominantly peripheral origin of CSF MOG-IgG. Serum and CSF MOG-IgG belonged to the complement-activating IgG1 subclass. MOG-IgG was present already at disease onset. The antibodies remained detectable in 40/45 (89 %) follow-up samples obtained over a median period of 16.5 months (range 0–123). Serum titers were higher during attacks than during remission (p < 0.0001), highest during attacks of simultaneous myelitis and ON, lowest during acute isolated ON, and declined following treatment.

Conclusions

To date, this is the largest cohort studied for IgG to human full-length MOG by means of an up-to-date CBA. MOG-IgG is present in a substantial subset of patients with ON and/or myelitis, but not in classical MS. Co-existence of MOG-IgG and AQP4-IgG is highly uncommon. CSF MOG-IgG is of extrathecal origin. Serum MOG-IgG is present already at disease onset and remains detectable in the long-term course. Serum titers depend on disease activity and treatment status.

The role of serum procalcitonin in the diagnosis of bacterial meningitis in adults: a systematic review and meta-analysis

OBJECTIVE

Clinically, it is often difficult to differentiate between bacterial and viral aetiologies in adults with suspected meningitis. Several studies have demonstrated the potential use of serum procalcitonin (PCT) in making this differentiation. The aim was to pool these studies into a meta-analysis to determine the diagnostic accuracy of PCT.

METHODS

Major electronic databases were searched for articles studying the use of serum PCT in the differentiation of bacterial and viral meningitis in adult patients. No date or language restrictions were applied. Data analysis was performed using Meta-DiSc 1.4 and MIX 2.0.

RESULTS

Nine studies (n=725 patients) were included in the meta-analysis. Serum PCT was found to be a highly accurate test for diagnosing meningitis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio (DOR) for PCT were 0.90 (95% confidence interval (CI) 0.84-0.94), 0.98 (95% CI 0.97-0.99), 27.3 (95% CI 8.2-91.1), 0.13 (95% CI 0.07-0.26), and 287.0 (95% CI 58.5-1409.0), respectively. PCT was found to be far superior to C-reactive protein, which had a pooled DOR of only 22.1 (95% CI 12.7-38.3).

CONCLUSIONS

Serum PCT is a highly accurate diagnostic test that can be used by physicians for rapid differentiation between bacterial and viral causes of meningitis in adults.

The utility of serum procalcitonin in distinguishing systemic inflammatory response syndrome from infection after aneurysmal subarachnoid hemorrhage

BACKGROUND

Systemic inflammatory response syndrome (SIRS) occurs frequently after aneurysmal subarachnoid hemorrhage (aSAH). It is a clinical challenge to distinguish between SIRS and incipient infection. Procalcitonin (PCT) has been studied among general critical care patients as a biomarker for infection. We hypothesized that PCT could be useful to distinguish SIRS from sepsis in aSAH patients.

METHODS

Prospective, observational study conducted in the multidisciplinary intensive care unit at Mayo Clinic, Jacksonville, FL between August 2009 and September 2010. Main predictor was serum PCT obtained on admission and with subsequent episodes of SIRS. A level of 0.2 ng/mL or higher was considered as elevated PCT. Main outcome was clinical infection, which was subsequently subcategorized into major (systemic) and minor (localized) infections in the sensitivity analysis.

RESULTS

Forty consecutive patients were enrolled. Majority (88 %) developed SIRS during the hospitalization. Infection developed in 16 (40 %) patients, with 6 patients meeting criteria for major infection. Overall, PCT was found to be highly specific for all infections and the subcategory of major infections (97 and 93 %, respectively) with related high negative predictive values. Odds ratio for elevated PCT with clinical infections ranged from 25.2 (95 % CI 2.7-233) to 33.3 (95 % CI 4.3-261) for all and major infections, respectively. Related receiver operating characteristic curves for elevated PCT were 0.74 and 0.96 for all and major infections, respectively.

CONCLUSIONS

Procalcitonin of 0.2 ng/mL or greater was demonstrated to be very specific for sepsis among patients with aSAH. Further studies should validate this result and establish its clinical applicability.

Use of serum procalcitonin to detect bacterial infection in patients with autoimmune diseases: a systematic review and meta-analysis

OBJECTIVE

To systematically review evidence of the accuracy of the procalcitonin test for diagnosis of bacterial infection in patients with autoimmune disease.

METHODS

The major databases Medline, EMBase, and the Cochrane Library were searched for studies published between January 1966 and October 2011 that evaluated procalcitonin, alone or in comparison with other laboratory markers such as C-reactive protein (CRP), as a diagnostic marker for bacterial infection in patients with autoimmune disease and provided sufficient data to permit construction of 2 × 2 tables.

RESULTS

Nine studies were included in the final meta-analysis. The area under the summary receiver operating characteristic curve values were 0.91 (95% confidence interval [95% CI] 0.88-0.93) for procalcitonin and 0.81 (95% CI 0.78-0.84) for CRP. In general, testing for procalcitonin was highly specific for identifying infectious complications, although it was not as sensitive as testing for CRP. Pooled sensitivity was 0.75 (95% CI 0.63-0.84) for procalcitonin tests and 0.77 (95% CI 0.67-0.85) for CRP tests. Pooled specificity was 0.90 (95% CI 0.85-0.93) for procalcitonin tests and 0.56 (95% CI 0.25-0.83) for CRP tests. The positive likelihood ratio for procalcitonin (7.28 [95% CI 5.10-10.38]) was sufficiently high to qualify procalcitonin testing as a rule-in diagnostic tool, while the negative likelihood ratio (0.28 [95% CI 0.18-0.40]) was not sufficiently low to qualify procalcitonin testing as a reliable rule-out diagnostic tool.

CONCLUSION

Procalcitonin has higher diagnostic value than CRP for the detection of bacterial sepsis in patients with autoimmune disease, and the test for procalcitonin is more specific than sensitive. A procalcitonin test is not recommended to be used in isolation as a rule-out tool.