# US 2013/0157301 A1 · Diagnosis of bacterial meningitis based on the measure of ROS production in a sample of cerebrospinal fluid > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0157301 A1 - Document ID: US20130157301A1 - Status: Published application - Kind: A1 - Application number: 13/811,860 - Filed: 2011-07-26 - Published: 2013-06-20 - Earliest claimed: 2010-07-26 - Assignees: Assistance Publique-Hopitaux de Paris - Inventors: Anne-Claire Lukaszewicz; Ingrid Ouanounou; Didier Payen De La Garanderie - Web page: https://patentgrep.com/patent/US20130157301A1 ## CPC - C12Q 1/04: Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} - G01N 33/5091: {for testing the pathological state of an organism} - G01N 33/84: involving inorganic compounds or pH - G01N 2800/52: Predicting or monitoring the response to treatment, e.g. for selection of therapy based on assay results in personalised medicine; Prognosis - C12Q: MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS (immunoassay G01N33/53); COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract The present invention pertains to a method for in vitro diagnosing a bacterial infection in a biological fluid selected amongst cerebrospinal fluid, ascitic fluid, pericardial fluid, pleural fluid, urine and synovial fluid, based on the measure, in a sample of said fluid, of the production of reactive oxygen species (ROS); a high level of ROS production is indicative of the presence of activated polymorphonuclear neutrophils (PMNs) in said fluid, which in turn is a hallmark of bacterial infection. ## Claims ### Claim 1 A method for in vitro diagnosing a leukocytosis and/or a bacterial infection in a biological fluid selected from the group consisting of cerebrospinal fluid, ascitic fluid, pericardial fluid, pleural fluid, urine and synovial fluid, comprising a step of measuring, in a sample of said fluid collected from a subject, the production of reactive oxygen species (ROS), wherein a ROS production above a predetermined threshold is indicative of a leukocytosis and/or a bacterial infection. ### Claim 2 (depends on 1) The method of claim 1, comprising a step of measuring the level of ROS spontaneously produced by polymorphonuclear neutrophils (PMNs) present in the sample of biological fluid, wherein a ROS production above a predetermined threshold is indicative of a bacterial infection in said biological fluid. ### Claim 3 (depends on 1) The method of claim 1, comprising a step of measuring the level of ROS produced by the PMNs present in the sample of biological fluid after stimulation by an agonist of NADPH oxidase, wherein a ROS production above a predetermined threshold is indicative of a leukocytosis in said biological fluid. ### Claim 4 (depends on 1) The method of claim 1, wherein the measure of ROS production by the PMNs present in the sample of biological fluid is performed at most eight hours after sample collection. ### Claim 5 (depends on 1) The method of claim 1, wherein ROS production is measured in a sample of cerebrospinal fluid, and wherein a spontaneous ROS production above a predetermined threshold is indicative of bacterial meningitis. ### Claim 6 (depends on 5) The method of claim 5, wherein the cerebrospinal fluid sample is from a patient in a situation selected from the group consisting of brain trauma, invasive intracranial procedures and suspected community meningitis. ### Claim 7 (depends on 1) The method of claim 1, comprising the steps of (i) measuring the level of ROS spontaneously produced by the PMNs present in the sample of biological fluid, and (ii) measuring the level of ROS produced by the PMNs present in the sample of biological fluid after stimulation by an agonist of NADPH oxidase, wherein: a) if the level measured in step (i) is below a first predetermined threshold and the level measured in step (ii) is below a second predetermined threshold, it can be concluded that there is no bacterial infection in the biological fluid; b) if the level measured in step (i) is above a first predetermined threshold, a bacteriological analysis of the sample is performed; and c) if the level measured in step (ii) is above a second predetermined threshold, a bacteriological analysis of the sample is performed. ### Claim 8 (depends on 7) The method of claim 7, wherein if the level measured in step (i) is above a first predetermined threshold, decision is made to treat the patient with antibiotics without waiting the result of bacterial analysis. ### Claim 9 (depends on 1) The method according to claim 1, wherein ROS production is measured by putting a sample of biological fluid in presence of a colorimetric reagent sensitive to ROS. ### Claim 10 (depends on 1) The method according to claim 1, for in vitro following the efficiency of an antibiotic treatment in a patient having a bacterial infection in a biological fluid selected from in the group consisting of cerebrospinal fluid, ascitic fluid, pleural fluid, urine and synovial fluid, comprising a step of measuring, in a sample of said fluid, the production of radical oxygen species (ROS), wherein a decrease in ROS production after the beginning of the antibiotic treatment indicates that said treatments is appropriate. ### Claim 11 (depends on 1) The method according to claim 1, for in vitro detecting a treatment failure, comprising a step of measuring the production of radical oxygen species (ROS) in a cerebrospinal fluid sample collected after the beginning of said treatment, wherein a ROS production above a predetermined threshold in said sample is indicative of treatment failure. ### Claim 12 (depends on 1) The method according to claim 1, wherein reactive nitrogen species (RNS) production is measured in place or in addition to reactive oxygen species (ROS) production. ### Claim 13 (depends on 1) A diagnostic kit for performing a method according to claim 1, comprising a reagent which can react with reactive oxygen species and/or reactive nitrogen species, and a notice of use indicating how to interpret the results. ### Claim 14 (depends on 13) The diagnostic kit according to claim 13, comprising a colorimetric reagent, the colour of which changes in presence of ROS and/or RNS. ### Claim 15 (depends on 14) The diagnostic kit according to claim 14, comprising a testing strip and a notice of use indicating the correspondence between the colour of the strip after incubation with a sample of biological fluid and the likelihood of bacterial infection in said fluid.