METHOD AND DEVICE FOR ASSESSING A STATUS OF A WOUND OF A PATIENT

Abstract

The present invention relates to a method for assessing a status of a wound of a patient, comprising the steps of i. determining a concentration of one or more inflammatory markers in a sample from the wound, wherein the sample comprises or consists of wound fluid and the one or more inflammatory markers may indicate an inflammation within the wound, ii. determining a concentration of one or more bacterial markers in the sample, wherein the one or more bacterial markers may indicate a colonization of the wound with metabolically active bacteria, iii. assessing the status of the wound based on the concentrations of the one or more inflammatory markers and the one or more bacterial markers, wherein the status of the wound is assessed as being inflamed or not inflamed and as being colonized with metabolically active bacteria or not colonized with metabolically active bacteria. This diagnostic method allows a reliable, specific and detailed assessment of the status of the wound.

Claims

1. Method for assessing a status of a wound of a patient, comprising the steps of determining a concentration of one or more inflammatory markers in a sample from the wound, wherein the sample comprises wound fluid and the one or more inflammatory markers may indicate an inflammation within the wound, determining a concentration of one or more bacterial markers in the sample, wherein the one or more bacterial markers may indicate a colonization of the wound with metabolically active bacteria, and assessing the status of the wound based on the concentrations of the one or more inflammatory markers and the one or more bacterial markers, wherein the status of the wound is assessed as being inflamed or not inflamed and as being colonized with metabolically active bacteria or not colonized with metabolically active bacteria.

2. Method of claim 1, wherein the one or more inflammatory markers are selected from the group consisting of activated protein C, arginase, calprotectin, cathepsin G, interleukin-1 alpha, interleukin-1 beta, lysozyme, matrix metalloproteinase 2, matrix metalloproteinase 9, matrix metalloproteinase 13, myeloperoxidase, neutrophil elastase, soluble intercellular adhesion molecule-1, tumor necrosis factor alpha, uric acid, xanthine oxidase, and mixtures thereof.

3. Method of claim 1, wherein the one or more bacterial markers are selected from the group consisting of a coagulase, an enzyme, a metabolite, a siderophore, a signaling molecule, a virulence factor, and mixtures thereof.

4. Method of claim 3, wherein the coagulase is selected from the group consisting of staphylocoagulase, von Willebrand factor binding protein, clumping factor A, clumping factor B, and mixtures thereof.

5. Method of claim 3, wherein the enzyme is alkaline phosphatase or nitrate reductase.

6. Method of claim 3, wherein the metabolite is selected from the group consisting of acetoin, acetone, ammonia, nitrate, nitrite, and mixtures thereof.

7. Method of claim 3, wherein the siderophore is selected from the group consisting of acinetobactin, aerobactin, baumannoferrin, enterobactin, fimsbactin, staphyloferrin A, staphyloferrin B, pyochelin, pyoverdine, salmochelin, yersiniabactin, and mixtures thereof.

8. Method of claim 3, wherein the signaling molecule is a quorum sensing molecule, in particular indole or autoinducer-2.

9. Method of claim 3, wherein the virulence factor is a quorum sensing regulated molecule, in particular selected from the group consisting of alkaline protease, alpha-toxin, y-hemolysin, LasA protease, LasB elastase, LecA lectin, LukDE, LukGH (LukAB), panton-valentine-leukocidin (PVL), a phenol soluble modulin (PSM), pyocyanin, a rhamnolipid, and mixtures thereof.

10. Method of claim 1, wherein the status of the wound is assessed by comparing the determined concentrations of the one or more inflammatory markers and the one or more bacterial markers with predetermined concentrations for the one or more inflammatory markers and the one or more bacterial markers, the status of the wound may in particular be assessed as being inflamed if the one or more inflammatory markers are contained in the sample above predetermined concentrations, and/or the status of the wound may in particular be assessed as being not inflamed if the one or more inflammatory markers are contained in the sample in or below predetermined concentrations, and/or the status of the wound may in particular be assessed as being colonized with metabolically active bacteria if the one or more bacterial markers are contained in the sample above predetermined concentrations, and/or the status of the wound may in particular be assessed as being not colonized with metabolically active bacteria if the one or more bacterial markers are contained in the sample in or below predetermined concentrations.

11. Method of claim 1, wherein the method further comprises a step of determining a pH value of the sample which may indicate a poorly healing or non-healing wound.

12. Method of claim 1, wherein the method further comprises a step of assessing if an anti-inflammatory treatment and/or an antibacterial treatment of the wound is indicated or not based on the status of the wound.

13. Method of claim 1, wherein the concentrations of the markers are determined by a method selected from the group consisting of an enzymatic, immunological, colorimetric, fluorimetric, radioactive, spectrophotometric analytical methods, and mixtures thereof.

14. Method of claim 1, wherein the concentrations of the markers are determined by a dipstick type test.

15. Device for assessing a status of a wound of a patient, comprising means for determining a concentration of one or more inflammatory markers in a sample from the wound, wherein the sample comprises or consists of wound fluid and the one or more inflammatory markers may indicate an inflammation within the wound, means for determining a concentration of one or more bacterial markers in the sample, wherein the one or more bacterial markers may indicate a colonization of the wound with metabolically active bacteria, and means for indicating the concentrations of the one or more inflammatory markers and the one or more bacterial markers, wherein the device may in particular be adapted to perform a method of claim 1.

16. Wound dressing comprising a device of claim 15.

17. Method of using one or more inflammatory markers in combination with one or more bacterial markers for assessing a status of a wound of a patient, wherein the one or more inflammatory markers may indicate an inflammation within the wound and wherein the one or more bacterial markers may indicate a colonization of the wound with metabolically active bacteria, comprising performing the method of claim 1.

Description

FIRST EXAMPLE OF USE (TEST STRIP)

[0057] Home-care nurses face many times patients with pressure ulcers that might be only inflamed, and not needing extra care, or, worst, being infected and needing antibiotics or further hospital assistance care to avoid further complications. By evaluating the status of the wound with a diagnostic device according to a preferred embodiment of the present invention, the nurse will either take a sample of wound fluid with a syringe or disposable pipette and apply small quantities of the wound fluid to a test strip. In the case of wounds with enough exudate, the nurse can also apply the wound fluid to the test strip by contacting the test strip with the wound surface for a sufficient time. The test strip is adapted to generate a color pattern indicating the presence or absence of at least one inflammatory marker and at least one bacterial marker in the wound fluid. For example, the test strip may be reactive to neutrophil elastase and/or TNF-α as inflammatory marker(s) and ammonia and/or alkaline phosphatase as bacterial marker(s). Based on the number of inflammatory and/or bacterial markers present in the wound fluid, the nurse will be able to quickly make an appropriate treatment decision, avoiding for example the use of antibiotics when it is not needed.

SECOND EXAMPLE OF USE (LABORATORY TEST)

[0058] A health care professional in a hospital (inpatient or outpatient department) needs to decide whether a wound with clinical signs of infection requires antibiotic treatment or not. A swab is taken and send to the central laboratory. There the swab is rehydrated with an appropriate solution and tested for the presence of inflammatory mediators (for example IL-1 beta, calprotectin (S100A8/A9) and/or myeloperoxidase) and bacterial metabolites (for example acetoin, acetone, ammonia and/or nitrite). Different to current practice of culturing bacteria from swabs the presence of bacterial metabolites indicates bacterial metabolism and is independent of the cultivation time of the bacteria (allowing a quick test result) and bacterial viability on the swab, which might decay during transport to the laboratory.

THIRD EXAMPLE (DETECTION OF ALKALINE PHOSPHATASE)

[0059] A chromogenic substrate (e.g. 4-nitrophenylphosphate-2CHA) with a phosphorylated end is immobilized on the surface of the test strip. By applying the wound fluid (either by the direct absorption of the fluid on the wound or by applying the wound fluid extracted from the wound) to the labeled area of the test strip, the bacterial alkaline phosphatase enzyme (when present in the wound fluid) will cleave the phosphate end of the substrate and release a chromogenic product which leads to the formation of a color change visible with the naked eye.

FOURTH EXAMPLE (DETECTION OF COAGULASES)

[0060] Latex particles coated with fibrinogen are immobilized to the test strip to detect clumping factor of Staphylococcus aureus. By wetting the test strip with wound fluid, a rapid agglutination occurs and can be observed with the naked eye.

FIFTH EXAMPLE (DETECTION OF COAGULASES)

[0061] After soaking the test strip with wound fluid, the nurse in charge adds a drop of a reagent containing latex particles coated with fibrinogen to the test strip labeled area and a rapid agglutination occurs through the interaction of fibrinogen and clumping factor. This agglutination is visible with the naked eye.

SIXTH EXAMPLE (DETECTION OF NITRATE REDUCTASE)

[0062] The nitrate reduction test determines the production of the enzyme nitrate reductase, which results in the reduction of nitrate (NO.sub.3.sup.−) to nitrite (NO.sub.2.sup.−). Nitrate is immobilized to the test strip on a specific area labeled for the detection of nitrate reductase. After soaking or adding the wound fluid to the test strip, the nurse in charge adds a drop of a reagent containing sulfanilic acid and alfa-naphthylamine to produce prontosil, a red precipitate, which formation is visible with the naked eye.