System and method for determining onset and disease progression
The invention disclosed herein concerns screening and early detection of a variety of disease conditions in seemingly healthy subjects, enabling early intervention and treatment.
1. A method for identifying in a breath sample from a subject an early onset of a bacterial disease state and treating the bacterial disease state by detecting the presence of at least one disease-associated cluster of volatile compounds indicative of the bacterial disease, the method comprising;
at a first time, exposing a first breath sample of the subject to at least one first sampling unit comprising one or more adsorbing regions capable of reversibly associating volatile compounds in said breath sample, the adsorbing region being different from a metallic surface or metallic nanoparticle, desorbing adsorbed compounds, analyzing an identity of the adsorbed compounds after desorbing the adsorbed compounds, and determining a level of the at least one disease-associated cluster of volatile compounds;
at an at least one consequent further time point, exposing a breath sample of the subject to a further sampling unit comprising one or more adsorbing regions capable of reversibly associating to volatile compounds in said breath sample, desorbing a adsorbed compounds, analyzing an identity of the adsorbed compounds after desorbing the adsorbed compounds, and determining a level of the at least one disease-associated cluster of volatile compounds;
comparing the level of the cluster of volatile compounds associated with said disease of said at least one first sampling unit and the level of said further sampling unit;
wherein an increase or a decrease of at least 50% in the level associated with the further sampling unit compared to that of the first sample unit is indicative of the early onset of said disease state; and
responsive to comparing the level of the cluster of volatile compounds, beginning a therapeutic treatment or modifying the therapeutic treatment.
2. The method according to claim 1 , wherein each of the one or more adsorbing regions is configured to reversibly associate to the volatile compounds in said breath sample.
3. The method according to claim 1 , wherein the one or more adsorbing regions being formed of a solid adsorbent configured to physically trap the volatile compounds, selected from the group consisting of at least one material selected from organic porous polymers, ion-exchange resins, carbon molecular sieves, and sulfonated polymers, a material selected amongst carbon adsorbents, carbon allotropes or carbonaceous materials, wherein the one or more adsorbing regions is a material having a surface area between 5 and 1500 m 2 /g, a density of between 0.2 and 0.7 and/or a micropore diameter between 4 and 300 A.
4. The method according to claim 1 , wherein following exposure of the one or more adsorbing regions to a breath sample, said adsorbing regions are treated to cause desorption or dissociation of the volatile compounds from the surface, and analyze the desorbed volatiles.
5. The method according to claim 4 , wherein the volatile compounds are analyzed by gas-chromatography (GC), GC-lined mass-spectrometry (GC-MS), proton transfer reaction mass-spectrometry (PTR-MS), electronic nose device (E-nose), quartz crystal microbalance (QCM), infra-red spectroscopy (IR) or ultraviolet spectroscopy (UV).
6. The method according to claim 1 , wherein the bacterial disease is caused by a bacterium selected from Bacillus anthracis; Clostridium botulinum; Francisella tularensis; Yersinia pestis; Burkholderia pseudomallei; Burkholderia mallei; Clostridium perfringens; Coxiella burnetii; Brucella melitensis, abortus , suis and canis; Staphylococcus aureus; Rickettsia prowazekii; Chlamydia psittaci ; Food and Waterborne Pathogens such as Escherichia coli, Vibrio cholerae, Salmonella species, Shigella species, Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica; Mycobacterium tuberculosis ; and other Rickettsia.
7. The method according to claim 1 , wherein the disease is a hospital associated infection (HAI), caused by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), Clostridium difficile, Acinetobacter baumannii , or multi-drug resistant (MDR) Acinetobacter sp.
8. A method for determining an onset of ventilator-associated pneumonia (VAP) in a ventilated subject and treating the ventilated subject, the method comprising;
at a first time point, exposing a first breath sample from the ventilated subject to at least one first sampling unit comprising one or more adsorbing regions capable of reversibly associating to volatile compounds in said first breath sample, desorbing adsorbed compounds, analyzing an identity of the adsorbed compounds after desorbing the adsorbed compounds, and determining a level of at least one disease-associated cluster of volatile compounds;
at an at least one consequent further time point, exposing a breath sample from the ventilated subject to a further sampling unit comprising one or more adsorbing regions capable of reversibly associating to volatile compounds in said breath sample, desorbing adsorbed compounds, analyzing an identity of the adsorbed compounds after desorbing the adsorbed compounds, and determining the level of the at least one disease-associated cluster of volatile compounds;
comparing the level of the cluster of volatile compounds of a VAP-causing pathogen of said at least one first sampling unit and the level of said further sampling unit, wherein the VAP-causing pathogen is a bacterium;
wherein increase or a decrease of at least 50% in the level associated with the further sampling unit compared to that of the first sample unit is indicative of an early of onset of VAP; and
responsive to comparing the level of the cluster of volatile compounds, beginning a therapeutic treatment or modifying the therapeutic treatment.
9. The method according to claim 8 , wherein the at least one sampling unit is provided in a respiratory system used in ventilating the subject.
10. The method according to claim 8 , wherein the at least one sampling unit is in a form of a vessel comprising the one or more adsorbing regions and allowing a timed residence contact of the breath sample with the one or more adsorbing regions.
11. The method according to claim 8 , the method comprising detaching the at least one sampling unit from the outlet line of the respiratory system, desorbing the absorbed volatile compounds, and analyzing the volatile compounds to determine the level of volatile compounds adsorbed onto the one or more adsorbing regions.
12. The method according to claim 8 , wherein analysis is carried out by a spectrometric method.
13. The method according to claim 1 , wherein the bacterial disease is VAP.
14. The method according to claim 1 wherein the patient is a ventilated subject.
15. The method according to claim 8 , wherein the at least one disease-associated cluster of volatile compounds includes compounds selected from those discharged to the surroundings by the disease-associated VAP pathogen, wherein the relative amounts of each of the volatile compounds produced and discharged to the surroundings of the pathogen are captured, identified and quantified forming a database of cluster of compounds indicative of the VAP pathogen.
16. The method according to claim 1 , wherein the disease-associated cluster of volatile compounds comprises compounds selected from: 1,8-naphthyridine, 10-undecyn-1-ol, 3-methyl-1-butanol, 1-phenyl-1H-imidazole, 2-(2-pyridinyl)-1H-indole, 8-methyl-1H-purine, 1-methoxyphthalazine, 1-nitro-2-propanol, 2-butyl-1-octanol, 3,7-dimethyl-1-octanol, 2-methyl-1-propanol, 1-undecene, 2-(2-methylpropyl)-3,5-di (1-methylethyl)pyridine, 2,3-dimethylcyclohexylamine, 2,4-dithiapentane, 2-benzyl-1-methylpiperidine, 2-butanone, 3-propylidene-2-heptanone, 6-phenylhexanoic acid, 8-aminocaprylic acid, 2,2′-thiobis-acetic acid, acetone, O-isopropyloxime benzaldehyde, 4-nitro-benzamide, 2-carboxy-benzeneacetic acid, 2-methyl-butanal, 3-methyl-butanal, 3-methyl-butanoic acid, dodecamethyl-cyclohexasiloxane, cyclohexene, D: C-Friedours-7-ene, dimethyl trisulfide, dimethyl disulfide, emorfazone (4-ethoxy-2-methyl-5-morpholin-4-ylpyridazin-3-one), ethylphenylhydantoin, gabapentin lactam, ethyl 5-oxohexanoate, 5-nitro-isoquinoline, lanostan-12-one, luminol (5-amino-2,3-dihydrophthalazine-1,4-dione), 4-butyl-phenol, phthalic anhydride, pregabalin, 1-(ethynylsulfinyl)-propane, ribo-ribo disaccharide, S-(2-benzothiazolyl) cysteine, and 2-butyl-5-ethyl-thiophene.
17. The method according to claim 1 wherein the further time point being from hours after said first time point to 1, 2, 3, 4, or 5 days after said first time point.
18. The method according to claim 8 wherein said further time point being from hours after said first time point to 1, 2, 3, 4, or 5 days after said first time point.
19. The method according to claim 18 wherein VAP is indicative after 48 hours.
20. The method according to claim 8 , wherein the volatile compounds are selected from dimethyl disulfide, dimethyl trisulfide, 2-butanone, 2-methyl-butanal, 2,3-butanedione, butanoic acid-2-methyl-ethyl ester, 2-ethyl-1-hexanol, 3-methyl-butanal, and 2-methyl-1-propanol.
21. The method of claim 8 , wherein the cluster of volatile compounds are selected from the group of dimethyl disulfide, dimethyl trisulfide, 2-butanone and 2-methyl-butanal; or from the group of dimethyl sulfide, 2,3-butanedione, butanoic acid-2-methyl-ethyl ester, and 2-ethyl-1-hexanol, 3-methyl-butanal.
22. The method according to claim 1 , wherein the at least one disease-associated cluster of volatile compounds includes compounds selected from those discharged to the surroundings by the disease-associated pathogen, wherein the relative amounts of each of the volatile compounds produced and discharged to the surroundings of the pathogen are captured, identified and quantified forming a database of cluster of compounds indicative of the pathogen.