DIAGNOSIS AND TREATMENT METHODS FOR ENTRY OF GASTROINTESTINAL CONTENTS INTO RESPIRATORY TRACT

Abstract

A method of diagnosing in a subject for the purpose of determining if the subject's gastrointestinal contents has entered the subject's respiratory tract. The qualitative analysis can be also expanded into quantitative analysis, enabling the estimation of either the concentration, or the amount, or both, of the gastrointestinal contents that entered the respiratory tract. The invention also provides methods of treatment based on the identification of aspiration using the methods of the invention.

Claims

1. A method of determining the amount of gastric contents in the respiratory fluid of a subject, comprising: a) orally administering to a subject a diagnostic formulation comprising cromolyn or a cromolyn salt; b) allowing the diagnostic formulation to remain in the subject over a period of time during which the subject would be expected to aspirate the diagnostic formulation from the gastrointestinal tract into the respiratory tract; c) obtaining a sample of a body fluid selected from urine, blood or a blood product; and d) analyzing the body fluid to determine the amount of cromolyn or cromolyn salt in the body fluid, wherein the amount of cromolyn or cromolyn salt in the body fluid is indicative of the amount of aspiration of gastrointestinal contents into the respiratory tract.

2. The method of claim 1, wherein the body fluid in step c) is urine.

3. The method of claim 1, wherein the body fluid in step c) is blood or a blood product.

4. The method of claim 1, further comprising: e) administering a control formulation comprising cromolyn or cromolyn salt to the subject; f) allowing the control formulation to remain in the subject over a period of time during which the subject would not be expected to aspirate the control formulation from the gastrointestinal tract into the respiratory tract; g) obtaining a sample of a body fluid body fluid selected from urine, blood or a blood product from the subject following the administration of the control formulation; h) analyzing the body fluid of step g) to determine the level of the diagnostic agent; i) comparing the level of diagnostic agent from step d) to the level of diagnostic agent of step h); and j) determining if the level of diagnostic agent detected following administration of the diagnostic formulation is indicative of a disease associated with aspiration of gastrointestinal contents into the respiratory tract using the compared levels of diagnostic agent in step i).

5. The method of claim 4, wherein the control formulation is administered orally.

6. The method of claim 4, wherein the control formulation is administered by inhalation.

7. A method of determining the amount of gastric contents in the respiratory fluid of a subject, comprising: (a) orally administering to the mammal a diagnostic formulation comprising a diagnostic agent that is not absorbed from the gastrointestinal tract of the mammal but is absorbed from the respiratory tract of the mammal; (b) allowing the diagnostic formulation to remain in the mammal over a period of time during which the mammal would be expected to aspirate the formulation from the gastrointestinal tract into the respiratory tract; (c) obtaining a sample of a body fluid selected from urine, blood or a blood product; and (d) analyzing the body fluid to detect the level of the diagnostic agent in the body fluid; and (e) determining if the fluid contains a level of the diagnostic agent indicative of aspiration of gastrointestinal contents into the respiratory tract.

8. The method of claim 7, wherein the administered diagnostic agent is selected from the group consisting of cromolyn salts, cromolynic acid, nedocromil, nedocromil salts and muscarinic acid receptor antagonists.

9. The method of claim 7, wherein the administered agent is a cromolyn salt.

10. The method of claim 7, further comprising: (g) administering a control formulation comprising the same diagnostic agent as found in the diagnostic formulation to the subject at an occasion different to that when the orally administered diagnostic formulation is administered; (h) obtaining the body fluid of claim 1 from the subject following the administration of the control formulation, wherein the body fluid is blood, serum, plasma or urine; (i) analyzing the body fluid to determine if the body fluid contains the diagnostic agent; and (j) determining if the level of diagnostic agent detected following administration of the diagnostic formulation is indicative of aspiration of gastrointestinal contents into the respiratory tract by comparison of the level of the diagnostic agent detected in the body fluid following administration of the diagnostic formulation to the level of diagnostic agent detected in the body fluid following administration of the control formulation.

11. The method of claim 7, wherein the control formulation is administered orally.

12. The method of claim 7, wherein the control formulation is administered by inhalation.

13. The method of claim 7, wherein the body fluid is obtained following the administration of the control formulation and prior to analyzing the body fluid.

14. The method of claim 7, wherein the control formulation is administered during a period of time when the subject is not expected to experience aspiration of gastrointestinal contents into the respiratory tract.

15. The method of claim 7, further comprising: (g) administering a control formulation comprising the same diagnostic agent as found in the diagnostic formulation to the subject at an occasion different to that when the diagnostic formulation is administered; (h) obtaining a body fluid from the subject following the administration of the control formulation, wherein the body fluid is urine, blood or a blood product; (i) analyzing the body fluid to determine if the body fluid contains the diagnostic agent; and (j) determining if the level of diagnostic agent detected following administration of the diagnostic formulation is indicative of aspiration of gastrointestinal contents into the respiratory tract by comparison of the level of the diagnostic agent detected in the body fluid following administration of the diagnostic formulation to the level of diagnostic agent detected in the body fluid following administration of the control formulation.

16. The method of claim 15, wherein the control formulation is administered orally.

17. The method of claim 15, wherein the control formulation is administered by inhalation.

18. The method of claim 15, wherein the body fluid is obtained following the administration of the control formulation and prior to analyzing the body fluid.

19. The method of claim 15, wherein the control formulation is administered during a period of time when the subject is not expected to experience aspiration of gastrointestinal contents into the respiratory tract.

20. The method of claim 15, further comprising detecting a level of the diagnostic agent indicative of aspiration of gastrointestinal contents into the respiratory tract based on the level of the diagnostic agent observed following administration of the control formulation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0075] Before the present methods and formulations are described, it is to be understood that this invention is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

[0076] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.

[0077] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some potential and preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. It is understood that the present disclosure supersedes any disclosure of an incorporated publication to the extent there is a contradiction.

[0078] It must be noted that as used herein and in the appended claims, the singular forms a, an, and the include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a particle includes a plurality of such particles and reference to the label includes reference to one or more labels and equivalents thereof known to those skilled in the art, and so forth.

[0079] The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.

[0080] The invention includes different methods for diagnosing respiratory fluid in a subject wherein the respiratory fluid has been regurgitated from the gastrointestinal tract from the subject. The method includes orally administering to a subject a formulation comprised of a plurality of particles which particles are comprised of a biocompatible material such as a biocompatible polymer or a wax such as a caruba wax wherein the particles include some type of detectable lable which may be a fluorescent label, a radioactive label, a magnetic label or a UV detectable label. The formulation is allowed to remain in the subject over a period of time during which the subject would be expected to aspirate the formulation from the gastrointestinal tract. For example, the subject might be administered the formulation just prior to going to sleep. After allowing for sufficient time respiratory fluid is extracted from the patient. That respiratory fluid is analyzed in order to determine if it contains the detectable label.

[0081] Once the patient has been determined as aspirating fluid from the gastrointestinal tract into the respiratory tract the patient will require treatment. That treatment involves orally administering to the subject a formulation which comprises a pharmacological substance. That pharmacological substance or pharmaceutically active drug is administered in order to reduce or prevent aspiration of fluid from the gastrointestinal tract into the respiratory tract. The pharmaceutically active drug is preferably a drug which acts locally on the gastrointestinal tract and is not absorbed systemically. Examples of such drugs are drugs selected from the group consisting of cromolyn salts, cromolynic acid, nedocromil, nedocromil salts or muscarinic acid receptor antagonist.

[0082] Dosing of the drug to the patient will vary depending on a wide range of factors including the patient's age, size, weight, sex and condition. However, dosing of the drug to the patient is generally carried out by oral administration of the drug in the form of pills, capsules or solutions. Pills and capsules may contain the drug in combination with a pharmaceutically acceptable excipient. Solutions or suspensions may contain the drug in an aqueous solution or suspension with pharmaceutically acceptable carriers.

[0083] The oral formulation may be administered to the subject just prior to going to bed at night. Further, additional doses may be administered during the night depending on the subjects responsiveness to the medication. The dose may be administered before and/or after an activity such as going to sleep which is likely to result in aspirations. That activity can be going to sleep for the evening, taking an afternoon nap, or after eating a large meal or drinking heavily.

[0084] In one embodiment of the invention patients undergoing lung transplants are treated prophylactically in order to reduce or prevent intestinal fluid into the newly transplanted lung.

[0085] The dosing amount will also vary with the particular drug. When administering cromolyn and in particular cromolyn salts currently marketed safe dosages for children for other indications have been shown to be in the range of about 20 mg 4 times per day to 40 mg 4 times per day. Adults have been dosed in the amount of 200 mg 4 times per day to 400 mg 4 times per day.

[0086] The formulation may include both an immediate release component where a drug is immediately released and a controlled release component where the drug is not released immediately (e.g. over the first hour) but released gradually during hours 2 to about 8 hours after administration. Oral liquid formulations can be viscous formulations which provide a degree of coating to the gastrointestinal tract.

[0087] When administering cromolyn in order to carry out diagnostics the cromolyn should be delivered with significant amount of water, e,g. 6 oz or more, 12 oz or more, 16 oz or more of water. However, when the cromolyn is being administered in order to treat the subject it is preferably delivered in the absence of water or with a very small amount of water e.g. 4 oz or less, 2 oz or less, 1 oz or less.

EXAMPLES

[0088] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention nor are they intended to represent that the experiments below are all or the only experiments performed. Efforts have been made to ensure accuracy with respect to numbers used (e.g. amounts, temperature, etc.) but some experimental errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, molecular weight is weight average molecular weight, temperature is in degrees Centigrade, and pressure is at or near atmospheric.

Example 1

Fluorescein-Spray Drying

[0089] Prepare nuclei of <1 micron fluorescein particles by spray drying aqueous solutions of fluorescein. Then condense vapors of respiratory-tract compatible waxes such as carnauba was upon the fluorescein particles completely encapsulating the fluorescein. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, add flavor etc. Subject swallows a precise amount of the liquid suspension prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0090] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The sample may be diluted in additional water, or a solvent that dissolves the wax. The fluorescent label is then released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0091] The concentration of material in the respiratory tract entering due to reflux is estimated from the intensity of fluorescence using one of many detectors for fluorescence. The important parameter is the concentration of the fluorescent label per volume of the airway fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents in the respiratory tract.

Example 2

Fluorescein-Flow Focusing

[0092] Prepare nuclei of <1 micron fluorescein particles by extruding a biocompatible wax (carnauba) in an outer tube and a fluorescein label in an inner tube in order to completely encapsulate the fluorescein. Details of the flow focusing method are described in U.S. Pat. No. 6,116,516 and related issued patents, all of which are incorporated herein by reference. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, add flavor etc. Subject swallows a precise amount of the liquid suspension prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0093] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The sample may be diluted in additional water, or a solvent that dissolves the wax. The fluorescent label is then released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0094] The concentration of material in the respiratory tract entering due to reflux is estimated from the intensity of fluorescence using one of many detectors for fluorescence. The important parameter is the concentration of the fluorescent label per volume of the airway fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents in the respiratory tract.

Example 3

Magnetic Particles-Flow Focusing

[0095] Magnetic particles may be suspended in a formulation and then swallowed for the diagnostic purposes described in this invention. However, it may be desirable to protect these particles from digestion in the gastrointestinal tract. Further, unencapsulated magnetic particles could be harmful to either the gastrointestinal tract, or the respiratory tract, or both. Using the flow focusing method it is possible to manufacture biocompatible encapsulated magnetic particles that are not digested in the gastrointestinal tract. Prepare nuclei of <1 micron magnetic particles by extruding a biocompatible wax (carnauba) in an outer tube and a magnetic particle label in an inner tube in order to completely encapsulate the magnetic particle. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, add flavor etc. Subject swallows a precise amount of the liquid suspension prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0096] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The concentration of the gastrointestinal contents in the respiratory tract can be estimated by collecting with a magnet the magnetic particles and then counting them using one of the many methods available for such counting, or by measurement of the total magnetism. The sample may be also diluted in additional water, or a solvent that dissolves the wax. The magnetic particles can then be released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0097] The important parameter is the concentration of the magnetic particle label per volume of the airway fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents aspirated into the respiratory tract.

Example 4

UV Labeled Particles-Flow Focusing

[0098] Prepare nuclei of <1 micron UV labeled particles by extruding a biocompatible wax (carnauba) in an outer tube and a UV label or UV labeled particle in an inner tube in order to completely encapsulate the UV labeled particle. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, add flavor etc. Subject swallows a precise amount of the liquid suspension prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0099] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The sample may be diluted in additional water, or a solvent that dissolves the wax. The UV labeled particle is then released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0100] The amount of material in the respiratory tract entering due to reflux is estimated from the UV labeled particles detected using standard detectors. The important parameter is the concentration of the UV labeled particles per volume of the respiratory fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents aspirated into the respiratory tract.

Example 5

Phosphorescent Particles-Flow Focusing

[0101] Prepare nuclei of <1 micron phosphorescent labeled particles by extruding a biocompatible wax (carnauba) in an outer tube and a phosphorescent labeled particle in an inner tube in order to completely encapsulate the phosphorescent labeled particle. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, add flavor etc. Subject swallows a precise amount of the liquid suspension prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0102] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The sample may be diluted in additional water, or a solvent that dissolves the wax. The phosphorescent labeled particle is then released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0103] The amount of material in the respiratory tract entering due to reflux is estimated from the phosphorescent labeled particles detected using standard detectors. The important parameter is the concentration of the phosphorescent labeled particles per volume of the airway fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents aspirated into the respiratory tract.

Example 6

Fluorescein-Flow Focusing with Cromolyn Sodium

[0104] Prepare nuclei of <1 micron fluorescein particles by extruding a biocompatible wax (carnauba) in an outer tube and a fluorescein label in an inner tube in order to completely encapsulate the fluorescein. Make a suspension of these particles in water using usual pharmaceutical methods to stabilize these, dissolve cromolyn sodium and add flavor etc. Subject swallows a precise amount of the liquid suspension including the dissolved cromolyn sodium prior to activity that is causing GIT reflux (e.g., prior to going to sleep).

[0105] The health care provider takes a sample of airway fluid through induced coughing, bronchoscopy, spontaneous coughing etc. The sample may be diluted in additional water, or a solvent that dissolves the wax. Fluorescein is then released either as a result of the addition of a suitable solvent, or by increasing the temperature to dissolve the wax, or both.

[0106] If the carnauba wax particles were suspended in a solution of cromolyn, blood or urine samples are also taken and checked for cromolyn to estimate the total amount of gastrointestinal contents that entered the respiratory tract . The amount of cromolyn in the blood or urine shows how much of the formulation of cromolyn swallowed did enter the respiratory tract, because cromolyn will not enter the blood stream, or urine,via the GI tract.

[0107] The fluorescein particles encapsulated in carnauba wax enter the respiratory tract if the subject aspires the contents of her/his gastrointestinal tract. Fluorescein can be released from the carnauba wax particles present in the respiratory fluid by heating or dissolving the wax using organic solvents. The concentration of material in the respiratory tract entering due to such aspiration is estimated using one of many methods to detect and quantify fluorescein. The important parameter is the concentration of fluorescein per volume of the airway fluid in which it was contained as that is likely to be related to the harmful effects of the gastrointestinal contents aspirated into the respiratory tract. The presence of cromolyn in a body fluid such as plasma, serum or preferably urine can be quantified by a variety of methods used to measure cromolyn concentrations, such as HPLC with a suitable detector or radioimmunoassay. Measurement of samples of body fluid enables to estimate the total amount of cromolyn that entered the respiratory tract, and therefore provides an estimate of the total amount of gastrointestinal fluid that entered the patient's respiratory tract. Therefore, the combination of the two diagnostic agents provides estimates of both the concentration of the gastrointestinal fluid in the respiratory tract as well as the total amount of the contents of gastrointestinal fluid that entered the respiratory tract.

Example 7

Treatment of Aspirations of Gastrointestinal Contents Into the Respiratory Tract

[0108] The subject swallows prior to going to bed an aqueous suspension of carnauba wax particles that contain encapsulated fluorescein. The subject then collects any sputum that has been spontaneously produced overnight. If insufficient sputum is obtained, the subject is administered a mist of hypertonic saline by inhalation to induce sputum production. The sputum sample is diluted with a high pH buffer and organic solvent immiscible with water is added to extract the wax. The aqueous phase is separated and a sample is analyzed for fluorescence using a fluorescence detector such as a fluorimeter. If the fluorescence intensity exceeds the limit previously established for healthy subjects, it is assumed that the subject who has just undergone the test suffers from aspirations of gastrointestinal contents into the respiratory tract. The test may need to be repeated several times in case the aspirations do not occur every night, especially if the subject already has a condition that is suspected to cause such aspirations, or the subject has respiratory symptoms of aspirations. When the diagnosis is confirmed, the subject takes (prior to going to bed) a dose of cromolyn sodium and collects urine samples overnight as well as the first thing in the morning. The subject then either sends the urine sample for analysis of cromolyn to a laboratory, or uses a dipstick test at home. The subject repeats the test for several days. If the amount of cromolyn detected in the urine does not exceed the amounts typically found in subjects without aspirations, or the cromolyn concentration in the urine continues to get smaller upon successive testing, it may be concluded that cromolyn (in this subject) is effective to minimize or prevent aspirations of gastric contents into the respiratory tract and it will be therefore used for this purpose for as long as the condition exists, or the treatment ceases to be effective.

Example 8

Treatment of Aspirations of Gastrointestinal Contents Into the Respiratory Tract

[0109] The subject swallows prior to going to bed an aqueous suspension of carnauba wax particles that contain encapsulated fluorescein. The subject then collects any sputum that has been spontaneously produced overnight. If insufficient sputum is obtained, the subject is administered a mist of hypertonic saline by inhalation to induce sputum production. The sputum sample is diluted with a high pH buffer and organic solvent immiscible with water is added to extract the wax. The aqueous phase is separated and a sample is analyzed for fluorescence using a fluorescence detector such as a fluorimeter. If the fluorescence intensity exceeds the limit previously established for healthy subjects, it is assumed that the subject who has just undergone the test suffers from aspirations of gastrointestinal contents into the respiratory tract. When the diagnosis is confirmed, the subject takes (prior to going to bed) carnauba wax particles that contain encapsulated fluorescein, suspended in an aqueous solution of cromolyn sodium. The subject then collects a sputum sample in the morning, or goes to a healthcare professional who will collect a sample of the respiratory fluid which is then analyzed for the presence of the fluorescein. If the test is negative, the subject may need to repeat for several days to confirm that the cromolyn prevents or reduces the aspiration of gastrointestinal fluid into the respiratory tract.

[0110] The preceding merely illustrates the principles of the invention. It will be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. Furthermore, all examples and conditional language recited herein are principally intended to aid the reader in understanding the principles of the invention and the concepts contributed by the inventors to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. The scope of the present invention, therefore, is not intended to be limited to the exemplary embodiments shown and described herein. Rather, the scope and spirit of present invention is embodied by the appended claims.