pH and amine test to diagnosis of vaginal infections

• US 5,910,447 A
• Filed: 03/18/1997
• Issued: 06/08/1999
• Est. Priority Date: 08/13/1996
• Status: Expired due to Fees

• Current Assignee: Litmus Concepts, Inc. (Quidel Corporation)
• Original Assignee: Litmus Concepts, Inc. (Quidel Corporation)
• Inventors: Lawrence, Paul J., Ly, Peter U., Shockey, David R.
• Primary Examiner(s): ALEXANDER, LYLE
• Application Number:
  US08/819,789
• Time in Patent Office: 812 Days
• Field of Search: 422/56, 422/58, 422/61, 436/111, 436/163
• US Class Current: 436/111
• CPC Class Codes: G01N 31/221 for investigating pH value
• CPC Class Codes: G01N 33/52 Use of compounds or compositions for colorimetric, spectrophotometric or fluorometric investigation, e.g. use of reagent paper and including single- and multilayer analytical elements immunological elements G01N33/54386; involving labelled immunochemicals G01N33/58; for haemoglobin or occult blood G01N33/72
• CPC Class Codes: G01N 33/84 involving inorganic compounds or pH
• CPC Class Codes: Y10T 436/173845 Amine and quaternary ammonium

Abstract

Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable means rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

Claims

1. A method for the identification of a condition indicative of bacterial vaginosis in a patient by analyzing a sample of vaginal fluid from said patient, said method comprising determining whether said vaginal fluid tests positive in both of the following tests:

(1) a test for pH equal to or greater than a selected transition point within the range of 4.6 to 4.8, performed by applying said sample to a composition comprising a first pH indicator containing an ionizable phenol group and a negatively charged group, dispersed in a solid hydrophilic fluid-permeable polymer containing quaternary ammonium groups in sufficient quantity to immobilize said pH indicator against diffusion when wetted with an aqueous liquid sample and to cause said indicator to change color at said first selected transition point; and

(2) a test for salts of volatile amines, performed by applying said sample to a solid alkali and a gas-permeable indicator lamina of material permeable to gas but impermeable to aqueous liquids, impregnated with an indicator that undergoes a detectable transition upon contact with amines.

2. A method for the identification of a condition indicative of bacterial vaginosis in a patient by analyzing a sample of vaginal fluid from said patient, said method comprising determining whether said vaginal fluid tests positive in at least three of the following four tests:

(1) a test for pH equal to or greater than a selected transition point within the range of 4.6 to 4.8, performed by applying said sample to a composition comprising a first pH indicator containing an ionizable phenol group and a negatively charged group, dispersed in a solid hydrophilic fluid-permeable polymer containing quaternary ammonium groups in sufficient quantity to immobilize said pH indicator against diffusion when wetted with an aqueous liquid sample and to cause said indicator to change color at said first selected transition point;

(2) a test for salts of volatile amines, performed by applying said sample to a solid alkali and a gas-permeable indicator lamina of material permeable to gas but impermeable to aqueous liquids, impregnated with an indicator that undergoes a detectable transition upon contact with amines;

(3) a test for homogeneity of vaginal fluid; and

(4) a test for the presence of clue cells.