The present invention relates generally to skin testing for allergic or other diagnostic reasons. More particularly, the present invention relates to methods and devices related to rapid testing of multiple allergens or multiple levels of allergens that can be administered in the office of a primary care physician or of a specialist.
When confronted with patients having possible allergies, a primary care physician (PCP) has a number of choices. The PCP can refer the patient to a specialist for a relatively involved skin test, often called a scratch test, where, after scratching, abrading, scarifying, or otherwise piercing the epidermal skin layer, suspect allergens are applied to the exposed skin tissue. This form of test can involve multiple visits and involves significant time and cost for the patient. These known tests involve individually filling wells with allergens, which are then applied to the patient by applicators dipped into these wells. Such tests are time consuming, and allow the increased possibility of errors. In addition, this exhaustive, lengthy form of testing isn't always necessary. Alternatively, the PCP can administer blood (RAST) tests, knowing that the results will be delayed for 1-2 weeks and the accuracy is inferior to that of the skin test standard. Often, PCPs recommend their patients to make changes to their environments and/or prescribe medications based solely on patient's medical history. This leads to often confusing results as to the actual cause and some environmental changes (e.g.; removal of a family pet) can be too traumatic to be practical. Therefore, there is a need for a reliable and rapid testing mechanism for on-site allergy testing that a PCP's staff as well as a specialist can administer.
Because there are numerous potential sources for allergic reactions, prior art skin testing apparatuses have been designed in an effort to improve testing time through the use of multi-headed applicators. These applicators, however, tend to be bulky and hard to use, as well as expensive. Moreover, the head of each applicator needs to be loaded with an allergen individually, which is time-consuming and prone to mistakes. Results of such skin testing are often hard to read and cross-contamination of allergens is a general concern that is often not adequately addressed. Therefore, there is a need for simple, economic and reliable testing mechanisms in which multiple allergens can be tested simultaneously on the skin of patients with results that are easily observable.
These and other needs are met by rapid allergy testing systems, as provided herein.
According to one aspect, a disposable allergy-testing patch is provided. The patch is defined by a flexible body having a plurality of packets, each said packet housing an allergen, and at least one transferable marking material adjacent each packet that is disposed on one surface of the flexible body. The marking material marks a patient's body upon close contact as an indicator of the allergen applied, a location registration and potentially other information relevant to executing and evaluating the test. In one feature, each packet further houses at least one piercing element that is movably supported within the packet. Retaining means are included for retaining a portion of the allergen when at least a portion of the piercing element is forced through the packet.
In one version, the patch further includes actuation means for moving the piercing element at least partly out of the packet to enable a portion of the piercing element, including the portion that retains allergen from the packet, to extend outwardly from the body. In one embodiment, the actuation means comprises at least one tubular section made from a low durometer elastomeric material that is sized for retaining at least a portion of said piercing element. Each tubular section is configured to deform upon compressive contact of the patch surface with the skin of a patient, permitting the piercing element to move in relation to the tubular portion in order to advance the piercing element in relation to the packet through the tubular portion and into direct contact with the skin.
According to another aspect, an allergy-testing apparatus is provided comprising a disposable patch comprising a flexible body having at least one packet housing an allergen, at least one transferable marking material adjacent said at least one packet and disposed on one surface of said flexible body for marking a patient's skin upon close contact therewith, and at least one piercing element movably contained within said patch and configured to pierce a portion of said at least one packet, said at least one piercing element including retaining means for retaining a portion of said allergen, said at least one piercing element being configured to pierce said packet, wherein said apparatus is configured to advance said retaining means towards said body surface and said at least one transferable marking material into close contact with the skin of a patient indicating the allergen applied and other test-related information.
In yet another aspect, an allergy-testing apparatus is provided having an actuating device comprising a compact body, an actuator mechanism and an engagement surface, said actuator mechanism being operatively connected to at least a portion of said engagement surface such that operation of said actuator mechanism causes spatial displacement of said at least a portion of said engagement surface relative to said compact body, a packet assembly comprising at least one packet housing an allergen, said packet assembly being releasably attached to said engagement surface of said actuating device, and at least one piercing element having a fluid retaining end, wherein spatial displacement of said engagement surface caused by said operation of said actuator mechanism deploys said piercing element such that said fluid retaining end pierces at least one side of said packet, enabling administration of said allergen to a patient.
According to yet another aspect, an allergy-testing apparatus is provided comprising a scope comprising a compact hand-held body, an illumination assembly disposed in connection with said body, an optical system disposed within said body, an engagement surface, and a substrate comprising at least one packet housing an allergen and a piercing element, said substrate being releasably attached to said engagement surface of said scope.
According to still another aspect, a disposable allergen-testing applicator is provided that includes at least one piercing element having an elongated body extending from a base end to a tip end, said tip end comprising at least one sharp tip, said body comprising a shoulder at a predetermined distance relative to said sharp tip, said tip end containing an allergen suspended thereon by at least one capillary action and surface adhesion, at least one enclosure into which said at least one piercing element is disposed, said enclosure having an opening that permits the passage of said tip end, said enclosure being made from a deformable material enabling the tip end of said piercing member to extend beyond said opening upon application of an external force onto said applicator, and a sealing strip covering said enclosures and said piercing elements.
According to one version of the applicator, each enclosure is defined by a substantially Y-shaped wall member disposed around the body of said piercing element, including said tip end, said wall member closely enclosing a portion of said piercing element, from said base end of said piercing element to a deflective point not beyond said shoulder of said piercing element, said wall member extending away from said body of said piercing member between said deflective point and said tip end of said piercing element, said wall member terminating in a rim, and a removable cover sealing said rim of said wall member and forming an interstice around said piercing element's tip end.
According to yet another aspect, an allergen-testing apparatus is provided that includes a body comprising a curved engagement surface, a handle coupled to said body such that operation of said handle causes movement of said curved engagement surface, and a disposable applicator removably attached to and in conforming relationship with said curved engagement surface, said applicator comprising a plurality of piercing elements, each element having an allergen disposed on a tip end thereof, and a corresponding plurality of enclosures retaining said piercing elements, including associated tip ends, each of said enclosures being deformable based on a force applied by a user through said handle to permit the tip end of at least one enclosure to extend, thereby permitting administration of said allergen to the skin of a patient. In one preferred version, the curved engagement surface assumes a convex configuration.
An advantage of the present invention is that the herein described allergy testing apparatuses provide simplified care and provide more timely and cost effective answers during the visit to one's PCP; i.e., quick results to common allergies are available without another appointment or referral to a specialist for lengthy, costly exhaustive testing. Disposable patches containing an array of common allergens or allergen levels can be easily administered by a physician, nurse or medical assistant with minimal discomfort to the patient, simplifying the more extensive and uncomfortable scratch test. Since the injection sites are labeled with temporary marks to facilitate identification of allergic reactions, there is little chance of confusion. Using this invention, the PCP is better able to accurately reach a diagnosis or determine the appropriate next steps (in terms of diagnosis and/or treatment) for those suspected of allergies. In addition to more effectively dealing with specific allergies, a further advantage of this invention is that it reduces the expense and risk of overtreatment of patients who do not actually have allergies, or do not have a suspected allergy.
Still other aspects, embodiments and advantages are discussed in detail below with regard to the following Detailed Description, which should be read in conjunction with the accompanying drawings.
The invention is herein described, by way of example only, with reference to the accompanying drawings. It is stressed that the particulars shown in the drawings are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented to provide exemplary versions to provide a proper understanding of the advantageous features of the allergy test apparatus. Other versions should be readily apparent to those of ordinary skill embodying the concepts described herein. In addition, certain terms are used throughout in order to provide a suitable frame of reference with regard to the accompanying drawings. These terms, however, are not intended to be limiting, except where specifically noted.
Referring to
The packets 26 may protrude from the patch's top surface 25 or the bottom surface 27 or both surfaces. The packets 26 may be made from the same material as the substrate 24 or from a different though preferably flexible and fluid-impermeable material. Sealed within each of the packets 26 is either an allergen or a control reagent. In one embodiment, each packet 26 also contains at least one piercing element (not shown). Obviously, the number and distribution pattern of the packets 26 may vary as well as the size and shape of the patch 20. In the embodiment shown, the disposable allergy-testing patch 20 is substantially round, about 1-2 inches in diameter, and has about ten small packets distributed about its perimeter. In one embodiment, each of the packets 26 contains one of the ten most common allergens that cause, in combination, a majority, e.g., about 90%, of the environmental allergies, including, for example, pollens, dust mites, mold spores, latex, insect venom, medicines, etc. In another embodiment, each of the packets 26 contains one of the ten most common allergens that cause, in combination, a majority, e.g., about 90%, of the food allergies, including, for example, milk, eggs, peanuts, tree nuts, fish, shellfish, soy, wheat, etc. In yet another embodiment, the packets 26 represent a subcategory of the environmental or food allergies, e.g., grass, and will represent, say, ten different types of common grasses. Optionally, one or two of the packets 26 can contain a positive control and/or a negative control, respectively.
Specifically referring to
An advantage of having at least one marking material 28 on the testing patch 20 that transfers directly unto the skin is that it allows simultaneous testing of multiple patches on the same patient without having to worry about mixing up test results, and hence saving time for both the healthcare staff and the patient. This is particularly advantageous in the case of testing children on whom, due to the limited size of testable area, more patches could be needed for testing the same number of allergens than on adults.
An advantage of marking all of the test sites is that it allows the practitioner to rapidly and accurately identify the allergen responsible for an allergic reaction. It also prevents possible errors made using the current technique where allergens are poured into wells that the injectors are then dipped into before application. The marking further serves as a reference as to the location of the overall patch as applied.
Specifically referring to
Referring now to
A central pin 48 matches the central bore 29 of the disposable patch 20, so that a user can align the two to load the patch onto the engagement surface 44. A protrusion 54 is provided on the engagement surface 44 that matches the position notch 23 on the patch 20 such that each packet 26 aligns with a piercing element 47. After the patch 20 has been loaded onto the engagement surface 44, the cover 30 is removed from the patch to reveal each packet 26 along with the adjacent transferable marking material 28 on the patch bottom surface 27 (
Once the patch 20 has made full contact against the patient body, the user activates the actuator 40 by simply pressing on the button 50. Each hidden piercing element 47 pierces through both surfaces of each packet 26 into the skin, resulting in rapid injection of test reagents. Rapid injection of multiple allergen tests is advantageous because it minimizes discomfort for the patient. Piercing elements useful for skin scratch tests are well known in the art, and typically have fluid retaining ends that, through capillary action, retain sufficient amounts of allergen extracts to result in visible allergic reactions. Some examples of piercing elements 47 are shown in
After the user administers the skin scratch test using the actuator 40 and patch 20 of the present apparatus, the actuator loaded with the patch 20 is removed from the patient body. The patch 20 is peeled off from the actuator 40 and discarded. Transferable marking material 28 has automatically labeled each injection site, so that when the user inspects afterwards, there is no confusion as to which allergen has caused a reaction. Typically, the user waits for about 15 minutes before looking for positive reactions such as wheals above a certain size (e.g., about 4 mm in diameter) on the patient's skin.
Accordingly, the rapid allergen testing systems described herein are easy to use and provide substantial information in a short period of time, with accuracy comparable to that of existing scratch tests and higher than that of blood/RAST tests. Armed with this information about potential allergies, a PCP can make a more informed decision on succeeding steps (e.g., other testing for source of symptoms, treatments, referral to a specialist, etc.).
Referring now to
The all-in-one patch 70 described herein can be manually applied, i.e., a user can administer the scratch test by applying pressure directly by his or her hand on the outside of the support 71 to pierce each packet 26 and to “scratch” the skin. However, to rapidly inject multiple test allergens with uniform pressure, according to one feature of the invention, an actuator 80 is provided for applying and actuating the all-in-one patch 70. Referring to
When administering the test, the all-in-one patch 70 is first loaded onto the actuator 80 by matching the patch's central bore 29 onto the central pin 48, and with the top surface, the side that has the relatively hard support 71 for the piercing elements, facing the engagement surface 44. Then the user contacts the bottom surface 27 of the patch 70, as much as possible, with a skin testing area of the patient. Subsequently, the user presses the button 50 on the actuator 80 to push the engagement surface 44 towards the patient. As shown in
Referring now to
The engagement surface 100 is provided to serve a similar function as the engagement surfaces described above in association with other actuator embodiments of the present invention, and can be used in those embodiments as well. Benefits described with regard to other actuator embodiments, such as uniform depth control, apply here as well. In this specific example, the engagement surface 100 is formed in a ring configuration, which is sized and shaped to fit over the scope distal end 94 and is also connected to one side of the scope body 92 through a hinge 102. As a result, a user can lift a tab 104 opposite the hinge 102 and ply the engagement surface 100 from the scope distal end 94, enabling the surface to be flipped or lifted hingeably to an opposing side (
Referring now to
Optional elements of this embodiment include a measuring reticle integral to the optical system. Using this reticle, the user may more quickly determine if the criteria for a positive reaction has been met (e.g., wheal of over 4 mm diameter, etc.).
Because the scope 90 is able to illuminate and magnify the view at the test site, diagnostic accuracy is improved. Further, smaller piercing elements and less amount of allergen may be extract needed, reducing the footprint of each individual allergy test. Accordingly, more allergy tests can be fitted into the same amount of skin area or the same number of allergy tests requires less skin area. This not only increases the efficiency of allergy testing, but also reduces discomfort for the patient, and is especially advantageous in pediatric care.
Referring now to
Each individual applicator 114 houses one of an allergen extract or a control reagent and at least one piercing element (not shown). Each individual applicator 114 includes a vial 124 and a base 126. In the illustrated example, the vial 124 has a substantially uniform diameter—as will be described below, that is not the only configuration useful for the present invention. A removable sealing strip 128 caps the distal tips of all the applicators 114 and retains the allergen extract inside the applicators 114 until use. In one version, the entire applicator assembly 110 can be manufactured from disposable materials and discarded after a single use or single-patient use.
Referring now to
The vial 124 provides enclosure for a reservoir around the piercing tip 130 that stores a liquid allergen extract 34 or a control reagent (positive or negative). The vial's distal rim 134 defines a distal opening that is covered by the removable seal 128. In one feature, the vial wall is made from a deformable material that collapses, folds or flexes to allow the piercing tip 130 to extend beyond the distal opening when an external force tries to move the applicator 114 in the distal direction against a barrier, such as the skin. In a preferred embodiment, the vial wall consists of a substantially Y-shaped wall member 136 around the piercing element's elongated body 125, i.e., the wall member 136 closely encloses the portion of the elongated piercing body 125 from the base 126 to a flex point 138 that is below the shoulder 132 of the piercing element 47. The vial wall member 136 extends away from the piercing element's elongated body 125 between the flex point 138 and the piercing tip 130, terminating at the distal rim 134. As noted above, the sealing strip 128 seals the rim 134. However, this strip 128 also forms an interstice around the piercing tip 130 that is normally filled with a liquid allergy extract or control reagent. In one embodiment, the vial wall member 136 is molded from a relatively low durometer elastomer, e.g., silicone rubber and the like.
Referring specifically to
Referring now to
Referring now to
Again, the application of multiple allergens through one common applicator assembly 110, especially when the application process is accomplished through an actuator 140 that has a singular engagement surface 146, uniformity in depth control is much more likely to be achieved. This form of application provides at least one major advantage over prior art applicators that require an operator to dip a piercing means into each well of allergen before individually applying the piercing means to the skin.
While the present invention has been particularly shown and described with reference to the structures and methods disclosed herein and as illustrated in the drawings, it is not confined to the details set forth and this invention is intended to cover any modifications and changes as may come within the scope and spirit of the following claims.