Home Diagnostics

Heterogeneous immunoassays may be used with conventional microtiter systems in clinical laboratories, but have also been adapted for doctor s office and home diagnostic test devices. For example, a device for detecting antibodies to the human immunodeficiency virus (HIV), operates as shown in Figure 6.10.19... 

The simple handling makes the sensor well suited for use in the doctor s office and for patient home diagnostics. 

Monoclonal Antibody-Based, In-Home Diagnostic Kits... 

With the increased availability of a variety of home diagnostic tests, the sale of home pregnancy, ovulation, and fertility tests alone was a 330 million dollar business in 2005. Home pregnancy tests have been utilized since 1976, with approximately 26 devices currently available in the United States. These tests claim that they can be utilized on the first day of a missed menstrual period (or, for oertain devioes, even earlier) with more than 99% diagnostic accuracy for pregnancy. Despite these claims, accurate results are obtained only a fraction of the time (Table 46.1) (1). 

Comstock, J., 2012, "Scanadu unveils smartphone-enabled home diagnostics." mobileHealth-News. Accessed March 24, 2014. http //mobihealthnews.com/19288/scanadu-unveils-smart phone-enabled-home-diagnostics/. 

The main development in medical diagnostic reagents since the 1960s has been the steady growth of dry (soHd-phase) chemistry systems. Dry chemistry systems have made substantial gains over wet clinical analysis in the number of tests performed in hospitals, laboratories, and homes because of ease, rehabiUty, and accuracy. 

Because the sheer magnitude of the tests performed in laboratory diagnosis is so great, e.g., over 3,600 tests in the alphabetical index of the laboratory tests offered by UCLA Medical Center [4], a single example will be illuminated to demonstrate a particular use of biologically derived diagnostics in home pregnancy test. 

Dyed particles also are commonly used in diagnostic lateral flow tests (like the common home pregnancy test), as the colors can be seen with the eye without the need for special detectors. In this type of assay, antibodies or antigens are coupled to the dyed particles and a sample solution applied to the test strip carries them along within a membrane. The particles then are captured at points in the membrane that represent either a control or a positive sample result. Large numbers of color particles docking at these points within the membrane create the visual lines associated with these disposable tests. 

Clinical utility takes the concept a step further and shows that the patient s medical outcome is favorably influenced by knowledge of the diagnostic test. An example would be that the tight insulin control that is only possible with frequent home blood glucose monitoring has a positive impact on delay of complications of diabetes. FDA does not require that a demonstration of clinical utility be performed in support of submissions but does... 

In this chapter, we will focus primarily on treatments for the substance use disorders. However, because detoxification during a substance-induced withdrawal is often the first step in treating a substance use disorder, we will discuss withdrawal states to some extent. The substance use disorders include both substance abuse and the more serious substance dependence. Substance abuse consists of a pattern of misuse that causes recurring problems in at least one aspect of life. This can be a failure to fulfill responsibilities at home or work, reckless use of the substance such as drunken driving, repeated substance-related arrests, and ongoing substance use despite resulting problems in family relationships. See Table 6.1 for the diagnostic criteria for substance abuse. 

Bastian, L.A., K. Nanda, V. Hasselblad, and D. L. Simel. Diagnostic Efficiency of Home Pregnancy Test Kits A Meta-analysis. Archives of Eamily Medicine 7 no. 5 (1998) 465-469. 

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