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Background: Collection of epidemiological data and care of patients are hampered by lack of access to laboratory diagnostic equipment and patients' health records in resource-limited settings. We engineered a low-cost mobile device that combines cell-phone and satellite communication technologies with fluid miniaturization techniques for performing all essential ELISA functions., Methods: We assessed the device's ability to perform HIV serodiagnostic testing in Rwanda and synchronize results in real time with electronic health records. We tested serum, plasma, and whole blood samples collected in Rwanda and on a commercially available sample panel made of mixed antibody titers., Results: HIV testing on 167 Rwandan patients evaluated for HIV, viral hepatitis, and sexually transmitted infections yielded diagnostic sensitivity and specificity of 100% and 99%, respectively. Testing on 40 Rwandan whole-blood samples-using 1 μL of sample per patient-resulted in diagnostic sensitivity and specificity of 100% and 100%. The mobile device also successfully transmitted all whole-blood test results from a Rwandan clinic to a medical records database stored on the cloud. For all samples in the commercial panel, the device produced results in agreement with a leading ELISA test, including detection of weakly positive samples that were missed by existing rapid tests. The device operated autonomously with minimal user input, produced each result 10 times faster than benchtop ELISA, and consumed as little power as a mobile phone., Conclusions: A low-cost mobile device can perform a blood-based HIV serodiagnostic test with laboratory-level accuracy and real-time synchronization of patient health record data., (© 2012 American Association for Clinical Chemistry)

More than half a million Americans became newly infected with human immunodeficiency virus (HIV) in the first decade of the new millennium. The domestic epidemic has had the heaviest impact on men who have sex with men and persons from racial and ethnic minority populations, particularly black persons. For example, black men who have sex with men represent <1% of the US population but 25% of new HIV infections, according to Centers for Disease Control and Prevention estimates published in 2008. Although black and Hispanic women constitute 24% of all US women, they accounted for 82% of HIV infections among women in 2005, according to data from 33 states with confidential name-based reporting. There is a nearly 23-fold higher rate of AIDS diagnoses among black women (45.5 diagnoses per 100,000 women) and a nearly 6-fold higher rate among Hispanic women (11.2 diagnoses per 100,000 women), compared with the rate among white women (2.0 diagnoses per 100,000 women). Investigators from the HIV Prevention Trials Network, a National Institutes of Health-sponsored collaborative clinical trials group, have crafted a domestic research agenda with community input. Two new domestic studies are in progress (2009), and a community-based clinical trial feasibility effort is in development (2010 start date). These studies focus on outreach, testing, and treatment of infected persons as a backbone for prevention of HIV infection. Reaching persons not receiving health messages and services with novel approaches to both prevention and treatment is an essential priority for control of HIV infection in the United States; our research is designed to guide the best approaches and assess the impact of bridging treatment and prevention.

Rates of invasive disease caused by penicillin-resistant pneumococci are rising. Previous reports have found no association between resistant pneumococci and increased mortality. To evaluate the impact of penicillin resistance and other variables on mortality, we retrospectively studied all cases of pneumococcal bacteremia identified by our microbiology laboratory from 1 January 1992 through 31 December 1996. There were 462 cases of pneumococcal bacteremia in 432 patients. The mean age was 35 years; 55% of the cases occurred in male patients, 58% were in black patients, and 40% were in Hispanic patients. One-half of the cases occurred in patients with documented human immunodeficiency virus (HIV) infection. Penicillin resistance was first noted in 1994 and increased yearly, accounting for 17% of 1996 isolates. Of all resistant isolates, 65% were resistant to penicillin at a high level. The overall mortality was 17%. On multivariate analysis, high-level penicillin resistance, older age, severe disease, multilobar infiltrates and/or effusion(s) on chest roentgenogram, and Hispanic ethnicity were independent predictors of mortality in pneumococcal bacteremia. In HIV-infected patients, a CD4 cell count below the median just missed statistical significance. This is the first report demonstrating penicillin resistance as an independent predictor of mortality among patients with pneumococcal bacteremia.

For hospitalized patients with smear-positive pulmonary or laryngeal tuberculosis, the Centers for Disease Control and Prevention recommends that three consecutive sputum samples be negative for acid-fast bacilli (AFB) before respiratory isolation is discontinued. Limited data are available to predict the length of time to obtain three negative sputum smears and cultures and to determine factors associated with a prolonged interval before sputum smear and culture conversion, especially among patients infected with human immunodeficiency virus (HIV). For 100 consecutive patients with smear-positive pulmonary tuberculosis, the mean and median numbers of days from the initiation of appropriate therapy to the first of three consecutive negative smears were calculated, and associated risk factors were determined. The mean number of days before the first of three consecutive negative sputum smears was 33 days; the median was 23 days. On stepwise multiple regression analysis, cavitary disease, numerous AFB on the initial smear, and no prior history of tuberculosis were the factors independently associated with an increased number of days for both smear and culture conversion. HIV does not prolong the period of infectiousness.