title: Dried tube specimens: a simple and cost-effective method for preparation of HIV proficiency testing panels and quality control materials for use in resource-limited settings.
abstract: HIV testing has rapidly expanded worldwide, but proficiency testing (PT) programs to monitor and improve the quality of testing are often lacking in resource-limited settings (RLS). Traditional PT programs and quality control reagents use serum or plasma specimens requiring stringent conditions for storage and transportation. A novel, simple and easy to use approach, based on dried tube specimens (DTS), was developed that can help monitor the quality of HIV antibody testing in RLS. DTS were prepared by drying 20 microl of specimen overnight at room temperature. The addition of a green dye (0.1%) made the DTS pellets visible without affecting the test results. Before testing, the DTS were rehydrated with 200 microl of PBS-Tween buffer. A panel of 303 DTS samples (135 HIV positive and 168 HIV negative) was evaluated with two rapid tests. Sensitivity and specificity with the Determine HIV-1/2 test were 99.3% and 99.4%, respectively, and with OraQuick were 98.5% and 100%, respectively. Stability studies showed that HIV-specific antibodies in the DTS specimens were stable at 4 degrees C and 25 degrees C for 4 weeks, with only marginal decline at 37 degrees C and 45 degrees C over 4 weeks. The DTS-based PT program was piloted successfully in 24 testing sites in Kenya. Results demonstrate that the DTS is a simple to use, practical method to prepare and distribute PT panels and quality control specimens to monitor HIV testing practices in RLS.
authors.affiliation: International Laboratory Branch, Division of Global AIDS, Centers for Disease Control and Prevention, Atlanta, GA 30345, USA. bparekh@cdc.gov
authors.forename: Bharat S
authors.initials: BS
authors.lastname: Parekh
authors.forename: Juliana
authors.initials: J
authors.lastname: Anyanwu
authors.forename: Hetal
authors.initials: H
authors.lastname: Patel
authors.forename: Marie
authors.initials: M
authors.lastname: Downer
authors.forename: Mireille
authors.initials: M
authors.lastname: Kalou
authors.forename: Catherine
authors.initials: C
authors.lastname: Gichimu
authors.forename: Bera Steven
authors.initials: BS
authors.lastname: Keipkerich
authors.forename: Nelly
authors.initials: N
authors.lastname: Clement
authors.forename: Michael
authors.initials: M
authors.lastname: Omondi
authors.forename: Oren
authors.initials: O
authors.lastname: Mayer
authors.forename: Chin-Yih
authors.initials: CY
authors.lastname: Ou
authors.forename: John N
authors.initials: JN
authors.lastname: Nkengasong
mesh_terms: D003906:Developing Countries; D015483:HIV Antibodies / Q000097:blood*; D015658:HIV Infections / Q000175:diagnosis* / Q000821:virology; D015497:HIV-1 / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007630:Kenya; D011786:Quality Control; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000191:economics / Q000379:methods* / Q000592:standards*; D013696:Temperature; D013997:Time Factors; D014773:Virology / Q000191:economics / Q000379:methods* / Q000592:standards*
chemical_list: D015483:HIV Antibodies