HIV Enzyme-linked Immunosorbent Assay Research Articles

Clinical manifestations and outcomes of ocular syphilis in Asian Indian population: Analysis of cases presenting to a tertiary referral center.

Purpose:To describe disease manifestations and outcomes of ocular syphilis in Asian Indian population.Methods:Retrospective analysis of patients diagnosed with ocular syphilis at a tertiary referral center in India. Demographics, history, extraocular and ocular manifestations, ocular and systemic investigations, treatment and visual acuity outcomes were noted. All patients were diagnosed after necessary laboratory investigations including HIV ELISA (Human immunodeficiency virus, enzyme-linked immunosorbent assay), VDRL (venereal disease research laboratory), and TPHA (treponema pallidum hemagglutination).Results:Totally, 20 patients with mean age at presentation 38.25 ± 9.76 were analyzed. 9/20 patients had bilateral involvement. 8/20 had concurrent HIV at presentation with an average CD4 counts of 592.25 ± 411.34 cells/microliter. The mean duration of symptoms at time of presentation was 15.45 ± 35.15 weeks. VDRL test was reactive in 45% (9/20) patients whereas, all patients had a reactive TPHA test. Clinical manifestations included outer retinal placoid chorioretinitis lesions (8/20, 40%), followed by retinitis mimicking acute retinal necrosis as the second most common phenotype (4/20, 20%). Other presenting manifestations noted were panuveitis, miliary retinitis lesions, retinal vasculitis, intermediate uveitis, and anterior uveitis. The clinical phenotypes in immunocompromised included panuveitis, acute retinal necrosis and isolated anterior uveitis. Mean follow up duration was 6.32 ± 6.15 months. An improvement in mean best corrected visual acuity (BCVA) of (0.63 LogMAR, approximately 6 Snellen lines, P < 0.02) was noted at last follow-up.Conclusion:Phenotypic manifestations of ocular syphilis are varied. Non-treponemal tests like VDRL may be unreliable when compared with treponemal tests in diagnosing ocular syphilis. Syphilitic uveitis is considered equivalent to neurosyphilis and is treated similar to neurosyphilis.

Co-infection of malaria and HIV infection in severely undernourished children in the Democratic Republic of the Congo: a cross-sectional study.

This study aims to determine the prevalence of malaria and HIV seropositivity among children with undernutrition in the Democratic Republic of the Congo. A cross-sectional study of undernourished children aged between 12 and 60 months in Kalembe-Lembe hospital was carried out. Blood samples were collected for the analyses of malaria parasite, haemoglobin and haematocrit levels. HIV serostatus was determined with rapid HIV antibody tests and enzyme-linked immunosorbent assay. Logistic regression analyses were used to identify clinical predictors of HIV seropositivity. Of 225 children, 88.9% had malaria; the parasite loads were 16 000 para per μL (38.0%); 24 400 para per μL (56.8%), P < 0.001 and malaria and associated HIV infection accounted for 29.2%. In children aged >12 months, HIV seroprevalence was 29.3%; 86.0% had undernutrition and malaria, 6.8% had undernutrition and HIV and 4.3% had undernutrition, HIV and malaria (P < 0.001). The occurrence of at least three or more symptoms was highly specific (96.4-100.0%) for HIV seropositivity (P < 0.05). The overall mortality rate was 18.4%, higher in children with malaria and HIV (39.6% vs 12.2%, P < 0.001) and those with lower weight gain (4.3 vs 7.5 g kg-1 day-1, P < 0.001). There was high prevalence of malaria and HIV and mortality among severely undernourished children with malaria and HIV.

HIV Indeterminate Western Blot Results in Blood Donors in Northeast of Iran, 2009-2014

Background and Aims: HIV is spreading rapidly among people word wide. Infection with this virus leads to immune suppression and finally acquired immune deficiency syndrome (AIDS).Early HIV detection is depended on antibody screening against virus by Enzyme Linked Immunosorbent Assay (ELISA).Some confirmatory tests such as; Western Blot and Recombinant Immunobloting Assay (RIBA), are used to verify viral infection. Many of confirmatory tests results are indeterminate. The aim of this study is comparing the frequency and patterns of indeterminate results in two groups; blood donors and patients with high risk behaviors, in northeast of Iran. Materials and Methods: From October 2009 to March 2014 total number of 1055 serum samples with previous positive HIV ELISA test history, were tested in our laboratory. Some by RIBA and some by western blot method. Results: Most of indeterminate results belonged to blood donors that were tested by Western Blot analysis and were positive. The most reacting band was P24 in both methods and groups. Conclusion: RIBA assay is more sensitive and reliable than western Blot; but it’s necessary to use other supplementary tests with less indistinctive results.

Differences in Viral Load Testing Methodology May Play an Important Role in Optimizing the Initial Management of HIV-Infected Pregnant Women

One of the major success stories of HIV management is the significant drop in perinatal transmission rates. Much effort has been made in achieving a rate of 1100 cells/mm, by her report. Unfortunately, previous medical records were not available to verify her history. Testing was repeated at our center, with the HIV enzyme-linked immunosorbent assay (ELISA) as well as all Western blot bands returning positive, VL <75 copies/mL, and CD4 count 690 cells/mm. Viral load was performed using Versant HIV kPCR (Siemens Diagnostics, Malvern, PA, USA). We found it surprising that her VL was undetectable without therapy. After discussion with the National Clinician’s Consultation Center Perinatal HIV Hotline (1-888-448-8765), additional VL testing was sent to a laboratory that used real-time HIV-1 PCR (Abbott Molecular Diagnostics, Des Plaines, IL, USA) which has better sensitivity for groups N and O. The result from this assay returned with a VL of 108 copies/mL. Testing for HIV-1 DNA PCR was positive and HIV-2 DNA/RNA PCR was negative. An empiric regimen of abacavir (ABC)/lamivudine (3TC) and lopinavir/ ritonavir (LPV/r) was started in order to avoid hemosuppression that can be seen with zidovudine (ZDV). Repeat VL was undetectable thereafter using real time PCR. She delivered a healthy full-term infant whose HIV DNA PCRs remained negative. Numerous HIV-infected individuals with diverse viral genetic backgrounds are living in the United States. Choosing the correct testing method to determine antiretroviral therapy is essential in providing optimal care. Are current standards for HIV testing adequate to best manage these individuals? For the majority of infected pregnant patients, the answer is likely yes. Presently, 7 commercially available assays (only 4 with US Food and Drug Administration [FDA] approval) provide results with high sensitivity, specificity, and reproducibility. All are equipped to detect group M along with most of its 9 subtypes. Only the real-time PCR and Versant HIV kPCR can detect group O. Group N, however, can only be detected using the real-time PCR assay. Groups N and O are more commonly found in West-Central Africa, particularly Cameroon. Our patient came from a region that has higher rates of group O and may have been infected by someone from that region. In this situation, real-time PCR would be the correct method to determine the VL. Even though we believe the correct assay was used, our patient’s VL remained low, indicating that she was either an elite controller or the original PCR testing was inadequate. We suspect the former. As expected, commercial genotype testing failed due to a low VL. A blood sample sent to a research laboratory for further genotyping (using RT-PCR) determined that our patient had a pansensitive group M, subtype C virus (94.9% similarity to protease gene and 94.3% similarity to the reverse transcriptase gene) using the Stanford University HIV Drug Resistance Database. Health care providers should be mindful that there are subtle differences in VL testing methods. It is imperative that the type of assay chosen be based on the geographic location from where the infection was likely acquired. Although this does not

Seroprevalence of human immunodeficiency virus in north Indian blood donors using third and fourth generation Enzyme linked immunosorbent assay

Background:The percentage of HIV cases attributable to blood transfusion has decreased significantly in the last decade. The newer 4th generation Enzyme linked immunosorbent assay (ELISA) has been shown to have increased sensitivity compared to 3rd generation ELISA.Objectives:To estimate the seroprevalence of HIV among blood donors using 4th generation ELISA assay and to compare it with the 3rd generation ELISA.Materials and Methods:This prospective study involved 10,200 blood donors- 6,800 were voluntary donors (3400-students and 3400-non students) and 3400 were replacement donors. All blood units were tested with 3rd as well as 4th generation ELISA. All samples found reactive or in grey zone with either 3rd or 4th generation ELISA were retested by Western blot (WB).Results:The seroprevalence of HIV was estimated to be 1.37/1000 donations (0.14%) with 3rd generation ELISA compared to 3.62/1000 donations (0.36%) with 4th generation ELISA (p>0.05). The seroprevalence of HIV among voluntary donors was estimated to be 1.32/1000 donations (0.13%) with 3rd generation ELISA and 3.67/1000 donations (0.36%) with 4th generation ELISA. The prevalence of HIV among replacement donors was 1.47/1000 donations (0.15%) with 3rd generation ELISA and 3.52/1000 donations (0.35%) with 4th generation ELISA.Conclusion:4th generation HIV ELISA detects a higher number of seroreactive donors compared to 3rd generation ELISA. However, larger studies are required with confirmatory tests for both 3rd and 4th generation ELISA for making any policy changes.

Syphilis sero-positivity in recently admitted and long-term psychiatric inpatients: Screening, prevalence and diagnostic profile

Background. Syphilis research has neglected the prevalence of the disease among psychiatric patients, and traditional syphilis screening has been reported as inadequate. Objectives. (i) To assess the syphilis prevalence among psychiatric patients; (ii) to compare psychiatric diagnoses of syphilis-infected and -uninfected patients; (iii) to assess self-reported high-risk sexual behaviour; (iv) to establish syphilis/HIV co-morbidity; and (v) to investigate the performance of the rapid plasma reagin (RPR) test in syphilis screening, compared with the Treponema pallidum haemagglutination (TPHA) test. Methods. Psychiatric inpatients at Weskoppies Hospital, Pretoria, who consented to participate in the study (N=195) were categorised according to gender and length of admission (long-term or recent). Non-treponemal RPR, confirmatory TPHA, HIV-rapid and HIV enzyme-linked immunosorbent assay (ELISA) tests were performed. A reactive TPHA test was used to diagnose syphilis. Results. The estimated prevalence of syphilis was 11.7%. There was no significant association between TPHA sero-positivity and primary psychiatric diagnosis or self-reported high-risk sexual behaviour. Significant co-morbidity existed between syphilis and HIV (p=0.012). Compared with the TPHA test, the RPR test performed poorly, identifying only 2/23 patients who had a sero-positive TPHA test (8.7% sensitivity and 100% specificity). Conclusions. The prevalence of syphilis was higher than anticipated, supporting the need for routine testing. The significant co-morbidity and alarming prevalence of HIV and syphilis warrant testing for both conditions in all psychiatric admissions. Current syphilis screening with a single RPR test is inadequate; both RPR and TPHA tests should be performed.

Syphilis sero-positivity in recently admitted and long-term psychiatric inpatients: Screening, prevalence and diagnostic profile

&lt;p&gt;&lt;strong&gt;Background.&lt;/strong&gt; Syphilis research has neglected the prevalence of the disease among psychiatric patients, and traditional syphilis screening has been reported as inadequate.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Objectives.&lt;/strong&gt; (i) To assess the syphilis prevalence among psychiatric patients; (ii) to compare psychiatric diagnoses of syphilis-infected and -uninfected patients; (iii) to assess self-reported high-risk sexual behaviour; (iv) to establish syphilis/HIV co-morbidity; and (v) to investigate the performance of the rapid plasma reagin (RPR) test in syphilis screening, compared with the Treponema pallidum haemagglutination (TPHA) test.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods.&lt;/strong&gt; Psychiatric inpatients at Weskoppies Hospital, Pretoria, who consented to participate in the study (N=195) were categorised according to gender and length of admission (long-term or recent). Non-treponemal RPR, confirmatory TPHA, HIV-rapid and HIV enzyme-linked immunosorbent assay (ELISA) tests were performed. A reactive TPHA test was used to diagnose syphilis.&lt;/p&gt;&lt;p&gt;&lt;strong&gt; Results.&lt;/strong&gt; The estimated prevalence of syphilis was 11.7%. There was no significant association between TPHA sero-positivity and primary psychiatric diagnosis or self-reported high-risk sexual behaviour. Significant co-morbidity existed between syphilis and HIV (p=0.012). Compared with the TPHA test, the RPR test performed poorly, identifying only 2/23 patients who had a sero-positive TPHA test (8.7% sensitivity and 100% specificity).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions.&lt;/strong&gt; The prevalence of syphilis was higher than anticipated, supporting the need for routine testing. The significant co-morbidity and alarming prevalence of HIV and syphilis warrant testing for both conditions in all psychiatric admissions. Current syphilis screening with a single RPR test is inadequate; both RPR and TPHA tests should be performed.&lt;/p&gt;

The Performance of 5 Rapid HIV Tests Using Whole Blood in Infants and Children

Rapid tests have the potential to improve the identification of HIV-infected children in resource-limited settings. However, they remain underutilized because of a lack of data on their performance in the field using whole blood specimens. This study aimed to assess the accuracy of rapid tests for detecting HIV exposure, excluding HIV infection in HIV-exposed infants, and diagnosing HIV infection in children older than 18 months of age. Five rapid tests (First Response, Pareekshak, Determine, Smart Check, and Insti) were performed using whole blood from children enrolled in a multisite, cross-sectional study in South Africa. HIV enzyme-linked immunosorbent assay and DNA polymerase chain reaction results defined HIV exposure and infection, respectively, and were the standards used for comparison. Of the 851 children enrolled, 186 (21.9%) were infected with HIV. For detecting HIV exposure, Determine demonstrated the highest sensitivity of 99.3% (95% confidence interval, 98.0-99.8) in early infancy, but sensitivity declined with age as seroreversion occurred. After 8 months of age, all tests except First Response excluded HIV infection in 82% to 100% of HIV-uninfected infants and, in conjunction with a clinical assessment, did not miss any HIV-infected children. Insti was the only test that detected all HIV-infected infants, albeit on the smallest number of samples. The performance of all rapid tests in children older than 18 months of age was similar to that in adults. Determine was the only rapid test that had a high enough sensitivity for detecting HIV exposure in early infancy, but it identified seroreversion later in life than the other tests. Insti warrants further investigation for both indications.

False negative HIV antibody test in HIV infected children who receive early antiretroviral treatment in a resource-limited setting

&lt;p&gt;With the implementation of 2010 World Health Organization guidelines, the number of infants from developing countries who will initiate antiretroviral therapy (ART) will increase considerably. In this study we describe the HIV antibody tests of 14 HIV infected children who initiated ART at age less than one year in a rural setting of India. The HIV rapid test was negative in seven and indeterminate in two cases, whereas the HIV enzyme-linked immunosorbent assay (ELISA) antibody test was negative in three and indeterminate in one case. In one child who had both negative HIV rapid test and ELISA initially, HIV serology turned positive after having a virological failure to ART, suggesting the possibility of utilizing HIV serology for monitoring ART effectiveness in children who experience HIV seroreversion. In conclusion, HIV seroreversion of children with early initiation of ART is common and should be considered for avoiding misdiagnosis of HIV infection.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;

False negative HIV antibody test in HIV infected children who receive early antiretroviral treatment in a resource-limited setting

With the implementation of 2010 World Health Organization guidelines, the number of infants from developing countries who will initiate antiretroviral therapy (ART) will increase considerably. In this study we describe the HIV antibody tests of 14 HIV infected children who initiated ART at age less than one year in a rural setting of India. The HIV rapid test was negative in seven and indeterminate in two cases, whereas the HIV enzyme-linked immunosorbent assay (ELISA) antibody test was negative in three and indeterminate in one case. In one child who had both negative HIV rapid test and ELISA initially, HIV serology turned positive after having a virological failure to ART, suggesting the possibility of utilizing HIV serology for monitoring ART effectiveness in children who experience HIV seroreversion. In conclusion, HIV seroreversion of children with early initiation of ART is common and should be considered for avoiding misdiagnosis of HIV infection.

Successful treatment of bilateral visual loss caused by HIV-associated optic neuritis

Optic neuritis is not an uncommon diagnosis in HIV-infected patients, but it is rarely idiopathic. We report a case of a young HIV-infected woman who developed optic neuritis as her presenting manifestation of HIV infection. She had initially experienced sudden-onset right-sided painful visual loss; the left eye had become involved within days. Bilateral swollen discs were apparent on fundoscopy. Investigations were performed for meningitis (including bacterial, cryptococcal, tuberculous and syphilitic types), auto-immune diseases, toxoplasma, rubella, cytomegalovirus, viral hepatitis, HTLV-1/2, HIV-1/2 and syphilis. The only positive result was a reactive HIV enzyme-linked immunosorbent assay. The CD4 count was 85 cells/µl. A post-contrast magnetic resonance imaging scan of the brain illustrated enhancement of the optic nerves. Treatment was 3 days of intravenous methylprednisolone 1 g daily, followed by 11 days of oral prednisone 60 mg daily. Highly active antiretroviral therapy was initiated after 2 weeks. Vision improved from day 6 after commencement of steroid therapy, with ongoing recovery at 5 months.

Acute Dengue Fever Causes False-Positive Reactivity in OraQuick Rapid HIV-1/2 Antibody Test

To the Editors: The OraQuick ADVANCE Rapid HIV-1/2 Antibody Test, from OraSure Technologies Inc., detects antibodies to HIV-1 and HIV-2 in 20 minutes. This immunoassay can be performed on oral fluid, fingerstick whole blood, venipuncture whole blood, and plasma specimens. The manufacturer reports a sensitivity of 99.3% (95% confidence interval: = 98.4% to 99.7%) and specificity of 99.8% (95% confidence interval: = 99.6% to 99.9%) for use of the test with oral fluid specimens.1 However, false-positive results have been detected, including in test kits close to the expiration date. One study found a false-positive rate of 1.17% in test kits used with ≤1 month remaining until expiration.2 It is noted that these results came from an older version of the OraQuick ADVANCE test kit. Accuracy of both oral and blood HIV screening tests may also be affected by concomitant tropical infections. In sub-Saharan Africa, false-positive HIV enzyme-linked immunosorbent assay (ELISA) results were associated with a diagnosis of human African trypanosomiasis,3 urinary schistosomiasis,4 uncomplicated malaria,5 and visceral leishmaniasis.6 These false-positive results in HIV antibody detection testing have been attributed to polyclonal B-cell activation and/or high concentration of rheumatoid factor-like anti-immunoglobulin antibodies seen in these infections.3-6 In Colombia, 1 study postulated that parasitic proteins similar to the reverse transcriptase could be a possible cause of false positive HIV ELISA tests in patients infected by Trypanosoma cruzi.7 Since December 2008, we have been using the OraQuick test kit on oral fluid as part of a study in the Duke University Hospital Emergency Department to determine whether rapid HIV testing can be effectively offered and accepted as a routine screening test. Recently, a false-positive result occurred in a patient presenting with acute Dengue fever. The patient had just returned to the United States after traveling abroad to the island of Guadeloupe, French West Indies, for 3 weeks where she recalled receiving multiple mosquito bites. She was admitted to Duke University Hospital after presenting to the Emergency Department with acute HIV-like symptoms of recurrent fevers, night sweats, nausea, vomiting, headache, joint aches, and rash. Her initial temperature was 37.3°C, but she reported fevers up to 39.4°C at home. The patient had an erythematous, raised, nonpruritic maculopapular rash on her lower extremities. Upon presentation, her white blood cells was low at 1600 cells × 109/L with an absolute lymphocyte count of 500. Her platelets were low at 88 × 109/L and ultimately dropped to 47 during her hospitalization. Her aspartate aminotransferase was slightly elevated at 77 U/L. In Guadeloupe, she had serologies drawn, which were positive for Dengue. Acute and convalescent serologies drawn at Duke were sent to the North Carolina State Laboratory and also confirmed to be positive. As there are no reports of malaria in Guadeloupe,8 a blood smear was not performed. Her initial and repeat OraQuick oral swabs were positive. The patient denied any recent high-risk behaviors that would place her at risk for acute HIV infection and had tested negative for HIV 2 years ago. As part of our protocol for confirmation of a preliminary reactive test, a Western Blot was performed which was indeterminate with a faint band at p24. Further workup demonstrated a negative serum HIV ELISA and an undetectable HIV viral load. Although both OraQuick tests used had expiration dates ≤1 month from time of use, it is not clear if this was a contributing factor as we were using the newer version of the kit. More likely, the diagnosis of acute Dengue contributed to the false-positive result. There is only one other report documenting HIV-1 false-positive rapid ELISA tests in patients with Dengue fever.9 In this study, false-positive HIV screening tests on sera occurred in 4 of the 9 patients with Dengue, though there was no information on the mechanism by which Dengue infection triggered the false-positive reactivity. Our findings indicate that false positives may occur with rapid HIV assays, particularly in the case of concomitant infections. This may be a greater concern in resource-poor regions where diseases such as Dengue are most prevalent and as rapid HIV tests become more widely used. Alice Mao Chidera Obi-Gwacham Tamsey Hill, DMin Catherine Ryan, MSHSA Arthur Hendricks, MDiv Mehri McKellar, MD Division of Infectious Diseases and Department of Medicine, Duke University Durham, NC

Can Oral Fluid Testing Be Used to Replace Blood-Based HIV Rapid Testing to Improve Access to Diagnosis in South Africa?

Can Oral Fluid Testing Be Used to Replace Blood-Based HIV Rapid Testing to Improve Access to Diagnosis in South Africa?

The Structure and Outcomes of a HIV Postexposure Prophylaxis Program in a High HIV Prevalence Setup in Western Kenya

In 2001, HIV postexposure prophylaxis (PEP) was initiated in western Kenya. Design, implementation, and evolution of the PEP program are described. Patient data were analyzed for reasons, time to initiation, and PEP outcome. Occupational PEP was initiated first followed by nonoccupational PEP (nPEP). Antiretroviral regimens were based upon national PEP guidelines, affordability and availability, and prevailing HIV prevalence. Emerging side effects data and cost improvements influenced regimen changes. Between November 2001 and December 2006, 446 patients sought PEP. Occupational exposure: 91 patients: 51 males; 72 accepted HIV testing; 48 of 52 source patients were HIV infected; median exposure-PEP time 3 hours (range: 0.3-96 hours). Of 72 HIV-negative patients receiving PEP, 3 discontinued, 69 completed, and 23 performed post-PEP HIV RNA polymerase chain reaction (all negative). Eleven follow-up HIV enzyme-linked immunosorbent assay tests have all turned negative. Nonoccupational exposure: 355 patients; 285 females; 90 children; 300 accepted HIV testing; median exposure-nPEP time 19 hours (range: 1-672 hours). Of 296 HIV-negative patients on nPEP, 1 died, 15 discontinued, 104 are on record having completed PEP, and 129 returned for 6-week HIV RNA polymerase chain reaction (1 patient tested positive). Eighty-seven follow-up HIV enzyme-linked immunosorbent assay tests have all turned negative. It is feasible to provide PEP and nPEP in resource-constrained settings.

Seroprevalence of HIV infection in hospitalized paediatric patients at a tertiary care centre in western India

The prevalence of HIV infection in children in India is not known. In this study, a total of 270 children admitted to paediatric wards in Mumbai were screened for HIV infection by enzyme-linked immunosorbent assay (ELISA). Eight patients (2.96%) had a positive HIV ELISA. Of these two patients (25%) were less than 15 months of old and hence HIV infection in them could not be confirmed. The prevalence of HIV was 2.3%. Three out of 11 patients with tuberculosis (27.3%) and four out of 15 patients with nutritional anaemia (26.7%) had HIV infection (P<0.0001 in each case). Vertical transmission was the cause in all children, suggesting that implementation of Prevention of Parent to Child Transmission of HIV (PPTCT) is required to reduce the rate of paediatric HIV infection.

Utilizing nucleic acid amplification to identify acute HIV infection

Utilizing nucleic acid amplification to identify acute HIV infection

HIV infection in hospitalized children with endemic diseases in Abakaliki, Nigeria: the role of clinically directed selective screening in diagnosis

The increasing prevalence of HIV infection in Nigeria, its similar manifestations with endemic diseases and limited facilities for screening calls for judicious HIV testing. Children aged one month to 15 years admitted into the paediatric ward of the Ebonyi State University Teaching Hospital between January 2000 and September 2001 for various endemic diseases were reviewed retrospectively. Eight clinical risk factors commonly associated with HIV infection and endemic diseases present either singly or in combination, were reviewed to determine whether they could help to predict HIV infection and at what level and finally help formulate criteria for selective screening of HIV infection. Children above 18 months of age were diagnosed as being infected with HIV if they tested positive by two different HIV enzyme-linked immunosorbent assay (ELISA) tests. In children less than 18 months of age the diagnosis of HIV infection was made if they were ELISA positive and also fulfilled the WHO criteria for symptomatic HIV infection. Of the 282 children reviewed 31 (11.0%) were HIV positive giving a sero-prevalence rate of 4.1% of total admission. The HIV seropositive rate was highest in oral candidiasis (OC) (38.2%), followed by severe malnutrition (SM) (33.8%) then generalized lymphadenopathy (GLN) (31.4%).The presence of SM, GLN, OC and chronic dermatitis were highly significant independent risk factors for predicting HIV seropositivity (p<0.05). A marked shift towards the likelihood of HIV sero-positivity in the presence of at least two of the eight risk factors was documented. Children with two risk factors present had a 9.1 times more risk of being HIV sero-positive compared with those who had only one risk factor present (χ2=11.6, p=0.0007, OR = 9.1, 95% Cl = 2.5–32.8). Thirteen children (41.9%) representing a vast majority of HIV-positive children showed evidence of at least two of the eight clinical risk factors. As the number of risk factors concomitantly present increased, the chances of the child being infected with HIV also increase significantly (p<0.0001). Our study shows that clinically-directed selective screening in the presence of at least two risk factors should be carried out which does have a practical role in early diagnosis of HIV infection in a resource-poor setting.

A serological screening assay of human immunodeficiency virus type 1 antibodies based on recombinant protein p24–gp41 as a fusion protein expressed in Escherichia coli

The objective of this study was expression of a recombinant fusion protein p24-gp41 to gain a proper folding pattern of the proteins which could be recognized by specific antibodies against human immunodeficiency virus type 1 (HIV-1) for development of a reliable serodiagnostic kit. Serodiagnostic method using enzyme-linked immunosorbent assay (ELISA) with the expressed recombinant fusion protein p24-gp41 was carried out to test the sensitivity and specificity of the protein using human sera and various reference panels from Boston Biomedica Inc. (BBI). The level of the expression was determined to be 30% and the final recovery from fermentation and purification process was calculated as 80 mg/L with more than 98% purity. The developed ELISA assay was demonstrated to have 100 and 99.5% sensitivity and specificity, respectively, detecting anti-HIV-1 antibody using 900 positive and 10,000 negative human sera. The developed assay showed reliable results in comparison with other reference HIV ELISA kits using various BBI panels as well. In conclusion, the recombinant fusion protein p24-gp41 was expressed and used to develop a serodiagnostic kit for screening of the HIV-1 with high sensitivity (100%) and specificity (99.5%) which could be useful for screening large groups of blood donors.

Seasonal variation in undiagnosed HIV infection on the general medicine and trauma services of two urban hospitals

To examine the seroprevalence of undiagnosed HIV and variation by season among patients admitted to the general internal medicine (GIM) and trauma services of two urban hospitals. A cross-sectional blinded HIV-1 seroprevalence survey. A 725-bed academic medical center's hospital and an affiliated 324-bed tertiary care hospital. Residual serological specimens were obtained for unique patients aged 17 to 65 to study services in summer (June 16 to September 4, 2001) and fall to winter (November 1, 2001 to January 8, 2002). Hospital files provided data on demographics, service type, and discharge clinical categories (fall-winter group only). HIV ELISA (enzyme-linked immunosorbent assay) tests with confirmatory Western blot were linked to subjects' de-identified files. We excluded 34 subjects with known HIV. Of the remaining unique admissions in summer (n=604) and fall-winter (n=978), 60% and 55% were tested, respectively. Predictors of undiagnosed HIV infection were examined using multivariate analysis. The summer cohort (n=362) had significantly lower unadjusted seroprevalence of undiagnosed HIV infection (1.4%; 95% confidence interval [CI], 0.4% to 3.2%) than the fall-winter cohort (n=539; 3.7%; 95% CI, 2.3% to 5.7%; P=.04). Overall, undiagnosed HIV was somewhat less likely in women (adjusted odds ratio [AOR], 0.45; 95% CI, 0.19 to 1.07) but more likely in black patients (AOR, 3.46; 95% CI, 0.70 to 17.06). In the fall-winter cohort, undiagnosed HIV was more likely for discharges with the following clinical categories versus those with a cardiac condition: dermatologic/breast (AOR, 14.90; 95% CI, 1.20 to 184.77), renal/urological (AOR, 22.43; 95% CI, 2.12 to 236.75), or infectious (AOR, 31.08; 95% CI, 2.40 to 402.98). The higher seroprevalence of undiagnosed HIV in the fall-winter admissions to GIM and trauma services supports especially targeting HIV testing in these months.

Incomplete HIV Type 1 Antibody Evolution and Seroreversion in Acutely Infected Individuals Treated with Early Antiretroviral Therapy

The diagnosis of human immunodeficiency virus type 1 (HIV-1) infection by standard tests relies on the formation of HIV-1-specific antibodies. Early treatment of acute HIV-1 infection may have unique immunologic effects on host cellular and humoral responses. Rare cases of HIV-1 seroreversion have been reported for patients with advanced or rapidly progressive disease. Here, we report seroreversion that occurred in subjects with acute HIV-1 infection who initiated early antiretroviral therapy. A total of 150 patients with symptomatic acute or early onset HIV-1 infection that was treated with antiretroviral therapy were observed prospectively by means of monthly clinical and laboratory evaluation, which included serial HIV enzyme-linked immunosorbent assay and Western blots, until a fully evolved HIV-1 antibody response was documented. Three patients who initiated antiretroviral therapy a mean interval of 8 days (range, 1-16 days) after presentation and were observed for a mean duration of 50.2 months (range, 40.2-55.7 months) did not develop a fully evolved HIV-1 antibody response or demonstrated complete or partial HIV-1 seroreversion, despite maintenance of cytomegalovirus-specific humoral responses. Virologic suppression and seroreversion (complete or partial) occurred a mean duration of 4.1 months (range, 2.3-5.7 months) and 15.5 months (range, 6.7-26.3 months), respectively, after the initiation of therapy. All patients maintained complete virologic suppression while receiving therapy and had an undetectable HIV-1 RNA load at the time of seroreversion. Early antiretroviral therapy associated with durable virologic suppression in acute HIV-1 infection may abrogate the formation or detection of HIV-1-specific antibodies. Ongoing antigenic stimulation may be required to maintain HIV-1-specific humoral responses. Incomplete evolution of the HIV-1 antibody response and/or presence of seroreversion (although infrequently observed) underscore the potential unique immunologic effect of early antiretroviral therapy in patients with primary HIV-1 infection.