Hepatitis C and blood transfusion among children attending the Sickle Cell Clinic at Mulago Hospital, Uganda

BACKGROUND

Hepatitis C virus (HCV) accounts for 90% of post-transfusion hepatitis. In Uganda, there has been limited research of prevalence of HCV among sickle cell anaemia (SS) patients, a group at risk for multiple transfusions.

OBJECTIVES

To establish prevalence of HCV infection and determine whether blood transfusion increases risk among SS patients.

METHODS

244 SS patients aged 1-18 years were recruited by consecutive sampling. Socio-demographic, clinical and transfusion history was collected. Clinical examination done and blood tested for HCV by MEIA.

RESULTS

244 children were recruited. Of these, 159 (65%) had a history of blood transfusion. Among the transfused, five patients were HCV positive. Four of these were over 12 years of age. Among patients with no history of transfusion, one patient aged 14 years was HCV positive. Risk of HCV was higher among the transfused OR 2.7(CI 0.31-24). Patients who received more than two units were more likely to be HCV positive (p=0.03).

CONCLUSIONS

HCV prevalence of 2.5% was low but higher than that reported by other investigators in Uganda. Blood transfusion was a major contributing factor in occurrence of HCV. Children who get repeated transfusions should be screened for Hepatitis C and screening of blood for HCV prior to transfusion would help reduce occurrence of the disease.

Homozygous sickle cell disease in Uganda and Jamaica a comparison of Bantu and Benin haplotypes

OBJECTIVE

To compare the haematological and clinical features of homozygous sickle cell (SS) disease in Bantu and Benin haplotypes in a cross-sectional study of 115 Ugandan patients attending the Sickle Cell Clinic at Mulago Hospital, Kampala, Uganda, with 311 patients in the Jamaican Cohort Study

METHODS

This involved comparison of clinical features and haematology with special reference to genetic determinants of severity including fetal haemoglobin levels, beta-globin haplotype and alpha thalassaemia status.

RESULTS

The Bantu haplotype accounted for 94% of HbS chromosomes in Ugandan patients and the Benin haplotype for 76% of HbS chromosomes in Jamaica. Ugandan patients were marginally more likely to have alpha thalassaemia, had similar total haemoglobin and fetal haemoglobin levels but had higher reticulocyte counts and total bilirubin levels consistent with greater haemolysis. Ugandan patients had less leg ulceration and priapism, but the mode of clinical presentation, prevalence of dactylitis, features of bone pain and degree of delay in sexual development, assessed by menarche, were similar in the groups. In Ugandan patients, a history of anaemic episodes was common but these were poorly documented.

CONCLUSION

The haematological and clinical features of the Bantu haplotype in Uganda were broadly similar to the Benin haplotype in Jamaica except for less leg ulceration and priapism and possibly greater haemolysis among Ugandan subjects. Anaemic episodes in Uganda were treated empirically by transfusion often without a clear diagnosis; better documentation including reticulocyte counts and observations on spleen size is necessary to evolve appropriate models of care.

Bacteraemia in homozygous sickle cell disease in Africa: is pneumococcal prophylaxis justified?

BACKGROUND

The high frequency of Streptococcus pneumoniae as a cause of bacteraemia in homozygous sickle cell (SS) disease and its effective prevention has led to the routine use of pneumococcal prophylaxis in developed countries. The reported infrequency of this organism as a cause of bacteraemia in SS disease in Africa raises questions on the epidemiology of bacterial infection and on the need for pneumococcal prophylaxis in that continent.

METHODS

A study of blood cultures in 155 Ugandan children (165 episodes) with SS disease and axillary temperatures of > or =38 degrees C, attending the University Teaching Hospital in Kampala (Uganda, East Africa).

RESULTS

Positive blood cultures, obtained in 47/165 episodes, showed Staphylococcus aureus in 28 (60%) samples, Haemophilus influenzae in 9 (19%), Staphylococcus epidermidis in 4 (9%), and single cases of Streptococcus viridans, Escherichia coli and an unidentified Gram negative rod. Streptococcus pneumoniae was identified in only 3 (6%) episode.

CONCLUSION

The infrequent isolation of Streptococcus pneumoniae from febrile children with SS disease in this study and in four other studies from Nigeria raises questions on a different spectrum of bacterial causes for bacteraemia in malarial areas. There are several possible explanations for this finding, but the data cast sufficient doubt on the case for pneumococcal prophylaxis for a controlled trial on its effectiveness in that environment to seem justified. These data are necessary to determine its role in African children and to provide the evidence base for healthcare authorities in equatorial Africa.

Risk factors and cumulative incidence of anaemia among human immunodeficiency virus-infected children in Uganda

Anaemia has not been well characterised among HIV-infected children in sub-Saharan Africa. Baseline prevalence and cumulative incidence of anaemia (haemoglobin < 110 g/L) were 91.7% and 100% and, for moderate anaemia (haemoglobin < 90 g/L), were 35.1% and 58.4%, respectively, among 225 HIV-infected children followed from 9 to 36 months of age. Hospitalisation, suspected tuberculosis, malaria and height-for-age Z-score <-2 were significantly associated with moderate anaemia. Moderate anaemia and weight-for-height Z-score <-2 were associated with mortality. Anaemia is common and associated with increased mortality in HIV-infected children.

Relation of vitamin A and carotenoid status to growth failure and mortality among Ugandan infants with human immunodeficiency virus

Although growth failure is common during pediatric infection with human immunodeficiency virus (HIV) and associated with increased mortality, the relation of specific nutrition factors with growth and mortality has not been well characterized. A longitudinal study was conducted with 194 HIV-infected infants in Kampala, Uganda. Plasma vitamin A, carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin), and vitamin E were measured at age 14 wk, and weight and height were followed up to age 12 mo. Vitamin A and low plasma carotenoid concentrations were predictive of decreased weight and height velocity. Between ages 14 wk and 12 mo, 32% of infants died. Underweight, stunting, and low concentrations of plasma carotenoids were associated with increased risk of death in univariate analyses. Plasma vitamin A concentrations were not associated with risk of death. In a final multivariate model adjusting for weight-for-age, plasma beta-carotene was significantly associated with increased mortality (odds ratio: 3.16, 95% confidence interval: 1.38 to 7.21, P < 0.006). These data suggest that low concentrations of plasma carotenoids are associated with increased risk of death during HIV infection among infants in Uganda.

HIV-1 ICD p24 antigen detection in ugandan infants: use in early diagnosis of infection and as a marker of disease progression

The objective of this study was to determine the use of immune-complex dissociated (ICD) p24 antigen detection for the diagnosis and prognosis of HIV-1 infection in Ugandan children. Plasma collected prospectively from children born to HIV-1 infected Ugandan women was stored and later analyzed for the presence of neutralizable HIV-1 p24 antigen using the Coulter ICD p24 antigen and neutralization kits. HIV-1 infection status, disease progression, and survival of the children were determined. Specimens from 311 children born to HIV-1 infected women, including 138 HIV-1 infected children, and 113 children born to negative women were tested. Sixty-nine (50%) infected children were p24 antigen positive at least once. For early HIV-1 diagnosis, the specificity and positive predictive value of the assay were consistently high (>95% and >83% respectively), but the sensitivity was low (6-53%), especially in the first months of life. The presence of p24 antigenemia in the first two years of life was associated with poor survival (20%) by 80 months of age compared with infected children without antigenemia (43%, P < 0.001). Early detection of p24 antigen (</=2 months) was associated with higher mortality than first detection at an older age (>6 months, P < 0.001). The data suggest that ICD p24 antigen detection is not a sensitive method for the determination of infant HIV-1 status in our cohort of HIV-1 infected Ugandan children tested in the first two years of life. There was a strong correlation, however, between the presence and time of onset of p24 antigenemia and mortality among HIV-1 infected children.

Measles infection in HIV-infected African infants

Measles infection remains a serious threat to child survival in the developing world despite vaccination and treatment with vitamin A. This report reviews the epidemiology of measles in HIV-infected children in Africa. In hospitalized infants, the rate of malnutrition before measles and the rate of death after measles are both higher in HIV-positive than in HIV-negative infants. However, the rates of pneumonia and diarrhea in infants hospitalized with measles are the same in HIV-positive as in HIV-negative infants. In an autopsy study, measles was associated with death in HIV-positive children, only for those over 15 months of age. A cohort study found that infants of HIV-positive women were more likely than infants of HIV-negative women to have measles before 9 months of age, although the rates of complications did not differ between the two groups. The HIV status of the infants and the measles serology were too incomplete to draw firm conclusions, though only 1 of 54 infants tested was seropositive for measles at 6 months of age. In the context of the HIV epidemic, further work is needed to determine the risk of measles and its complications in HIV-positive infants and the optimal age of measles immunization.

Identification of diverse HIV type 1 subtypes and dual HIV type 1 infection in pregnant Ugandan women

Vertical (mother-to-child) transmission accounts for the majority of pediatric HIV-1 infections. Many factors are involved in vertical transmission, however it is not clear which factors are most important for determining whether a mother will transmit HIV-1 to her infant. It has been suggested that HIV-1 subtype may influence vertical transmission and that subtype D viruses may be less likely to be transmitted in this setting. We analyzed HIV-1 gp120 V3 region sequences from the plasma of 20 pregnant Ugandan women of known transmission status who did not receive antiretroviral prophylaxis. V3 regions were cloned, sequenced, and subtyped by phylogenetic analysis. Among 11 women who transmitted HIV-1 to their infants, we detected subtypes A, C, D, and G. Two of the transmitters had dual infection with subtypes A and D. In addition, a third was infected with two distinct strains of subtype G viruses. HIV-1 subtype A and D viruses were found in 9 women who did not transmit the virus to their infants. This study reveals that pregnant Ugandan women harbor diverse HIV-1 subtypes, including women who transmit HIV-1 to their infants. Transmission of HIV-1 with subtype D V3 regions was confirmed in 4 of the 11 transmitters, including 2 who had dual infection with subtype A and D HIV-1.

Placental membrane inflammation and risks of maternal-to-child transmission of HIV-1 in Uganda

Prospective follow-up of 172 HIV-infected pregnant women and their infants was conducted at Mulago Hospital, Kampala, Uganda during 1990 to 1992. Information was collected on maternal immune status (CD4 counts or clinical AIDS), and concurrent infections with sexually transmitted diseases. Infants were observed on a follow-up basis to determine HIV infection, using polymerase chain reaction (PCR) under 15 months of age and enzyme immunoassay/Western blot for those older than 15 months. Placental membrane inflammation (chorioamnionitis and funisitis), and placental villous inflammation (villitis, intervillitis, and deciduitis) were diagnosed by histopathology. Mother-to-child HIV transmission rates were assessed, and adjusted odds ratios (OR) and 95% confidence intervals (95% CI) of transmission were estimated using women with no placental pathology or evidence of immune suppression as a reference group.

RESULTS

The overall mother-to-child HIV transmission rate was 23.3%. Women with no placental membrane inflammation or immune suppression had a transmission rate of 11.3%; compared with 25.5% in women with placental inflammation and no immunosuppression (adjusted OR, 2.87; 95% CI, 1.04-7.90), and 37.0% in immunosuppressed women (OR, 3.07; 95% CI, 1.42-6.67). We estimate that 34% of HIV transmission could be prevented by treatment of placental membrane inflammation in nonimmunocompromised women. Transmission rates were 40.9% with genital ulcer disease (OR, 3.57; 95% CI, 1.28-9.66). Placental villous inflammation and artificial rupture of membranes did not increase transmission rates and cesarean section was associated with a nonsignificant reduction of risk (OR, 0.70; 95% CI 0.24-2.06).

CONCLUSION

Placental membrane inflammation increases the rate of mother-to-child HIV transmission.

Neurodevelopmental outcomes of Ugandan infants with HIV infection: an application of growth curve analysis

Neurodevelopmental outcomes of human immunodeficiency virus Type 1 (HIV-1)-infected infants of non-drug-using mothers were assessed in a controlled, prospective study from birth to 24 months with 3 groups: 61 infants of HIV-infected mothers, 234 uninfected infants of HIV-infected mothers (seroreverters), and 115 uninfected infants of uninfected mothers. Compared with seroreverters and uninfected infants, HIV-infected infants demonstrated lower mental and motor development on the Bayley Scales and greater deceleration in their rate of motor development. HIV-infected infants with abnormal neurologic exams had lower motor and mental test scores and lower rates of motor Bayley Scales scores than their HIV-infected counterparts with normal neurologic exams. Contrary to prediction, no group differences in mean performance or growth rates were found on visual information processing on the Fagan Test of Infant Intelligence.

Neurodevelopmental outcomes of Ugandan infants with HIV infection: an application of growth curve analysis

Neurodevelopmental outcomes of human immunodeficiency virus Type 1 (HIV-1)-infected infants of non-drug-using mothers were assessed in a controlled, prospective study from birth to 24 months with 3 groups: 61 infants of HIV-infected mothers, 234 uninfected infants of HIV-infected mothers (seroreverters), and 115 uninfected infants of uninfected mothers. Compared with seroreverters and uninfected infants, HIV-infected infants demonstrated lower mental and motor development on the Bayley Scales and greater deceleration in their rate of motor development. HIV-infected infants with abnormal neurologic exams had lower motor and mental test scores and lower rates of motor Bayley Scales scores than their HIV-infected counterparts with normal neurologic exams. Contrary to prediction, no group differences in mean performance or growth rates were found on visual information processing on the Fagan Test of Infant Intelligence.

Effects of malaria infection in human immunodeficiency virus type 1-infected Ugandan children

BACKGROUND

Malaria causes severe morbidity and mortality in many areas of Africa where HIV-1 infection is also prevalent. Immunosuppression is associated with both diseases but most reports do not find significant interactions between them.

METHODS

A collaborative study of HIV-1 infection in Ugandan women and their infants was established between the Ministry of Health, Makerere University, Kampala, and Case Western Reserve University in 1988. Four hundred fifty-eight infants, including 77 HIV-1-infected, 232 seroreverter and 125 control children born to HIV-1-negative mothers and 24 of indeterminate status were followed closely from birth for 4 years. Data on these infants were reviewed with respect to episodes of general illness and infections, suspected and confirmed episodes of malaria, onset and frequency of malaria, use of chloroquine and occurrence of selected illnesses after episodes of febrile illnesses. Thick and thin blood smears for malaria were obtained from children with fever.

RESULTS

There was no association between occurrence of febrile illnesses and childrens' HIV-1 category. The relative rates of occurrence were 1.0 (95% confidence interval (CI), 0.8 to 1.2) and 1.1 (95% CI 0.9 to 1.4) for the HIV seroreverter and control children compared with the HIV-infected children. Although there was no association (P = 0.83) between HIV-1 status and a smear being taken during a febrile episode, there was an increase in smears positive for malaria parasitemia among seroreverter (risk ratio, 1.5; 95% CI 1.1 to 1.9) and control infants (risk ratio, 1.6; 95% CI 1.2 to 2.2) compared with HIV-1-infected infants. The level of parasitemia was similar in each group. A greater proportion of malaria episodes among the HIV-infected group than among the control groups resulted in hospitalizations (P = 0.001) and blood transfusions (P = 0.02). There was a positive association between time to clinical AIDS and absence of malaria (adjusted for follow-up age) in infected children (P = 0.02). Use of chloroquine was similarly high in each HIV-1 category (80%).

CONCLUSIONS

In this group of HIV-infected children there was no significant increase in malarial episodes as compared with their HIV-negative controls. The results suggest a possibility that malaria may offer some protection against HIV-1 progression or that chloroquine used to treat malaria may have a direct effect against the HIV-1 virus.

Neurodevelopmental outcomes of Ugandan infants with human immunodeficiency virus type 1 infection

BACKGROUND

The neurodevelopmental outcomes of human immunodeficiency virus type 1 (HIV-1)-infected Ugandan infants of nondrug-using mothers were studied using controlled, prospective methodology.

METHOD

The sample of 436 full-term infants included 79 HIV-infected infants of HIV-1-infected mothers, 241 uninfected infants of HIV-1-infected mothers (seroreverters), and 116 uninfected infants born to HIV-negative mothers. Neurologic status, information processing ability, and motor and mental development were assessed from 6 to 24 months of age. Observations of caretaker-child interaction and home environments were made at 6 and 12 months. All evaluators were blinded to the HIV status of the child and family.

RESULTS

Compared with seroreverters and uninfected infants, HIV-infected infants demonstrated greater deficits in motor development and neurologic status, and more frequent and earlier onset of motor and neurologic abnormalities. Compared with controls, HIV-infected infants had more abnormalities in mental development at 6 and 18 months and an earlier onset of abnormalities. By 12 months, 30% of HIV-infected infants demonstrated motor abnormalities and 26% cognitive abnormalities as compared with 11% and 6% among seroreverters and 5% and 6% among seronegative infants. HIV-infected infants (62%) demonstrated a higher probability of developing an abnormal neurologic examination by 12 months, compared with seroreverters (17%) or seronegative infants (15%). Information-processing abilities did not differ as a function of HIV infection. Home environments and infants' interactions with caretakers were similar across groups.

CONCLUSION

We conclude that HIV infection results in more frequent and earlier abnormalities in infants' neurologic status and motor development that are not attributable to other biological and environmental risk factors. More frequent mental developmental abnormalities were evident at several ages. However, information-processing abilities, such as recognition memory, may be spared from HIV-related deficits.

Growth failure as a prognostic indicator of mortality in pediatric HIV infection

OBJECTIVE

To study the effect of perinatally acquired human immunodeficiency virus (HIV) on somatic growth and examine the relationship of nutritional status to mortality in HIV-infected infants.

METHOD

Pregnant women attending the antenatal clinic at Mulago hospital in Kampala, Uganda, were enrolled. All live-born babies born to HIV-1 seropositive (HIV+) women, and to every fourth age-matched HIV-1 seronegative (HIV-) woman, were followed for 25 months.

RESULTS

The mean weight-for-age and length-for-age curves of HIV+ children were significantly lower than those of HIV- controls and seroeverters. Forty-five (54%) of the 84 HIV+ infants died before their second birthday, as compared with a 1.6% and 5.6% mortality in HIV- and seroeverters. HIV+ infants with an average weight-for-age Z-score below -1.5 in the first year of life have a nearly fivefold risk of dying before 25 months of age compared with noninfected controls.

CONCLUSION

Perinatally acquired HIV infection is associated with early and progressive growth failure. The severity of growth failure is associated with an increased risk of mortality. The effect of early, aggressive nutritional intervention in delaying HIV progression and mortality should be evaluated by controlled intervention studies.

Detection of human immunodeficiency virus type 1 (HIV-1) DNA and p24 antigen in breast milk of HIV-1-infected Ugandan women and vertical transmission

OBJECTIVE

To determine the correlation between the detection of human immunodeficiency virus type 1 (HIV-1) in breast milk, the duration of breastfeeding, and vertical transmission of HIV-1 infection in Ugandan women.

METHODS

A prospective study of HIV-1 infection in pregnant Ugandan women and their infants has been ongoing since 1990 with follow-up of mother-infant pairs for at least 2 years. Expressed breast milk specimens were collected from 201 HIV-1-seropositive and 86 HIV-1-seronegative Ugandan women approximately 6 weeks after delivery. The presence of HIV-1 DNA in the cellular fraction of the breast milk was detected by polymerase chain reaction (PCR), and HIV-1 p24 antigen was detected in the cell-free breast milk supernatant using p24 antigen enzyme immunoassay (EIA) after immune complex dissociation (ICD). The duration of breastfeeding and the clinical status of the mothers and their children were recorded. HIV-1 EIA, Western blot, PCR, or p24 antigen detection were used for the determination of the HIV-1 infection status of the children.

RESULTS

Of the 201 HIV-1-infected women studied, 47 had HIV-1-infected children, 143 had children who seroreverted, and 11 had children of indeterminate status. Breast milk supernatants were available for ICD p24 antigen testing from 188 of the HIV-1-infected women and none had detectable p24 antigen. Breast milk cell pellets were available and contained amplifiable DNA in 125 of the HIV-1-infected women (20 transmitters, 104 nontransmitters, 1 indeterminate). HIV-1 DNA was detected by PCR in 72% (75/104) of nontransmitters and 80% (16/20) of the transmitters. The duration of breastfeeding by transmitter mothers (15.8 months) was not significantly different from nontransmitter mothers (14.4 months).

CONCLUSIONS

No correlation was found between the detection of HIV-1 in breast milk or the duration of breastfeeding and transmission of HIV-1 infection in this study of Ugandan women.

Maternal HIV-1 RNA serum levels at delivery and vertical transmission in Uganda

OBJECTIVE

To evaluate the clinical utility of maternal HIV-1 RNA serum levels at delivery in predicting the rate of HIV-1 vertical transmission.

DESIGN AND METHODS

HIV-1 RNA levels were determined by the Roche Amplicor Monitor assay in serum specimens collected at the time of delivery from 94 transmitting and 107 nontransmitting infected mothers and 12 seronegative mothers in Uganda. Nonparametric Wilcoxon-Rank sum tests were used to identify significant differences in medians and RNA level distributions by transmission status.

RESULTS

Mean HIV-1 RNA copies/mL for transmitters was 3419 +/- 7489 copies/mL versus 2483 +/- 8954 copies/mL for nontransmitters. There was a significant difference in medians and HIV-1 RNA serum level distributions between transmitting and nontransmitting mothers (p = 0.0039). However, the predictive value for any given HIV-1 RNA level for HIV-1 vertical transmission was poor.

CONCLUSION

Maternal HIV-1 RNA serum levels at delivery are significantly higher in transmitting mothers versus nontransmitting mothers, but appear to be of limited value in predicting HIV-1 vertical transmission using the Roche Amplicor Monitor assay in Uganda.

Lack of association between anti-V3 loop antibodies and perinatal transmission of HIV-1 in Kampala, Uganda

This study evaluated the association between reactivity of maternal antibody to human immunodeficiency virus type 1 (HIV-1) V3 loop peptides and perinatal transmission in Uganda. Plasma from 40 HIV-1-infected mothers (20 transmitting and 20 nontransmitting mothers) and 31 uninfected mothers in Uganda were tested for reactivity and antibody titer to synthetic peptides representing V3 loop sequences from HIV-1 strains MN, SF2, LAI, ZR6, and CM235 and consensus peptides CA, CB, and CD. No significant differences were found between 20 transmitting mothers and 20 nontransmitting mothers in terms of percent reactivity or titer of antibody to any of the V3 loop peptides tested. Use of a multivariable logistic model to adjust for beta-2 microglobulin level as a confounding variable of stage of infection did not help demonstrate an association except possibly for the ZR6 peptide. These data suggest that neither reactivity nor maternal antibody titer to V3 loop peptides are protective against perinatal transmission of HIV-1 in Uganda.

Beta 2-microglobulin, HIV-1 p24 antibody and acid-dissociated HIV-1 p24 antigen levels: predictive markers for vertical transmission of HIV-1 in pregnant Ugandan women

OBJECTIVES

To evaluate the clinical utility of plasma beta 2-microglobulin (beta 2M) levels, acid-dissociated HIV-1 p24 antigen, and HIV-1 p24-antibody titers in predicting HIV-1 vertical transmission in 227 HIV-1-infected Ugandan pregnant women.

DESIGN

Plasma beta 2M levels, acid-dissociated HIV-1 p24-antigen positivity, and HIV-1 p24-antibody titers were determined using commercial enzyme immunoassays (EIA) in a Ugandan cohort of 52 HIV-1-seropositive transmitting mothers, 175 HIV-1-seropositive non-transmitting mothers, and 52 seronegative mothers within 6 weeks prior to delivery.

RESULTS

Transmitter mothers had significantly higher plasma concentrations of beta 2M (1.80 +/- 1.13 mg/l) than non-transmitter seropositive mothers (1.32 +/- 0.81 mg/l; P = 0.0013). Similarly, a significantly higher proportion of transmitter mothers had detectable p24 antigen than non-transmitter mothers [six out of 51 (11.8%) versus six out of 173 (3.5%); P = 0.03]. Compared with the vertical transmission rate of 23% in the seropositive group, the positive predictive values of a beta 2M level > 1.5 mg/l or detectable HIV-1 p24 antigen for vertical transmission were 34 and 50%, respectively. Five of six (83.3%) seropositive mothers with both a beta 2M level > 1.5 mg/l and detectable p24 antigenemia transmitted HIV-1 infection to their infants compared with 25 of 124 (20.2%) seropositive mothers with values below the cut-off values for both tests (P = 0.00249). However, beta 2M was not found to be a significant independent predictor of vertical transmission when analyzed in a multivariate model with p24 antigenemia. There was no significant difference in HIV-1 p24-antibody titers in transmitter mothers versus non-transmitter mothers (P = 0.299).

CONCLUSION

beta 2M levels and acid-dissociated HIV-1 p24-antigen assays may be used to predict which HIV-1-infected pregnant women are at greatest risk for vertical transmission. However, only the p24-antigen test was independently predictive of vertical transmission and its clinical utility is limited.

Non-isotopic polymerase chain reaction methods for the detection of HIV-1 in Ugandan mothers and infants

Two non-isotopic polymerase chain reaction (PCR) methods were evaluated by testing blood from 41 HIV-1-seropositive and 16 HIV-1-seronegative Ugandan mothers and 56 of their children (aged 0.5-15.0 months). Amplification of HIV-1 sequences was performed in duplicate using a biotinylated primer pair to the gag region (SK 462-431) and nested primer pairs (JA 17-20) to the pol region of HIV-1. gag sequences were hybridized using a microtiter plate coated with the SK 102 probe followed by colorimetric detection using an avidin-horseradish peroxidase conjugate and tetramethylbenzidine/peroxide substrate. pol sequences were detected on agarose gel stained with ethidium bromide. Results of HIV-1 PCR analysis showed that 40 out of 41 (98%) seropositive mothers and 10 out of 29 (34%) seropositive children had detectable HIV-1 gag and pol sequences. None of the 16 seronegative mothers nor 27 seronegative or Western blot-indeterminate children had detectable HIV-1 sequences. Our results suggest that non-isotopic PCR methods are sensitive, specific, and potentially useful in the early diagnosis of HIV-1 infection in developed and developing countries.