CD16+ monocyte subset preferentially harbors HIV-1 and is expanded in pregnant Malawian women with Plasmodium falciparum malaria and HIV-1 infection.

In a cross-sectional study, monocyte subsets in placental, cord, and maternal peripheral blood from pregnant Malawian women with human immunodeficiency virus (HIV)-1 infection and/or malaria were analyzed. HIV-uninfected Malawian women had higher baseline proportions of CD16(+) monocytes than those reported for healthy adults in developed countries. Malaria was associated with an increase in the proportion of CD16(+) monocytes that was significant in women coinfected with HIV-1. CD16(+) monocytes expressed higher CCR5 levels than did CD14(hi)/CD16(-) monocytes and were significantly more likely to harbor HIV-1. These data suggest a role for CD16(+) monocytes in the pathogenesis of maternal malaria and HIV-1 infections.

Maternal syphilis infection is associated with increased risk of mother-to-child transmission of HIV in Malawi.

OBJECTIVE: To determine the association between maternal syphilis and HIV mother-to-child transmission (MTCT). DESIGN: Prospective cohort study. METHODS: Pregnant women admitted at Queen Elizabeth Central Hospital (Malawi) in late third trimester were screened for HIV (by HIV rapid tests) and syphilis (by rapid plasma regain test and Treponema pallidum hemagglutination assay). HIV-infected women and their infants received nevirapine, according to the HIVNET 012 protocol. They were followed up at 6 and 12 weeks postpartum. Infant HIV infection was diagnosed by DNA PCR. FINDINGS: Of the 1155 HIV-infected women enrolled, 1147 had syphilis test results, of whom 92 (8.0%) were infected. Only 751 HIV-positive women delivered live singleton infants who were tested for HIV at birth. Of these, 65 (8.7%) were HIV-infected, suggesting in utero (IU) HIV MTCT. Of the 686 infants who were HIV-negative at birth, 507 were successfully followed up. Of these, 89 (17.6%) became HIV-infected, suggesting intrapartum/postpartum (IP/PP) HIV MTCT. Maternal syphilis was associated with IU HIV MTCT, after adjusting for maternal log10 HIV-1 viral load and low birth weight (LBW) [adjusted relative risk (ARR), 2.77; 95% CI, 1.40-5.46]. Furthermore, maternal syphilis was associated with IP/PP HIV MTCT (ARR, 2.74; 95% CI, 1.58-4.74), after adjusting for recent fever, breast infection, LBW and maternal log10 HIV-1 viral load. CONCLUSION: Maternal syphilis is associated with IU and IP/PP HIV MTCT. Screening and early treatment of maternal syphilis during pregnancy may reduce pediatric HIV infections.

Maternal-fetal microtransfusions and HIV-1 mother-to-child transmission in Malawi.

BACKGROUND: Between 25% and 35% of infants born to HIV-infected mothers become HIV-1 infected. One potential route of mother-to-child transmission (MTCT) could be through a breakdown in the placental barrier (i.e., maternal-fetal microtransfusions). METHODS AND FINDINGS: Placental alkaline phosphatase (PLAP) is a 130-kD maternal enzyme that cannot cross the intact placental barrier. We measured PLAP activity in umbilical vein serum as an indicator of maternal-fetal microtransfusion, and related this to the risk of HIV-1 MTCT. A case-cohort study was conducted of 149 women randomly selected from a cohort of HIV-1-infected pregnant Malawians; these women served as a reference group for 36 cases of in utero MTCT and 43 cases of intrapartum (IP) MTCT. Cord PLAP activity was measured with an immunocatalytic assay. Infant HIV status was determined by real-time PCR. The association between cord PLAP activity and HIV-1 MTCT was measured with logistic regression using generalized estimating equations. Among vaginal deliveries, PLAP was associated with IP MTCT (risk ratio, 2.25 per log10 ng/ml PLAP; 95% confidence interval, 0.95-5.32) but not in utero MTCT. In a multivariable model adjusted for HIV-1 RNA load, chorioamnionitis, and self-reported fever, the risk of IP MTCT almost tripled for every log10 increase in cord PLAP activity (risk ratio, 2.87; 95% confidence interval, 1.05-7.83). CONCLUSION: These results suggest that during vaginal deliveries, placental microtransfusions are a risk factor for IP HIV-1 MTCT. Future studies are needed to identify factors that increase the risk for microtransfusions in order to prevent IP HIV-1 MTCT.

Post term pregnancy at teaching hospitals in Addis Ababa, Ethiopia.

OBJECTIVE: To Determine pregnancy outcome between term and post term deliveries and to assess the proportion of post maturity syndrome among neonates in the two groups. DESIGN: Cross-sectional comparative study of pregnancy outcome among term and post term mothers. SETTING: Two teaching hospitals in Addis Ababa, Ethiopia. SUBJECTS: 376 post-term mothers compared to 376 term mothers. MAIN OUTCOME MEASURES: Fetal distress, caesarean section rates, neonatal intensive care unit admission, perinatal mortality, congenital anomalies, low birth weight, Apgar scores, macrosomia and third stage complications. RESULTS: The proportion of mothers delivering post term at the study sites was 8.8%, which agrees with most series in which diagnosis of post term was based on LNMP. There were 99 (26.3%) fetal distress in the post term group compared to 50 (11.2%) among term deliveries (P<0.001). The caesarean rate for the post term mothers was 89 (23.7%) compared to term mothers of 47(12.5%) (P<0.001). Neonatal intensive care unit admission rate for post term mothers was 25(6.7%) compared with 1(2.9%) term mothers (P<0.05). No significant differences in the rates of perinatal mortality, congenital anomalies, low birth weight, macrosomia, CPD or third stage complications were observed between the two groups, though most were relatively frequent in post terms. CONCLUSION: Due to lack of antenatal care and late referral, the diagnosis of post terms is based on LNMP alone in most cases. Fetal distress, perinatal asphyxia and consequent caesarean delivery rate is much higher than other series. Health education on early initiation of antenatal care as well as timely referral from peripheral units is urgently needed. Based on the findings of our study we recommend that in all pregnant women (individualization is possible) with 42 completed weeks of gestation, the pregnancy should be terminated be it through vaginal or abdominal route for a better fetal outcome.

Malaria during pregnancy and foetal haematological status in Blantyre, Malawi.

BACKGROUND: Although maternal anaemia often stems from malaria infection during pregnancy, its effects on foetal haemoglobin levels are not straightforward. Lower-than-expected cord haemoglobin values in malarious versus non-malarious regions were noted by one review, which hypothesized they resulted from foetal immune activation to maternal malaria. This study addressed this idea by examining cord haemoglobin levels in relation to maternal malaria, anaemia, and markers of foetal immune activation. METHODS: Cord haemoglobin levels were examined in 32 malaria-infected and 58 uninfected women in Blantyre, Malawi, in relation to maternal haemoglobin levels, malaria status, and markers of foetal haematological status, hypoxia, and inflammation, including TNF-alpha, TGF-beta, and ferritin. All women were HIV-negative. RESULTS: Although malaria was associated with a reduction in maternal haemoglobin (10.8 g/dL vs. 12.1 g/dL, p < 0.001), no reduction in cord haemoglobin and no significant relationship between maternal and cord haemoglobin levels were found. Cord blood markers of haematological and hypoxic statuses did not differ between malaria-infected and uninfected women. Maternal malaria was associated with decreased TGF-beta and increased cord ferritin, the latter of which was positively correlated with parasitaemia (r = 0.474, p = 0.009). Increased cord ferritin was associated with significantly decreased birth weight and gestational length, although maternal and cord haemoglobin levels and malaria status had no effect on birth outcome. CONCLUSION: In this population, cord haemoglobin levels were protected from the effect of maternal malaria. However, decreased TGF-beta and elevated ferritin levels in cord blood suggest foetal immune activation to maternal malaria, which may help explain poor birth outcomes.

Placental malaria induces variant-specific antibodies of the cytophilic subtypes immunoglobulin G1 (IgG1) and IgG3 that correlate with adhesion inhibitory activity.

Antibodies targeting variant antigens on the surfaces of chondroitin sulfate A (CSA)-binding malaria-infected erythrocytes have been linked to protection against the complications of malaria in pregnancy. We examined the isotype/subtype profiles of antibodies that bound to variant surface antigens expressed by CSA-adherent Plasmodium falciparum in pregnant Malawian women with and without histologically defined placental malaria. Women in their first pregnancy with placental malaria produced significantly greater amounts of immunoglobulin G1 (IgG1) and IgG3 reactive with surface antigens of malaria-infected erythrocytes than uninfected women of the same gravidity. IgG1 and IgG3 levels in infected and control women in later pregnancies were similar to those in infected women in their first pregnancy. Levels of IgG2 and IgG4 were similarly low in infected and uninfected women of all gravidities. IgM that bound to the surface of CSA-adherent P. falciparum occurred in all groups of women and malaria-naïve controls. There was a significant correlation between IgG1 and IgG3 levels, indicating that women usually produced both subtypes. Levels of IgG1 and IgG3 correlated with the ability of serum or plasma to inhibit parasite adhesion to CSA. Taken together, these data suggest that IgG1 and IgG3 dominate the IgG response to placental-type variant surface antigens. They may function by blocking parasite adhesion to placental CSA, but given their cytophilic nature, they might also opsonize malaria-infected erythrocytes for interaction with Fc receptors on phagocytic cells.

Mutations associated with sulfadoxine-pyrimethamine and chlorproguanil resistance in Plasmodium falciparum isolates from Blantyre, Malawi.

We conducted a prevalence study of mutations in Plasmodium falciparum that are associated with antifolate resistance in Blantyre, Malawi. The dihydrofolate reductase 164-Leu mutation, which confers resistance to both pyrimethamine and chlorproguanil, was found in 4.7% of the samples. Previously unreported mutations in dihydropteroate synthase were also found.

Are public antenatal clinics in Blantyre, Malawi, ready to offer services for the prevention of vertical transmission of HIV?

At least 100% of the adult population in Malawi is infected with HIV and vertical transmission is a major mode of transmission. Currently, there are plans to provide widespread antiretroviral therapy to prevent mother to child transmission of HIV. This study was conducted to describe the perceptions of midwives towards selected issues regarding prevention of mother to child transmission of HIV in eleven public health centres in Blantyre, Malawi. A cross-sectional study using a self-administered questionnaire incorporating both open-ended and closed-ended questions was used. Twenty seven midwives participated in the study. Less than half (40.7%), of them reported working at a baby friendly hospital initiative health facility, while 96.3% reported that they would advise an HIV infected woman to breastfeed her infant. HIV prevention messages were reportedly offered routinely by 77.8% of the respondents, but only 22.2% reported that their clinics offered condoms to pregnant women. Also, only 37.0% reported offering routine STI screening, while 37.0% of the midwives would support antenatal women being accompanied by their male partners Majority (81.2%) said that women who know they are HIV infected should not become pregnant, while 37.0% reported that they would be uncomfortable to assist in the delivery of an HIV infected woman. There was lack of appropriate clinic space and sterile gloves for the proper delivery of maternity services. Midwives in Malawi need training, supervision and other support to provide adequate health care services to antenatal women.

Risk factors and mechanisms of preterm delivery in Malawi.

PROBLEM: We examined risk factors and mechanisms of preterm delivery (PTD) in malaria-exposed pregnant women in Blantyre, Malawi. METHOD OF STUDY: The human immunodeficiency virus (HIV), malaria, syphilis, and anemia were assessed in a cross-sectional study of 572 pregnant women. In a nested case-control study, chorioamnionitis (CAM) was examined; tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, macrophage inflammatory protein (MIP)-1alpha, monocyte chemotactic protein (MCP)-1, transforming growth factor (TGF)-beta, cortisol, and corticotropin-releasing hormone were measured in placental, maternal and/or cord blood. RESULTS: HIV, infrequent antenatal clinic attendance, low-maternal weight, no intermittent preventive malaria therapy (IPT), and CAM were associated with PTD, while malaria was not. Of the 18 compartmental cytokine measurements, elevations in placental and/or cord IL-6 and IL-8 were associated with both CAM and PTD. In contrast, there was no overlap between the cytokines affected by malaria and those associated with PTD. CONCLUSIONS: The HIV and CAM were the major infections associated with PTD in this study. CAM, but not malaria, causes PTD via its effect on proinflammatory cytokines.

Impairment of humoral immunity to Plasmodium falciparum malaria in pregnancy by HIV infection.

BACKGROUND: HIV infection increases the risk of malaria infection in pregnant women. Antibodies to variant surface antigens (VSA) on infected erythrocytes might protect against malaria in pregnancy. We postulated that HIV-induced impairment of humoral immunity to VSA mediates the increased susceptibility to malaria. METHODS: We compared serum concentrations of antibodies to VSA by flow cytometry or agglutination, and to merozoite proteins AMA-1 and MSP119 by ELISA, in 298 pregnant Malawian women, and related the findings to malaria and HIV infection, CD4-positive T-cell count, and HIV-1 viral load. FINDINGS: Concentrations of IgG to placental type VSA were lower in HIV-infected women than in HIV-uninfected women (median 8 units [IQR 4-23] vs 20 [12-30]; p<0.0001), among women with malaria (p=0.009) and those without malaria (p=0.0062). The impairment was greatest in first pregnancy. Agglutinating antibodies to placental VSA were present in a lower proportion of HIV-infected than HIV-uninfected women (58 [35.1%] of 165 vs 50 [53.8%] of 93, p<0.001). The degree of antibody binding by flow cytometry was correlated with CD4-positive T-cell count (r=0.16, p=0.019) and inversely with HIV-1 viral load (r=-0.16, p=0.030). Concentrations of antibodies to AMA-1 were lower in HIV infection (p<0.0001) but were not correlated with CD4-positive T-cell count or viral load. Responses to MSP119 were little affected by HIV infection. In multivariate analyses, HIV was negatively associated with amount of antibody to both VSA and AMA-1 (p<0.001 for each) but not MSP119. INTERPRETATION: HIV infection impairs antimalarial immunity, especially responses to placental type VSA. The impairment is greatest in the most immunosuppressed women and could explain the increased susceptibility to malaria seen in pregnant women with HIV infection.

The effect of Plasmodium falciparum malaria on peripheral and placental HIV-1 RNA concentrations in pregnant Malawian women.

OBJECTIVE: To investigate the effect of placental Plasmodium falciparum malaria infection on peripheral and/or placental HIV-1 viral load. DESIGN: A cross-sectional study of HIV-infected pregnant women, with and without placental malaria, delivering at Queen Elizabeth Central Hospital in Malawi. METHODS: Peripheral blood samples were collected from consenting women and tested for HIV. HIV-infected women received nevirapine at the onset of labor. At delivery, placental blood and tissue specimens were collected. HIV-1 RNA concentrations were measured in peripheral and placental plasma samples, and malaria infection was determined by placental histopathology. RESULTS: Of the 480 HIV-infected women enrolled, 304 had placental histopathology performed, of whom 74 (24.3%) had placental malaria. Compared with women without placental malaria, those with placental malaria had a 2.5-fold higher geometric mean peripheral HIV-1 RNA concentration (62,359 versus 24 814 copies/ml; P = 0.0007) and a 2.4-fold higher geometric mean placental HIV-1 RNA concentration (11,733 versus 4919 copies/ml; P = 0.008). In multivariate analyses, after adjusting for CD4 cell count and other covariates, placental malaria was associated with a 1.7-fold increase in geometric mean peripheral HIV-1 RNA concentration (47,747 versus 27,317 copies/ml; P = 0.02) and a 2.0-fold increase in geometric mean placental HIV-1 RNA concentration (9670 versus 4874 copies/ml; P = 0.03). CONCLUSION: Placental malaria infection is associated with an increase in peripheral and placental HIV-1 viral load, which might increase the risk of mother-to-child transmission of HIV.

Antibodies to variant surface antigens of Plasmodium falciparum-infected erythrocytes and adhesion inhibitory antibodies are associated with placental malaria and have overlapping and distinct targets.

We measured antibodies to chondroitin sulfate A (CSA)-binding and placental Plasmodium falciparum-infected red blood cells (PRBCs) among pregnant women with or without placental malaria. Immunoglobulin G to PRBC surface antigens was rare in uninfected primigravidae (3.7%), more prevalent in infected primigravidae (70%; P<.001), and common in infected (77%) and uninfected (83%) multigravidae. Similar patterns were seen for agglutinating antibodies, and antibodies were similar among women with past or active placental infection. PRBC adhesion to CSA was inhibited 60% by serum from infected primigravidae but 24% by serum from uninfected primigravidae (P=.025), whereas infection did not alter adhesion inhibition by multigravidae (77% inhibition)[corrected]. There was substantial heterogeneity in antibody type and levels. Antibodies did not correlate with parasite density or pregnancy outcome. Comparisons between antibodies suggest that adhesion-inhibitory antibodies and those to PRBC variant antigens have distinct and overlapping epitopes, may be acquired independently, and have different roles in immunity.

Likely stakeholders in the prevention of mother to child transmission of HIV/AIDS in Blantyre, Malawi.

OBJECTIVES: To determine potential partners for pregnant women in the prevention of mother to child transmission of HIV and to determine pregnant women's perceptions towards selected potential HIV prevention efforts. DESIGN: Cross sectional, questionnaire-administered study. SETTING: Ante-natal clinics of eleven public health centers and the major referral and university teaching hospital of Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi. SUBJECTS: A total of 321 pregnant women attending ante-natal clinics. RESULTS: Antenatal women in Blantyre, Malawi obtain health information on HIV/AIDS from the radio (96.3%), health workers (82.2%), religious gatherings (66.7%), friends (54.8%) and newspapers (39.3%). The majority intend to be accompanied by own mother and sister for delivery (52.4% and 15.4% respectively). Almost all (99%) planned to breast feed with 91.8% reporting an intended breastfeeding period of at least 6 months. About 97% of married women reported desire to tell spouse in case of HIV sero-positive results while only 65.1% had ever discussed about HIV with spouse, and only 5.2% had ever attended antenatal clinic with spouse. Whether woman had ever discussed about HIV/AIDS with spouse or not did not influence desire to disclose HIV status to spouse. CONCLUSION: Close relatives, spouse and the media are important stakeholders in the health of pregnant women. Programs aimed at prevention of mother to child transmission of HIV should give serious consideration to these partners.

Host response to malaria during pregnancy: placental monocyte recruitment is associated with elevated beta chemokine expression.

Malaria during pregnancy is associated with poor birth outcomes, particularly low birth weight. Recently, monocyte infiltration into the placental intervillous space has been identified as a key risk factor for low birth weight. However, the malaria-induced chemokines involved in recruiting and activating placental monocytes have not been identified. In this study, we determined which chemokines are elevated during placental malaria infection and the association between chemokine expression and placental monocyte infiltration. Placental malaria infection was associated with elevations in mRNA expression of three beta chemokines, macrophage-inflammatory protein 1 (MIP-1) alpha (CCL3), monocyte chemoattractant protein 1 (MCP-1; CCL2), and I-309 (CCL1), and one alpha chemokine, IL-8 (CXCL8); all correlated with monocyte density in the placental intervillous space. Placental plasma concentrations of MIP-1 alpha and IL-8 were increased in women with placental malaria and were associated with placental monocyte infiltration. By immunohistochemistry, we localized placental chemokine production in malaria-infected placentas: some but not all hemozoin-laden maternal macrophages produced MIP-1 beta and MCP-1, and fetal stromal cells produced MCP-1. In sum, local placental production of chemokines is increased in malaria, and may be an important trigger for monocyte accumulation in the placenta.

Placental monocyte infiltrates in response to Plasmodium falciparum malaria infection and their association with adverse pregnancy outcomes.

Maternal anemia and low birth weight (LBW) may complicate malaria in pregnancy, and placental monocyte infiltrates have been associated with LBW, and anecdotally with anemia. We examined placental pathology from 357 Malawian women. Intervillous monocyte infiltrates were frequent in placental malaria and were not seen in uninfected placentas. Histology was grouped according to a 5-point scale. Dense monocyte infiltrates and presence of intramonocytic malaria pigment were associated with anemia and LBW. Of factors associated with LBW and/or anemia in univariate analysis, gravidity (P = 0.002), number of antenatal clinic (ANC) visits (P < 0.001), malaria pigment in fibrin (P = 0.03), and monocyte malaria pigment (P = 0.0001) remained associated with lower birth weight by multivariate analysis. Associated with maternal anemia were HIV infection (P < 0.0001), intervillous monocyte numbers (P < 0.0001), number of ANC visits (P = 0.002), and recent febrile symptoms (P = 0.0001). Pigment-containing placental monocytes are associated with anemia and LBW due to malaria, and may have a causative role in their development.

Placental tumor necrosis factor alpha but not gamma interferon is associated with placental malaria and low birth weight in Malawian women.

Malaria in pregnancy predisposes to maternal anemia and low birth weight (LBW). We examined the possible roles of the cytokines tumor necrosis factor alpha (TNF-alpha) and gamma interferon (IFN-gamma) in these adverse outcomes. We measured cytokine concentrations in placental, peripheral, and cord blood plasma in relation to malaria parasitemia and placental monocyte accumulation in 276 Malawian women. Maternal hemoglobin concentration, human immunodeficiency virus status, and infant birth weight were determined. Concentrations of TNF-alpha in placental blood were correlated with densities of Plasmodium falciparum-infected erythrocytes (P < 0.0001) and of intervillous monocyte infiltrates (P < 0.0001) on placental histology. Peripheral blood TNF-alpha concentrations were relatively low and were weakly associated with malaria. TNF-alpha concentrations were higher in placental blood, where they were strongly associated with malaria. Placental plasma TNF-alpha levels were higher in women who had LBW babies (P = 0.0027), women with febrile symptoms (P < 0.0001), and teenage mothers (P = 0.04) than in other women. The presence of TNF-alpha in cord blood was not associated with malaria infection. IFN-gamma levels were infrequently elevated, and elevated IFN-gamma levels were not associated with poor pregnancy outcomes. Placental production of TNF-alpha, but not of IFN-gamma, may be implicated in impaired fetal growth in Malawian women.

Perinatal mortality audit at Tikure Anbessa Teaching Hospital, Addis Ababa, Ethiopia: 1995 to 1996.

OBJECTIVES: To determine the prevalence and causes of perinatal mortality rates at Tikure Anbessa hospital, Ethiopia, 1995-96. DESIGN: A cross-sectional review of hospital records of all women who delivered at Tikure Anbessa Hospital. Data were collected prospectively. SETTING: Teaching Hospital of Tikure Anbessa, Addis Ababa, Ethiopia. SUBJECTS: Women and neonates from 8986 deliveries. Deliveries exceeding 28 weeks of gestation or birth weight of 1000 grams were considered. MATERIALS AND METHODS: All deliveries were included for infants whose gestational age exceeded 28 completed weeks. When the gestational age was unknown, the birth weight of 1000 grams or more was considered. All perinatal deaths and obstetric complications were identified. Labour chart, mode of delivery and summary of delivery had been recorded by the responsible resident at a monthly combined obstetric and paediatric perinatal mortality meeting. Age of the mother, parity, booking status for antenatal care, obstetric complications, labour, mode of delivery, birth weight, gestational age, one and five minutes Apgar scores were collected. RESULTS: A total of 8986 deliveries were conducted during the study period. Of these 6933 (77.2%) were booked for antenatal care while the remaining 2053 (22.8%) were not booked in any health institution. The perinatal mortality rate of the hospital was 71.6 per 1000 live births. The risk of perinatal mortality was more than doubled among mothers who failed to book for antenatal care follow-up and no laboratory investigations was done were birth asphyxia followed by premature birth 15.4% and 12% respectively. CONCLUSIONS: Perinatal mortality rates are high at Tikure Anbessa Hospital, Ethiopia. There is need to ensure that pregnant women are booked for antenatal care so as to provide adequate antenatal and perinatal health care.