45 research outputs found

    Induction of HO-1 in tissue macrophages and monocytes in fatal falciparum malaria and sepsis

    Get PDF
    BACKGROUND: As well as being inducible by haem, haemoxygenase -1 (HO-1) is also induced by interleukin-10 and an anti-inflammatory prostaglandin, 15d PGJ(2), the carbon monoxide thus produced mediating the anti-inflammatory effects of these molecules. The cellular distribution of HO-1, by immunohistochemistry, in brain, lung and liver in fatal falciparum malaria, and in sepsis, is reported. METHODS: Wax sections were stained, at a 1:1000 dilution of primary antibody, for HO-1 in tissues collected during paediatric autopsies in Blantyre, Malawi. These comprised 37 acutely ill comatose patients, 32 of whom were diagnosed clinically as cerebral malaria and the other 5 as bacterial diseases with coma. Another 3 died unexpectedly from an alert state. Other control tissues were from Australian adults. RESULTS: Apart from its presence in splenic red pulp macrophages and microhaemorrhages, staining for HO-1 was confined to intravascular monocytes and certain tissue macrophages. Of the 32 clinically diagnosed cerebral malaria cases, 11 (category A) cases had negligible histological change in the brain and absence of or scanty intravascular sequestration of parasitized erythrocytes. Of these 11 cases, eight proved at autopsy to have other pathological changes as well, and none of these eight showed HO-1 staining within the brain apart from isolated moderate staining in one case. Two of the three without another pathological diagnosis showed moderate staining of scattered monocytes in brain vessels. Six of these 11 (category A) cases exhibited strong lung staining, and the Kupffer cells of nine of them were intensely stained. Of the seven (category B) cases with no histological changes in the brain, but appreciable sequestered parasitised erythrocytes present, one was without staining, and the other six showed strongly staining, rare or scattered monocytes in cerebral vessels. All six lung sections not obscured by neutrophils showed strong staining of monocytes and alveolar macrophages, and all six available liver sections showed moderate or strong staining of Kupffer cells. Of the 14 (category C) cases, in which brains showed micro-haemorrhages and intravascular mononuclear cell accumulations, plus sequestered parasitised erythrocytes, all exhibited strong monocyte HO-1 staining in cells forming accumulations and scattered singly within cerebral blood vessels. Eleven of the available and readable 13 lung sections showed strongly staining monocytes and alveolar macrophages, and one stained moderately. All of the 14 livers had strongly stained Kupffer cells. Of five cases of comatose culture-defined bacterial infection, three showed a scattering of stained monocytes in vessels within the brain parenchyma, three had stained cells in lung sections, and all five demonstrated moderately or strongly staining Kupffer cells. Brain sections from all three African controls, lung sections from two of them, and liver from one, showed no staining for HO-1, and other control lung and liver sections showed few, palely stained cells only. Australian-origin adult brains exhibited no staining, whether the patients had died from coronary artery disease or from non-infectious, non-cerebral conditions CONCLUSIONS: Clinically diagnosed 'cerebral malaria' in children includes some cases in whom malaria is not the only diagnosis with the hindsight afforded by autopsy. In these patients there is widespread systemic inflammation, judged by HO-1 induction, at the time of death, but minimal intracerebral inflammation. In other cases with no pathological diagnosis except malaria, there is evidence of widespread inflammatory responses both in the brain and in other major organs. The relative contributions of intracerebral and systemic host inflammatory responses in the pathogenesis of coma and death in malaria deserve further investigation

    ABO blood group phenotypes influence parity specific immunity to Plasmodium falciparum malaria in Malawian women

    Get PDF
    Background: Blood group O has been significantly associated with increased placental malaria infection in primiparae and reduced risk of infection in multiparae in the Gambia, an area with markedly seasonal malaria transmission. This study analyses the association between ABO blood group phenotypes in relation to placental malaria pathology and birth outcomes in southern Malawi, an area with perennial malaria transmission. Methods: A cross- sectional study of 647 mother/ child pairs delivering in Montfort Hospital, Chikwawa District between February- June 2004 and January- July 2005 was undertaken. Maternal peripheral and cord blood samples were obtained at delivery. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection. Birth anthropometry was recorded. ABO blood group was measured by agglutination. Results: In primiparae, blood group O was significantly associated with increased risk of active placental infection ( OR 2.18, 95% CI 1.15 - 4.6, p = 0.02) and an increased foetal- placental weight ratio compared to non- O phenotypes ( 5.68 versus 5.45, p = 0.03) In multiparae blood group O was significantly associated with less frequent active placental infection ( OR 0.59, 95% CI 0.36 - 0.98, p = 0.04), and a higher newborn ponderal index compared to non- O phenotypes ( 2.65 versus 2.55, p = 0.007). In multivariate regression parity was independently associated with increased risk of placental malaria ( active andpast infection) in primiparae with blood group O ( p = 0.034) and reduced risk in multiparae with the same phenotype ( p = 0.015). Conclusion: Parity related susceptibility to placental malaria is associated with the mothers ABO phenotype. This interaction influences foetal and placental growth and could be an important modifying factor for pregnancy outcomes. The biological explanation could relate to sialic acid dependent placental membrane differences which vary with ABO blood group

    High rates of cervical cancer among HIV-infected women at a referral hospital in Malawi

    Get PDF
    Cervical cancer is the most common cancer among women in Malawi. National guidelines recommend screening women aged 30–45 years every five years; however, no specific recommendations exist for women with HIV. We aimed to assess the frequency of high-grade dysplasia (CIN 2 or CIN3) and cervical cancer among women in central Malawi and to examine associations with CIN2+ (CIN2/3 or cancer)

    Tissue distribution of migration inhibitory factor and inducible nitric oxide synthase in falciparum malaria and sepsis in African children

    Get PDF
    BACKGROUND: The inflammatory nature of falciparum malaria has been acknowledged since increased circulating levels of tumour necrosis factor (TNF) were first measured, but precisely where the mediators downstream from this prototype inflammatory mediator are generated has not been investigated. Here we report on the cellular distribution, by immunohistochemistry, of migration inhibitory factor (MIF) and inducible nitric oxide synthase (iNOS) in this disease, and in sepsis. METHODS: We stained for MIF and iNOS in tissues collected during 44 paediatric autopsies in Blantyre, Malawi. These comprised 42 acutely ill comatose patients, 32 of whom were diagnosed clinically as cerebral malaria and the other 10 as non-malarial diseases. Another 2 were non-malarial, non-comatose deaths. Other control tissues were from Australian adults. RESULTS: Of the 32 clinically diagnosed cerebral malaria cases, 11 had negligible histological change in the brain, and no or scanty intravascular sequestration of parasitised erythrocytes, another 7 had no histological changes in the brain, but sequestered parasitised erythrocytes were present (usually dense), and the remaining 14 brains showed micro-haemorrhages and intravascular mononuclear cell accumulations, plus sequestered parasitised erythrocytes. The vascular walls of the latter group stained most strongly for iNOS. Vascular wall iNOS staining was usually of low intensity in the second group (7 brains) and was virtually absent from the cerebral vascular walls of 8 of the 10 comatose patients without malaria, and also from control brains. The chest wall was chosen as a typical non-cerebral site encompassing a range of tissues of interest. Here pronounced iNOS staining in vascular wall and skeletal muscle was present in some 50% of the children in all groups, including septic meningitis, irrespective of the degree of staining in cerebral vascular walls. Parasites or malarial pigment were rare to absent in all chest wall sections. While MIF was common in chest wall vessels, usually in association with iNOS, it was absent in brain vessels. CONCLUSIONS: These results agree with the view that clinically diagnosed cerebral malaria in African children is a collection of overlapping syndromes acting through different organ systems, with several mechanisms, not necessarily associated with cerebral vascular inflammation and damage, combining to cause death

    Human papillomavirus in head and neck squamous cell carcinoma: A descriptive study of histologically confirmed cases at Kamuzu Central Hospital in Lilongwe, Malawi

    Get PDF
    Background: Head and neck squamous cell carcinoma (HNSCC) is common in sub-Saharan Africa, but the aetiologic contribution of human papillomavirus (HPV) is not well established.Methods: We assessed HNSCC cases for HPV using p16 immunohistochemistry (IHC) in Malawi. Associations between p16 IHC and tumour site, behavioural risk factors, demographic characteristics, and HIV status were examined.Results: From 2010 to 2014, 77 HNSCC cases were identified. Mean age was 52 years, 50 cases (65%) were male, and 48 (62%) were in the oropharynx (OP) or oral cavity (OC). HIV status was known for 35 patients (45%), with 5 (14%) HIV-infected. Substance use was known for 40 patients (52%), with 38% reporting any tobacco and 31% any alcohol. Forty-two cases (55%) had adequate tissue for p16 IHC, of which seven (17%) were positive, including 22% of OP/OC tumours.Conclusions: Despite high cervical cancer burden, HPV-associated HNSCC is not very common in Malaw

    Clinical breast examination screening by trained laywomen in Malawi integrated with other health services

    Get PDF
    Breast cancer awareness and early detection are limited in sub-Saharan Africa. Resource limitations make screening mammography or clinical breast exam (CBE) by physicians or nurses impractical in many settings. We aimed to assess feasibility and performance of CBE by laywomen in urban health clinics in Malawi

    CHOP Chemotherapy for Aggressive Non-Hodgkin Lymphoma with and without HIV in the Antiretroviral Therapy Era in Malawi

    Get PDF
    There are no prospective studies of aggressive non-Hodgkin lymphoma (NHL) treated with CHOP in sub-Saharan Africa. We enrolled adults with aggressive NHL in Malawi between June 2013 and May 2015. Chemotherapy and supportive care were standardized, and HIV+ patients received antiretroviral therapy (ART). Thirty-seven of 58 patients (64%) were HIV+. Median age was 47 years (IQR 39–56), and 35 (60%) were male. Thirty-five patients (60%) had stage III/IV, 43 (74%) B symptoms, and 28 (48%) performance status ≥2. B-cell NHL predominated among HIV+ patients, and all T-cell NHL occurred among HIV- individuals. Thirty-one HIV+ patients (84%) were on ART for a median 9.9 months (IQR 1.1–31.7) before NHL diagnosis, median CD4 was 121 cells/μL (IQR 61–244), and 43% had suppressed HIV RNA. HIV+ patients received a similar number of CHOP cycles compared to HIV- patients, but more frequently developed grade 3/4 neutropenia (84% vs 31%, p = 0.001), resulting in modestly lower cyclophosphamide and doxorubicin doses with longer intervals between cycles. Twelve-month overall survival (OS) was 45% (95% CI 31–57%). T-cell NHL (HR 3.90, p = 0.017), hemoglobin (HR 0.82 per g/dL, p = 0.017), albumin (HR 0.57 per g/dL, p = 0.019), and IPI (HR 2.02 per unit, p<0.001) were associated with mortality. HIV was not associated with mortality, and findings were similar among patients with diffuse large B-cell lymphoma. Twenty-three deaths were from NHL (12 HIV+, 11 HIV-), and 12 from CHOP (9 HIV+, 3 HIV-). CHOP can be safe, effective, and feasible for aggressive NHL in Malawi with and without HIV

    Early Experience after Developing a Pathology Laboratory in Malawi, with Emphasis on Cancer Diagnoses

    Get PDF
    Abstract Background: Despite increasing cancer burden in Malawi, pathology services are limited. We describe operations during the first 20 months of a new pathology laboratory in Lilongwe, with emphasis on cancer diagnoses

    Early Experience after Developing a Pathology Laboratory in Malawi, with Emphasis on Cancer Diagnoses

    Get PDF
    BackgroundDespite increasing cancer burden in Malawi, pathology services are limited. We describe operations during the first 20 months of a new pathology laboratory in Lilongwe, with emphasis on cancer diagnoses.Methods and FindingsWe performed a cross-sectional study of specimens from the Kamuzu Central Hospital pathology laboratory between July 1, 2011 and February 28, 2013. Patient and specimen characteristics, and final diagnoses are summarized. Diagnoses were categorized as malignant, premalignant, infectious, other pathology, normal or benign, or nondiagnostic. Patient characteristics associated with premalignancy and malignancy were assessed using logistic regression. Of 2772 specimens, 2758 (99%) with a recorded final diagnosis were included, drawn from 2639 unique patients. Mean age was 38 years and 63% were female. Of those with documented HIV status, 51% had unknown status, and 36% with known status were infected. Histologic specimens comprised 91% of cases, and cytologic specimens 9%. Malignant diagnoses were most common overall (n = 861, 31%). Among cancers, cervical cancer was most common (n = 117, 14%), followed by lymphoma (n = 91, 11%), esophageal cancer (n = 86, 10%), sarcoma excluding Kaposi sarcoma (n = 75, 9%), and breast cancer (n = 61, 7%). HIV status was known for 95 (11%) of malignancies, with HIV prevalence ranging from 9% for breast cancer to 81% for cervical cancer. Increasing age was consistently associated with malignancy [bivariable odds ratio 1.24 per decade increase (95% CI 1.19–1.29) among 2685 patients with known age; multivariable odds ratio 1.33 per decade increase (95% CI 1.14–1.56) among 317 patients with known age, gender, and HIV status], while HIV infection and gender were not.ConclusionsDespite selection and referral bias inherent in these data, a new pathology laboratory in Lilongwe has created a robust platform for cancer care and research. Strategies to effectively capture clinical information for pathologically confirmed cancers can allow these data to complement population-based registration

    Assessment of mixed plasmodium falciparum sera5 infection in endemic burkitt lymphoma : A case-control study in Malawi

    Get PDF
    Background: Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in Africa and is linked to Plasmodium falciparum (Pf) malaria infection, one of the most common and deadly childhood infections in Africa; however, the role of Pf genetic diversity is unclear. A potential role of Pf genetic diversity in eBL has been suggested by a correlation of age-specific patterns of eBL with the complexity of Pf infection in Ghana, Uganda, and Tanzania, as well as a finding of significantly higher Pf genetic diversity, based on a sensitive molecular barcode assay, in eBL cases than matched controls in Malawi. We examined this hypothesis by measuring diversity in Pf-serine repeat antigen-5 (Pfsera5), an antigenic target of blood-stage immunity to malaria, among 200 eBL cases and 140 controls, all Pf polymerase chain reaction (PCR)-positive, in Malawi. Methods: We performed Pfsera5 PCR and sequencing (~3.3 kb over exons II–IV) to determine single or mixed PfSERA5 infection status. The patterns of Pfsera5 PCR positivity, mixed infection, sequence variants, and haplotypes among eBL cases, controls, and combined/pooled were analyzed using frequency tables. The association of mixed Pfsera5 infection with eBL was evaluated using logistic regression, controlling for age, sex, and previously measured Pf genetic diversity. Results: Pfsera5 PCR was positive in 108 eBL cases and 70 controls. Mixed PfSERA5 infection was detected in 41.7% of eBL cases versus 24.3% of controls; the odds ratio (OR) was 2.18, and the 95% confidence interval (CI) was 1.12–4.26, which remained significant in adjusted results (adjusted odds ratio [aOR] of 2.40, 95% CI of 1.11–5.17). A total of 29 nucleotide variations and 96 haplotypes were identified, but these were unrelated to eBL. Conclusions: Our results increase the evidence supporting the hypothesis that infection with mixed Pf infection is increased with eBL and suggest that measuring Pf genetic diversity may provide new insights into the role of Pf infection in eBL
    corecore