Discordance between PAM50 intrinsic subtyping and immunohistochemistry in South African women with breast cancer.

PURPOSE: Breast cancer is a heterogeneous disease with different gene expression profiles, treatment options and outcomes. In South Africa, tumors are classified using immunohistochemistry. In high-income countries multiparameter genomic assays are being utilized with implications for tumor classification and treatment. METHODS: In a cohort of 378 breast cancer patients from the SABCHO study, we investigated the concordance between tumor samples classified by IHC and the PAM50 gene assay. RESULTS: IHC classified patients as ER-positive (77.5%), PR-positive (70.6%), and HER2-positive (32.3%). These results, together with Ki67, were used as surrogates for intrinsic subtyping, and showed 6.9% IHC-A-clinical, 72.7% IHC-B-clinical, 5.3% IHC-HER2-clinical and 15.1% triple negative cancer (TNC). Typing using the PAM50 gave 19.3% luminal-A, 32.5% luminal-B, 23.5% HER2-enriched and 24.6% basal-like. The basal-like and TNC had the highest concordance, while the luminal-A and IHC-A group had the lowest concordance. By altering the cutoff for Ki67, and realigning the HER2/ER/PR-positive patients to IHC-HER2, we improved concordance with the intrinsic subtypes. CONCLUSION: We suggest that the Ki67 be changed to a cutoff of 20-25% in our population to better reflect the luminal subtype classifications. This change would inform treatment options for breast cancer patients in settings where genomic assays are unaffordable.

PAM50 intrinsic subtypes, risk of recurrence score and breast cancer survival in HIV-positive and HIV-negative patients-a South African cohort study.

PURPOSE: Treatment decision making for patients with breast cancer increasingly depends on analysis of markers or systems for estimating risk of breast cancer recurrence. Breast cancer intrinsic subtypes and risk of recurrence (ROR) scores have been found to be valuable in predicting survival and determining optimal treatment for individual patients. We studied the association of breast cancer survival with the PAM50 gene expression assay in HIV-positive and HIV-negative patients. METHOD: RNA was extracted from formalin-fixed paraffin-embedded specimens of histologically confirmed invasive carcinoma and was purified using the AllPrep® DNA/RNA FFPE kit, Qiagen (Hilden, Germany). The NanoString RUO PAM50 algorithm was used to determine the molecular subtype and the risk of recurrence score of each sample. The overall and disease-free survival were determined with comparison made among HIV-positive and -negative patients. We then generated Kaplan-Meier survival curves, calculated p-values and estimated hazard ratios and their 95% confidence intervals using Cox regression models. RESULTS: Of the 384 RNA samples analysed, 98.4% met the required RNA quality standard and the specified QC threshold for the test. Luminal B was the most common PAM50 intrinsic subtype and 82.1% of patients were at high risk for disease recurrence based on ROR score. HIV infection, PAM50-based HER2-enriched and basal-like intrinsic subtypes, and high ROR were associated with poor overall and disease-free survival. HIV-positive patients with luminal A & B subtypes had significantly worse survival outcomes than HIV-negative luminal patents. CONCLUSION: Aggressive tumour biology was common in our cohort. HIV infection, PAM50 HER2-enriched,basal-like intrinsic subtypes and high ROR score were associated with poor overall and disease-free survival. HIV infection impacted survival in patients with luminal subtypes only.

Interleukin-6 gene polymorhisms and interleukin-6 levels are associated with atherosclerosis in CKD patients.

Inflammation is a major risk factor for atherosclerosis. Genetic polymorphisms in the inflammatory cytokine genes have been associated with atherosclerosis. Because levels of inflammatory cytokines are markedly elevated in patients with chronic kidney disease (CKD), we hypothesized that genotypic variations in the interleukin-6 (IL-6) gene are a cause of systemic inflammatory states and atherosclerosis in South African CKD patients. 120 CKD patients and 40 healthy controls were included. Serum IL-6 and high-sensitivity C-reactive protein (hs-CRP) levels were measured. Functional polymorphisms in the IL-6 genes were genotyped using polymerase chain reaction-sequence specific primer (PCR-SSP) methods. Carotid intima-media thickness (CIMT) and the presence of plaque were assessed by B-mode ultrasonography. Serum IL-6 and hs-CRP levels were increased in patients with CKD compared with healthy controls (p < 0.001). In CKD patients, serum IL-6 above the median value was associated with carotid plaque (OR: 2.11; 95% CI: 1.74 - 2.57, p = 0.004), with excess risk confined to the group with high IL-6 levels. Significant associations were found between the IL-6 gene and atherosclerosis in the CKD group (for G/G genotype: OR = 1.21, 95% CI = 1.05 - 1.39, p = 0.012; for GG+GC vs. CC: OR = 1.14, 95% CI = 1.02 - 1.28, p = 0.035). Patients with GG+GC genotype of the IL-6 gene polymorphism had higher levels of IL-6 than those with CC genotype (p = 0.029). In South African CKD patients, the IL-6 gene promoter polymorphism is associated with high serum IL-6 levels and atherosclerosis. The relationship between atherosclerosis and -174G/C polymorphism in the IL-6 gene suggests that IL-6 may be a potential pro-inflammatory mediator of atherosclerosis in CKD patients.

Hepcidin and GDF-15 are potential biomarkers of iron deficiency anaemia in chronic kidney disease patients in South Africa.

BACKGROUND: Anaemia is a common presenting feature among patients with chronic kidney disease (CKD) and it is associated with poor clinical outcomes and quality of life. It is not clear if growth differentiation factor-15 (GDF-15) or hepcidin are useful as early markers of iron deficiency anaemia (IDA) among non-dialysis CKD patients. We therefore evaluated the diagnostic validity of GDF-15 and hepcidin as biomarkers of IDA among non-dialysis CKD patients in Johannesburg, South Africa. METHOD: An analytic cross-sectional study was conducted among non-dialysis CKD patients (n = 312) and apparently healthy controls (n = 184) from June to December 2016 at an Academic Hospital, in Johannesburg, South Africa. An interviewer administered proforma was used to obtain the socio-biological and clinical characteristics of the participants. Serum levels of GDF-15 and hepcidin were determined. Predictive logistic regression models were built and post estimation receiver operator characteristics were determined to evaluate diagnostic validity of hepcidin and GDF-15 for absolute and functional iron deficiency anaemia. RESULTS: About half (50.6%) of the participants were female while the participants' mean age was 49.7 ± 15.8 years. The predictive value of diagnosing absolute IDA among CKD patients using GDF-15 was 74.02% (95% CI: 67.62-80.42%) while the predictive value of diagnosing functional IDA among CKD patients using hepcidin was 70.1% (95% CI: 62.79-77.49%).There was a weak negative correlation between hepcidin levels and GFR (r = - 0.19, p = 0.04) in anaemic CKD patients, and between serum GDF-15 and haemoglobin (r = - 0.34, p = 0.001). Serum ferritin (ß = 0.00389, P-value< 0.001), was a predictor of log hepcidin. MCHC (ß = - 0.0220, P-value 0.005) and CKD stage (ß = 0.4761, P-value < 0.001), race (ß = 0.3429, P-value = 0.018) were predictors of log GDF-15. Both GDF-15 (adj OR: 1.0003, 95%CI: 1.0001-1.0005, P = 0.017) and hepcidin (adj OR: 1.003, 95%CI: 1.0004-1.0055, P = 0.023) were associated with iron deficiency anaemia after multiple linear regression modelling. CONCLUSION: Serum GDF-15 is a potential biomarker of absolute IDA, while hepcidin levels can predict functional IDA among CKD patients.

Low prevalence of apolipoprotein L1 gene variants in Black South Africans with hypertension-attributed chronic kidney disease
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Variants in apolipoprotein L1 (APOL1) gene were shown to be associated with higher rates of nondiabetic kidney disease in black patients compared with white patients. Frequencies of these variants differ substantially in African populations, suggesting that their contribution to kidney disease might differ. We determined the frequency and association of (APOL1) risk alleles with markers of kidney disease in black South Africans with hypertension-attributed chronic kidney disease (CKD) and their first-degree relatives. Black patients with hypertension-attributed CKD with an estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73m2 were included, together with their first-degree relatives. G1 (rs60910145 and rs73885319) and G2: rs71785313 single nucleotide polymorphisms were genotyped by restriction fragment length polymorphism. Similar to previous association studies, we mainly tested recessive genetic models. The allele frequencies of both the G1 and G2 (APOL1) risk alleles were similar amongst all the groups. There was no difference in the two-risk-allele frequency in CKD patients (10%) compared to controls (8.6%), p = 0.790. Carriage of two (APOL1) risk alleles (vs. zero or one risk allele) was not a predictor of hypertension-attributed CKD (OR, 0.85; 95% CI, 0.25 - 2.83; p = 0.790). Patients with CKD and first-degree relatives with and without (APOL1) risk alleles had statistically indistinguishable blood pressures, creatinine and HDL-cholesterol levels. Apolipoprotein L1 risk variants are present in black South Africans with similar frequencies between CKD patients, first-degree relatives, and healthy controls. The lack of association of these variants with hypertension-attributed CKD in this population needs to be explored further in studies with larger sample sizes.
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Influence of vitamin D receptor polymorphisms on biochemical markers of mineral bone disorders in South African patients with chronic kidney disease.

BACKGROUND: It remains unclear whether genetic factors may explain the reported variation in the levels of biochemical markers of chronic kidney disease mineral and bone disorders (CKD- MBD) across ethnic groups. Therefore, the aim of this study was to examine the influence of vitamin D receptor (VDR) polymorphisms on secondary hyperparathyroidism and its association with vitamin D levels in black and white South African study participants. METHODS: This was a cross sectional study involving 272 CKD stage 3- 5D patients and 90 healthy controls. The four major VDR polymorphisms (Bsm 1, Fok 1, Taq 1, and Apa1) were genotyped using the polymerase chain reaction- restriction fragment length polymorphism (PCR -RFLP) method. In addition, biochemical markers of CKD-MBD were measured to determine their associations with the four VDR polymorphisms. RESULTS: With the exception of Taq I polymorphism, the distribution of the VDR polymorphisms differed significantly between blacks and whites. In hemodialysis patients, the Bb genotype was significantly associated with moderate secondary hyperparathyroidism (OR, 3.88; 95 CI 1.13-13.25, p = 0.03) and severe hyperparathyroidism (OR, 2.54; 95 CI 1.08-5.96, p = 0.03). This was consistent with the observed higher levels of median parathyroid hormone, fibroblast growth factor 23 and mean phosphate in patients with Bb genotype. This candidate risk genotype (Bb) was over represented in blacks compared to whites (71.0% versus 55.6%, p < 0.0001). In an unadjusted regression model, FokFf genotype was found to be significantly associated with the risk of developing severe vitamin D deficiency < 15 ng/ml (OR, 1.89; 95 CI 1.17-3.07, p = 0.01). CONCLUSION: The VDR Bb genotype is an independent predictor of developing secondary hyperparathyroidism in patients with end stage kidney disease. In addition, study participants with FokFf genotype are at increased of developing severe 25 -hydroxyvitamin D [25(OH)D] deficiency.

Cementogenesis and osteogenesis in periodontal tissue regeneration by recombinant human transforming growth factor-ß3 : a pilot study in Papio ursinus.

OBJECTIVES: The aim of this study was to investigate cementogenesis and alveolar bone induction during in vivo periodontal tissue regeneration upon implantation of hTGF-ß3 in furcation defects of Papio ursinus and to evaluate the feasibility of gene expression studies. MATERIALS AND METHODS: Class II furcation defects (day 0) were prepared in mandibular first and second molars of three P. ursinus and on day 30 implanted with and without 75 µg hTGF-ß3 in Matrigel® matrix. On day 0, 30 and 90, cementum and alveolar bone were harvested for gene expression analyses. Coral-derived bioreactors with and without 250 µg hTGF-ß3 were implanted in the rectus abdominis to monitor tissue induction. RESULTS: hTGF-ß3 induced cementogenesis with TGF-ß3 , Cementum Protein-1 (Cemp1) and Osteocalcin (OC) up-regulation, and down-regulation of BMP-2 and OP-1. Matrigel® matrix specimens showed up-regulation of BMP-2, TGF-ß3 , and OC, with down-regulation of OP-1 and Cemp1. hTGF-ß3 induced alveolar bone with down-regulation of OP-1, TGF-ß3 , OC, and Cemp1. hTGF-ß3 bioreactors induced bone at the periphery only. BMP-3, BMP-4, TGF-ß1 and TGF-ß3 were up-regulated in the adjacent muscle with TGF-ß2 down-regulation. CONCLUSIONS: Cementogenesis and osteogenesis by hTGF-ß3 entail the expression and up-regulation of TGF-ß3 and OC with fine tuning and modulation of BMP-2 and OP-1.

Volume overload and its risk factors in South African chronic kidney disease patients: an appraisal of bioimpedance spectroscopy and inferior vena cava measurements.

BACKGROUND: Fluid retention occurs early in chronic kidney disease (CKD) resulting in increased cardiovascular morbidity and mortality. This study aimed to assess volume and nutritional status among South African CKD participants and determine the relationship between malnutrition, inflammation, atherosclerosis, and volume overload using a body composition monitor (BCM). We also evaluated the usefulness of BCM measurement in assessing volume overload. METHODS: 160 participants comprising hemodialysis, peritoneal dialysis, stage 3 CKD patients, and healthy controls (40 in each group) were studied. A BCM was used to assess fluid and nutritional status. Cardiac dimension measurements, and inferior vena cava diameter (IVCD) and carotid intima media thickness were assessed by echocardiography and ultrasonography, respectively. Serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels were measured as markers of inflammation. RESULTS: Fluid overload and malnutrition were present in 68% and 63% of studied patients, respectively. Using physical examination findings as the reference measurements for volume overload, the area under the concentration curves for BCM and IVCD measurements were 0.866 (sensitivity 82%, specificity 74%, p < 0.001) and 0.727 (sensitivity 57%, specificity 70%, p < 0.001), respectively. Lean tissue index, inflammation, and atherosclerosis were associated with volume overload. CONCLUSIONS: Volume overload and malnutrition were common across the spectrum of South African CKD cohorts; volume overload was associated with malnutrition, inflammation, and atherosclerosis. Bioimpedance spectroscopy (BIS) is a useful and sensitive tool for the assessment of fluid status in clinically euvolumic nondialytic CKD patients.

Correlation between volume overload, chronic inflammation, and left ventricular dysfunction in chronic kidney disease patients.

BACKGROUND: Fluid overload is common in chronic kidney disease (CKD) patients, potentially driving chronic inflammation and left ventricular dysfunction. We investigated the association between volume overload, chronic inflammation, and left ventricular dysfunction across subgroups of CKD patients. METHODS: The study included 160 participants, comprising peritoneal dialysis (PD), hemodialysis (HD), stage-3 CKD patients, and age- and sex-matched controls (40 in each group). Fluid status was assessed using a body composition monitor (BCM); serum endotoxin, lipopolysaccharide binding protein (LBP), C-reactive protein (CRP). and interleukin-6 (IL-6) levels were measured as markers of inflammation. Echocardiography was done to assess left ventricular dimension and function. RESULTS: Endotoxemia and volume overload were common across the spectrum of CKD patients and were aggravated by worsening kidney function. Among HD cohorts, postdialysis endotoxemia was increased among patients with dialysis-induced hemodynamic instability and was also closely related to ultrafiltration volume. Endotoxin, IL-6, CRP, and LBP levels were elevated in patients with volume overload compared to euvolemic patients (p < 0.05). Patients with elevated circulating endotoxemia had higher left ventricular mass index (LVMI) compared to patients with lower endotoxin levels. Fluid overload correlated with endotoxin levels, IL-6, and LVMI; while LVMI correlated weakly with LBP and CRP. CONCLUSION: CKD patients typically presented with significant endotoxemia and overt volume overload, which may contribute significantly to chronic low-grade inflammation and left ventricular dysfunction. An additive contribution from hemodialysis treatment may strongly enhance the severity of endotoxemia in HD patients.

APOL1 Risk Variants Are Strongly Associated with HIV-Associated Nephropathy in Black South Africans.

APOL1 variants are associated with HIV-associated nephropathy and FSGS in African Americans. The prevalence of these variants in African populations with CKD in HIV-1 infection has not been investigated. We determined the role of APOL1 variants in 120 patients with HIV-associated nephropathy and CKD and 108 controls from a South-African black population. Patients with CKD were selected on the basis of histology. Genotypes were successfully determined for APOL1 G1 and G2 variants and 42 single nucleotide polymorphisms, including 18 ancestry informative markers, for 116 patients with CKD (96.7%; 38 patients with HIV-associated nephropathy, 39 patients with HIV-positive CKD, and 39 patients with HIV-negative CKD), and 108 controls (100%). Overall, 79% of patients with HIV-associated nephropathy and 2% of population controls carried two risk alleles. In a recessive model, individuals carrying any combination of two APOL1 risk alleles had 89-fold higher odds (95% confidence interval, 18 to 912; P<0.001) of developing HIV-associated nephropathy compared with HIV-positive controls. Population allele frequencies were 7.3% for G1 and 11.1% for G2. APOL1 risk alleles were not significantly associated with other forms of CKD. These results indicate HIV-positive, antiretroviral therapy-naïve South-African blacks with two APOL1 risk alleles are at very high risk for developing HIV-associated nephropathy. Further studies are required to determine the effect of APOL1 risk variants on kidney diseases in other regions of sub-Saharan Africa.

Calcium ions and osteoclastogenesis initiate the induction of bone formation by coral-derived macroporous constructs.

Coral-derived calcium carbonate/hydroxyapatite macroporous constructs of the genus Goniopora with limited hydrothermal conversion to hydroxyapatite (7% HA/CC) initiate the induction of bone formation. Which are the molecular signals that initiate pattern formation and the induction of bone formation? To evaluate the role of released calcium ions and osteoclastogenesis, 7% HA/CC was pre-loaded with either 500 µg of the calcium channel blocker, verapamil hydrochloride, or 240 µg of the osteoclast inhibitor, biphosphonate zoledronate, and implanted in the rectus abdominis muscle of six adult Chacma baboons Papio ursinus. Generated tissues on days 15, 60 and 90 were analysed by histomorphometry and qRT-PCR. On day 15, up-regulation of type IV collagen characterized all the implanted constructs correlating with vascular invasion. Zoledronate-treated specimens showed an important delay in tissue patterning and morphogenesis with limited bone formation. Osteoclastic inhibition yielded minimal, if any, bone formation by induction. 7% HA/CC pre-loaded with the Ca(++) channel blocker verapamil hydrochloride strongly inhibited the induction of bone formation. Down-regulation of bone morphogenetic protein-2 (BMP-2) together with up-regulation of Noggin genes correlated with limited bone formation in 7% HA/CC pre-loaded with either verapamil or zoledronate, indicating that the induction of bone formation by coral-derived macroporous constructs is via the BMPs pathway. The spontaneous induction of bone formation is initiated by a local peak of Ca(++) activating stem cell differentiation and the induction of bone formation.

Altered microRNA expression in patients with sarcoidosis.

Background Sarcoidosis is a granulomatous multisystem disease of uncertain aetiology. The disease has major inflammatory and immune components; however, the immunopathogenesis is not well understood. Micro ribonucleic acids (microRNAs) are classes of miniature, single-stranded, non-coding RNAs. Their key recognised role includes mediating the silencing of target genes post-transcriptionally. Recently, the role of miRNAs has gained interest in numerous disorders, suggested as being involved in pathogenesis of those diseases and acting as disease markers. Very little is known about the role of miRNAs in sarcoidosis, with nothing known regarding miRNAs in South African patients. The main objective, therefore, was to investigate the serum expression of approximately 800 miRNAs in patients with sarcoidosis compared with race-, age- and gender-matched healthy controls. Methods A total of six patients and six matched controls participated in this study. Whole blood samples were collected in EDTA tubes, processed and the plasma retained. RNA was extracted from the stored plasma samples using the QIAGEN miRNeasy Mini Kit® and concentrated using a salt-ethanol precipitation. The extracted miRNA was profiled using an nCounter® miRNA human v3 expression assay and data analysed using the nSolver™ Analysis Software. Results After excluding one sample/control pair because of cellular RNA contamination, the remaining five patient and five matched control samples were analysed, and 145 miRNAs were found to be potentially differentially expressed. On applying a Bonferroni correction, the only miRNA that was significantly different was miRNA let-7a-5p, which was significantly overexpressed (141-fold change; p<0.0003) in patients compared with controls. Conclusion This is the first miRNA report of differentially expressed miRNAs in the serum of patients with sarcoidosis and matched healthy controls in South Africa. The results obtained suggest that miRNAs may play a role in sarcoidosis pathogenesis. Whether these molecules have diagnostic or prognostic implications, needs future studies recruiting larger patient cohorts.

FGFR2 genetic variants in women with breast cancer.

Black African populations are more genetically diverse than others, but genetic variants have been studied primarily in European populations. The present study examined the association of four single nucleotide polymorphisms (SNPs) of the fibroblast growth factor receptor 2, associated with breast cancer in non­African populations, with breast cancer in Black, southern African women. Genomic DNA was extracted from whole blood samples of 1,001 patients with breast cancer and 1,006 controls (without breast cancer), and the rs2981582, rs35054928, rs2981578, and rs11200014 polymorphisms were analyzed using allele­specific Kompetitive allele­specific PCR™, and the χ2 or Fisher's exact tests were used to compare the genotype frequencies. There was no association between those SNPs and breast cancer in the studied cohort, although an association was identified between the C/C homozygote genotype for rs2981578 and invasive lobular carcinoma. These results show that genetic biomarkers of breast cancer risk in European populations are not necessarily associated with risk in sub­Saharan African populations. African populations are more heterogenous than other populations, and the information from this population can help focus genetic risks of cancer in this understudied population.

High risk APOL1 genotypes and kidney disease among treatment naïve HIV patients at Kano, Nigeria.

INTRODUCTION: Racial disparities are known in the occurrence of kidney disease with excess risks found among people of African descent. Apolipoprotein L1 (APOL1) gene variants G1 and G2 are associated with kidney disease among HIV infected individuals of African descent in the USA as well as among black population in South Africa. We set out to investigate the prevalence of these high-risk variants and their effects on kidney disease among HIV infected patients in Northern Nigeria with hitherto limited information despite earlier reports of high population frequencies of these alleles from the Southern part of the country. METHODS: DNA samples obtained from the whole blood of 142 participants were genotyped for APOL1 G1 and G2 variants after initial baseline investigations including assessment of kidney function. Participants comprised 50 HIV positive patients with no evidence of kidney disease, 52 HIV negative individuals with no kidney disease and 40 HIV positive patients with chronic kidney disease (CKD) evidenced by persistent proteinuria and/or reduced eGFR, who also had a kidney biopsy. All the HIV positive patients were newly diagnosed and treatment naïve. RESULTS: The distribution of the APOL1 genotypes among the study participants revealed that 24.6% had a G1 risk allele and 19.0% a G2. The frequency of the High Risk Genotype (HRG) was 12.5% among those with CKD compared to 5.8% in the HIV negative group and zero in the HIV positive no CKD group. Having the HRG was associated with a higher odds for developing HIV Associated Nephropathy (HIVAN) (2 vs 0 risk alleles: OR 10.83, 95% CI 1.38-84.52; P = 0.023; 2 vs 0 or 1 risk alleles: OR 5.5, 95% CI 0.83-36.29; P = 0.07). The HRG was also associated with higher odds for Focal Segmental Glomerulosclerosis (FSGS) (2 vs 0 risk alleles: OR 13.0, 95% CI 2.06-81.91; P = 0.006 and 2 vs 0 or 1 risk alleles: OR 9.0, 95%CI 1.62-50.12; P = 0.01) when compared to the control group. CONCLUSION: This study showed a high population frequency of the individual risk alleles of the APOL1 gene with higher frequencies noted among HIV positive patients with kidney disease. There is high association with the presence of kidney disease and especially FSGS and HIVAN among treatment naive HIV patients carrying two copies of the HRG.

Demographic and clinical profile of black patients with chronic kidney disease attending a tertiary hospital in Johannesburg, South Africa.

BACKGROUND: The prevalence of chronic kidney disease (CKD) is increasing worldwide; black patients have an increased risk of developing CKD and end stage kidney disease (ESKD) at significantly higher rates than other races. METHODS: A cross sectional study was carried out on black patients with CKD attending the kidney outpatient clinic at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in South Africa, between September 2019 to March 2020. Demographic and clinical data were extracted from the ongoing kidney outpatient clinic records and interviews, and were filled in a questionnaire. Patients provided blood and urine for laboratory investigations as standard of care, and data were descriptively and inferentially entered into REDcap and analysed using STATA version 17. Multivariable logistic regression analysis was used to identify demographic and clinical variables associated with advanced CKD. RESULTS: A total of 312 black patients with CKD were enrolled in the study with a median age of 58 (IQR 46-67) years; 58% patients had advanced CKD, 31.5% of whom had grossly increased proteinuria, 96.7% had hypertension, 38.7% had diabetes mellitus and 38.1% had both hypertension and diabetes mellitus. In patients with advanced CKD, the median age was 61 (IQR 51-69) years, eGFR 33 (30-39) mL/min/1.73 m2, serum bicarbonate 22 (IQR 20-24), haemoglobin 12.9 (IQR 11.5-14.0) g/dl and serum uric acid 0.43 (IQR 0.37-0.53). The prevalence of metabolic acidosis was 62.4%, anemia 46.4% and gout 30.9% among those with advanced CKD, while the prevalence of metabolic acidosis and anaemia was 46.6% and 25.9% respectively in those with early CKD. Variables with higher odds for advanced CKD after multivariable logistic regression analysis were hypertension (OR 3.3, 95% CI 1.2-9.2, P = 0.020), diabetes mellitus (OR 1.8, 95% CI 1.1-3.3, P = 0.024), severe proteinuria (OR 3.5, 95% CI 1.9-6.5, P = 0.001), angina (OR 2.5, 95% CI 1.2-5.1, P = 0.008), anaemia (OR 2.9, 95% CI 1.7-4.9, P = 0.001), hyperuricemia (OR 2.4, 95% CI 1.4-4.1, P = 0.001), and metabolic acidosis (OR 2.0, 95% CI 1.2-3.1, P = 0.005). Other associations with advanced CKD were loss of spouse (widow/widower) (OR 3.2, 95% CI 1.4-7.4, P = 0.006), low transferrin (OR 2.4, 95% CI 1.1-5.1, P = 0.028), hyperkalemia (OR 5.4, 95% CI 1.2-24.1, P = 0.029), use of allopurinol (OR 2.4, 95% CI 1.4-4.3, P = 0.005) and doxazosin (OR 1.9, 95% CI 1.2-3.1, P = 0.006). CONCLUSION: Hypertension and diabetes mellitus were strongly associated with advanced CKD, suggesting a need for primary and secondary population-based prevention measures. Metabolic acidosis, anemia with low transferrin levels, hyperuricemia and hyperkalemia were highly prevalent in our patients, including those with early CKD, and they were strongly associated with advanced CKD, requiring clinicians and dietitians to be proactive in supporting the needs of CKD patients in meeting their daily dietary requirements towards preventing and slowing the progression of CKD.

Survival of south african women with breast cancer receiving anti-retroviral therapy for HIV.

PURPOSE: Breast cancer outcomes in sub-Saharan Africa is reported to be poor, with an estimated five-year survival of 50% when compared to almost 90% in high-income countries. Although several studies have looked at the effect of HIV in breast cancer survival, the effect of ARTs has not been well elucidated. METHODS: All females newly diagnosed with invasive breast cancer from May 2015-September 2017 at Charlotte Maxeke Johannesburg Academic and Chris Hani Baragwanath Academic Hospital were enrolled. We analysed overall survival and disease-free survival, comparing HIV positive and negative patients. Kaplan-Meier survival curves were generated with p-values calculated using a log-rank test of equality while hazard ratios and their 95% confidence intervals (CIs) were estimated using Cox regression models. RESULTS: Of 1019 patients enrolled, 22% were HIV positive. The overall survival (95% CI) was 53.5% (50.1-56.7%) with a disease-free survival of 55.8% (52.1-59.3) after 4 years of follow up. HIV infection was associated with worse overall survival (HR (95% CI): 1.50 (1.22-1.85), p < 0.001) and disease-free survival (OR (95% CI):2.63 (1.71-4.03), p < 0.001), especially among those not on ART at the time of breast cancer diagnosis. Advanced stage of the disease and hormone-receptor negative breast cancer subtypes were also associated with poor survival. CONCLUSION: HIV infection was associated with worse overall and disease-free survival. HIV patients on ARTs had favourable overall and disease-free survival and with ARTs now being made accessible to all the outcome of women with HIV and breast cancer is expected to improve.

Profiling Biomarkers in HIV Glomerular Disease - Potential for the Non-Invasive Diagnosis of HIVAN?

BACKGROUND: There is a wide spectrum of kidney pathology in human immunodeficiency virus (HIV) infection, affecting all structures of the kidney. The histology of HIV chronic kidney disease (CKD) is diverse, ranging from HIV-associated nephropathy (HIVAN) to focal glomerulosclerosis (FSGS), HIV-immune complex disease (HIV-ICD), other glomerulopathies and tubulo-interstitial nephritis. Definitive diagnosis is by kidney biopsy, an invasive procedure. However, serum and urinary biomarkers may be useful in predicting the histological diagnosis of HIVAN. PURPOSE: We wished to determine the utility of serum and urinary biomarkers in predicting the histological diagnosis of HIVAN. PATIENTS AND METHODS: We measured neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, transforming growth factor (TGF)-ß isoforms and bone morphogenetic protein (BMP)-7 in the serum and urine in patients with different histological forms of HIV glomerular disease. RESULTS: In HIVAN, we demonstrated increased levels of serum cystatin C and increased levels of serum and urinary NGAL. Urinary TGF-ß1 and TGF-ß2 levels were elevated in HIV-positive patients with CKD but were not significantly different in the different HIV histologies, while urinary BMP-7 levels were elevated in minimal change disease. CONCLUSION: This study confirmed the presence of increased serum and urinary biomarkers of tubular injury in patients with HIVAN, and increased urinary biomarkers of fibrosis in HIV CKD, and may indicate their value as a non-invasive diagnostic tool for the diagnosis of HIVAN.

Endothelial dysfunction in HIV-positive patients with acute coronary syndromes.

AIM: This study investigated endothelial function in HIV-positive patients with acute coronary syndrome (ACS). Flow-mediated dilatation, pulse-wave velocity, carotid intima-media thickness and endothelial biomarkers were used to non-invasively investigate endothelial dysfunction. METHODS: Twenty HIV-positive patients with ACS (HIV+/ACS) were compared to 20 HIV-negative patients with ACS (HIV-/ACS) and 20 HIV-positive patients without ACS (HIV+/no ACS). RESULTS: Endothelial function measured by flow-mediated dilatation (FMD) was similar in both the HIV+/ACS (5.2; IQR 1.4-13.4%) and HIV-/ACS groups (3.7; IQR 2.3-4.4%) (p = 0.78). Arterial stiffness, measured by pulse-wave velocity (PWV) was low in all three cohorts. Carotid intima-media thickness (CIMT) was also low in all three cohorts. The vascular cellular adhesion molecule-1 (VCAM-1) levels in HIV-positive patients with and without ACS were significantly higher than in the HIV-/ACS cohort (p = 0.033 and 0.024, respectively). CONCLUSIONS: Non-invasive investigations such as FMD, CIMT and PWV did not identify patients with HIV who were at high risk of ACS. Endothelial biomarkers may be more useful markers to identify HIV-positive patients who have endothelial dysfunction and increased risk of ACS.

Biomarkers for Diagnosis and Prediction of Outcomes in Contrast-Induced Nephropathy.

BACKGROUND: Serum creatinine is suboptimal as a biomarker in the early diagnosis of contrast-induced nephropathy (CIN). In this study, we investigated a panel of novel biomarkers in the early diagnosis of CIN and in assessing patient outcomes. METHODS: This single-centre, nested, prospective case-controlled study included 30 patients with CIN and 60 matched controls. Serum and urine samples were collected before contrast administration and at 24 hours, 48 hours, and ≥5 days after contrast administration. Concentrations of NGAL, cystatin C, ß 2M, IL18, IL10, KIM1, and TNFα were determined using Luminex and ELISA assays. Outcomes were biomarker diagnostic discrimination performance for CIN and mortality after generation of area under receiver operating characteristic curves (AUROCs). RESULTS: Median serum levels for 24 h cystatin C (p < 0.01) and 48 h ß 2M levels (p < 0.001) and baseline urine NGAL (p=0.02) were higher in CIN patients compared to controls with AUROCs of 0.75, 0.78, and 0.74, respectively, for the early diagnosis of CIN. Serum ß 2M levels were higher in CIN patients at all time points. Elevated baseline serum concentrations of IL18 (p < 0.001), ß 2M (p=0.04), TNFα (p < 0.001), and baseline urine KIM (p=0.01) and 24 h urine NGAL (p=0.02) were significantly associated with mortality. Baseline serum concentrations of IL18, ß 2M, and TNFα showed the best discrimination performance for mortality with AUROCs, all >0.80. Baseline NGAL was superior for excluding patients at risk for CIN, with positive and negative predictive ranges of 0.50-0.55 and 0.81-0.88, respectively. Cystatin C (p=0.003) and ß 2M (p=0.03) at 24 h independently predicted CIN risk. ß 2M predicted increased mortality of 40% at baseline and 50% at 24 hours. CONCLUSION: Serum cystatin C at 24 h was the best biomarker for CIN diagnosis, while baseline levels of serum IL18, ß 2M, and TNFα were best for predicting prognosis.

Biofilm formation and induction of stress response genes is a common response of several serotypes of the pneumococcus to cigarette smoke condensate.

OBJECTIVES: Exposure to cigarette smoke impacts on the virulence of Streptococcus pneumoniae (pneumococcus) by mechanisms including induction of biofilm formation. Most studies, however, have focused on individual strains of the pneumococcus. Accordingly, the current study has investigated the commonality of the pneumococcal stress response to cigarette smoke condensate (CSC), using five different strains of the pathogen. METHODS: Following exposure to CSC at final concentrations of 80 and 160 µg mL-1 during a 16 h incubation period, biofilm formation was measured using a crystal violet-based spectrophotometric procedure. Expression of stress genes seemingly linked to biofilm formation viz. hk11 and rr11 [histidine kinase and response regulator of the two-component regulatory system 11 (TCS11) respectively], cat eff (cation efflux system protein), abc (ATP-binding component of an ATP-binding cassette transporter) and 2005-hyp (hypothetical gene) was measured by sequential extraction of RNA, cDNA synthesis and real-time qPCR. RESULTS: Exposure of all five strains of the pneumococcus to CSC, resulted in significant biofilm formation, as well as induction of all five test stress genes. CONCLUSIONS: Augmentation of induction of selective stress genes and biofilm formation are common, possibly linked, responses of various serotypes of the pneumococcus to CSC, favouring both persistence of the pathogen and decreased efficacy of antibiotics.