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1.
BMC Infect Dis ; 23(1): 67, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737689

RESUMO

BACKGROUND: Candida bloodstream infection (BSI) causes appreciable mortality in neonates and children. There are few studies describing the epidemiology of Candida BSI in children living in sub-Saharan Africa. METHODS: A retrospective descriptive study was conducted at three public sector hospitals in Cape Town, South Africa. Demographic and clinical details, antifungal management and patient outcome data were obtained by medical record review. Candida species distribution and antifungal susceptibility testing results were obtained from the National Health Laboratory Service database. RESULTS: Of the 97 Candida BSI episodes identified during a five-year period, 48/97 (49%) were Candida albicans (C. albicans), and 49/97 (51%) were non-C. albicans species. The overall incidence risk was 0.8 Candida BSI episodes per 1000 admissions at Red Cross War Memorial Children's Hospital. Of the 77/97 (79%) Candida BSI episodes with available clinical information, the median age (interquartile range) at the time of BSI was 7 (1-25) months, 36/77 (47%) were associated with moderate or severe underweight-for-age and vasopressor therapy was administered to 22/77 (29%) study participants. Most of the Candida BSI episodes were healthcare-associated infections, 63/77 (82%). Fluconazole resistance was documented among 17%, 0% and 0% of C. parapsilosis, C. tropicalis and C. albicans isolates, respectively. All Candida isolates tested were susceptible to amphotericin B and the echinocandins. The mortality rate within 30 days of Candida BSI diagnosis was 13/75 (17%). On multivariable analysis, factors associated with mortality within 30 days of Candida BSI diagnosis included vasopressor therapy requirement during Candida BSI, adjusted Odds ratio (aOR) 53 (95% confidence interval 2-1029); hepatic dysfunction, aOR 13 (95% CI 1-146); and concomitant bacterial BSI, aOR 10 (95% CI 2-60). CONCLUSION: The study adds to the limited number of studies describing paediatric Candida BSI in sub-Saharan Africa. Non-C. Albicans BSI episodes occurred more frequently than C. albicans episodes, and vasopressor therapy requirement, hepatic dysfunction and concomitant bacterial BSI were associated with an increase in 30-day mortality.


Assuntos
Candidemia , Candidíase , Sepse , Recém-Nascido , Criança , Humanos , Lactente , Candida , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , África do Sul/epidemiologia , Estudos Retrospectivos , Setor Público , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Candidíase/microbiologia , Sepse/tratamento farmacológico , Hospitais Públicos , Candida albicans , Candida parapsilosis , Candida tropicalis , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica , Candidemia/tratamento farmacológico , Candidemia/epidemiologia , Candidemia/microbiologia
2.
BMC Infect Dis ; 20(1): 729, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028225

RESUMO

BACKGROUND: This study describes the disease burden, clinical characteristics, antibiotic management, impact of multidrug resistance and outcome of Pseudomonas aeruginosa bloodstream infection (PABSI) among children admitted to a tertiary referral hospital for children in Cape Town, South Africa. METHODS: A retrospective descriptive study was conducted at a paediatric referral hospital in Cape Town, South Africa. Demographic and clinical details, antibiotic management and patient outcome information were extracted from medical and laboratory records. Antibiotic susceptibility results of identified organisms were obtained from the National Health Laboratory Service database. RESULTS: The incidence risk of PABSI was 5.4 (95% CI: 4.34-6.54) PABSI episodes / 10,000 hospital admissions and the most common presenting feature was respiratory distress, 34/91 (37.4%). Overall, 69/91 (75.8%) of the PA isolates were susceptible to all antipseudomonal antibiotic classes evaluated. Fifty (54.9%) of the PABSI episodes were treated with appropriate empiric antibiotic therapy. The mortality rate was 24.2% and in multivariable analysis, empiric antibiotic therapy to which PA isolates were not susceptible, infections present on admission, and not being in the intensive care unit at the time that PABSI was diagnosed were significantly associated with 14-day mortality. CONCLUSIONS: PABSI caused appreciable mortality, however, appropriate empiric antibiotic therapy was associated with reduced 14-day mortality.


Assuntos
Infecções por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Farmacorresistência Bacteriana/efeitos dos fármacos , Feminino , Hospitais Pediátricos , Humanos , Lactente , Unidades de Terapia Intensiva , Masculino , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/mortalidade , Pseudomonas aeruginosa/efeitos dos fármacos , Estudos Retrospectivos , África do Sul/epidemiologia , Taxa de Sobrevida , Centros de Atenção Terciária
3.
Clin Infect Dis ; 68(10): 1658-1664, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30203002

RESUMO

BACKGROUND: Congenital rubella syndrome (CRS) includes disorders associated with intrauterine rubella infection. Incidence of CRS is higher in countries with no rubella-containing vaccines (RCV) in their immunization schedules. In the World Health Organization African region, RCVs are being introduced as part of the 2012-2020 global measles and rubella strategic plan. This study aimed to describe the epidemiology of confirmed CRS in South Africa prior to introduction of RCVs in the immunization schedule. METHODS: This was a descriptive study with 28 sentinel sites reporting laboratory-confirmed CRS cases in all 9 provinces of South Africa. In the retrospective phase (2010 to 2014), CRS cases were retrieved from medical records, and in the prospective phase (2015 to 2017) clinicians at study sites reported CRS cases monthly. RESULTS: There were 42 confirmed CRS cases in the retrospective phase and 53 confirmed CRS cases in the prospective phase. Most frequently reported birth defects were congenital heart disease and cataracts. The median age of mothers of CRS cases was 21 years in the retrospective phase (range: 11 to 38 years) and 22 years in the prospective phase (range: 15 to 38 years). CONCLUSION: Baseline data on laboratory-confirmed CRS will enable planning and monitoring of RCV implementation in the South African Expanded Programme on Immunization program. Ninety-eight percent of mothers of infants with CRS were young women 14-30 years old, indicating a potential immunity gap in this age group for consideration during introduction of RCV.


Assuntos
Anticorpos Antivirais/sangue , Complicações Infecciosas na Gravidez/prevenção & controle , Síndrome da Rubéola Congênita/epidemiologia , Síndrome da Rubéola Congênita/prevenção & controle , Vigilância de Evento Sentinela , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Prontuários Médicos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Estudos Prospectivos , Pesquisa Qualitativa , Estudos Retrospectivos , Vírus da Rubéola , África do Sul , Adulto Jovem
4.
AIDS Behav ; 22(3): 909-917, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29224045

RESUMO

Accurate measurement of antiretroviral therapy (ART) adherence remains challenging and there are few data assessing the validity of self-reported adherence among perinatally HIV-infected adolescents. We examined adolescent and caregiver reports of adolescent adherence among perinatally-infected adolescents aged 9-14 years in Cape Town, South Africa, and explored factors that may modify associations between reported adherence and elevated viral load (VL). Among 474 adolescents (median age 12.0 years; median duration of ART use 7.5 years), elevated VL and caregiver- and adolescent-report of missed ART doses were common. Elevated VL was particularly prevalent among older, male adolescents. Low-moderate concordance was observed between caregiver and adolescent report. Among adolescents aged ≥ 12 years, caregiver- and adolescent-reported adherence was associated with elevated VL across most items assessed, but few significant associations were observed among adolescents < 12 years of age. Refined adherence measures and tools to identify adolescents who require adherence interventions are needed in this context.


Assuntos
Terapia Antirretroviral de Alta Atividade , População Negra/estatística & dados numéricos , Cuidadores/psicologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Carga Viral/efeitos dos fármacos , Adolescente , População Negra/psicologia , Criança , Estudos Transversais , Feminino , Infecções por HIV/etnologia , Humanos , Masculino , Adesão à Medicação/etnologia , Adesão à Medicação/psicologia , Adesão à Medicação/estatística & dados numéricos , Manejo da Dor , Autorrelato , Testes Sorológicos , África do Sul/epidemiologia
5.
BMC Infect Dis ; 17(1): 750, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29207958

RESUMO

BACKGROUND: Bloodstream infection (BSI) in children causes significant morbidity and mortality. There are few studies describing the epidemiology of BSI in South African children. METHODS: A retrospective descriptive cohort study was conducted at a paediatric referral hospital in Cape Town, South Africa. The National Health Laboratory Service (NHLS) microbiology database was accessed to identify positive blood culture specimens during the period 2011-2012. Demographic and clinical details, antimicrobial management and patient outcome information were extracted from medical and laboratory records. Antibiotic susceptibility results of identified organisms were obtained from the NHLS database. RESULTS: Of the 693 unique bacterial and fungal BSI episodes identified during the study period, 248 (35.8%) were community-acquired (CA), 371 (53.5%) hospital-acquired (HA) and 74 (10.7%) healthcare-associated (HCA). The overall risk was 6.7 BSI episodes per 1000 admissions. Escherichia coli, Staphylococcus aureus and Streptococcus pneumoniae were the most frequent causes of CA-BSI and Klebsiella pneumoniae, Acinetobacter baumanii and S.aureus were most commonly isolated in HA-BSI. On multivariable analysis, severe underweight, severe anaemia at the time of BSI, admission in the ICU at the time of BSI, and requiring ICU admission after BSI was diagnosed were significantly associated with 14-day mortality. CONCLUSION: This study adds to the limited literature describing BSI in children in Africa. Further studies are required to understand the impact that BSI has on the paediatric population in sub-Saharan Africa.


Assuntos
Bacteriemia/diagnóstico , Anemia/complicações , Anemia/diagnóstico , Bacteriemia/complicações , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Criança , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Feminino , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/isolamento & purificação , Hospitais Pediátricos , Humanos , Unidades de Terapia Intensiva , Masculino , Análise Multivariada , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Risco , África do Sul/epidemiologia , Centros de Atenção Terciária , Magreza/complicações , Magreza/diagnóstico
6.
EMBO J ; 31(13): 2852-68, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22643220

RESUMO

Peroxisomes undergo rapid, selective autophagic degradation (pexophagy) when the metabolic pathways they contain are no longer required for cellular metabolism. Pex3 is central to the formation of peroxisomes and their segregation because it recruits factors specific for these functions. Here, we describe a novel Saccharomyces cerevisiae protein that interacts with Pex3 at the peroxisomal membrane. We name this protein Atg36 as its absence blocks pexophagy, and its overexpression induces pexophagy. We have isolated pex3 alleles blocked specifically in pexophagy that cannot recruit Atg36 to peroxisomes. Atg36 is recruited to mitochondria if Pex3 is redirected there, where it restores mitophagy in cells lacking the mitophagy receptor Atg32. Furthermore, Atg36 binds Atg8 and the adaptor Atg11 that links receptors for selective types of autophagy to the core autophagy machinery. Atg36 delivers peroxisomes to the preautophagosomal structure before being internalised into the vacuole with peroxisomes. We conclude that Pex3 recruits the pexophagy receptor Atg36. This reinforces the pivotal role played by Pex3 in coordinating the size of the peroxisome pool, and establishes its role in pexophagy in S. cerevisiae.


Assuntos
Proteínas de Membrana/metabolismo , Peroxissomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Autofagia/fisiologia , Família da Proteína 8 Relacionada à Autofagia , Proteínas Relacionadas à Autofagia , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Peroxinas , Ligação Proteica , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/genética , Vacúolos/metabolismo , Proteínas de Transporte Vesicular/metabolismo
7.
BMC Infect Dis ; 16: 236, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27246848

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection in young children in both the community and hospital setting. METHODS: The clinical presentation, patient and phylogenetic characteristicsof laboratory-confirmed cases of RSV, as well as risk factors for nosocomial infectionat Red Cross War Memorial Children's Hospital in Cape Town were analysed. A multiplex PCR assay that detects 7 respiratory viruses was used to identify RSV nucleic acid on respiratory specimens. RESULTS: A total of 226 children were studied, ages ranging between 1 week and 92.5 months (median: 2.8 months, IQR: 1.3-6.3 months) and 51.8 % were males. The median duration of symptoms prior to diagnosis was 2 days (IQR: 1-4 days). Nosocomial infections wereidentified in 22 (9.7 %) children. There were pre-existing medical conditions in 113 (50.0 %) excluding HIV, most commonly prematurity (n = 58, 50.0 %) and congenital heart disease (n = 34, 29.3 %). The commonest presenting symptoms were cough (196, 86.7 %), difficulty in breathing (115, 50.9 %) and fever (91, 41.6 %).A case fatality rate of 0.9 % was recorded. RSV group A predominated (n = 181, 80.1 %) while group B accounted for only 45 (19.9 %) of the infections. The prevalent genotypes were NA1 (n = 127,70.1 %), ON1 (n = 45,24.9 %) and NA2 (n = 9,5.0 %) for group A while the only circulating RSV B genotype was BA4. There was no significant difference in the genotype distribution between the nosocomial and community-acquired RSV infections. Age ≥ 6 months was independently associated with nosocomial infection. CONCLUSIONS: A large percentage of children with RSV infection had pre-existing conditions. Approximately one tenth of the infections were nosocomial with age 6 months or older being a risk factor. Though both RSV groups co-circulated during the season, group A was predominant and included the novel ON1 genotype. Continued surveillance is necessary to identify prevalent and newly emerging genotypes ahead of vaccine development and efficacy studies.


Assuntos
Criança Hospitalizada , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/isolamento & purificação , Criança , Criança Hospitalizada/estatística & dados numéricos , Pré-Escolar , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/virologia , Feminino , Genótipo , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Filogenia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/classificação , África do Sul/epidemiologia
8.
Glob Chang Biol ; 21(7): 2670-2686, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25482824

RESUMO

The response of wheat crops to elevated CO2 (eCO2 ) was measured and modelled with the Australian Grains Free-Air CO2 Enrichment experiment, located at Horsham, Australia. Treatments included CO2 by water, N and temperature. The location represents a semi-arid environment with a seasonal VPD of around 0.5 kPa. Over 3 years, the observed mean biomass at anthesis and grain yield ranged from 4200 to 10 200 kg ha-1 and 1600 to 3900 kg ha-1 , respectively, over various sowing times and irrigation regimes. The mean observed response to daytime eCO2 (from 365 to 550 µmol mol-1 CO2 ) was relatively consistent for biomass at stem elongation and at anthesis and LAI at anthesis and grain yield with 21%, 23%, 21% and 26%, respectively. Seasonal water use was decreased from 320 to 301 mm (P = 0.10) by eCO2 , increasing water use efficiency for biomass and yield, 36% and 31%, respectively. The performance of six models (APSIM-Wheat, APSIM-Nwheat, CAT-Wheat, CROPSYST, OLEARY-CONNOR and SALUS) in simulating crop responses to eCO2 was similar and within or close to the experimental error for accumulated biomass, yield and water use response, despite some variations in early growth and LAI. The primary mechanism of biomass accumulation via radiation use efficiency (RUE) or transpiration efficiency (TE) was not critical to define the overall response to eCO2 . However, under irrigation, the effect of late sowing on response to eCO2 to biomass accumulation at DC65 was substantial in the observed data (~40%), but the simulated response was smaller, ranging from 17% to 28%. Simulated response from all six models under no water or nitrogen stress showed similar response to eCO2 under irrigation, but the differences compared to the dryland treatment were small. Further experimental work on the interactive effects of eCO2 , water and temperature is required to resolve these model discrepancies.

9.
Clin Orthop Relat Res ; 472(1): 8-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24081669

RESUMO

BACKGROUND: Benign and malignant lower extremity primary bone tumors are among the least common conditions treated by orthopaedic surgeons. The literature supporting their surgical management has historically been in the form of observational studies rather than prospective controlled studies. Observational studies are prone to confounding bias, sampling bias, and recall bias. QUESTIONS/PURPOSES: (1) What are the overall levels of evidence of articles published on the surgical management of lower extremity bone tumors? (2) What is the overall quality of reporting of studies in this field based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist? (3) What are the most common pitfalls in reporting that authors might improve on? METHODS: All studies describing the surgical management of lower extremity primary bone tumors from 2002 to 2012 were systematically reviewed. Two authors independently appraised levels of evidence. Quality of reporting was assessed with the STROBE checklist. Pitfalls in reporting were quantified by determining the 10 most underreported elements of research study design in the group of studies analyzed, again using the STROBE checklist as the reference standard. Of 1387 studies identified, 607 met eligibility criteria. RESULTS: There were no Level I studies, two Level II studies, 47 Level III studies, 308 Level IV studies, and 250 Level V studies. The mean percentage of STROBE points reported satisfactorily in each article as graded by the two reviewers was 53% (95% confidence interval, 42%-63%). The most common pitfalls in reporting were failures to justify sample size (2.2% reported), examine sensitivity (2.2%), account for missing data (9.8%), and discuss sources of bias (14%). Followup (66%), precision of outcomes (64%), eligibility criteria (55%), and methodological limitations (53%) were variably reported. CONCLUSIONS: Observational studies are the dominant evidence for the surgical management of primary lower extremity bone tumors. Numerous deficiencies in reporting limit their clinical use. Authors may use these results to inform future work and improve reporting in observational studies, and treating surgeons should be aware of these limitations when choosing among the various options with their patients.


Assuntos
Neoplasias Ósseas/cirurgia , Medicina Baseada em Evidências , Extremidade Inferior/cirurgia , Editoração/normas , Humanos
10.
J Bone Miner Res ; 39(3): 211-221, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38477739

RESUMO

Randomized controlled trials (RCTs) to determine the influence of vitamin D on BMC and fracture risk in children of Black African ancestry are lacking. We conducted a sub-study (n = 450) nested within a phase 3 RCT of weekly oral supplementation with 10 000 IU vitamin D3 vs placebo for 3 yr in HIV-uninfected Cape Town schoolchildren aged 6-11 yr. Outcomes were BMC at the whole body less head (WBLH) and LS and serum 25-hydroxyvitamin D3 (25(OH)D3), PTH, alkaline phosphatase, C-terminal telopeptide, and PINP. Incidence of fractures was a secondary outcome of the main trial (n = 1682). At baseline, mean serum 25(OH)D3 concentration was 70.0 nmol/L (SD 13.5), and 5.8% of participants had serum 25(OH)D3 concentrations <50 nmol/L. Among sub-study participants, end-trial serum 25(OH)D3 concentrations were higher for participants allocated to vitamin D vs placebo (adjusted mean difference [aMD] 39.9 nmol/L, 95% CI, 36.1 to 43.6) and serum PTH concentrations were lower (aMD -0.55 pmol/L, 95% CI, -0.94 to -0.17). However, no interarm differences were seen for WBLH BMC (aMD -8.0 g, 95% CI, -30.7 to 14.7) or LS BMC (aMD -0.3 g, 95% CI, -1.3 to 0.8) or serum concentrations of bone turnover markers. Fractures were rare among participants in the main trial randomized to vitamin D vs placebo (7/755 vs 10/758 attending at least 1 follow-up; adjusted odds ratio 0.70, 95% CI, 0.27 to 1.85). In conclusion, a 3-yr course of weekly oral vitamin D supplementation elevated serum 25(OH)D3 concentrations and suppressed serum PTH concentrations in HIV-uninfected South African schoolchildren of Black African ancestry but did not influence BMC or serum concentrations of bone turnover markers. Fracture incidence was low, limiting power to detect an effect of vitamin D on this outcome.


Vitamin D­the "sunshine vitamin"­is essential for helping the body to absorb calcium from the diet, which is laid down in bone to improve its strength. There is a lack of clinical trials testing whether vitamin D supplements can improve bone content of calcium and other minerals, or reduce risk of bone fractures (broken bones) in children of Black African ancestry. We therefore conducted such a study, recruiting 1682 schoolchildren aged 6­11 yr living in Cape Town, South Africa. We found that a weekly dose of 10 000 international units (250 micrograms) of vitamin D3, given by mouth for 3 yr, was effective in boosting vitamin D levels in trial participants who received it. However, this did not have any effect on bone content of calcium and other minerals. Relatively few children experienced a broken bone during the study, so we were unable to say with confidence whether or not vitamin D supplements might affect this outcome.


Assuntos
Fraturas Ósseas , Infecções por HIV , Deficiência de Vitamina D , Criança , Humanos , Densidade Óssea , Remodelação Óssea , Calcifediol/farmacologia , Colecalciferol/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Fraturas Ósseas/tratamento farmacológico , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/prevenção & controle , Infecções por HIV/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , África do Sul/epidemiologia , Vitamina D , Deficiência de Vitamina D/tratamento farmacológico , População Negra , População da África Austral
11.
BMJ Paediatr Open ; 8(1)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599800

RESUMO

OBJECTIVE: To determine whether weekly oral vitamin D supplementation influences growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. DESIGN: Phase 3 double-blind randomised placebo-controlled trial. SETTING: Socioeconomically disadvantaged peri-urban district of Cape Town, South Africa. PARTICIPANTS: 1682 children of black African ancestry attending government primary schools and aged 6-11 years at baseline. INTERVENTIONS: Oral vitamin D3 (10 000 IU/week) versus placebo for 3 years. MAIN OUTCOME MEASURES: Height-for-age and body mass index-for-age, measured in all participants; Tanner scores for pubertal development, spirometric lung volumes and body composition, measured in a subset of 450 children who additionally took part in a nested substudy. RESULTS: Mean serum 25-hydroxyvitamin D3 concentration at 3-year follow-up was higher among children randomised to receive vitamin D versus placebo (104.3 vs 64.7 nmol/L, respectively; mean difference (MD) 39.7 nmol/L, 95% CI 37.6 to 41.9 nmol/L). No statistically significant differences in height-for-age z-score (adjusted MD (aMD) -0.08, 95% CI -0.19 to 0.03) or body mass index-for-age z-score (aMD -0.04, 95% CI -0.16 to 0.07) were seen between vitamin D versus placebo groups at follow-up. Among substudy participants, allocation to vitamin D versus placebo did not influence pubertal development scores, % predicted forced expiratory volume in 1 s (FEV1), % predicted forced vital capacity (FVC), % predicted FEV1/FVC, fat mass or fat-free mass. CONCLUSIONS: Weekly oral administration of 10 000 IU vitamin D3 boosted vitamin D status but did not influence growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. TRIAL REGISTRATION NUMBERS: ClinicalTrials.gov NCT02880982, South African National Clinical Trials Register DOH-27-0916-5527.


Assuntos
Colestanos , Deficiência de Vitamina D , Criança , Humanos , Composição Corporal , Colecalciferol/uso terapêutico , Colestanos/uso terapêutico , Suplementos Nutricionais , África do Sul/epidemiologia , Espirometria , Vitamina D/uso terapêutico , Deficiência de Vitamina D/tratamento farmacológico , Vitaminas/uso terapêutico , Método Duplo-Cego
12.
Biochem J ; 447(3): 353-61, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22849378

RESUMO

NBP (nitrogen-containing bisphosphonate) drugs protect against excessive osteoclast-mediated bone resorption. After binding to bone mineral, they are taken up selectively by the osteoclasts and inhibit the essential enzyme FDPS (farnesyl diphosphate synthase). NBPs inhibit also growth of amoebae of Dictyostelium discoideum in which their target is again FDPS. A fusion protein between FDPS and GFP (green fluorescent protein) was found, in D. discoideum, to localize to peroxisomes and to confer resistance to the NBP alendronate. GFP was also directed to peroxisomes by a fragment of FDPS comprising amino acids 1-22. This contains a sequence of nine amino acids that closely resembles the nonapeptide PTS2 (peroxisomal targeting signal type 2): there is only a single amino acid mismatch between the two sequences. Mutation analysis confirmed that the atypical PTS2 directs FDPS into peroxisomes. Furthermore, expression of the D. discoideum FDPS-GFP fusion protein in strains of Saccharomyces cerevisiae defective in peroxisomal protein import demonstrated that import of FDPS into peroxisomes was blocked in a strain lacking the PTS2-dependent import pathway. The peroxisomal location of FDPS in D. discoideum indicates that NBPs have to cross the peroxisomal membrane before they can bind to their target.


Assuntos
Dictyostelium/metabolismo , Difosfonatos/farmacologia , Geraniltranstransferase/metabolismo , Peroxissomos/metabolismo , Alendronato/farmacologia , Sequência de Aminoácidos , Sequência Consenso , Dictyostelium/genética , Resistência a Medicamentos , Geraniltranstransferase/genética , Proteínas de Fluorescência Verde/genética , Mutagênese Sítio-Dirigida , Mutação , Receptor 2 de Sinal de Orientação para Peroxissomos , Receptor 1 de Sinal de Orientação para Peroxissomos , Transporte Proteico , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais
13.
AIDS ; 37(3): 435-445, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36695356

RESUMO

INTRODUCTION: Studies examining hospitalization among infants with HIV in resource-limited settings, in the context of early infant diagnosis and early antiretroviral therapy (ART) initiation, are limited. METHODS: We used routinely collected data on infants who initiated ART aged <3 months (Western Cape province, South Africa; 2013-2017) to describe hospitalization from birth until 12 months post-ART initiation. Record reviews were additionally performed at three tertiary-level facilities. We used mixed-effects Poisson regression to examine factors associated with hospitalization. RESULTS: Among 840 infants, 579 (69%) were hospitalized; 36% had >1 hospitalization. Median age at ART initiation decreased from 57 days (interquartile range [IQR] 22-74; 2013-2015) to 19 days (IQR 5-54; 2016-2017). Early neonatal hospitalization (age <7 days) occurred in 271 infants (32%) and represented 24% of hospitalizations (272/1131). Overall, 443 infants (53%) were hospitalized at age ≥7 days, including 13% with hospitalizations pre-ART initiation, 15% pre and post-ART initiation and 25% post-ART initiation. Excluding early neonatal hospitalizations, initiating ART at older age vs. age <1 week was associated with higher hospitalization rates: adjusted incidence rate ratios (95% confidence interval) were 1.86 (1.31-2.64); 2.31 (1.62-3.29) and 2.47 (1.76-3.46) if ART initiation age was 1-4 weeks; 5-8 weeks and 9-12 weeks respectively. Among infants whose hospital records were reviewed, reasons for early neonatal hospitalizations mostly related to prematurity or low birthweight (n = 46/60; 77%) whereas hospitalizations at age ≥7 days were mostly due to infections (n = 206/243; 85%). CONCLUSIONS: Earlier ART initiation is associated with lower hospitalization rates. High hospitalization rates, despite initiation age <3 months, is concerning.


Assuntos
Infecções por HIV , Recém-Nascido , Gravidez , Feminino , Lactente , Humanos , Infecções por HIV/epidemiologia , Antirretrovirais/uso terapêutico , África do Sul/epidemiologia , Parto , Hospitalização
14.
S Afr J Infect Dis ; 38(1): 528, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38058658

RESUMO

Background: Antimicrobial stewardship principles guide the clinical use of antimicrobials, including vancomycin, but paediatric vancomycin prescribing practices have not been evaluated in South Africa. Objectives: To document the use, prescribing practices and monitoring of intravenous vancomycin and the spectrum of bacteria isolated on microbiological culture in children treated with intravenous vancomycin during a 12-month period at Red Cross War Memorial Children's Hospital (RCWMCH). Method: A retrospective audit of intravenous vancomycin use in children admitted to RCWMCH during 2019 was performed. Results: All 158 vancomycin prescription episodes for 143 children were included. Overall usage of intravenous vancomycin was 63 days of therapy per 1000 patient days (interquartile range [IQR]: 38-72). The median starting dose was 15 mg/kg per dose (IQR: 14-15) and median daily dose was 45 mg/kg per day (IQR: 43-60). Vancomycin was prescribed as empiric (127/158, 80%) and directed (31/158, 20%) treatment. The median duration of treatment for the directed group (7 days) was longer than the empiric group (4 days) (p = 0.001). Vancomycin serum trough concentrations were performed in 65/98 (66%) episodes where vancomycin treatment exceeded 3 days, with only 16/65 (25%) of these samples obtained before the fourth dose. Prolonged antibiotic treatment of 14 days or more was not associated with Gram-positive bacteria on culture (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 0.17-4.2). Conclusion: Dosing errors, prolonged empiric treatment and inappropriate vancomycin monitoring were problems associated with vancomycin prescriptions. Contribution: The study identified multiple opportunities for improved vancomycin prescribing and monitoring. Further research and implementation of improved prescribing practices could contribute to the preservation of vancomycin as an effective antibiotic.

15.
Int J Infect Dis ; 134: 63-70, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37211272

RESUMO

OBJECTIVES: To determine whether weekly oral supplementation with 10,000 IU vitamin D3 for 3 years reduces the risk of sensitization to M. tuberculosis in South African schoolchildren aged 6-11 years with negative QuantiFERON-tuberculosis (TB) Gold Plus (QFT-Plus) assay results at baseline. METHODS: We conducted a phase 3 randomized placebo-controlled trial in 1682 children attending 23 primary schools in Cape Town. The primary outcome was a positive end-trial QFT-Plus result, analyzed using a mixed effects logistic regression model with the school of attendance included as a random effect. RESULTS: 829 vs. 853 QFT-Plus-negative children were randomized to receive vitamin D3 vs. placebo, respectively. Mean end-study 25(OH)D concentrations in participants randomized to vitamin D vs. placebo were 104.3 vs 64.7 nmol/l, respectively (95% confidence interval for difference, 37.6 to 41.9 nmol/l). A total of 76/667 (11.4%) participants allocated to vitamin D vs. 89/687 (13.0%) participants allocated to placebo tested QFT-Plus positive at 3-year follow-up (adjusted odds ratio 0.86, 95% confidence interval 0.62-1.19, P = 0.35). CONCLUSION: Weekly oral supplementation with 10,000 IU vitamin D3 for 3 years elevated serum 25(OH)D concentrations among QFT-Plus-negative Cape Town schoolchildren but did not reduce their risk of QFT-Plus conversion.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Criança , Humanos , África do Sul/epidemiologia , Suplementos Nutricionais , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/prevenção & controle , Vitamina D , Colecalciferol/uso terapêutico , Vitaminas/uso terapêutico , Tuberculose Latente/tratamento farmacológico , Método Duplo-Cego
16.
S Afr J Infect Dis ; 37(1): 398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35815226

RESUMO

Background: Microbiological confirmation of pulmonary tuberculosis (PTB) in children is a well-documented challenge. This study evaluated Xpert Mycobacterium Tuberculosis (MTB)/Rifampicin (RIF) Ultra (Ultra) and mycobacterial cultures in routine clinical care at a tertiary paediatric hospital. Methods: Children treated for PTB and who had at least one respiratory specimen investigated by Ultra and mycobacterial culture before tuberculosis (TB) treatment was commenced were included. The findings of this retrospective study were summarised using descriptive and inferential statistics. Results: A total of 174 children were included. The median age was 2.5 years. Microcytic anaemia, airway compression, cavitary disease and miliary TB were significantly observed in children with microbiologically confirmed TB (cTB). Tuberculosis was microbiologically confirmed in 93 (53.4%) children. The positive yield from testing the first respiratory specimens was 68/174 (39.1%) on Ultra and 82/174 (47.1%) on combined Ultra and mycobacterial culture. In the subset of children (n = 70) tested with Ultra on two sequential respiratory specimens, the incremental yield from the second specimen was 30.3%. In the subset of children (n = 16) tested with Ultra on three sequential respiratory specimens, the incremental yield from the second and third specimens was 16.7% and 0.0%, respectively. When Ultra and mycobacterial culture results were combined, the incremental yield in children who had two sequential respiratory specimens tested was 24.4% and 3.1% on Ultra and mycobacterial culture, respectively. Conclusion: Ultra and mycobacterial culture on a single respiratory specimen resulted in a high microbiological yield. Ultra-testing on a second respiratory specimen increased the yield of microbiologically cTB. Additional diagnostic testing may require further study.

17.
S Afr J Infect Dis ; 37(1): 440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935170

RESUMO

The increased incidence and absence of antibiotic treatment options for New Delhi metallo-ß-lactamase (NDM)-producing carbapenem-resistant Enterobacterales (CRE) infection are concerning. Recent reports have highlighted NDM-producing Serratia marcescens, as a specific concern, as it is an organism which is intrinsically resistant to colistin. In this study, a descriptive analysis of NDM-producing CRE infections was performed at the Red Cross War Memorial Children's Hospital.

18.
Nutrients ; 14(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35334921

RESUMO

Vitamin D deficiency (25-hydroxyvitamin D[25(OH)D] <50 nmol/L) is common among adults in Cape Town, South Africa, but studies investigating vitamin D status of children in this setting are lacking. We conducted a cross-sectional study to determine the prevalence and determinants of vitamin D deficiency in 1825 Cape Town schoolchildren aged 6−11 years. Prevalence of vitamin D deficiency was 7.6% (95% Confidence Interval [CI] 6.5% to 8.9%). Determinants of vitamin D deficiency included month of sampling (adjusted odds ratio [aOR] for July−September vs. January−March 10.69, 95% CI 5.02 to 22.77; aOR for October−December vs. January−March 6.73, 95% CI 2.82 to 16.08), older age (aOR 1.25 per increasing year, 95% CI: 1.01−1.53) and higher body mass index (BMI; aOR 1.24 per unit increase in BMI-for-age Z-score, 95% CI: 1.03−1.49). In a subset of 370 participants in whom parathyroid hormone (PTH) concentrations were measured; these were inversely related to serum 25(OH)D concentrations (p < 0.001). However, no association between participants with hyperparathyroidism (PTH >6.9 pmol/L) and vitamin D deficiency was seen (p = 0.42). In conclusion, we report that season is the major determinant of vitamin D status among Cape Town primary schoolchildren, with prevalence of vitamin D deficiency ranging from 1.4% in January−March to 22.8% in July−September.


Assuntos
Deficiência de Vitamina D , Criança , Estudos Transversais , Humanos , Hormônio Paratireóideo , Prevalência , África do Sul/epidemiologia
19.
J Pediatric Infect Dis Soc ; 11(12): 578-581, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36041049

RESUMO

We report the first case of Balamuthia mandrillaris granulomatous amoebic encephalitis definitively acquired in Africa. Our case emphasizes initial nonspecific dermatological features, delays in confirmation of the diagnosis, difficulties accessing recommended medication, and uncertainty about optimal treatment of a disease with a frequently fatal outcome.


Assuntos
Amebíase , Balamuthia mandrillaris , Encefalite , Encefalite Infecciosa , Humanos , População Africana , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Encéfalo , Encefalite/diagnóstico , Encefalite/tratamento farmacológico , Evolução Fatal , Granuloma , Encefalite Infecciosa/diagnóstico , Encefalite Infecciosa/tratamento farmacológico , Pré-Escolar
20.
South Afr J HIV Med ; 22(1): 1283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691770

RESUMO

Antiretroviral treatment has undergone major changes in the last 20 years, from monotherapy, to dual therapy and finally to triple therapy. Lately, more focus has been placed on better, more well-tolerated combinations and formulations. As in most other disciplines in medicine, the development of paediatric HIV dosages and formulations always tends to lag behind adult research. Twenty years ago, it could take several years before data were available to enable the use of life-saving antiretrovirals in children. Paediatricians, being ever resourceful, were not prepared to let their paediatric patients suffer despite the lack of data or formulations and so made a plan. This article describes some of the trials and tribulations that we went through trying to make sure that our paediatric HIV patients not only survived but thrived. Clinicians treating paediatric patients today have it so much easier because of what our colleagues and their patients went through in those early days.

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