Browsing by Author "Cotton, Mark"

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    Adherence to isoniazid prophylaxis among HIV-infected children: a randomized controlled trial comparing two dosing schedules
    (BioMed Central Ltd, 2009) le Roux, Stanzi; Cotton, Mark; Golub, Jonathan; le Roux, David; Workman, Lesley; Zar, Heather
    BACKGROUND:Tuberculosis contributes significantly to morbidity and mortality among HIV-infected children in sub-Saharan Africa. Isoniazid prophylaxis can reduce tuberculosis incidence in this population. However, for the treatment to be effective, adherence to the medication must be optimized. We investigated adherence to isoniazid prophylaxis administered daily, compared to three times a week, and predictors of adherence amongst HIV-infected children. METHODS: We investigated adherence to study medication in a two centre, randomized trial comparing daily to three times a week dosing of isoniazid. The study was conducted at two tertiary paediatric care centres in Cape Town, South Africa. Over a 5 year period, we followed 324 HIV-infected children aged [greater than or equal to] 8 weeks. Adherence information based on pill counts was available for 276 children. Percentage adherence was calculated by counting the number of pills returned. Adherence [greater than or equal to] 90% was considered to be optimal. Analysis was done using summary and repeated measures, comparing adherence to the two dosing schedules. Mean percentage adherence (per child during follow-up time) was used to compare the mean of each group as well as the proportion of children achieving an adherence of [greater than or equal to] 90% in each group. For repeated measures, percentage adherence (per child per visit) was dichotomized at 90%. A logistic regression model with generalized estimating equations, to account for within-individual correlation, was used to evaluate the impact of the dosing schedule. Adjustments were made for potential confounders and we assessed potential baseline and time-varying adherence determinants. RESULTS: The overall adherence to isoniazid was excellent, with a mean adherence of 94.7% (95% confidence interval [CI] 93.5-95.9); similar mean adherence was achieved by the group taking daily medication (93.8%; 95% CI 92.1-95.6) and by the three times a week group (95.5%; 95% CI 93.8-97.2). Two-hundred and seventeen (78.6%) children achieved a mean adherence of [greater than or equal to] 90%. Adherence was similar for daily and three times a week dosing schedules in univariate (odds ratio [OR] 0.88; 95% CI 0.66-1.17; P = 0.38) and multivariate (adjusted OR 0.85; 95% CI 0.64-1.11; P = 0.23) models. Children from overcrowded homes were less adherent (adjusted OR 0.71; 95% CI 0.54-0.95; P = 0.02). Age at study visit was predictive of adherence, with better adherence achieved in children older than 4 years (adjusted OR 1.96; 95% CI 1.16-3.32; P = 0.01). CONCLUSION: Adherence to isoniazid was excellent regardless of the dosing schedule used. Intermittent dosing of isoniazid prophylaxis can be considered as an alternative to daily dosing, without compromising adherence or efficacy.TRIAL REGISTRATION:Clinical Trials NCT00330304
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    Early Antiretroviral Therapy reduces the incidence of otorrhea in a randomized study of early and deferred antiretroviral therapy: Evidence from the Children with HIV Early Antiretroviral Therapy (CHER) Study
    (BioMed Central Ltd, 2011) Hainline, Clotilde; Taliep, Reghana; Sorour, Gill; Nachman, Sharon; Rabie, Helena; Dobbels, Els; van Rensburg, Anita; Cornell, Morna; Violari, Avy; Madhi, Shabir; Cotton, Mark
    BACKGROUND: Although otorrhea occurs commonly in HIV-infected infants, there are few data. We compared the incidence of otorrhea in infants receiving early vs deferred ART in the Children with HIV Early Antiretroviral (CHER) trial. Infants aged 6 to 12 weeks of age with confirmed HIV infection and a CD4 percentage greater than or equal to 25% were randomized to early or deferred ART at two sites in South Africa. Medical records from one study site were reviewed for otorrhea.FINDINGS:Data were reviewed from the start of the trial in July 2005 until 20 June 2007, when the Data Safety Monitoring Board recommended that randomization to the deferred arm should stop and that all infants in this arm be reviewed for commencing antiretroviral therapy. Infants entered the study at a median of 7.4 weeks of age. Eleven of 38 (29%) on deferred therapy and 7 of 75 (9%) in the early-therapy group developed otorrhea (risk ratio 3.1, 95% confidence interval (CI) 1.31-7.36; p = 0.01). CONCLUSIONS: Early initiation of antiretroviral therapy is associated with significantly less otorrhea than when a deferred strategy is followed.TRIAL REGISTRATION:NCT00102960. ClinicalTrials.Gov
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    Emergence of a peak in early infant mortality due to HIV/AIDS in South Africa
    (2009) Bourne, David E; Thompson, MaryLou; Brodya, Linnea L; Cotton, Mark; Draper, Beverly; Laubscher, Ria; Abdullah, M Fareed; Myers, Jonny E
    Objectives: South Africa has among the highest levels of HIV prevalence in the world. Our objectives are to describe the distribution of South African infant and child mortality by age at fine resolution, to identify any trends over recent time and to examine these trends for HIV-associated and non HIV-associated causes of mortality. Methods: A retrospective review of vital registration data was conducted. All registered postneonatal deaths under 1 year of age in South Africa for the period 1997–2002 were analysed by age in months using a generalized linear model with a log link and Poisson family. Results: Postneonatal mortality increased each year over the period 1997–2002. A peak in HIV-related deaths was observed, centred at 2–3 months of age, rising monotonically over time. Conclusion: We interpret the peak in mortality at 2–3 months as an indicator for paediatric AIDS in a South African population with high HIV prevalence and where other causes of death are not sufficiently high to mask HIV effects. Intrauterine and intrapartum infection may contribute to this peak. It is potentially a useful surveillance tool, not requiring an exact cause of death. The findings also illustrate the need for early treatment of mother and child in settings with very high HIV prevalence.
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    High incidence of antimicrobial resistant organisms including extended spectrum beta-lactamase producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus in nasopharyngeal and blood isolates of HIV-infected children from Cape Town, South Africa
    (BioMed Central Ltd, 2008) Cotton, Mark; Wasserman, Elizabeth; Smit, Juanita; Whitelaw, Andrew; Zar, Heather
    BACKGROUND:There is little information on nasopharyngeal (NP) flora or bacteremia in HIV-infected children. Our aim was to describe the organisms and antimicrobial resistance patterns in children enrolled in a prospective study comparing daily and three times weekly trimethoprim-sulfamethoxazole (TMP-SMX) and isoniazid (INH) or placebo prophylaxis. METHODS: NP swabs were taken at baseline from HIV-infected children enrolled in the study. Standard microbiological techniques were used. Children were grouped according to previous or current exposure to TMP-SMX and whether enrolled to the study during a period of hospitalization. Blood culture results were also recorded within 12 months of baseline. RESULTS: Two hundred and three children, median age 1.8 (Interquartile [IQ]: 0.7-4) years had NP swabs submitted for culture. One hundred and eighty-four (90.7%) had either stage B or C HIV disease. One hundred and forty-one (69.8%) were receiving TMP-SMX and 19 (9.4%) were on antiretroviral therapy. The majority, 168 (82%) had a history of hospitalization and 91 (44.8%) were enrolled during a period of hospitalization. Thirty-two subjects (16.2%) died within 12 months of study entry.One hundred and eighty-one potential pathogens were found in 167 children. The most commonly isolated organisms were Streptococcus pneumoniae (48: 22.2%), Gram-negative respiratory organisms (Haemophilus influenzae and Moraxella catarrhalis) (47: 21.8%), Staphylococcus aureus (44: 20.4%), Enterobacteriaceae 32 (14.8%) and Pseudomonas 5 (2.3%).Resistance to TMP-SMX occurred in > 80% of pathogens except for M. catarrhalis (2: 18.2% of tested organisms). TMP-SMX resistance tended to be higher in those receiving it at baseline (p = 0.065). Carriage of Methicillin resistant S. aureus (MRSA) was significantly associated with being on TMP-SMX at baseline (p = 0.002). Minimal inhibitory concentrations (MIC) to penicillin were determined for 18 S. pneumoniae isolates: 7 (38.9%) were fully sensitive (MIC [less than or equal to] 0.06 mug/ml), 9 (50%) had intermediate resistance (MIC 0.12 - 1 mug/ml) and 2 (11.1%) had high level resistance (MIC [greater than or equal to]2 mug/ml). Fifty percent of Enterobacteriaceae produced extended spectrum beta-lactamases (ESBL) (resistant to third generation cephalosporins) and 56% were resistant to gentamicin. Seventy-seven percent of S. aureus were MRSA. Carriage of resistant organisms was not associated with hospitalization.On multivariate logistic regression, risk factors for colonization with Enterobacteriaceae were age [less than or equal to] one year (Odds ratio 4.4; 95% Confidence Interval 1.9-10.9; p = 0.0008) and CDC stage C disease (Odds ratio 3.6; 95% Confidence Interval 1.5-8.6; p = 0.005)Nineteen (9.4%) subjects had 23 episodes of bacteremia. Enterobacteriaceae were most commonly isolated (13 of 25 isolates), of which 6 (46%) produced ESBL and were resistant to gentamicin. CONCLUSION: HIV-infected children are colonized with potential pathogens, most of which are resistant to commonly used antibiotics. TMP-SMX resistance is extremely common. Antibiotic resistance is widespread in colonizing organisms and those causing invasive disease. Antibiotic recommendations should take cognizance of resistance patterns. Antibiotics appropriate for ESBL-producing Enterobacteriaceae and MRSA should be used for severely ill HIV-infected children in our region. Further study of antibiotic resistance patterns in HIV-infected children from other areas is needed.
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    It is time to consider third-line options in antiretroviral-experienced paediatric patients?
    (BioMed Central Ltd, 2011) van Zyl, Gert; Rabie, Helena; Nuttall, James; Cotton, Mark
    BACKGROUND: The historic use of full-dose ritonavir as part of an unboosted protease inhibitor (PI)-based antiretroviral therapy regimen in some South African children contributes to the frequent accumulation of major PI resistance mutations. METHODS: In order to describe the prevalence of major PI resistance in children failing antiretroviral therapy and to investigate the clinical, immunological and virological outcomes in children with PI resistance, we conducted a cross-sectional study, with a nested case series, following up those children with major PI resistance. The setting was public health sector antiretroviral clinics in the Western Cape province of South Africa, and the subjects were children failing antiretroviral therapy. The following outcome measures were investigated: CD4 count, viral load and resistance mutations. RESULTS: Fourteen (17%) of 82 patients, referred from tertiary hospitals, had major PI resistance. All these patients were exposed to regimens that included ritonavir as a single PI. Immune reconstitution and clinical benefit were achieved when using a lopinavir/ritonavir-based treatment regimen in these children with prior PI resistance. At first HIV-1 viral load follow up after initial resistance testing (n = 11), only one patient had a viral load of less than 400 copies/ml; at a subsequent follow up (n = 9), the viral loads of five patients were less than 400 copies/ml. Patients retained on LPV/r had lower viral loads than those switched to a non-nucleoside reverse transcriptase inhibitor (NNRTI). However, two of three patients with follow-up resistance tests accumulated additional PI resistance. CONCLUSIONS: In children with pre-existing PI resistance, although initially effective, the long-term durability of a lopinavir/ritonavir-based treatment regimen can be compromised by the accumulation of resistance mutations. Furthermore, a second-line NNRTI regimen is often not durable in these patients. As genotypic resistance testing and third-line treatment regimens are costly and limited in availability, we propose eligibility criteria to identify patients with high risk for resistance and guidance on drug selection for children who would benefit from third-line therapy.
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    Paediatric HIV disclosure in South Africa - caregivers' perspectives on discussing HIV with infected children
    (2006) Moodley, Keymanthri; Myer, Landon; Michaels, Desiree; Cotton, Mark
    Most paediatric HIV infections in South Africa are transmitted perinatally. Lack of widely available HIV treatment means that most children do not survive to an age at which disclosure becomes a relevant concern. However, with the expansion of HIV treatment programmes the proportion of HIV-infected children surviving to an advanced age is likely to increase substantially during the next 5 - 10 years. A similar phenomenon was observed in Europe and North America with the advent of antiretroviral therapy (ART) in the mid-1990s, and in resource-rich settings approximately half of perinatally infected children are expected to survive beyond 13 years of age.1
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    Shorter treatment for minimal tuberculosis (TB) in children (SHINE): a study protocol for a randomised controlled trial
    (BioMed Central, 2018-04-19) Chabala, Chishala; Turkova, Anna; Thomason, Margaret J; Wobudeya, Eric; Hissar, Syed; Mave, Vidya; van der Zalm, Marieke; Palmer, Megan; Kapasa, Monica; Bhavani, Perumal K; Balaji, Sarath; Raichur, Priyanka A; Demers, Anne-Marie; Hoddinott, Graeme; Owen-Powell, Ellen; Kinikar, Aarti; Musoke, Philippa; Mulenga, Veronica; Aarnoutse, Rob; McIlleron, Helen; Hesseling, Anneke; Crook, Angela M; Cotton, Mark; Gibb, Diana M
    Background: Tuberculosis (TB) in children is frequently paucibacillary and non-severe forms of pulmonary TB are common. Evidence for tuberculosis treatment in children is largely extrapolated from adult studies. Trials in adults with smear-negative tuberculosis suggest that treatment can be effectively shortened from 6 to 4 months. New paediatric, fixed-dose combination anti-tuberculosis treatments have recently been introduced in many countries, making the implementation of World Health Organisation (WHO)-revised dosing recommendations feasible. The safety and efficacy of these higher drug doses has not been systematically assessed in large studies in children, and the pharmacokinetics across children representing the range of weights and ages should be confirmed. Methods/design: SHINE is a multicentre, open-label, parallel-group, non-inferiority, randomised controlled, two-arm trial comparing a 4-month vs the standard 6-month regimen using revised WHO paediatric anti-tuberculosis drug doses. We aim to recruit 1200 African and Indian children aged below 16 years with non-severe TB, with or without HIV infection. The primary efficacy and safety endpoints are TB disease-free survival 72 weeks post randomisation and grade 3 or 4 adverse events. Nested pharmacokinetic studies will evaluate anti-tuberculosis drug concentrations, providing model-based predictions for optimal dosing, and measure antiretroviral exposures in order to describe the drug-drug interactions in a subset of HIV-infected children. Socioeconomic analyses will evaluate the cost-effectiveness of the intervention and social science studies will further explore the acceptability and palatability of these new paediatric drug formulations. Discussion: Although recent trials of TB treatment-shortening in adults with sputum-positivity have not been successful, the question has never been addressed in children, who have mainly paucibacillary, non-severe smearnegative disease. SHINE should inform whether treatment-shortening of drug-susceptible TB in children, regardless of HIV status, is efficacious and safe. The trial will also fill existing gaps in knowledge on dosing and acceptability of new anti-tuberculosis formulations and commonly used HIV drugs in settings with a high burden of TB. A positive result from this trial could simplify and shorten treatment, improve adherence and be cost-saving for many children with TB. Recruitment to the SHINE trial begun in July 2016; results are expected in 2020. Trial registration: International Standard Randomised Controlled Trials Number: ISRCTN63579542, 14 October 2014. Pan African Clinical Trials Registry Number: PACTR201505001141379, 14 May 2015. Clinical Trial Registry-India, registration number: CTRI/2017/07/009119, 27 July 2017.
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    Spectrum, progression and predictors of morbidity in perinatally HIV-infected adolescents on antiretroviral therapy
    (2021) Frigati, Lisa Jane; Zar, Heather J; Myer, Landon; Cotton, Mark
    Background: Long term survival of children living with HIV due to improved early access to antiretroviral therapy (ART) is contributing to a growing population of adolescents living with perinatally acquired HIV (PHIV+) at risk of developing chronic multisystem comorbidity. There is limited knowledge on the overall burden, progression and causes of morbidity in PHIV+ adolescents, especially in resource limited settings. Much of what is known about morbidity in PHIV+ adolescents relates to single organ system pathology and there is a lack of a holistic approach to PHIV+ adolescents and their overall health. The aim of this PhD project was therefore to investigate the spectrum and determinants of chronic morbidity, the progression of disease and intercurrent illness in PHIV+ adolescents on ART over a 4- year period. Methods: This was a prospective study of participants enrolled in the Cape Town Adolescent Antiretroviral Cohort (CTAAC), a longitudinal cohort study, that recruited 515 PHIV+ adolescents and 110 HIV negative (HIV-) adolescents matched by age from 7 health care sites in Cape Town, South Africa. Eligibility criteria included PHIV+ adolescents who were aged 9-14 years, who had been on ART for at least 6 months and were aware of their HIV status. All adolescents and caregivers gave informed consent/assent. Participants were followed 6-monthly with questionnaires, clinical examination with detailed pulmonary (lung function), neurocognitive (magnetic resonance imaging and a battery of neurocognitive tests), cardiovascular (echocardiogram and ECG) and laboratory investigations. Analyses for each specific objective of the PhD were developed. Three analyses used data from the enrolment visit and were primarily descriptive and two were longitudinal and examined the incidence of hospitalizations, QuantiFERON conversion (an interferon gamma release assay used to measure Mycobacterium tuberculosis infection) and Tuberculosis (TB) disease. Results: Five hundred fifteen PHIV+ and 109 HIV- participants had a median follow-up of 4.1 years (IQR: 3.7–4.6). At enrollment, PHIV+ adolescents had a median duration of ART of 7.6 years (IQR: 4.6–9.2), median CD4 count of 713 cells/mm3 (IQR: 561.0–957.5) and 387 (75%) had a viral load of <50 copies/mL. Neurocognitive impairment was present in more than half of the PHIV+ cohort (56.3% vs. 45.3% in HIV-, p=0.05) but renal impairment was rare (2.3% in PHIV+ vs. 2.1% in HIV-, p=0.89). Microalbuminuria was also rare (8.0 in PHIV+ vs. 9.0% in HIV-, p=0.80). Respiratory or cardiac impairment were more common in PHIV+ adolescents than in HIV- participants (27.1% vs. 14.7%, p=0.01 and 46.1% vs. 33.7%, p=0.03, respectively). Multisystem impairment (defined as impairment of ≥ 3 systems) was uncommon, with only 10% of PHIV+ adolescents having 4-system impairment. Metabolic abnormalities, such as insulin resistance (IR), were relatively common but IR rates did not differ compared to HIV- adolescents (18 vs. 20%, p= 0.17). Incidence rates for hospitalization were 6.6 per 100-person-years (PY) in PHIV+ adolescents, three times that of HIV- adolescents. Sixty percent of hospitalization episodes were due to non-infectious causes and 24% due to infectious causes, of which pneumonia and TB were the predominant causes. PHIV+ adolescents had a substantially higher incidence of TB disease than HIV- adolescents (2.2/100 PY, 95% CI 1.6-3.1 vs. 0.3/100 PY, 95% CI 0.04-2.2), despite a similar rate of TB infection, as measured by QuantiFERON positivity. TB disease was associated with low CD4 counts and high viral loads in PHIV+ adolescents. Conclusion: Chronic single system morbidity experienced by PHIV+ adolescents on ART was common and merits further study, as this population begins to engage in adult lifestyle factors, such as smoking and alcohol use, that may compound these abnormalities. However, multisystem morbidity was relatively rare. In addition, in a relatively small percentage of adolescents there were subclinical metabolic abnormalities (IR and microalbuminuria) that may result in increased morbidity especially with regards to diabetes and cardiovascular disease in later life. The high burden of hospitalization and intercurrent disease, mainly due to TB, could be prevented by proven strategies, such as TB preventive therapy and ensuring adherence to optimal ART regimens.
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    Utility of clinical parameters to identify HIV infection in infants below ten weeks of age in South Africa: a prospective cohort study
    (BioMed Central Ltd, 2011) Jaspan, Heather; Myer, Landon; Madhi, Shabir; Violari, Avy; Gibb, Diana; Stevens, Wendy; Dobbels, Els; Cotton, Mark
    BACKGROUND:As HIV-infected infants have high mortality, the World Health Organization now recommends initiating antiretroviral therapy as early as possible in the first year of life. However, in many settings, laboratory diagnosis of HIV in infants is not readily available. We aimed to develop a clinical algorithm for HIV presumptive diagnosis in infants < 10 weeks old using screening data from the Children with HIV Early Antiretroviral therapy (CHER) study in South Africa.HIV-infected and HIV-uninfected exposed infants < 10 weeks of age were identified through Vertical Transmission Prevention programs. Clinical and laboratory data were systematically recorded, groups were compared using Kruskal-Wallis, analysis of variance (ANOVA), and Fisher's exact tests. Receiver Operating Characteristic (ROC) curves were compiled using combinations of clinical findings. RESULTS: 417 HIV-infected and 125 HIV-exposed, uninfected infants, median age 46 days (IQR 38-55), were included. The median CD4 percentage in HIV-infected infants was 34 (IQR 28-41)%. HIV-infected infants had lower weight-for-age, more lymphadenopathy, oral thrush, and hepatomegaly than exposed uninfected infants (Adjusted Odds Ratio 0.51, 8.8, 5.6 and 23.5 respectively; p < 0.001 for all). Sensitivity of individual signs was low (< 20%) but specificity high (98-100%). If any one of oral thrush, hepatomegaly, splenomegaly, lymphadenopathy, diaper dermatitis, weight < 50th centile are present, sensitivity for HIV infection amongst HIV-exposed infants was 86%. These algorithms performed similarly when used to predict severe immune suppression. CONCLUSIONS: A combination of physical findings is helpful in identifying infants most likely to be HIV-infected. This may inform management algorithms and provide guidance for focused laboratory testing in some settings, and should be further validated in these settings and elsewhere.