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Featured researches published by Chandy C. John.


Open Forum Infectious Diseases | 2016

Acute Kidney Injury Is Common in Pediatric Severe Malaria and Is Associated With Increased Mortality

Andrea L. Conroy; Michael Hawkes; Robyn E. Elphinstone; Catherine Morgan; Laura Hermann; Kevin R. Barker; Sophie Namasopo; Robert O. Opoka; Chandy C. John; W. Conrad Liles; Kevin C. Kain

Acute kidney injury is common in severe malaria and associated with short- and long-term mortality developing in 50% of cases after admission. Cystatin C and BUN are associated with the severity of AKI, are elevated at admission and predict mortality.


The Journal of Infectious Diseases | 2016

Alterations in Systemic Extracellular Heme and Hemopexin Are Associated With Adverse Clinical Outcomes in Ugandan Children With Severe Malaria

Robyn E. Elphinstone; Andrea L. Conroy; Michael Hawkes; Laura Hermann; Sophie Namasopo; H. Shaw Warren; Chandy C. John; W. Conrad Liles; Kevin C. Kain

Background. Malaria remains a major cause of global mortality. Extracellular heme, released during malaria-induced hemolysis, mediates a number of pathogenic processes associated with vascular and organ injury. Hemopexin (hpx) facilitates the degradation of extracellular heme. In this study, we explore the hypothesis that dysregulation of the heme-hpx axis is associated with disease severity, acute kidney injury (AKI), and outcome. Methods. Plasma levels of hemin and hpx (at admission, day 3, and day 14) were assessed in children with severe malaria in Jinja, Uganda. Results. The ratio of heme to hpx was higher at admission and decreased with recovery (median, 0.043 [interquartile range {IQR}, 0.007–0.239] on day 1, 0.024 [IQR, 0.005–0.126] on day 3, and 0.008 [IQR, 0.002–0.022] on day 14; P < .001). Ratios of heme to hpx at admission were higher in children with as compared to those without severe anemia (median, 0.124 [IQR, 0.024–0.431] vs 0.016 [IQR, 0.003–0.073]; P < .0001), children with as compared to those without respiratory distress (median, 0.063 [IQR, 0.017–0.413] vs 0.020 [IQR, 0.004–0.124]; P < .01), and children with as opposed to those without stage 3 AKI (median, 0.354 [IQR, 0.123–2.481] vs 0.037 [IQR, 0.005–0.172], P < .01). The heme to hpx ratio at admission was associated with 6-month mortality (median, 0.148 [IQR, 0.042–0.500] vs 0.039 [IQR, 0.007–0.172]; P = .012). Conclusions. The ratio of heme to hpx is associated with disease severity and adverse clinical outcomes in Ugandan children, and dysregulation of the heme axis may contribute to malaria pathogenesis.


The American Journal of Clinical Nutrition | 2014

Decline in childhood iron deficiency after interruption of malaria transmission in highland Kenya.

Anne E.P. Frosch; Bartholomew N. Ondigo; George Ayodo; John M. Vulule; Chandy C. John; Sarah E. Cusick

BACKGROUND Achieving optimal iron status in children in malaria-endemic areas may increase the risk of malaria. Malaria itself may contribute to iron deficiency, but the impact of an interruption in malaria transmission on the prevalence of iron deficiency is unknown. OBJECTIVES We aimed to determine whether 1) iron status improved in children living in 2 Kenyan villages with a documented cessation in malaria transmission and 2) changes in iron status correlated with changes in hemoglobin. DESIGN We measured iron [hemoglobin, ferritin, soluble transferrin receptor (sTfR)] and inflammatory [C-reactive protein (CRP)] markers in paired plasma samples from 190 children aged 4-59 mo at the beginning (May 2007) and end (July 2008) of a documented 12-mo period of interruption in malaria transmission in 2 highland areas in Kenya with unstable malaria transmission and ongoing malaria surveillance. RESULTS Between May 2007 and July 2008, mean (±SD) hemoglobin increased from 10.8 ± 1.6 to 11.6 ± 1.6 g/dL. Median (25th, 75th percentile) ferritin increased from 17.0 (9.7, 25.6) to 22.6 (13.4, 34.7) μg/L (P < 0.001), whereas median sTfR decreased from 32.4 (26.3, 43.2) to 27.7 (22.1, 36.0) nmol/L (P < 0.001). Median CRP was low (<1 mg/L in both years) and did not change significantly. Iron deficiency prevalence (ferritin <12 μg/L, or <30 μg/L if CRP ≥10 mg/L) decreased from 35.9% (95% CI: 28.9%, 43.0%) to 24.9% (18.5%, 31.2%) (P = 0.005). The prevalence of iron deficiency with anemia (hemoglobin <11.0 g/dL) declined from 27.2% (20.7%, 33.8%) to 12.2% (7.4%, 17.1%) (P < 0.001). Improvement in iron status correlated with an increase in hemoglobin and was greater than explained by physiologic changes expected with age. CONCLUSIONS In this area of unstable malaria transmission, the prevalence of iron deficiency in children decreased significantly after the interruption of malaria transmission and was correlated with an increase in hemoglobin. These findings suggest that malaria elimination strategies themselves may be an effective way to address iron deficiency in malaria-endemic areas.


Blood | 2017

Novel use Of Hydroxyurea in an African Region with Malaria (NOHARM): a trial for children with sickle cell anemia

Robert O. Opoka; Christopher Ndugwa; Teresa Latham; Adam Lane; Heather Hume; Phillip Kasirye; James S. Hodges; Russell E. Ware; Chandy C. John

Hydroxyurea treatment is recommended for children with sickle cell anemia (SCA) living in high-resource malaria-free regions, but its safety and efficacy in malaria-endemic sub-Saharan Africa, where the greatest sickle-cell burden exists, remain unknown. In vitro studies suggest hydroxyurea could increase malaria severity, and hydroxyurea-associated neutropenia could worsen infections. NOHARM (Novel use Of Hydroxyurea in an African Region with Malaria) was a randomized, double-blinded, placebo-controlled trial conducted in malaria-endemic Uganda, comparing hydroxyurea to placebo at 20 ± 2.5 mg/kg per day for 12 months. The primary outcome was incidence of clinical malaria. Secondary outcomes included SCA-related adverse events (AEs), clinical and laboratory effects, and hematological toxicities. Children received either hydroxyurea (N = 104) or placebo (N = 103). Malaria incidence did not differ between children on hydroxyurea (0.05 episodes per child per year; 95% confidence interval [0.02, 0.13]) vs placebo (0.07 episodes per child per year [0.03, 0.16]); the hydroxyurea/placebo malaria incidence rate ratio was 0.7 ([0.2, 2.7]; P = .61). Time to infection also did not differ significantly between treatment arms. A composite SCA-related clinical outcome (vaso-occlusive painful crisis, dactylitis, acute chest syndrome, splenic sequestration, or blood transfusion) was less frequent with hydroxyurea (45%) than placebo (69%; P = .001). Children receiving hydroxyurea had significantly increased hemoglobin concentration and fetal hemoglobin, with decreased leukocytes and reticulocytes. Serious AEs, sepsis episodes, and dose-limiting toxicities were similar between treatment arms. Three deaths occurred (2 hydroxyurea, 1 placebo, and none from malaria). Hydroxyurea treatment appears safe for children with SCA living in malaria-endemic sub-Saharan Africa, without increased severe malaria, infections, or AEs. Hydroxyurea provides SCA-related laboratory and clinical efficacy, but optimal dosing and monitoring regimens for Africa remain undefined. This trial was registered at www.clinicaltrials.gov as #NCT01976416.


Journal of Nutrition | 2016

Delaying Iron Therapy until 28 Days after Antimalarial Treatment Is Associated with Greater Iron Incorporation and Equivalent Hematologic Recovery after 56 Days in Children: A Randomized Controlled Trial

Sarah E. Cusick; Robert O. Opoka; Steven A. Abrams; Chandy C. John; Michael K. Georgieff; Ezekiel Mupere

BACKGROUND Iron therapy begun concurrently with antimalarial treatment may not be well absorbed because of malaria-induced inflammation. Delaying the start of iron therapy may permit better iron absorption and distribution. OBJECTIVE We compared erythrocyte iron incorporation in children who started iron supplementation concurrently with antimalarial treatment or 28 d later. We hypothesized that delayed iron supplementation would be associated with greater incorporation and better hematologic recovery. METHODS We enrolled 100 children aged 6-59 mo with malaria and hemoglobin concentrations of 50.0-99.9 g/L who presented to Mulago Hospital, Kampala, into a randomized trial of iron therapy. All children were administered antimalarial treatment. Children with zinc protoporphyrin (ZPP) ≥80 μmol/mol heme were randomly assigned to start iron supplementation concurrently with the antimalarial treatment [immediate iron (I) group] or 28 d later [delayed iron (D) group]. All children were administered iron-stable isotope (57)Fe on day 0 and (58)Fe on day 28. We compared the percentage of iron incorporation at the start of supplementation (I group at day 0 compared with D group at day 28, aim 1) and hematologic recovery at day 56 (aim 2). RESULTS The percentage of iron incorporation (mean ± SE) was greater at day 28 in the D group (16.5% ± 1.7%) than at day 0 in the I group (7.9% ± 0.5%; P < 0.001). On day 56, concentrations of hemoglobin and ZPP and plasma ferritin, soluble transferrin receptor (sTfR), hepcidin, and C-reactive protein did not differ between the groups. On day 28, the hemoglobin (mean ± SD) and plasma iron markers (geometric mean; 95% CI) reflected poorer iron status in the D group than in the I group at this intervening time as follows: hemoglobin (105 ± 15.9 compared with 112 ± 12.4 g/L; P = 0.04), ferritin (39.3 μg/L; 23.5, 65.7 μg/L compared with 79.9 μg/L; 58.3, 110 μg/L; P = 0.02), sTfR (8.9 mg/L; 7.4, 10.7 mg/L compared with 6.7 mg/L; 6.1, 7.5 mg/L; P = 0.01), and hepcidin (13.3 ng/mL; 8.3, 21.2 ng/mL compared with 38.8 ng/mL; 28.3, 53.3 ng/mL; P < 0.001). CONCLUSIONS Delaying the start of iron improves incorporation but leads to equivalent hematologic recovery at day 56 in Ugandan children with malaria and anemia. These results do not demonstrate a clear, short-term benefit of delaying iron. This trial was registered at clinicaltrials.gov as NCT01754701.


Pediatrics | 2017

Neurodevelopment: The impact of nutrition and inflammation during early to middle childhood in low-resource settings

Chandy C. John; Maureen M. Black; Charles A. Nelson

The early to middle childhood years are a critical period for child neurodevelopment. Nutritional deficiencies, infection, and inflammation are major contributors to impaired child neurodevelopment in these years, particularly in low-resource settings. This review identifies global research priorities relating to nutrition, infection, and inflammation in early to middle childhood neurodevelopment. The research priority areas identified include: (1) assessment of how nutrition, infection, or inflammation in the preconception, prenatal, and infancy periods (or interventions in these periods) affect function in early to middle childhood; (2) assessment of whether effects of nutritional interventions vary by poverty or inflammation; (3) determination of the feasibility of preschool- and school-based integrated nutritional interventions; (4) improved assessment of the epidemiology of infection- and inflammation-related neurodevelopmental impairment (NDI); (5) identification of mechanisms through which infection causes NDI; (6) identification of noninfectious causes of inflammation-related NDI and interventions for causes already identified (eg, environmental factors); and (7) studies on the effects of interactions between nutritional, infectious, and inflammatory factors on neurodevelopment in early to middle childhood. Areas of emerging importance that require additional study include the effects of maternal Zika virus infection, childhood environmental enteropathy, and alterations in the child’s microbiome on neurodevelopment in early to middle childhood. Research in these key areas will be critical to the development of interventions to optimize the neurodevelopmental potential of children worldwide in the early to middle childhood years.


Open Forum Infectious Diseases | 2016

Host Biomarkers Are Associated With Response to Therapy and Long-Term Mortality in Pediatric Severe Malaria

Andrea L. Conroy; Michael Hawkes; Chloe R. McDonald; Hani Kim; Sarah J. Higgins; Kevin R. Barker; Sophie Namasopo; Robert O. Opoka; Chandy C. John; W. Conrad Liles; Kevin C. Kain

Background. Host responses to infection are critical determinants of disease severity and clinical outcome. The development of tools to risk stratify children with malaria is needed to identify children most likely to benefit from targeted interventions. Methods. This study investigated the kinetics of candidate biomarkers of mortality associated with endothelial activation and dysfunction (angiopoietin-2 [Ang-2], soluble FMS-like tyrosine kinase-1 [sFlt-1], and soluble intercellular adhesion molecule-1 [sICAM-1]) and inflammation (10 kDa interferon γ-induced protein [CXCL10/IP-10] and soluble triggering receptor expressed on myeloid cells-1 [sTREM-1]) in the context of a randomized, double-blind, placebo-controlled, parallel-arm trial evaluating inhaled nitric oxide versus placebo as adjunctive therapy to parenteral artesunate for severe malaria. One hundred eighty children aged 1–10 years were enrolled at Jinja Regional Referral Hospital in Uganda and followed for up to 6 months. Results. There were no differences between the 2 study arms in the rate of biomarker recovery. Median levels of Ang-2, CXCL10, and sFlt-1 were higher at admission in children who died in-hospital (n = 15 of 180; P < .001, P = .027, and P = .004, respectively). Elevated levels of Ang-2, sTREM-1, CXCL10, and sICAM-1 were associated with prolonged clinical recovery times in survivors. The Ang-2 levels were also associated with postdischarge mortality (P < .0001). No biomarkers were associated with neurodisability. Conclusions. Persistent endothelial activation and dysfunction predict survival in children admitted with severe malaria.


Pediatrics | 2016

Long-term Behavioral Problems in Children With Severe Malaria

John Mbaziira Ssenkusu; James S. Hodges; Robert O. Opoka; Richard Idro; Elsa Shapiro; Chandy C. John; Paul Bangirana

BACKGROUND: Severe malaria in children is associated with long-term neurocognitive impairment, but it is unclear whether it is associated with long-term behavioral problems. METHODS: Children <5 years old with cerebral malaria (CM) or severe malarial anemia (SMA) treated at Mulago Hospital, Kampala, Uganda were assessed for behavioral outcomes at 0, 6, 12, and 24 months using the Child Behavior Checklist. Sample sizes at 0, 12, and 24 months were 122, 100, and 80 in the CM group, 130, 98, and 81 in the SMA group, and 149, 123, and 90 in healthy community control (CC) children, respectively. Age adjusted z-scores for behavioral outcomes were computed using scores for the CC group. Study groups were compared using regression models adjusted for age, nutritional status, preschool education, and socioeconomic status. RESULTS: At 12 months, children with SMA had higher z-scores than CC children for internalizing (mean difference, 0.49; SE, 0.14; P = .001), externalizing (mean difference, 0.49; SE, 0.15; P = .001), and total problems (mean difference, 0.51; SE, 0.15; P < .001). Children with CM had higher adjusted z-scores than CC children for externalizing problems (mean difference, 0.39; SE, 0.15; P = .009) but not internalizing or total problems. At 24 months, children with CM or SMA both had increased internalizing and externalizing behavioral problems compared with CC children (P ≤ .05 for all). CONCLUSIONS: CM and SMA are associated with long-term internalizing and externalizing behavioral problems in children. They may contribute substantially to mental health morbidity in children <5 years old in malaria endemic areas.


PLOS ONE | 2017

Delaying the start of iron until 28 days after antimalarial treatment is associated with lower incidence of subsequent illness in children with malaria and iron deficiency

Ericka G. Jaramillo; Ezekiel Mupere; Robert O. Opoka; James S. Hodges; Troy C. Lund; Michael K. Georgieff; Chandy C. John; Sarah E. Cusick

We evaluated the incidence of all-cause and malaria-specific clinic visits during follow-up of a recent trial of iron therapy. In the main trial, Ugandan children 6–59 months with smear-confirmed malaria and iron deficiency [zinc protoporphyrin (ZPP > = 80 μmol/mol heme)] were treated for malaria and randomized to start a 27-day course of oral iron concurrently with (immediate group) or 28 days after (delayed group) antimalarial treatment. All children were followed for the same 56-day period starting at the time of antimalarial treatment (Day 0) and underwent passive and active surveillance for malaria and other morbidity for the entire follow-up period. All ill children were examined and treated by the study physician. In this secondary analysis of morbidity data from the main trial, we report that although the incidence of malaria-specific visits did not differ between the groups, children in the immediate group had a higher incidence rate ratio of all-cause sick-child visits to the clinic during the follow-up period (Incidence Rate Ratio (IRR) immediate/delayed = 1.76; 95%CI: 1.05–3.03, p = 0.033). Although these findings need to be tested in a larger trial powered for malaria-specific morbidity, these preliminary results suggest that delaying iron by 28 days in children with coexisting malaria and iron deficiency is associated with a reduced risk of subsequent all-cause illness.


BMC Medicine | 2016

Primaquine plus artemisinin combination therapy for reduction of malaria transmission: promise and risk

Chandy C. John

Reduction of gametocyte transmission from humans to mosquitoes is a key component of malaria elimination. The study by Gonçalves and colleagues provides valuable new data on how the addition of low-dose primaquine to artemether-lumefantrine affects reduction of gametocytemia and transmission of gametocytes to mosquitoes in asymptomatically Plasmodium falciparum-infected children without G6PD deficiency, and on the degree to which low-dose primaquine affects hemoglobin levels in these children. The study sets the stage for future research required for consideration of an artemisinin combination therapy (ACT)-primaquine regimen in mass drug administration campaigns. Future studies will need to evaluate toxicity in adults and G6PD deficient persons, assess gametocyte transmission from adults, evaluate different ACT drugs with primaquine, and assess the implications of “rare” toxicities in large treatment populations, such as hemolysis requiring blood transfusion. The study highlights both the promise and the potential risk of ACT-primaquine treatment in malaria elimination campaigns.Please see related article: https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-016-0581-y.

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