Splenic function is not maintained long-term after partial splenectomy in children with sickle cell disease.

BACKGROUND: Partial splenectomy (PS) may allow preservation of splenic function in cases where splenectomy is indicated for hematologic diseases; however, the long-term outcomes are uncertain. We investigated the long-term outcomes of PS in patients with sickle cell disease (SCD). METHODS: A single-institution retrospective chart review was performed for children with SCD who underwent PS from 1997 to 2017. For comparison, we reviewed outcomes for patients who underwent PS for hereditary spherocytosis (HS). The primary endpoint was viability of the splenic remnant as inferred by the presence of remnant perfusion on ultrasound and/or liver spleen scan. RESULTS: Nine patients with SCD and 26 patients with HS underwent PS at a median age of 11 (IQR, 9-14) and 7.5 (IQR, 6-13) years, respectively. All underwent laparoscopic PS with three (7.9%) conversions to open. Two SCD patients were lost to long-term follow-up. The remaining seven SCD patients had initial postoperative splenic remnant perfusion demonstrated by ultrasonography. By 42 months postoperatively, however, none had a functioning splenic remnant. The median time to loss of splenic remnant was 12.6 (IQR 9.2-28.5) months. In contrast, all HS patients demonstrated robust splenic remnant blood flow with a median follow-up of 46 (IQR 37-82) months. CONCLUSION: No patient with SCD who underwent PS had viable splenic tissue for more than 42 months, likely due to continued autoinfarction typical of patients with this disease. Therefore, we believe that PS to preserve splenic function is not indicated in patients with SCD. LEVEL OF EVIDENCE: III.

A Quality Improvement Intervention to Decrease Postoperative Opioid Prescriptions in Pediatric Oncology Patients.

PURPOSE: This quality improvement initiative aimed to minimize opioid prescribing after oncologic pediatric surgery. METHODS: Retrospective surgical data collected at a pediatric cancer hospital from July 2016 to June 2018 included hospitalization details, oral morphine equivalents prescribed, unplanned visits/calls because of pain, and parental/patient satisfaction with pain control. The quality improvement initiative promoted opioid prescription at discharge on the basis of prior inpatient requirements and education regarding nonopioid analgesia. Upon commencing this project in July 2018, we collected data prospectively. RESULTS: The retrospective and the prospective cohorts included 271 and 99 patients, respectively. Mean (SD) oral morphine equivalents (mg/kg) prescribed upon discharge was significantly reduced in the prospective (0.75±1.34) versus retrospective cohorts (5.48±6.94, P<0.001). The unplanned visits/calls regarding pain were 23 (retrospective, 8.5%) and 2 (prospective, 2.0%). In total, 44 patients (44.4%) received an opioid prescription at discharge in the prospective cohort, significantly fewer than retrospective cohort (251, 92.6%, P<0.001), and used a mean of 34.3 of 159.8 (21.5%) doses dispensed. Length of stay was comparable (P=0.88) between cohorts. Prospective satisfaction rate was 96.2%, leaving 3 patients (3.8%) not satisfied with their pain control regimen. CONCLUSIONS: Dramatic reduction of opioid prescriptions after oncologic surgery can be achieved without detriment to patient satisfaction or readmissions. LEVEL OF EVIDENCE: Level V.

Neutropenia at the time of subcutaneous port insertion may not be a risk factor for early infectious complications in pediatric oncology patients.

BACKGROUND: The risk of infection associated with subcutaneous port (SQP) placement in patients with neutropenia remains unclear. We reviewed the rate of early infectious complications (<30 days) following SQP placement in pediatric oncology patients with or without neutropenia [absolute neutrophil count (ANC) <500/mm3]. METHODS: Baseline characteristics and infectious complications were compared between groups using univariate and multivariate analyses. RESULTS: A total of 614 SQP were placed in 542 patients. Compared to nonneutropenic patients, those with neutropenia were more likely to have leukemia (n = 74, 94% vs n = 268, 50%), preoperative fever (n = 17, 22% vs n = 25, 5%), recent documented infection (n = 15, 19% vs n = 47, 9%), and were younger (81 vs 109 months) (p values <0.01). After adjusting for fever and underlying-disease, there was a nonsignificant association between neutropenia and early postoperative infection (OR 2.42, 95% CI 0.82-7.18, p = 0.11). Only preoperative fever was a predictor of infection (OR 6.09, 95% CI 2.08-17.81, p = 0.001). CONCLUSION: SQP placement appears safe in most neutropenic patients. TYPE OF STUDY: Retrospective comparative study. LEVEL OF EVIDENCE: Level III.

Overall Survival and Renal Function of Patients With Synchronous Bilateral Wilms Tumor Undergoing Surgery at a Single Institution.

OBJECTIVES: Wilms tumor is the most common renal cancer in children. Approximately 5% of children with Wilms tumor present with disease in both kidneys. The treatment challenge is to achieve a high cure rate while maintaining long-term renal function. We retrospectively reviewed our institutional experience with nephron sparing surgery (NSS) in patients with synchronous bilateral Wilms tumor (BWT) operated on between 2001 and 2014. METHODS: Imaging studies, surgical approach, adjuvant therapy, and pathology reports were reviewed. Outcomes evaluated included surgical complications, tumor recurrence, patient survival, and renal function, as assessed by estimated glomerular filtration rate. RESULTS: A total of 42 patients with BWT were identified: 39 (92.9%) patients underwent bilateral NSS; only 3 patients (7.1%) underwent unilateral nephrectomy with contralateral NSS. Postoperative complications included prolonged urine leak (10), infection (6), intussusception (2), and transient renal insufficiency (1). Three patients required early (within 4 months) repeat of NSS for residual tumor. In the long-term, 7 (16.7%) patients had local tumor recurrence (managed with repeat NSS in 6 and completion nephrectomy in 1) and 3 had an episode of intestinal obstruction requiring surgical intervention. Overall survival was 85.7% (mean follow-up, 4.1 years). Of the 6 patients who died, 5 had diffuse anaplastic histology. All of the patients had an estimated glomerular filtration rate more than 60 mL/min/1.73 m at the last follow-up; no patient developed end-stage renal disease. CONCLUSIONS: In patients with synchronous, BWT, bilateral NSS is safe and almost always feasible, thereby preserving maximal renal parenchyma. With this approach, survival was excellent, as was maintenance of the renal function.

Hydroxycarbamide in very young children with sickle-cell anaemia: a multicentre, randomised, controlled trial (BABY HUG).

BACKGROUND: Sickle-cell anaemia is associated with substantial morbidity from acute complications and organ dysfunction beginning in the first year of life. Hydroxycarbamide substantially reduces episodes of pain and acute chest syndrome, admissions to hospital, and transfusions in adults with sickle-cell anaemia. We assessed the effect of hydroxycarbamide therapy on organ dysfunction and clinical complications, and examined laboratory findings and toxic effects. METHODS: This randomised trial was undertaken in 13 centres in the USA between October, 2003, and September, 2009. Eligible participants had haemoglobin SS (HbSS) or haemoglobin Sß(0)thalassaemia, were aged 9-18 months at randomisation, and were not selected for clinical severity. Participants received liquid hydroxycarbamide, 20 mg/kg per day, or placebo for 2 years. Randomisation assignments were generated by the medical coordinating centre by a pre-decided schedule. Identical appearing and tasting formulations were used for hydroxycarbamide and placebo. Patients, caregivers, and coordinating centre staff were masked to treatment allocation. Primary study endpoints were splenic function (qualitative uptake on (99)Tc spleen scan) and renal function (glomerular filtration rate by (99m)Tc-DTPA clearance). Additional assessments included blood counts, fetal haemoglobin concentration, chemistry profiles, spleen function biomarkers, urine osmolality, neurodevelopment, transcranial Doppler ultrasonography, growth, and mutagenicity. Study visits occurred every 2-4 weeks. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00006400. FINDINGS: 96 patients received hydroxycarbamide and 97 placebo, of whom 83 patients in the hydroxycarbamide group and 84 in the placebo group completed the study. Significant differences were not seen between groups for the primary endpoints (19 of 70 patients with decreased spleen function at exit in the hydroxycarbamide group vs 28 of 74 patients in the placebo group, p=0·21; and a difference in the mean increase in DTPA glomerular filtration rate in the hydroxycarbamide group versus the placebo group of 2 mL/min per 1·73 m(2), p=0·84). Hydroxycarbamide significantly decreased pain (177 events in 62 patients vs 375 events in 75 patients in the placebo group, p=0·002) and dactylitis (24 events in 14 patients vs 123 events in 42 patients in the placebo group, p<0·0001), with some evidence for decreased acute chest syndrome, hospitalisation rates, and transfusion. Hydroxyurea increased haemoglobin and fetal haemoglobin, and decreased white blood-cell count. Toxicity was limited to mild-to-moderate neutropenia. INTERPRETATION: On the basis of the safety and efficacy data from this trial, hydroxycarbamide can now be considered for all very young children with sickle-cell anaemia. FUNDING: The US National Heart, Lung, and Blood Institute; and the National Institute of Child Health and Human Development.

The effects of hydroxycarbamide and magnesium on haemoglobin SC disease: results of the multi-centre CHAMPS trial.

In a phase-II multi-centre double-blinded trial, we evaluated haematological effects of oral hydroxycarbamide (HC) and magnesium (Mg) in patients with HbSC, aged 5-53 years old. Subjects were randomized to HC + placebo, Mg + placebo, HC + Mg, or placebo + placebo. The primary endpoint was the proportion of hyperdense red blood cells after 8 weeks. Thirty-six subjects were evaluable, but the study was terminated early because of slow enrollment. In the combined HC groups, mean cell volume and HbF were increased, but differences were not seen in hyperdense red cells or vaso-occlusive events. Mg had no effects. Further investigation of hydroxycarbamide as monotherapy in HbSC disease is warranted.

Recruitment of infants with sickle cell anemia to a Phase III trial: data from the BABY HUG study.

BACKGROUND: Protocol-eligible subjects may not be candidates for research participation or may decline. To determine factors that affected accrual, we evaluated enrollment in BABY HUG, a multi-center, randomized, placebo-controlled Phase III trial of hydroxyurea (HU) in infants with sickle cell anemia. METHODS: An anonymized registry of potential subjects served as the primary source of data. Study coordinators considered all infants less than age 18 months with a hemoglobin FS diagnosis on newborn screening. Data included the number of potentially eligible subjects, whether parents were approached, and reasons for participating or declining. RESULTS: Of 1106 potential participants, 28% were not approached for reasons such as prior poor adherence to clinical care. Interested families expressed willingness to contribute to medical knowledge (51%), hope of being randomized to receive hydroxyurea (51%), and desire for closer clinical care (51%) as reasons for participating. Disease severity or the perception that their child was ill had less impact on willingness to participate (16%). Parents who declined cited fear of research (19%), transportation problems (14%), and the demanding nature of the study (25%). Ultimately, 234 (21%) gave informed consent, with little variability of acceptance rates among sites. Importantly, the number of subjects enrolled correlated with the number of families that were approached. Sites that excluded patients based on clinical/psychosocial biases were not more successful in recruiting than those who approached all eligible subjects. CONCLUSION: Large, demanding clinical trials require an adequate pool of potential participants. Approaching all potentially eligible patients without predetermined biases enhances success in recruitment.

Phase I study of magnesium pidolate in combination with hydroxycarbamide for children with sickle cell anaemia.

In sickle cell anaemia, red cell dehydration increases intracellular HbS concentration and promotes sickling. Higher erythrocyte magnesium reduces water loss through negative regulation of membrane transporters. Hydroxycarbamide (also known as hydroxyurea) reduces sickling partly by increasing intracellular HbF. Combining drugs with distinct mechanisms could offer additive effects. A phase I trial combining oral magnesium pidolate and hydroxycarbamide was performed to estimate the maximum tolerated dose (MTD) and toxicity of magnesium. Cohorts of three children with HbSS, who were on a stable dose of hydroxycarbamide (median 28.5 mg/kg/d), received magnesium pidolate for 6 months beginning at 83 mg/kg/d. The dose was escalated by 50% for subsequent cohorts. Laboratory evaluations were performed at 0, 3, 6 and 9 months. Sixteen children (aged 4-12 years) participated. All four dose-limiting toxicities (grade III diarrhoea and abdominal pain) occurred within the first month of starting magnesium. Additionally, diarrhoea grades I (n = 1) and II (n = 3), and abdominal pain grade II (n = 3) occurred. Hydroxycarbamide dose reduction or interruption was not required. The MTD for magnesium pidolate used in combination with hydroxycarbamide was 125 mg/kg/d. KCl co-transporter activity declined after 3 months of magnesium pidolate (P = 0.02). A phase II study is needed to investigate the efficacy of this drug combination.

Long-term hydroxyurea therapy for infants with sickle cell anemia: the HUSOFT extension study.

The long-term efficacy and toxicity of hydroxyurea for infants are undefined, and its role in preventing organ dysfunction is unknown. Short-term feasibility of hydroxyurea administration, toxicities, hematologic effects, and effect on spleen function in infants with sickle cell anemia (SCA) were reported (Hydroxyurea Safety and Organ Toxicity [HUSOFT] trial). These infants completing 2 years of hydroxyurea therapy (20 mg/kg/d) were offered study extension with dose escalation to 30 mg/kg/d. Patients were monitored with laboratory tests and biannual imaging studies. Hematologic indices were compared with predicted age-specific values and event rates compared with historic rates. All 21 subjects completing the original trial enrolled in the extension study: median age, 3.4 years old (range, 2.6 to 4.4 years); 12 females; 20 with Hb SS, 1 with Hb S/beta0-thalassemia. Seventeen patients completed 4 years of hydroxyurea, and 11 completed 6 years. After 4 years, hydroxyurea was associated with increased hemoglobin concentration, percentage of fetal hemoglobin (Hb F), and mean corpuscular volume (MCV) and decreased reticulocytes, white blood cells (WBCs), and platelets (P < .01). Patients experienced 7.5 acute chest syndrome (ACS) events per 100 person-years, compared with 24.5 events per 100 person-years among historic controls (P = .001). Treated patients had better spleen function than expected and improved growth rates. Infants with SCA tolerate prolonged hydroxyurea therapy with sustained hematologic benefits, fewer ACS events, improved growth, and possibly preserved organ function.

Brain imaging findings in pediatric patients with sickle cell disease.

PURPOSE: To determine prevalence of imaging abnormalities in the brain of children with sickle cell disease (SCD) and to identify clinical and methodological factors that influence prevalence estimate. MATERIALS AND METHODS: Magnetic resonance (MR) imaging and MR angiographic findings for 185 patients with SCD examined at St Jude Children's Research Hospital since 1993 were reviewed. At least two readers independently reviewed images. Standard MR imaging criteria were used to identify lacunae, loss of white matter volume, encephalomalacia, or leukoencephalopathy. Patients were assigned grades to indicate limited or extensive abnormalities. Standard MR angiographic criteria were used to identify arterial tortuosity (limited vasculopathy) and stenosis or occlusion (extensive vasculopathy). Findings were evaluated as a function of patient clinical status (including stroke) and diagnosis. Recent methods (T1- and T2-weighted MR imaging plus fluid-attenuated inversion recovery [FLAIR] at 3-mm section thickness) were compared with older methods (T1- and T2-weighted MR imaging without FLAIR at 5-mm section thickness). RESULTS: At mean age of 10 years, overall prevalence of infarction, ischemia, or atrophy in patients with SCD was 44% (82 of 185), and prevalence of vasculopathy was 55% (102 of 185), without evidence of a significant referral bias. Twenty-six of 27 patients with clinical stroke had abnormal findings at imaging, but even if patients with stroke were excluded, 35% (56 of 158) had a "silent infarction" (MR imaging-visible injury without clinical stroke), and 49% (78 of 158) had abnormal findings at MR angiography. Patients with clinically severe disease had more abnormalities at MR imaging (P <.001) and MR angiography (P <.004) than did patients with milder disease. Severe vasculopathy was more prevalent in patients with hemoglobin SS than in those with hemoglobin SC (P <.001). Recent imaging methods showed more abnormalities than did older methods (P <.01). With newer methods, 43% (29 of 67) of patients had extensive abnormalities, whereas with older methods, 28% (33 of 116) had extensive abnormalities. CONCLUSION: Prevalence of ischemic brain injury in pediatric patients with SCD is substantially higher than was previously reported, in part because of improvements in imaging methods.

The effect of hydroxyurea on vasculopathy in a child with sickle cell disease.

We report serial CNS findings in a girl with sickle cell disease and stroke. Religious considerations precluded transfusion and bone marrow transplantation; therefore, she received single-agent hydroxyurea therapy for almost 6 years. MR angiography showed that vascular patency improved, although diffuse cerebral atrophy slowly worsened. Hydroxyurea can be effective in treating vasculopathy, but it might not prevent the progression of parenchymal damage in advanced disease.

Hydroxyurea therapy associated with declining serum levels of magnesium in children with sickle cell anemia.

OBJECTIVE: To obtain quantitative serum levels of total and ionized magnesium (Mg(2+)) in children with homozygous sickle cell anemia (SCA) undergoing therapy with hydroxyurea. STUDY DESIGN: Five children, ages 11 to 14 years with homozygous SCA, were enrolled in a dose-escalating trial of hydroxyurea over an 18-month period. Serum levels of total and ionized magnesium together with ionized K(+), Na(+), and Ca(2+) were measured before hydroxyurea and every 6 months during hydroxyurea therapy. RESULTS: Before treatment, 4 of the 5 patients had low or below-normal serum concentrations of Mg(2+) (normal range, 0.51-0.67 mmol/L). All 5 became Mg(2+)-deficient during hydroxyurea therapy, with no indication of recovery until after 12 to 18 months of drug administration (P <.05). Similar changes were noted for total magnesium concentrations. Mean serum levels of K(+), Na(+), and Ca(2+) remained consistently within normal ranges. CONCLUSIONS: These findings warrant a controlled study of the effects of magnesium supplementation in patients with SCA receiving hydroxyurea. Potentially, such therapy could alleviate or prevent vaso-occlusive crises.