Search

Objective: The prevalence of asymptomatic catheter-related thrombosis of the upper venous system in children with cancer has not been determined. We evaluated patients with cancer and implantable central venous catheters (ports) for this complication., Study Design: Children with cancer undergoing port removal were eligible for this study. Vessel patency was evaluated by contrast venography. We examined each child for physical stigmata of thrombosis and retrospectively assessed catheter-related mechanical difficulties and infections., Results: Thirty-one ports had been placed in 24 children (aged 20 months to 18 years; median age, 9 years) with diagnoses of leukemia/lymphoma (n = 10), solid tumor (n = 12), and histiocytosis (n = 2). Venography showed abnormalities in 12 of the 24 patients. Physical examination revealed dilated superficial veins on the chest in 3 patients. Venograms showed abnormalities in all 3 children with prominent superficial thoracic veins. Nine of the 21 other patients had clinically occult central venous occlusion., Conclusion: Fifty percent (95% CI, 30% to 70%) of children who had implantable ports removed during or after treatment of cancer exhibited deep venous thrombosis at the site of catheter placement. Future studies should determine the contribution of inherited and other acquired risk factors for thrombosis and assess measures to prevent and/or treat catheter-related thrombosis in this population.

Objectives: We retrospectively characterized children with idiopathic thrombocytopenic purpura (ITP) who had major hemorrhage to determine response to therapy and long-term outcome., Study Design: We reviewed the medical records of 332 children with ITP diagnosed at our center during the last 10 years for occurrence of major hemorrhage, defined as (1) intracranial hemorrhage, (2) epistaxis requiring cautery or nasal packing, (3) gross hematuria, or (4) other bleeding causing a decline in hemoglobin concentration., Results: Of 332 patients with ITP, 58 (17%) had 68 episodes of major hemorrhage; 56 of these episodes were treated with corticosteroids, intravenous immunoglobulin, or both. The platelet count rose to > or =20,000/mm3 within 24 hours after presentation after only 18% of evaluated events, and 28% of patients with major hemorrhage still had a platelet count <20,000/mm3 after 7 days. Twenty-seven of 49 patients available for evaluation had resolution of ITP within 6 months, 21 had chronic ITP, and 1 died of sepsis., Conclusions: We observed that 17% of children with ITP had major hemorrhage. Only a minority of these patients had an immediate rise in platelet count after receiving intravenous immunoglobulin, corticosteroid treatment, or both. Prospective studies of childhood ITP focusing on short-term outcome variables in addition to platelet count should be performed to better define optimal treatment for each affected child.

Objective: The objective of this study was to define the efficacy and complications of implantable venous access devices (IVADs) in children with hemophilia., Study Design: Records were reviewed on all patients with congenital blood coagulation disorders monitored at two children's hospitals in whom one or more central venous catheters had been placed., Results: Since 1989 external and implantable central venous catheters have been inserted to enhance venous access for regular factor concentrate infusion in 45 patients with hemophilia ranging in age from 8 months to 19.5 years (median 7.4 years); 37 patients had factor VIII deficiency and 8 factor IX deficiency. Hemorrhagic complications of catheter placement were infrequent and minor. In the 41 patients having one or more IVADs in place for a median of 31 months, only six episodes of bacteremia occurred in 5 patients during 44,070 days of follow-up. The overall rate of bacteremia complicating IVADs in these patients was 0.14 episodes per 1000 catheter days. Other catheter-related complications were uncommon. Catheters are still in place in 33 patients for a median of 32 months., Conclusion: The low risk of infection and other complications associated with the use of IVADs makes the use of these devices attractive in the treatment of patients with hemophilia who require frequent venous access for factor concentrate infusions.

Objective: To compare laparoscopic and traditional open splenectomy in children with nonmalignant hematologic disorders., Study Design: Retrospective review of 36 consecutive nonrandomized splenectomies (16 laparoscopic and 20 open) performed for hematologic disorders at a single pediatric institution during the past 3 years. The two-sided Mann-Whitney U test for non-parametric variables was used for statistical analysis., Results: An open procedure was performed on 20 patients (mean age, 9.7 years), five of whom had a concomitant cholecystectomy. A laparoscopic splenectomy was performed on 16 children (mean age, 10.3 years), seven of whom had a concomitant cholecystectomy. The mean anesthesia and operative times were longer in the laparoscopic than in the open group (p < 0.001). However, the mean number of hours of postoperative analgesia was less in the laparoscopic group (p < 0.005). Patients who had laparoscopic splenectomy were also discharged home earlier (p < 0.01) and resumed a regular diet sooner. Mean operating room charges were higher in the laparoscopic group (p < 0.001), but total hospitalization costs were not significantly different. Postoperative complication rates were similar. The hematologic response was comparable., Conclusions: laparoscopic splenectomy is feasible and safe in children with hematologic disorders. Although it currently requires more operative time than the open approach, it is superior with regard to duration of postoperative analgesia, duration of hospital stay, and recovery of bowel function.

Objective: To determine the frequency and severity of acute splenic complications in children and adolescents with sickle cell (SC) hemoglobin C disease., Methods: The medical records of 271 patients with SC disease seen at our center were reviewed to evaluate the incidence and severity of acute complications involving the spleen., Results: Sixteen (6%) children had acute splenic complications. Thirteen (5%) had 16 episodes of acute splenic sequestration (ASSC), with the initial event occurring at a mean age of 8.9 years (range, 2 to 17 years). Splenomegaly had been noted before the initial event in 6 (46%) of the 13 cases, and 3 (23%) had a history of painful splenic infarction. Two young children (aged 4 and 6 years) had a hemoglobin value less than 2 gm/dl, one without history of splenic enlargement. Three (23%) children had a second episode of ASSC. Three additional patients had a history of acute painful splenic infarction, two of whom also had splenic hemorrhage. Eight (3%) of the 271 children required splenectomy (1 after the initial episode of ASSC, 3 after a second episode of ASSC, 2 as a result of pain accompanying chronic infarction and ASSC, and 2 because of splenic hemorrhage). No deaths resulted from ASSC., Conclusions: We conclude that (1) acute splenic complications in children and adolescents with SC disease are relatively uncommon, (2) most episodes of ASSC occur in preadolescents, (3) ASSC can be life threatening, even in younger children, and (4) prior splenomegaly is not a good predictor of ASSC. Thus it is vital that the parents of all children with SC disease be instructed to palpate their child's spleen regularly.

Objectives: (1) To determine serotype-specific IgG antibody responses to reimmunization with pneumococcal polysaccharide vaccine at age 5 years in children with sickle cell anemia and (2) to determine whether continued penicillin prophylaxis had any adverse effects on these responses., Study Design: Children with sickle cell anemia, who had been treated with prophylactic penicillin for at least 2 years before their fifth birthday, were randomly selected at age 5 years to continue penicillin prophylaxis or to receive placebo treatment. These children had been immunized once or twice in early childhood with pneumococcal polysaccharide vaccine and were reimmunized at the time of randomization., Results: Serotype-specific IgG antibody responses to reimmunization varied according to pneumococcal serotype but in general were mediocre or poor; the poorest response was to serotype 6B. The antibody responses were similar in subjects with continued penicillin prophylaxis or placebo treatment, and in subjects who received one or two pneumococcal vaccinations before reimmunization. The occurrence of pneumococcal bacteremia was associated with low IgG antibody concentrations to the infecting serotype., Conclusions: Reimmunization of children with sickle cell anemia who received pneumococcal polysaccharide vaccine at age 5 years induces limited production of serotype-specific IgG antibodies, regardless of previous pneumococcal vaccine history. Continued penicillin prophylaxis does not interfere with serotype-specific IgG antibody responses to reimmunization.

Objectives: To prospectively define the lowest possible doses of recombinant human granulocyte colony-stimulating factor (rhG-CSF) that would benefit selected children with chronic idiopathic neutropenia whose disease was severe enough to interfere appreciably with quality of life., Study Design: The efficacy of low-dose rhG-CSF therapy was investigated in six children with symptomatic chronic idiopathic neutropenia. All patients received rhG-CSF, 5 micrograms/kg subcutaneously, as a single daily dose until an absolute neutrophil count (ANC) above 1.5 x 10(9)/L was observed. The rhG-CSF dosage interval and amount were then increased and decreased, respectively, in an alternating fashion until the lowest rhG-CSF dose that would maintain the ANC above 1.0 x 10(9)/L (1000/mm3) was reached., Results: Although the minimal dose requirements varied, all patients were able to maintain a mean ANC > 1.0 x 10(9)/L during a mean follow-up period of 14 months at doses ranging from 1.0 microgram/kg once weekly to 5.0 micrograms/kg every other day. Administration of rhG-CSF resulted in resolution of all preexisting chronic infections, reduction in the frequency of new infectious episodes, and discontinuation of prophylactic antibiotics. In all patients the ANC decreased to pretreatment values when further reduction or discontinuation of rhG-CSF therapy was attempted. By identifying the minimal effective dose in each patient, we were able to reduce the treatment cost by a mean of 81% compared with daily dosage at 5 micrograms/kg., Conclusions: Recombinant human granulocyte colony-stimulating factor therapy at low doses (< or = 5 micrograms/kg) every 2 to 7 days to symptomatic children with chronic idiopathic neutropenia is effective and no more costly than supportive treatment with antibiotics.

Objective: Despite penicillin prophylaxis and vaccination, infection with encapsulated organisms remains a leading cause of morbidity and death in children with sickle cell disease. The role of Fc receptors in the clearance of encapsulated organisms is well documented. The His(H)-Arg(R) polymorphism at amino acid 131 of the Fc gamma RIIA receptor alters binding affinity for human IgG2 and influences infection with encapsulated organisms in children without sickle cell disease. We hypothesized that the genotype for high-affinity human IgG2 binding (H/H131) is underrepresented in children with sickle cell disease who had encapsulated organism infection., Design: We studied 60 black children with sickle cell disease from four participating centers who had a history of encapsulated organism infection. Genomic DNA from peripheral blood was subjected to amplification by polymerase chain reaction and to sequence analysis for identification of the Fc gamma RIIA genotype, and the genotype distribution was then compared with our data from ethnically matched control subjects., Results: Contrary to our hypothesis, the H/H131 genotype was overrepresented in all individuals (p = 0.046) and in particular in the 11 individuals with a history of Haemophilus influenzae type b infection (64% H/H131, 27% H/R131, 9% R/R131; p = 0.002), in comparison with ethnically matched control subjects (14% H/H131, 60% H/R131, 26% R/R131). In the 51 individuals with a history of Streptococcus pneumoniae infection, the genotype distribution was not statistically significantly different from that of the control population., Conclusions: The H/H131 Fc gamma RIIA genotype is overrepresented in black children with sickle cell disease and a history of H. influenzae type b infection but not in those with S. pneumoniae infection.

Febrile neutropenic children with cancer were eligible for outpatient management with intravenous ceftriaxone therapy if they displayed selected low-risk criteria. Nineteen children were enrolled. All patients had sterile blood cultures, and only one of them was hospitalized because of persistent fever. This pilot study suggests that selected children with febrile neutropenia might be successfully managed without hospitalization.

Objective: To evaluate the consequences of discontinuing penicillin prophylaxis at 5 years of age in children with sickle cell anemia who had received prophylactic penicillin for much of their lives., Design: Randomized, double-blind, placebo-controlled trial., Setting: Eighteen teaching hospitals throughout the United States., Patients: Children with sickle cell anemia (hemoglobin SS or hemoglobin S beta 0-thalassemia) who had received prophylactic penicillin therapy for at least 2 years immediately before their fifth birthday and had received the 23-valent pneumococcal vaccine between 2 and 3 years of age and again at the time of randomization. Of 599 potential candidates, 400 were randomly selected and followed for an average of 3.2 years., Interventions: After randomization, patients received the study medication twice daily--either penicillin V potassium, 250 mg, or an identical placebo tablet. Patients were either seen in the clinic or contacted every 3 months thereafter for an interval history and dispensing of the study drug. A physical examination was scheduled every 6 months., Main Outcome Measures: The primary end point was a comparison of the incidence of bacteremia or meningitis caused by Streptococcus pneumoniae in children continuing penicillin prophylaxis versus those receiving the placebo., Results: Six children had a systemic infection caused by S. pneumoniae, four in the placebo group (2.0%; 95% confidence interval 0.5%, 5.0%) and two in the continued penicillin prophylaxis group (1.0%; 95% confidence interval 0.1%, 3.6%) with a relative risk of 0.5 (95% confidence interval 0.1, 2.7). All invasive isolates were either serotype 6(A or B) or serotype 23F. Four of the isolates were penicillin susceptible, and two (one from each treatment group) were penicillin and multiply antibiotic resistant. Adverse effects of the study drug were reported for three patients (nausea, vomiting, or both), one of whom was in the placebo group., Conclusion: Children with sickle cell anemia who have not had a prior severe pneumococcal infection or a splenectomy and are receiving comprehensive care may safely stop prophylactic penicillin therapy at 5 years of age. Parents must be aggressively counseled to seek medical attention for all febrile events in children with sickle cell anemia.

Objectives: To assess the efficacy and toxicity of very high doses of glucocorticoids in patients with congenital pure red cell aplasia (Diamond-Blackfan anemia) who did not respond to standard doses of prednisone., Study Designs: We prospectively treated eight patients with transfusion-dependent Diamond-Blackfan anemia with high intravenous doses of methylprednisolone. All patients had previously not responded to one or more oral courses of prednisone in standard doses and were dependent on erythrocyte transfusions. Every patient initially received methylprednisolone at a dose of 30 mg/kg per day, followed by slow tapering for 4 weeks, but none responded. All patients then received a second treatment course starting at 100 mg of methylprednisolone per kilogram per day, again followed by slow tapering of the dosage., Results: Three patients had a complete response that has been sustained for 21+, 31+, and 41+ months, respectively. One patient had a partial response. Toxic effects included a rise in serum alanine aminotransferase activity in all patients, transient diabetes mellitus in one child, and three episodes of bacteremia in two patients with intravenous access devices., Conclusions: We conclude that very high doses of methylprednisolone may induce sustained remission in some patients with transfusion-dependent Diamond-Blackfan anemia refractory to standard-dose prednisone therapy.

Objective: To characterize the incidence of bacteremia and its potential for progression to septicemia in children with sickle hemoglobin C disease and sickle beta(+)-thalassemia to assess the need for penicillin prophylaxis., Study Design: Retrospective chart review of the frequency and natural history of bloodstream infection in such patients not receiving prophylactic penicillin therapy and followed up in a single institution., Results: During more than 842 patient-years of observation in 242 patients with sickle hemoglobin C disease, 15 episodes of bacteremia occurred in nine patients. Septicemia was fatal in one patient. The overall incidence of bacteremia, 1.8 events per 100 patient-years (95% confidence limits: 0.8, 2.8) in patients with sickle hemoglobin C disease, was similar to that in hematologically normal children. One episode of bacteremia occurred in a patient with sickle beta(+)-thalassemia., Conclusions: The incidence of bacteremia is not increased in young patients with sickle hemoglobin C disease and sickle beta(+)-thalassemia. Further, unlike its course in children with sickle cell anemia, it rarely evolves into life-threatening septicemia. This probably results from the maintenance of relatively intact splenic function during infancy and early childhood in patients with sickle hemoglobin C disease and sickle beta(+)-thalassemia. Prophylactic penicillin therapy may not be required in these patients.

A 2-year-old boy with sickle cell anemia had a massive, fatal hemolytic reaction after administration of an intravenous dose of ceftriaxone. Laboratory studies demonstrated the presence of an IgM antibody against ceftriaxone, binding to and destroying the patient's erythrocytes by an immune complex mechanism. This rare complication should be considered in the differential diagnosis when hemoglobinuria develops in a child after administration of ceftriaxone or a similar agent.

We retrospectively examined the medical and autopsy records of seven previously unpublished cases of fatal pneumococcal septicemia in children with hemoglobin SC disease. The earliest death occurred in a 1-year-old child who had congenital heart disease with cyanosis; the other children were aged 3 1/2 to 15 years. Only one child had received pneumococcal vaccine or prophylactic penicillin therapy. All seven children had an acute febrile illness and rapid clinical deterioration despite parenterally administered antibiotic therapy and intensive medical support. Erythrocyte pit counts in two patients were 40.3% and 41.7%, respectively (normal, < or = 3.6%). Autopsy data from five cases showed marked splenic congestion without infarction in five, splenomegaly in four, and bilateral adrenal hemorrhage in three. These cases illustrate that functional asplenia predisposes some children with hemoglobin SC disease to the development of fatal septicemia after the age of 3 years. We conclude that pneumococcal vaccine should be administered to all children with hemoglobin SC disease and that acute febrile illnesses should be investigated promptly for the possibility of septicemia. The routine use of prophylactic penicillin therapy in infants and children with hemoglobin SC disease remains controversial.

We recently encountered a previously healthy 3-year-old girl who had severe bleeding resulting from a severe deficiency of prothrombin. A lupus anticoagulant was identified by several different methods. The patient was successfully treated with glucocorticoids. This rare complication of a lupus anticoagulant should be considered in the differential diagnosis of a previously well child who suddenly has hemorrhage.

We evaluated the timing and pattern of changes in the complete blood cell count that preceded marrow recovery during 107 consecutive episodes of fever and neutropenia in 64 children with cancer. Four measures derived from serial daily measurement of the complete blood cell count were evaluated: total leukocyte count, absolute neutrophil count, absolute phagocyte count, and platelet count. During 70 (65%) of these 107 episodes, patients were discharged with an absolute neutrophil count of fewer than 500 cells/mm3; 24 patients were discharged from the hospital despite an absolute neutrophil count of fewer than 100 cells/mm3. During all but one of these 70 episodes, however, signs of early marrow recovery were present before discharge; sustained increases were observed in these patients' leukocyte, absolute neutrophil, absolute phagocyte, and platelet counts 2 or more days before their discharge in 41%, 49%, 50%, and 39% of cases, respectively. Although they were neutropenic at discharge, most patients had signs of multilineage marrow recovery at that time; 59 of 70 had increases in three of four of the measurements that we studied. None of the 69 patients who had evidence of marrow recovery at discharge had recurrence of fever. We conclude that children with cancer who were hospitalized for fever during periods of neutropenia have increases in the peripheral blood cell count that herald imminent bone marrow recovery, often several days before the absolute neutrophil count recovers to 500 cells/mm3. Our success in discharging such patients before resolution of neutropenia suggests that further controlled trials are needed to evaluate the safety and feasibility of cessation of antibiotic therapy and early discharge from the hospital.

We reviewed the records of all patients with a diagnosis of ALL made at our center during a 13-year period to determine the relationship between bone pain and the hematologic findings at diagnosis of acute lymphoblastic leukemia. Of 296 eligible patients, 179 (60%) had no bone pain (group 1), 65 (22%) had some bone pain (group 2), and 52 (18%) had prominent bone pain that overshadowed other manifestations of the leukemia (group 3). Statistically significant differences were found between the groups for hemoglobin concentration (p less than 0.001), leukocyte count (p = 0.014), absolute neutrophil count (p = 0.002), percentage of circulating blast cells (p = 0.009), and platelet count (p less than 0.001). Children in group 3 had values closer to normal for all these values than those of patients in the other groups. Group 3 patients had symptoms an average of more than 2 weeks longer before diagnosis, and had significantly lower serum uric acid and higher calcium levels than patients in the other groups had. No differences were detected among the groups in age at diagnosis, gender, or survival rate. We conclude that children with acute lymphoblastic leukemia who have prominent bone pain preceding the diagnosis frequently have nearly normal hematologic values and that this feature may contribute to a delay in diagnosis.

An 11-year-old boy was noted to have microcytic anemia, growth retardation, polyclonal hypergammaglobulinemia, and abnormal platelet function. An angiomatous lymphoid hamartoma was removed from the retroperitoneal space. Postoperatively the child exhibited a dramatic growth spurt and complete resolution of the abnormal laboratory measurements. Studies were performed before and after tumor removal to investigate the nature of the associated anemia, growth retardation, and altered hemostasis. There was no evidence of iron deficiency, thalassemia, or an antierythropoietin factor. Prolonged bleeding time and impaired ristocetin-induced platelet aggregation normalized following tumor resection. Serum obtained before surgery inhibited lymphocyte proliferation in mixed lymphocyte culture as well as fibroblast growth in vitro. Detailed study of growth regulatory hormones failed to reveal significant alterations except for significantly reduced somatomedin which normalized after surgery. The factor(s) which inhibit in vitro cellular growth and lower in vivo plasma somatomedin concentration remain unknown.

Three siblings had iron deficiency anemia without evidence of reduced iron intake or gastrointestinal blood loss. They failed to respond to oral iron therapy, and malabsorption of oral medicinal iron was demonstrated in two of the children. All three had a partial but incomplete hematologic response to intramuscular iron dextran treatment. There was no evidence for other well-defined causes of hypochromic microcytic anemia or for a generalized disorder of intestinal absorption. These three patients appear to have a familial disorder characterized by impaired iron absorption and utilization, similar to that observed in the mk/mk mouse.

Polyvalent pneumococcal vaccine and oral penicillin prophylaxis are frequently used in patients with functional or anatomic asplenia to protect them from fulminant Streptococcus pneumoniae sepsis. We studied nasopharyngeal colonization with pneumococci in 34 patients with sickle cell anemia (aged 6 months to 5 years) receiving penicillin prophylaxis and in 63 age- and race-matched comparison patients. Patients with sickle cell anemia had fewer positive initial pneumococcal nasopharyngeal cultures than did the comparison group (14.5% vs 34.4%, P = 0.03) and significantly lower carriage rates during the respiratory illness season of November to March (8.7% vs 40.5%, P = 0.005). Penicillin prophylaxis did not result in emergence of penicillin-resistant pneumococci or in an increased carriage rate of Haemophilus influenzae type b. Our data suggest a mechanism of action for penicillin prophylaxis and provide some evidence for the relative safety of this regimen.

The clinical features of long bone infarction in patients with sickle cell disease have not been well defined, and differentiation of bone infarct from osteomyelitis has accordingly been difficult. We reviewed records from 192 children with sickle hemoglobinopathies and identified 41 episodes of acute long bone infarction in 21 patients. The most commonly affected bones were the humerus (38%), tibia (23%), and femur (19%). The distal segment was more commonly involved. Tenderness and prominent swelling occurred in all cases; other findings included impaired joint motion (68%), local heat (65%), and erythema (145). Fever was usually absent or low grade, and patients did not appear ill. Laboratory studies included negative bacterial cultures in all cases, absence of left shift in WBC count in most, and variable erythrocyte sedimentation rate. Plain roentgenographs were unremarkable. Contrary to previous reports, radionuclide bone and bone marrow scans were not helpful in differentiation of bone infarction from osteomyelitis. Patients received supportive therapy and improved within several days. Long-term sequelae were not evident. The rarity of osteomyelitis in our sickle cell population (five cases in 22 years) precluded direct comparison of most of its clinical features with those of bone infarction. Acute long bone infarction is at least 50 times more common than bacterial osteomyelitis in sickle cell disease.

An infant who received multiple blood transfusions in the neonatal intensive care unit developed a transfusion-associated CMV infection at age 11 weeks and thereafter was noted to have hepatosplenomegaly, mitogen hyporesponsiveness, persistent viruria, an abnormal distribution of T-lymphocyte subpopulations, and poor growth. He has had recurrent opportunistic infections, including Pneumocystis carinii pneumonia. Six donors of blood products received by this infant were investigated; one was found to have chronic lymphadenopathy, weight loss, intermittent diarrhea, lymphopenia, and a profound depression of lymphocytes with a helper/inducer surface phenotype (T4 positive). Family members have an abnormal distribution of T cell subpopulations similar to those reported in asymptomatic homosexuals. The course of disease in our patient suggests that acquired immune deficiency syndrome may be transmitted to young infants via blood products.

Since the approach to the management and outcome of extreme hyperbilirubinemia in patients with sickle cell anemia is not clearly defined, we reviewed our experience with marked hyperbilirubinemia in six children with sickle cell disease. Intrahepatic sickling (sickle hepatopathy) rather than hepatitis or biliary stones appeared primarily responsible for the extreme jaundice in at least four children and possibly in all six. Signs and symptoms were few, and laboratory abnormalities were not striking other than marked hyperbilirubinemia (total serum bilirubin concentrations ranging from 20.4 to 57.6 mg/dl with approximately one half conjugated). All of the children improved within days to weeks and currently are well, without recurrence of hyperbilirubinemia or evidence of chronic liver disease. The patients described here suggest that sickling within the liver, previously reported to be a serious and even fatal syndrome, usually is a benign and self-limited process.

We studied splenic function in children with cancer by quantitation of pitted, or pocked, erythrocytes (pocked RBC count), that is, the percentage of erythrocytes containing one or more membrane-bound vesicles, as determined by phase interference microscopy. The mean pocked RBC count in 93 normal children and adults was 0.49% (range 0% to 2.0%), with only 2.4% of normal subjects having values greater than 1.5%. Mean pocked RBC count in 28 children after splenectomy was 37% (range 3.2% to 81%). Among 181 children with cancer (525 specimens), the mean pocked RBC count was 1.06% (range 0% to 12.6%). Fifty-nine (32%) patients had one or more values greater than 1.5%, and 25 (13.8%) children had measurements greater than 3.0%, a level previously suggested to have clinical significance. Elevated pocked RBC counts (greater than 1.5%) occurred in more than one third of children with Wilms tumor and acute lymphoblastic leukemia, and in both patients with juvenile chronic myelogenous leukemia. Elevations in pocked RBC counts were not related to specific chemotherapy regimens or to disease activity. Mild splenic reticuloendothelial hypofunction occurs in many children with cancer and may contribute to the risk of infection in these patients.

The records of 22 children with the diagnosis of idiopathic immune hemolytic anemia were reviewed. Fifty per cent of the children had a history of an antecedent infection and 32% had underlying immune deficiency or lymphoproliferative diseases. The majority (77%) of the patients had an acute self-limited disease which was frequently associated with a positive complement or nongamma Coombs test. The anemia was usually severe, and a number of the children had reticulocytopenia at the time of diagnosis. These children responded rapidly to transfusions and corticosteroids and generally remained well on follow-up. Immunosuppressive drugs did not prove useful in two patients refractory to prednisone, but splenectomy was apparently beneficial in three of four patients so treated. Mortality rate was 18%, with most of the deaths related to an underlying disease.

To determine the effects of blood transfusions on splenic function in older patients with sickle cell anemia, we investigated splenic function in 12 patients who had had cerebrovascular accidents and who were being treated at two collaborating centers using different transfusion protocols. Splenic function was assessed by radionuclide scan and pocked erythrocyte count. Patients were 6 to 18 years of age and had been receiving transfusions for 7 months to 10 years (median 4.2 years). Of the 12 children, five had normal or increased splenic size and function (normal scan and normal or minimally elevated pocked erythrocyte count). All were receiving intensive transfusion therapy, with the aim of maintaining the hemoglobin S level at less than 20%. The other seven patients had abnormal splenic function (absent radionuclide uptake and elevated pocked erythrocyte count); each was receiving less intensive transfusion therapy, with the pretransfusion hemoglobin S level usually at 30% to 40%. No patient developed bacterial septicemia while receiving hypertransfusion therapy. We conclude that splenic function during a long-term transfusion program is variable, depending in part on the "intensity" of transfusion therapy. Apparent splenic involution and fibrosis may be a reversible event in some patients.