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J S Lobel

Publications and source records attributed to J S Lobel.

16 recordsLinked to original sources
PubMed1990

Aluminum-induced microcytosis in a child with moderate renal insufficiency.

A child with moderate renal failure, on high doses of aluminum compounds for treatment for hyperphosphatasemia, presented with unexplained microcytosis. The patient also had psychomotor delay. On discontinuation of aluminum, microcytosis reversed in 2 months. Four months later, psychomotor development improved. Children with renal failure, on aluminum supplementation, should be carefully monitored for toxicity. Microcytosis may be a clue to aluminum toxicity in such patients.

Aluminum Hydroxide↗
PubMed1989

Parvovirus B19 infection associated with reticulocytopenia and chronic autoimmune hemolytic anemia.

A previously healthy 11-year-old white female presented with a Coomb's positive hemolytic anemia and reticulocytopenia. The patient was treated with prednisone (6.4 mg/kg/day) and had a stable hemoglobin with subsequent recovery of reticulocytes by 7 days. Bone marrow aspiration showed hypercellularity with arrest of red cell maturation. The patient's serum contained specific IgM and IgG antibodies to parvovirus B19. Our report confirms parvovirus B19 as a cause of reticulocytopenia at presentation in autoimmune hemolytic anemia. Immunosuppressive therapy with prednisone did not appear to significantly prolong the course of the B19 infection.

Anemia, Hemolytic, Autoimmune↗
PubMed1989

Value of screening umbilical cord blood for hemoglobinopathy.

Foremost among the beneficial effects of screening umbilical cord blood is the optimized quality of care that can follow the immediate involvement of an infant with sickle cell disease and his or her family in an appropriate health care system. This is exemplified by the reduction in the case fatality rate of pneumococcal septicemia that has been achieved. Appropriate follow-up of screening also includes transmission of information about the diagnosis of a hemoglobinopathy trait or alpha-thalassemia to affected families and their physicians, with ready availability of education and counseling.

Anemia, Sickle Cell↗
PubMed1988

Methemoglobinemia and hemolytic anemia associated with Campylobacter jejuni enteritis.

A 7-week-old infant with methemoglobinemia, hemolytic anemia, and inadequate weight gain was found to have a Campylobacter jejuni gastrointestinal tract infection. Known etiologies of methemoglobinemia such as oxidative drug exposure, deficiency of NADH-methemoglobin reductase, and hemoglobin M disorder were excluded. The patient had a twin brother (probably identical) who had neither methemoglobinemia nor stool cultures positive for C. jejuni. The twin essentially served as an experimental control, making other environmental or genetic causes of methemoglobinemia unlikely in the patient. Both the methemoglobinemia and the C. jejuni infection responded to adequate treatment with erythromycin. The association of a C. jejuni infection with methemoglobinemia is discussed in light of previous associations of enteritis and methemoglobinemia in infants.

Anemia, Hemolytic↗
PubMed1988

Severe anemia caused by human parvovirus in a leukemia patient on maintenance chemotherapy.

A 6-year-old boy on maintenance chemotherapy for acute lymphocytic leukemia developed severe hypoplastic anemia during chemotherapy previously well tolerated. The hypoplastic episode persisted for approximately 30 days. Human parvovirus (B19), the etiologic agent of aplastic crisis in persons with underlying hemolytic syndromes, was detected in the patient's serum 25-30 days after onset of hemoglobin decrease, and B19 IgM seroconversion occurred 1 week later. The patient's hypoplastic anemia was presumably caused by prolonged B19 infection resulting from a blunted immune response. An immune response to the B19 infection and resolution of the illness were temporally associated with brief cessation of chemotherapy.

Anemia, Aplastic↗
PubMed1987

Direct evidence that decreased serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in sickle cell disease is related to antibody deficiency.

Two approaches were used to demonstrate that reduction in serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in children with sickle cell disease is related to a deficiency of antibodies to pneumococcal capsular polysaccharide. First, opsonization of S. pneumoniae mediated by the alternative pathway in patients' sera was restored to normal by addition of the purified IgG or IgM fraction of goat antiserum to capsular polysaccharide of the homologous serotype. Secondly, IgG antibody titers to capsular polysaccharide in patients' sera correlated significantly with alternative pathway-mediated opsonization; the correlation between titers of IgM anticapsular antibodies and opsonization approached statistical significance. The sum of the IgG and IgM anticapsular antibody titers correlated most significantly with opsonization. Our results suggest that reduction in alternative pathway-mediated opsonization in sera from children with sickle cell disease is related to low levels of both IgG and IgM anticapsular antibodies.

Anemia, Sickle Cell↗
PubMed1986

Prophylaxis with oral penicillin in children with sickle cell anemia. A randomized trial.

Children with sickle cell anemia have an increased susceptibility to bacterial infections, especially to those caused by Streptococcus pneumoniae. We therefore conducted a multicenter, randomized, double-blind, placebo-controlled clinical trial to test whether the regular, daily administration of oral penicillin would reduce the incidence of documented septicemia due to S.pneumoniae in children with sickle cell anemia who were under the age of three years at the time of entry. The children were randomly assigned to receive either 125 mg of penicillin V potassium (105 children) or placebo (110 children) twice daily. The trial was terminated 8 months early, after an average of 15 months of follow-up, when an 84 percent reduction in the incidence of infection was observed in the group treated with penicillin, as compared with the group given placebo (13 of 110 patients vs. 2 of 105; P = 0.0025), with no deaths from pneumococcal septicemia occurring in the penicillin group but three deaths from the infection occurring in the placebo group. On the basis of these results, we conclude that children should be screened in the neonatal period for sickle cell hemoglobinopathy and that those with sickle cell anemia should receive prophylactic therapy with oral penicillin by four months of age to decrease the morbidity and mortality associated with pneumococcal septicemia.

Administration, Oral↗
PubMed1986

Lack of a requirement for the Fc region of IgG in restoring pneumococcal opsonization via the alternative complement pathway in sickle cell disease.

Children with sickle cell disease have reduced serum opsonization of Streptococcus pneumoniae. Our previous studies have suggested that opsonization mediated by both the alternative and classic complement pathways is reduced because of a deficiency of IgG antibodies to pneumococcal capsular polysaccharide. This study compares the ability of purified IgG (fractionated from goat antiserum to pneumococcal capsular polysaccharide) and F(ab')2 fragments of the IgG preparation to restore alternative pathway-mediated opsonization of S. pneumoniae to sera from patients with sickle cell disease. Both the whole IgG preparation and F(ab')2 fragments of this preparation restored opsonization to normal levels and concomitantly increased alternative pathway-mediated deposition of C3 onto the pneumococci to a supranormal level. These results suggest that enhancement of opsonization is mediated by the F(ab')2 region of IgG antibody to capsular polysaccharide and is associated with an increase in complement deposition on the bacterial surface.

Adolescent↗
PubMed1985

Relation between serum opsonic activity for Streptococcus pneumoniae and complement function in sickle cell disease.

Opsonic activity for Streptococcus pneumoniae mediated by the alternative and classic complement pathways and concomitant binding of activated C3 to the bacteria were measured in sera from children with sickle cell disease and normal siblings of similar age. Uptake of radiolabeled serotypes 7F, 10A, 15B, and 24F by normal human polymorphonuclear leukocytes and intracellular killing were the parameters used to assess opsonization. C3 fixation was quantitated by radioimmunoassay under conditions identical to those used for opsonic measurements. Both classic and alternative pathway-mediated opsonic activities were significantly reduced in a subset of patients. These alterations were associated with reduction in C3 fixation by way of the classic pathway and normal C3 fixation by way of the alternative pathway. The data implicate auxiliary serum factors rather than an intrinsic defect in the complement system in the opsonic alterations. Retrospective data were suggestive of an increased incidence of pneumococcal bacteremia occurring in association with reduction in opsonic activity.

Adolescent↗
PubMed1983

Treatment of occult bacteremia: a prospective randomized clinical trial.

Antibiotic therapy for children without foci of infection and at risk for bacteremia is controversial. A prospective randomized clinical trial was conducted using expectant antibiotic therapy in children at risk for bacteremia. A total of 96 children (aged 6 to 24 months) with temperature of more than 40 degrees C, no identifiable source of infection, and a leukocyte count greater than or equal to 15,000/microL and/or sedimentation rate greater than or equal to 30 were enrolled. The following tests were performed on all children: blood culture, chest roentgenogram, urinalysis, and urine culture. A lumbar puncture was performed if a child was 12 months or less. Patients were randomized to receive either no antibiotic therapy or Bicillin C-R, 50,000 U/kg intramuscularly, followed by penicillin V, 100 mg/kg/d, orally four times a day for three days. Patients were examined at 24 and 72 hours. Fifty patients were treated expectantly and 46 received no antimicrobial therapy. Ten of the 96 patients were bacteremic (nine had Streptococcus pneumoniae, one had Haemophilus influenzae). Four of the five children treated for bacteremia showed improvement at the first follow-up visit (afebrile and no obvious focus of infection). The five untreated patients showed no improvement; four patients developed focal infections (two had meningitis, two had otitis media) (P less than or equal to .05, Fisher exact test). No complications of expectant therapy were detected. Thus, expectant antibiotic therapy for children who have no obvious source of infection and who meet these criteria associated with occult bacteremia is warranted.

Child, Preschool↗
PubMed1983

Pediatric hematologic and oncologic emergencies.

Acute hematologic-oncologic problems fall into two groups, those that require immediate assessment, diagnosis, and therapy, and those that require attention but are not life threatening if treated appropriately. Both types are considered in this article, which discusses hemorrhagic disorders; anemias, with special emphasis on patients with sickle cell disease; an approach to fever and infection in the immunocompromised child; and oncologic disorders that may be life threatening.

Anemia, Hemolytic↗
PubMed1979

Methotrexate and asparaginase combination chemotherapy in refractory acute lymphoblastic leukemia of childhood.

Two groups of children with refractory acute lymphoblastic leukemia were treated with a regimen of methotrexate (MTX) and asparaginase (Asn'ase) based on studies of the effect of MTX in vitro on human lymphoblasts exposed to Asn'ase. Induction therapy in 12 children produced 4 complete remissions, 3 partial remissions, and 5 failures. Responsiveness to Asn'ase seemed necessary for successful induction with the drug combinations. Maintenance therapy in 18 children produced a median hematologic remission of 31 weeks (range 3-85 weeks). During remission, 2 children developed central nervous system leukemia and 2 died of infection. The mean maximally tolerated dose of MTX was 361 mg/m2. The results of this trial suggest therapeutic synergy in maintenance therapy and the capability of Asn'ase to attenuate MTX toxicity.

Adolescent↗
PubMed1979

A new syndrome of refractory sideroblastic anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction.

In the past decade, we have studied four unrelated children with what we believe is a previously unreported disorder affecting the bone marrow and exocrine pancreas. During infancy these patients had the onset of severe, transfusion-dependent, macrocytic anemia plus a variable degree of neutropenia and thrombocytopenia. Their bone marrows had normal cellularity but were characterized by remarkable vacuolization of erythroid and myeloid precursors, hemosiderosis, and ringed sideroblasts. The vacuoles probably represented manifestations of cellular degeneration and death. In two patients, in vitro bone marrow cultures showed abnormal erythroid and myeloid progenitor cell growth and, in one child, abnormal vacuolated erythroid colonies. Family histories were unrevealing, parents were hematologically normal, and both sexes were involved. There was no evidence of specific nutritional deficiencies or exposure to agents associated with marrow vacuolization. A number of therapeutic interventions produced no effect. One child had clinical malabsorption. This child and one other had extensive pancreatic fibrosis at autopsy. The other two patients had findings indicating exocrine pancreatic dysfunction. Two children had splenic atrophy. This new syndrome, with associated bone marrow and exocrine pancreatic dysfunctions, differs in several respects from the syndrome of pancreatic liposis and neutropenia described by Shwachman et all and Bodian et al, and from other conditions with vacuolization of the marrow or sideroblastosis.

Anemia, Sideroblastic↗
PubMed1977

Intracranial calcifications in childhood leukemia. An association with systemic chemotherapy.

Children with acute lymphocytic leukemia were examined for evidence of intracranial calcifications with roentgenograms of the skull and computerized tomography. Of 39 children in their initial complete remission, ten were found to have subcortical cerebral calcifications. Significant associations were found between the presence of cerebral calcifications and systemic treatment with large cumulative doses of methotrexate.

Adolescent↗