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Biomedical subjects

R R Chilcote

Publications and source records attributed to R R Chilcote.

At least 37 records · Page 2Linked to original sources

Childhood non-Hodgkin's lymphoma. The results of a randomized therapeutic trial comparing a 4-drug regimen (COMP) with a 10-drug regimen (LSA2-L2).

Members of the Childrens Cancer Study Group treated 234 eligible patients in a randomized trial designed to study the relative effectiveness of two therapy programs for the treatment of childhood and adolescent non-Hodgkin's lymphoma. Two chemotherapeutic strategies were compared: a 4-drug regimen (COMP) and a 10-drug regimen (modified LSA2-L2). Failure-free survival for all patients was 60 per cent at 24 months. In patients with disseminated disease treatment success was influenced by both the histologic subtype of disease and the therapeutic regimen followed. The 10-drug program was more effective than the 4-drug program in patients with disseminated lymphoblastic disease (two-year failure-free survival rate, 76 vs. 26 per cent, respectively; P = 0.0002), whereas the 4-drug program was more effective than the 10-drug program in those with nonlymphoblastic disease (57 vs. 28 per cent, respectively, P = 0.008). The less toxic, more easily administered 4-drug regimen was as effective as the 10-drug regimen in patients with localized disease (89 vs. 84 per cent, respectively).

Adolescent↗

Neutropenia, recurrent bacterial infections, and congenital deafness in patients with monocytopenia. Absence of peripheral blood colony-stimulating activity.

The factors that regulate granulopoiesis in vivo are unclear, but recent evidence suggests a role for monocytes; these cells produce a leukopoietin termed colony-stimulating activity (CSA), which stimulates growth of colonies of myeloid cells in vitro. We describe a family in which three of four siblings had neutropenia with myeloid marrow hypoplasia, deafness, and monocytopenia. Two of the three affected siblings died of bacterial septicemia; the third sibling, who resided in a long-term care facility, remained relatively free of infections. Studies of this patient's peripheral blood disclosed deficient CSA production consistent with the virtual absence of monocytes. These findings support the purported role of monocytes as a source of peripheral blood leukopoietic factors.

Agranulocytosis↗

Acute non-lymphoid leukemia.

Acute non-lymphoid leukemia is a group of hematologic neoplasms which have been the subject of intensive basic and clinical research. These studies have led to a better understanding of the genetic basis of leukemia and may ultimately help establish the molecular mechanisms of malignant transformation. They also have increased our understanding of myeloid differentiation. As a result of clinical trials, we can now induce a clinical remission in a large majority of patients with acute non-lymphoid leukemia. Future studies will attempt to lessen toxicity and to maximize the response rate. Many of these advances will come from improvements in supportive care given during the periods of therapy-related marrow aplasia. The role of intensive chemotherapy to prolong remission duration and to increase the usefulness of allogenic bone marrow transplantation will be clarified during the next several years.

Acute Disease↗

The hypereosinophilic syndrome and lymphoblastic leukemia with extra C-group chromosome and q14+ marker.

Hypereosinophilic syndrome is probably a disease of diverse etiologies. We studied the bone marrow of a patient with HES and found a population of L-1 lymphoblasts. These cells failed to grow in double-layer agar cultures, were "null cells," and contained a 14q+ marker chromosome consistent with a malignant lymphoproliferative disorder. Complete remission was induced with vincristine, prednisone, and L-asparaginase but the patient died from the consequences of cardiac fibrosis. An underlying lymphoproliferative process should be carefully sought in patients with HES to afford the best opportunity for cure.

Asparaginase↗

Correlation of karyotype with clinical features in acute lymphoblastic leukemia.

We studied the clinical and karyotypic features of 50 patients with acute lymphoblastic leukemia, including 33 American and 17 Japanese patients, at two institutions. Clonal chromosome abnormalities were found in 39 of the 50 patients (78%) at diagnosis. Eleven patients had diploidy (N patients). Among the 39 aneuploid patients, 17 had pseudodiploidy (A1 patients), eight had hyperdiploidy with 47 to 49 chromosomes (A2 patients), nine had hyperdiploidy with 50 to 59 chromosomes (A3 patients), and five had other chromosome abnormalities. Of 14 patients whose chromosomes were also studied at relapse, eight had karyotypic progression, five had abnormalities identical or similar to those observed at diagnosis, and one had a change of karyotype from diploidy to aneuploidy. The median age and the median WBC of A1 patients were higher than those of any other group of patients, although one-third of the patients had WBC below 20 x 10(3)/microliters, and they often had leukemic cells of T-cell or B-cell lineage. The A2 patients were relatively old and tended to have higher WBC. The N patients were relatively young and tended to have low WBC, although these tendencies were not as marked as those in A3 patients. The A3 patients had longer survival times than the A1 (p = 0.003) or A2 (p = 0.002) patients. Also, N patients had longer survival times than A1 (p = 0.03) or A2 (p = 0.05) patients. The difference in survival times between A3 and N patients was not significant. Our study demonstrated that the karyotype is correlated with survival and with other recognized prognostic factors. However, in some A1 and A2 patients, the karyotype was a more reliable factor in indicating a poor prognosis than was the WBC or age.

Adolescent↗

Immunologic and virologic studies of measles inclusion body encephalitis in an immunosuppressed host: the relationship to subacute sclerosing panencephalitis.

An immunosuppressed child with acute lymphoblastic leukemia in clinical remission developed measles inclusion body encephalitis (MIBE). Although measles antigen and nonbudding measles virus nucleocapsids were detected in brain tissue, no virus was isolated. Immune precipitation of measles virus proteins with the patient's serum showed no detectable antibody to virus M protein, a finding that has been reported in subacute sclerosing panencephalitis (SSPE). The virologic and immune precipitation studies suggest a similar virus mutation in MIBE and SSPE. The pathogenesis of the two diseases may also be similar.

Adult↗

Chromosome abnormalities in Down's syndrome patients with acute leukemia.

Chromosome and cytologic studies were performed on three Down's syndrome (DS) patients with acute nonlymphocytic leukemia (ANLL). All three patients had an aneuploid clone in their leukemic cells: 50, XX, +6, +19, +21, +22, +8, XX, +21, and 47,XY, +8, - 21 +dic(21;21)(p13;p11). Every patient appeared to have acute undifferentiated leukemia when the blast cells were examined with Wright-Giemsa stain; cytochemistry studies, however, showed that the leukemic blasts were in an early stage of myeloid differentiation. The two patients with +8 had a preleukemic phase; the blast cells of the patient with an extra no. 19 and no.22 could not be differentiated morphologically from those of the two patients with an extra no. 8. Our findings and a review of data on 40 other patients suggest that most DS children with ANLL have hyperdiploidy, which is usually related to gains of C, F, and /or G chromosomes, and that the abnormalities of +8 and of +19, +22 in DS children may be associated with acute leukemia (AL) in an early stage of myeloid differentiation.

Acid Phosphatase↗

Atypical bleeding in hemophilia: application of the conversion model to the case study of a child.

Although it has been suggested that psychosocial events may trigger bleeding in patients with hemophilia, few specific instances have been described. In this report we interpret a series of atypical bleeding episodes in a child with a factor VIII deficiency. Although the specific pathophysiologic events that led to bleeding into the elbow are unknown in this child, they are probably similar to those of "psychogenic purpura." It is likely that these episodes of atypical bleeding can be interpreted in terms of conversion model and that conversion reactions in children required involvement by at least one parent.

Adolescent↗

Changes in outflow facility in experimental hyphema.

To characterize the pathophysiology of hyphema clearance, we studied changes in the facility of outflow in experimental hyphema in freshly enucleated rabbit eyes. Hyphemas, with washed normal or sickled red cells (RBCs) (suspended in isotonic phosphate buffer to obtain a hematocrit value comparable to that of whole blood) and occupying 50% to 100% of the anterior chamber volume, caused a marked cell "crowding" in the chamber angle and an increase in the outflow resistance; the facility stabilized at a value 60% lower than the control (p = < 0.001). No significant change in outflow facility was observed in hyphemas of either RBC type occupying 25% of the anterior chamber volume (p = N.S.). Whole blood hyphema occupying 50% of the anterior chamber volume reduced the facility of outflow by 80% of the control mock aqueous value (p = < 0.001); a comparison with 50% hyphema produced by washed RBCs indicated a significant contribution by the plasma (fibrin) component (p = 0.0025) in increasing the resistance to outflow.

Anemia, Sickle Cell↗

Septicemia in association with acute lymphoblastic leukemia.

Fifty consecutive episodes of septicemia were studied in 41 children who had acute lymphoblastic leukemia. Seventy-six percent of these episodes occurred when the absolute granulocyte count was 200/mm3 or less and were caused by gram-negative enteric and gram-positive mucocutaneous bacteria. In eight patients, Streptococcus pyogenes was isolated at the time when ALL was diagnosed. Multiple anaerobic and aerobic isolates from a single blood culture were associated with abdominal distress, whereas Streptococcus pneumoniae and Hemophilus influenzae septicemia occurred in associated with respiratory illnesses. When patients with severe compromise of anatomic barriers or respiratory disease were excluded, 94% of all patients with septicemia had an AGC of less than 200/mm3. The data provide guidelines for treatment for febrile patients with ALL based upon the AGC, the phase of the disease, and on the presence of associated respiratory or abdominal findings.

Acute Disease↗

In vitro characteristics of childhood leukemic monoblasts.

Leukemic monoblasts obtained from three children were evaluated for their in vitro physiologic characteristics. These monoblasts were alpha naphthyl acetate esterase positive, exhibited glass adherence, had IgG membrane receptors, phagocytized latex particles with subsequent nitroblue tetrazolium (NBT) reduction, and matured to macrophages in vitro, either when adherent to glass slides or in feeder layer suspensions. Employing the double layer in vitro bone marrow culture technique, leukemic marrows from these children failed to produce colonies in culture in the presence or absence of normal feeder layers. Varying the concentration of leukemic cells in the feeder layers failed to augment colony growth from normal bone marrows. Although monoblasts were observed to mature to macrophages in vitro, no increase in colony stimulating factor activity was observed with aging of the feeder layers. These studies suggest that childhood leukemic monoblasts lack the ability to produce colony stimulating activity, differing in this respect from monoblastic leukemia in adults.

Adolescent↗

Sudden death in an infant from methemoglobinemia after administration of "sweet spirits of nitre".

The administration of "sweet spirits of nitre" (4% ethyl nitrite CH3CH2ONO in 70% ethyl alcohol) was followed by acute methemoglobinemia and severe anoxic metabolic acidosis in infant twins, Methylene blue administration reversed methemoglobinemia in both, but one twin died from the consequences of hypoxemia. Hemoglobin electrophoresis and methemoglobin reductase determinations were normal for age. This medicine is available without prescription and contains the potent oxidant ethyl nitrite. In infants with sudded death or onset of cyanosis, appropriate toxicological and historical information should be obtained.

Death, Sudden↗

Septicemia and meningitis in children splenectomized for hodgkin's disease.

Retrospective evaluation of the occurrence of septicemia and meningitis in 200 children who had staging laparotomy iwth splenectomy for Hodgkin's disease revealed 20 episodes occurring in 18 children. Symptoms were usually fulminant; only 10 of these patients survived their episode. Infections occurred eight days to three years after splenectomy. Adolescents, as well as younger children, were affected; half were older than 10 years of age. Leukopenia was not a major factor in onset or survival since the average white-cell count was 12,000 in both survivors and children who died. Pneumonococcus accounted for 50 per cent, and streptococcus for 15 per cent of infections; there was one episode each of Haemophilus influenzae and meningococcus; in 25 per cent, no organism was isolated. Predominance of penicillin-sensitive organisms and high mortality suggest that penicillin prophylaxis and the protection offered by bacterial vaccines should be evaluated in children with Hodgkin's disease whose staging laparotomy includes splenectomy.

Adolescent↗

Acquired agammaglobulinemia after a life-threatening illness with clinical and laboratory features of infectious mononucleosis in three related male children.

Three males in one family (two siblings and one maternal cousin) had an illness with cervical adenopathy, hepatosplenomegaly, and a fulminant febrile course. In the two survivors agammaglobulinemia developed. One of them became ill at the age of six months and had an Epstein-Barr-virus antibody titer of 1:10 during illness and convalescence. The white-cell count was 120,000 with 90 per cent lymphocytes, most being atypical and forming increased numbers of sheep erythrocyte rosettes. IgM was elevated, IgA normal and IgG decreased. Subsequently, all immunoglobulins were absent, and the Epstein-Barr-virus antibody titer became negative. Peripheral B-cell number remained normal, but abnormal lymph-node architecture associated with failure to respond to antigenic challenge indicated B-cell dysfunction. The pathogenesis of this entity may involve an abnormal T-cell response to transformation of B cells by Epstein-Barr virus, leading to B-cell dysfunction and agammaglobulinemia.

Agammaglobulinemia↗

Glucose phosphate isomerase deficiency with hereditary nonspherocytic hemolytic anemia.

Eight children (5 living, 3 deceased) with severe hereditary nonspherocytic hemolytic anemia caused by glucose phosphate isomerase deficiency have been observed in two Kentucky and Indiana families. All affected children were severely anemic in early life. Three deaths occurred in young patients who did not receive adequate transfusions of blood or whose parents refused to permit splenectomy. Splenectomy generally abolishes the requirement for blood transfusion. No patient has required regular transfusion of blood after puberty. Growth and development have been surprisingly normal and no patient has died of infection. The anemia is expressed as an autosomal recessive trait, but the enzyme variant can be detected in hematologically normal heterozygotes. The abnormal isomerase molecule is heat labile and is contained in neutrophils and lymphocytes as well as in erythrocytes.

Adult↗