Acquired von Willebrand disease in Wilms' tumor patients.

PURPOSE: A prospective study was performed to determine the incidence of acquired von Willebrand disease (vWD) in children with newly diagnosed Wilms' tumor. PATIENTS AND METHODS: Fifty consecutive children with newly diagnosed Wilms' tumor were evaluated. Detailed family and bleeding histories were obtained in all cases. Laboratory evaluation included measurement of the circulating platelet count, bleeding time (BT), factor VIII (FVIII) and von Willebrand factor (vWF) levels, and ristocetin cofactor (RCoF) activity. A vWF multimer analysis was obtained in all cases in which vWD was suspected. RESULTS: Four of 50 (8%) consecutive children with a diagnosis of Wilms' tumor were found to have acquired vWD. Laboratory findings indicated type III vWD in two patients and type I vWD in the other two. CONCLUSIONS: The incidence of acquired vWD in association with Wilms' tumor merits further study through a large prospective trial. Such a trial should include careful family and clinical bleeding histories plus measurement of a platelet count, BT, coagulant FVIII and vWF levels, RCoF activity, and vWF multimer analysis. The response to 1-desamino-8-D-arginine vasopressin (DDAVP) should be tested in all patients with Wilms' tumor and acquired vWD, including patients with a type III profile, before an invasive procedure is performed. Successful use of DDAVP may avoid exposure of affected patients to blood products.

The HIV information project for transfusion recipients a decade after transfusion.

OBJECTIVE: To gather information on which to base decisions about a general notification program for pediatric patients a decade after their receiving transfusions. DESIGN: The physicians of a cohort of 1793 patients who underwent cardiac surgery were sent letters asking them to contact and counsel patients identified from cardiovascular surgery and blood bank databases about their risk for human immunodeficiency virus (HIV) infection. Questionnaires were used to collect data about physicians' HIV practices; telephone interviews were conducted to collect information about patients' and parents' knowledge and attitudes about HIV and transfusions. Because of unexpected media interest, questionnaires and interviews were modified to include questions about the source of information. The HIV-testing status of patients reported by physicians was anonymously cross-referenced with specimens received by the Laboratory Services Branch, Ontario Ministry of Health, Toronto. SETTING: A large Canadian pediatric tertiary care hospital in Toronto. PARTICIPANTS: Seven hundred ninety-three patients undergoing cardiopulmonary bypass between 1980 and 1985. RESULTS: The HIV Information Project successfully reached most (approximately 75%) of this cohort and, with the help of the media, many other at-risk transfusion recipients. The information was new for many; almost all informed wanted to undergo testing. The seroprevalence of this group that received multiple transfusions was, at minimum, 8.5 patients in 1000. Six previously unsuspected HIV-seropositive cases were diagnosed. CONCLUSIONS: Although we had assumed that most patients receiving transfusions would be aware of their risk for HIV infection, our results indicate that, even a decade after the transfusion, many recipients were not aware of the risk and wanted to undergo testing. Testing identified asymptomatic infected patients.

Coagulation plasma factor levels are early indicators of graft nonfunction following liver transplantation in children.

Following liver transplantation, the decision to retransplant in cases in which graft function is marginal must be taken early. Plasma coagulation factor monitoring was evaluated as an early predictor of graft failure requiring retransplantation in the first posttransplant week. Plasma levels of fibrinogen, factors V, VII, VIII, IX, antithrombin III, protein C, and plasminogen were measured in all patients at 0, 12, 24, 48, 72, 96, and 120 hours posttransplant in 46 patients who received 56 grafts and results were compared between livers that failed early (group 1) and those that functioned adequately (group 2). Six grafts were included in group 1: one patient died before retransplantation, four were retransplanted once, and one patient was retransplanted twice. Three grafts had primary nonfunction (PNF), 2 had obstructed portal veins, and 1 had a long period of warm ischemia during the initial transplant. In group 1, plasma levels of factor V were significantly lower than in group 2 at 24, 48, and 72 hours posttransplant (21.2% +/- 14.2%, 12.4% +/- 4.5%, and 13.0% +/- 5.0% v 39.1% +/- 23.9%, 48.8% +/- 31.9%, and 60.9% +/- 25.9%; P less than .05, P less than .01, and P less than .005, respectively). Similarly, plasma levels of factor VII were significantly lower in group 1 over the same period of time (7.3% +/- 2.7%, 4.2% +/- 1.8%, and 4.7% +/- 2.5% v 27.4% +/- 17.1%, 34.1% +/- 21.6%, and 34.8% +/- 18.6%, respectively; P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of small bowel radiation enteritis by capsule endoscopy.

We report a case of radiation-induced enteritis of the small bowel diagnosed by capsule endoscopy. A 67-year-old woman, who had received radiotherapy for a carcinoma of cervix 10 years ago, presented with passage of tarry stool and anaemia. The gastroscopy results were normal and the small bowel enema showed no abnormalities, but colonoscopy revealed altered blood clots in the right-sided colon and in the terminal ileum. M2A capsule endoscopy was subsequently performed that showed an ulcer and stricture at the distal ileum. The capsule, however, became lodged at this stricture site caused by the stenosis. A small bowel resection was performed to remove both the diseased section and the capsule, and the patient made an uneventful recovery.

Acute tumour lysis syndrome with no evidence of tumour load.

Acute tumour lysis syndrome (ATLS) is a well-recognised complication of the treatment of a variety of malignant disorders in which a large mass of disease is obvious. ATLS may, however, occur even in the absence of bulk disease. We present two cases which, together with a review of previously reported cases, suggest that a cause of this rare phenomenon is primary renal lymphoma which subsequently develops into the leukaemic phase. This is supported by the observation that some bone marrow aspirates which are normal at the time of ATLS have shortly afterwards demonstrated lymphoblasts. Renal biopsy may not exclude primary lymphoma of the kidney. In excluding lymphoproliferative disease in the differential diagnosis of acute hyperuricaemia, the importance not only of bone marrow examination but of exhaustive investigation of the kidneys is stressed.

Hyperkalaemia during massive blood transfusion in paediatric craniofacial surgery.

Children undergoing major craniofacial surgery (MCFS) often require transfusion in excess of one blood volume. Therefore they were the subject of a retrospective review which looked at the longitudinal trend of plasma potassium concentration [K+] during surgery. Ten of eleven children had a statistically significant increase in plasma potassium concentration during their intraoperative course and in five the potassium concentration exceeded 5.5 mmol.L-1. This was in contrast to the stable intraoperative plasma [K+] observed in a control group which did not receive blood transfusion. All MCFS children received a blood transfusion with red blood cell concentrates (RBCconc). The age of the units of RBCconc which had been transfused was 16.1 +/- 8.4 days. The amount of extracellular potassium in 28 units of RBCconc was determined in order to estimate the amount of free potassium (Kdose) which the MCFS group received. The plasma [K+] in units of RBCconc less than 1 week of age was less than 20 mmol.L-1, whereas in units aged greater than 2 weeks it was greater than 40 mmol.L-1. The estimated Kdose was 0.2-1.6 mmol.kg-1. We concluded that the amount of extracellular potassium in units of RBCconc was clinically important and may give rise to hyperkalaemia during massive blood transfusion.

Reticulated platelet counts in the diagnosis of acute immune thrombocytopenic purpura.

PURPOSE: Bone marrow aspiration is often performed to diagnose childhood acute immune thrombocytopenic purpura (ITP) because no non-invasive investigation to confirm the diagnosis is routinely available. Reticulated platelets (RPs--young platelets characterized by a high RNA content--increase with increased platelet production and may be useful in the diagnosis of ITP. METHODS: To assess the role of RP counts in distinguishing ITP, we compared counts from 15 consecutive patients with ITP with counts from 20 patients with acute lymphoblastic leukemia (ALL), 10 with aplasia, and 27 healthy normal children. Whole blood in edetic acid (EDTA) was labelled with a platelet-specific monoclonal antibody and incubated with thiazole orange (TO). A standard gate was set to achieve a fluorescence value of 1.3 +/- 0.5% for control lyophilized platelets. RESULTS: Patients with ITP had a mean (+/- 1 standard deviation) RP level of 32.9 +/- 10.2%; patients with ALL, 6.6 +/- 3.1%; patients with aplasia, 3.4 +/- 2.0%; and normal patients, 7.9 +/- 2.9%. The difference in RPs between the ITP group and the ALL, aplasia, and normal groups was highly significant (p < 0.0001 each), with no significant difference between the non-ITP groups (p = 0.12). CONCLUSIONS: Measuring RPs by this simple whole-blood cytometric technique discriminated very well between the acute ITP and non-ITP groups. This test has a strong positive predictive value and may prove very useful in the assessment of childhood acute ITP and the screening of candidates for bone marrow aspiration.

Diagnostic value of the Hemalog D-90 in classifying acute childhood leukaemias.

Accurate classification of the acute leukaemias is dependent not only on morphological characteristics, but also on cytochemical staining properties of the blasts in peripheral blood and bone marrow. This study was undertaken to evaluate the Hemalog D-90, an automated cytochemistry system for white cell differential counts, as an adjunct to conventional microscopy in the classification of acute childhood leukaemias. Fifty-two patients were classified according to morphology and cytochemical reactions of the cells obtained from peripheral blood. In 29 with classical acute lymphoblastic leukaemia (ALL), the Hemalog D showed the lymphoblasts to be non-peroxidase staining and these were recorded mainly as lymphocytes. In contrast, the blasts of eight patients with acute myeloblastic leukaemia (AML) were peroxidase positive, being recorded as neutrophils. Of the remaining 15 patients, 10 were classified as "Probably ALL' because they lacked some of the morphological or cytochemical criteria for classical ALL, while five were unclassifiable. However, in all these 15 patients the Hemalog D results were similar to those obtained in patients with classical ALL. We concluded that the Hemalog D was a useful adjunct in distinguishing ALL from AML, including the morphologically indistinct types.

Compound heterozygosity for two genotypes of alpha-thalassemia-2: hematological, biosynthetic and DNA studies.

Hemoglobin and DNA gene analyses were carried out in two Black Canadian families. In Family Q, both the parents and the brother were found to be heterozygotes for alpha-thalassemia-2 with the following alpha-genotypes: -alpha 3.7/alpha alpha, -alpha 4.2/alpha alpha and -alpha 4.2/alpha alpha, respectively. In Family C, the mother was found to be a homozygote for alpha-thalassemia-2 with the alpha-genotype of -alpha 3.7/-alpha 3.7. In both families, the propositi were compound heterozygotes for alpha-thalassemia-2 with the alpha-genotype of -alpha 3.7/-alpha 4.2. The propositus in Family C was also a sickle cell trait carrier. The usefulness of DNA gene analyses in family studies of hemoglobinopathy was discussed.

An alpha-globin gene initiation codon mutation in a black family with HbH disease.

The molecular basis of hemoglobin H disease in a Black family of Canadian origin was investigated. Affected individuals had a combination of deletion and nondeletion alpha-thalassemia mutations on different chromosomes. Cloning and sequencing of the DNA of one member with the nondeletion form revealed a new thalassemia mutation, an A----G substitution, in the initiation codon of the remaining alpha-globin gene of a rightward (-alpha 3.7) deletion chromosome. This mutation abolished an Ncol restriction site and therefore is detectable in genomic DNA by Southern blot analysis.

A new frameshift beta zero-thalassemia mutation (codons 27-28 +C) found in a Chinese family.

A new beta zero-thalassemia mutation, a frameshift mutation with an insertion of a single cytosine nucleotide in codon 27-28, is described. The propositus, who is compound heterozygous for this mutation and the IVSII-654 C----T beta zero-thalassemia mutation, has the phenotype of severe beta-thalassemia major.

Hb E/Hb LeporeHollandia in a family from Bangladesh.

We describe a family from Bangladesh in which three children are compound heterozygotes for Hb E (alpha 2 beta 2, beta 26Glu Lys) and Hb Lepore (delta-beta fusion gene). PCR amplification and direct nucleotide sequencing established that the fusion gene is Hb LeporeHollandia, with the cross-over localized to a 40 bp window between codon 22 and IVS-1 nt 16 of the delta- and beta-globin genes. This unusual combination of mutations is associated with a relatively mild clinical phenotype, with all three affected siblings having microcytic anemia of moderate severity without the need for transfusions.

A second observation of the fetal methemoglobin variant Hb F-M-Fort Ripley or alpha 2G gamma 2(92)(F8)His----Tyr.

We have identified a second baby with the fetal methemoglobin F-M-Fort Ripley. It was observed in a Caucasian infant from Canada; at least eleven additional members of that family were known to have had a neonatal cyanosis similar to that seen in the propositus and in a previously described baby (2). Sequencing of amplified DNA that included (part of) the G gamma gene greatly facilitated the characterization. The G gamma X chain was readily isolated by reversed phase high performance liquid chromatography; its quantity was approximately 12.5% of total gamma. Interestingly, the baby also carried the A gamma T mutation on one chromosome, either in cis or in trans to the G gamma X mutation. Hb F-M-Fort Ripley could be isolated in reasonably pure form by DEAE-cellulose chromatography. The isolated Hb FX was unstable, had spectral changes characteristic for the M-hemoglobins, while its methemoglobin derivative reacted rapidly with cyanide. Oxygen affinity data could not be obtained. It is suggested that the formation of a rather large amount (approximately 25%) of mixed hybrids (alpha 2G gamma X.gamma) with low oxygen affinity is the main cause for the occurrence of the neonatal cyanosis.

Reduction of plasma volume after storage of platelets in CP2D.

BACKGROUND: There has been concern that further deterioration might occur if stored platelets are centrifuged to reduce their volume. Although such centrifugation appears to have minimal effect on platelets in CPDA-1 (osmolarity, 470 mOsm) there is no information on the situation with CP2D (580 mOsm). STUDY DESIGN AND METHODS: Platelet concentrates from CP2D packs were sampled at 1 and 5 days and after centrifugation was used to reduce the plasma volume to 10 mL. The aggregation, hypotonic shock response, morphology, pH, and lactate, glucose, pCO2 and pO2 levels were assessed, and values were compared to those seen with CPDA-1. In addition, blood was collected from the same donors into both CP2D and standard sodium citrate anticoagulant in an anticoagulant-to-blood ratio of 1:8 and the aggregation response of the fresh platelets was measured. RESULTS: Collection of blood into CP2D results in an immediate reduction of the platelet aggregation response when compared to that found after collection of blood into sodium citrate or CPDA-1. Aggregation is further decreased after storage; however, these changes and those for hypotonic shock, pH, lactate, glucose, and pCO2 are similar to those seen for CPDA-1. Additional centrifugation did not cause further change. CONCLUSION: Platelets stored in CP2D have reduced in vitro function after 5 days of storage, but subsequent centrifugation to reduce the plasma volume does not further alter these platelets.