Changes in plasma methionine and total homocysteine levels in patients receiving methotrexate infusions.

Methotrexate reduces intracellular pools of 5-methyltetrahydrofolate and could result in reduced conversion of homocysteine to methionine by methionine synthetase. This study was designed to investigate the effects of moderate dose to very high dose methotrexate on methionine and total homocysteine as reflections of methotrexate induced intracellular events. Methionine and total homocysteine were measured prior to, during, and following twenty-six 24-h i.v. infusions of 33.6 g/m2 methotrexate (very high dose methotrexate) in 16 children with acute lymphocytic leukemia and seven 4-h i.v. infusions of 8 g/m2 methotrexate (high dose methotrexate) in 5 children with osteogenic sarcoma. Amino acids were measured by gas chromatography/mass spectrophotometry. Mean methionine levels decreased by 70.0 +/- 3.1% (SE) with very high dose methotrexate and 72.6 +/- 5.9% with high dose methotrexate at 24 and 4.5 h, respectively, after beginning methotrexate infusions. Mean total homocysteine levels increased by 61.7 +/- 3.1% with very high dose methotrexate and 55.6 +/- 17.5% with high dose methotrexate at 36 and 24 h, respectively, after beginning methotrexate infusions. No consistent or significant changes were noted in levels of total cysteine, leucine, isoleucine, or valine. Similar changes did not occur in patients receiving prednisone, vincristine, daunomycin, and intrathecal methotrexate as therapy for acute lymphocytic leukemia. These changes in homocysteine and methionine may reflect biological effects of methotrexate that may predict cytotoxicity of methotrexate.

TEL-AML1 fusion identifies a subset of children with standard risk acute lymphoblastic leukemia who have an excellent prognosis when treated with therapy that includes a single delayed intensification.

The Children's Cancer Group (CCG) found that children with moderate risk acute lymphoblastic leukemia (ALL) had an improved 5-year event-free survival (EFS) rate when treated with therapy that included a doubled delayed intensification (DDI) vs a single DI (SDI) phase. Because of increased toxicity with DDI, it is important to determine whether subgroups of children with ALL can be identified who have excellent outcomes with SDI therapy. TEL-AML1 fusion and hyperdiploid DNA content are present in the leukemic blasts of significant proportions of children with ALL and have been associated with an excellent prognosis. In this study, we retrospectively examined the impact of TEL-AML1 status and ploidy on treatment outcome in a cohort of 75 children with standard risk ALL treated at our institution between 1983 and 1993 with SDI therapy. TEL-AML1 fusion was present in 19/43 (44%) evaluable cases. Fifteen of 56 (27%) evaluable cases were classified as hyperdiploid based on a modal chromosome number of >/=51 and/or a DNA index of >/=1.16. The 7-year EFS was 81% for the 19 TEL-AML1-positive patients vs 54% for the 24 TEL-AML1-negative patients (P = 0.0264). In multivariate analyses, TEL-AML1-positive status was associated with a superior EFS (P = 0.02) even when the intial white blood count was included in the model. Overall survival (OS) at 7 years for TEL-AML1-positive patients was 100% vs 83% for TEL-AML1-negative patients (P = 0.0677). There were no differences in 7-year EFS or OS based on ploidy comparisons. These results underscore the need to examine closely the effects of treatment intensification on specific biologically defined subgroups of children with ALL.

Residual bone marrow leukemic progenitor cell burden after induction chemotherapy in pediatric patients with acute lymphoblastic leukemia.

We used highly sensitive multiparameter flow cytometry and blast colony assays to quantify the leukemic progenitor cell (LPC) burden of postinduction chemotherapy bone marrows from newly diagnosed and relapsed pediatric patients with acute lymphoblastic leukemia (ALL). Of 890 newly diagnosed patients, 243 (27%) had detectable LPC in the postinduction bone marrow samples with an average (mean +/- SE) LPC content of 22+/-9 LPC/10(6) mononuclear cell (MNC; range, 0-7199/10(6) MNC; median, 0/10(6) MNC). By comparison, 24 of 50 (48%) patients with relapsed ALL had detectable LPC in their postinduction bone marrow specimens (P = 0.003), and their average LPC content was 202+/-139 LPC/10(6) MNC. Fewer patients with B-lineage ALL (170 of 786; 22%) than patients with T-lineage ALL (73 of 104; 70%) harbored residual LPC in their postinduction bone marrow specimens (P < 0.0001). This correlation with immunophenotype was independent of the National Cancer Institute risk classification. Similarly, 19 of 44 (43%) patients with relapsed B-lineage ALL versus 5 of 6 (83%) patients with relapsed T-lineage ALL harbored residual LPC in their postinduction bone marrow specimens (P = 0.09). Among newly diagnosed patients, those with high-risk ALL seemed to have larger numbers of residual LPC in their bone marrow after induction chemotherapy than those with standard risk ALL (53+/-26, n = 286 versus 7+/-1, n = 604, P = 0.04). LPC of patients with standard risk ALL who had a slow early marrow response at day 7 seemed to be more resistant to the three-drug induction chemotherapy than patients who had a rapid early marrow response. Overall, the order of chemosensitivity of LPC was: newly diagnosed standard risk B-lineage > newly diagnosed higher risk B-lineage > newly diagnosed standard risk T-lineage > newly diagnosed higher risk T-lineage > relapsed B-lineage > relapsed T-lineage. Notably, LPC- patients whose end-of-induction remission bone marrow specimens had zero LPC had an excellent early event-free survival outcome. Within the standard and high-risk subsets, LPC- patients had a 2.6-fold lower and 2.4-fold lower incidence of events, respectively, than LPC+ patients. At 6 months, 12 months, as well as 24 months, the ranking order for better event-free survival was: standard risk, LPC- > high risk, LPC- > standard risk, LPC+ > high risk, and LPC+.

Interleukin-1 enhances murine granulopoiesis in vivo.

Interleukin-1 (IL-1), a monokine involved in host response to infection and inflammation, has recently been shown to stimulate production of granulocyte-monocyte colony-stimulating factors (CSFs) from a variety of cell types in vitro. The purpose of this study was to investigate the effects of human IL-1 on granulopoiesis in vivo. CF1 female mice were injected with a single dose of either highly purified human IL-1 or recombinant human IL-1 alpha (rIL-1 alpha). Heat-inactivated IL-1 or rIL-1 alpha served as controls. Physiologic doses of the IL-1 preparations were initially established by evaluating neutrophil egress from bone marrow (BM). Significant peripheral neutrophilia developed 3 h after injection of 10 U (doubling units) purified IL-1, in association with decreased marrow neutrophils. Significant neutrophilia occurred 6 h after injection of 5 x 10(3) U (half-maximal units) rIL-1 alpha. Serum colony-stimulating activity (CSA) and BM colony formation (CFU-GM) were subsequently measured in standard agar culture at various times following injection. A significant rise in CSA occurred between 3 and 6 h after injection of purified IL-1, and a significant increase in BM CFU-GM developed 48 h after injection. Similar increases in CSA and CFU-GM occurred following injection of rIL-1 alpha. These results suggest that IL-1 may play an important role in the regulation of granulopoiesis in vivo by enhancing the production of CSFs required for myeloid proliferation.

N-ras gene mutations in childhood acute non-lymphoblastic leukemia.

In view of the potential role for ras activation in leukemogenesis, we have screened a number of children with acute non-lymphoblastic leukemia (ANLL) for activating point mutations at codons 12, 13 and 61 of the N-ras proto-oncogene using panels of oligonucleotide probes in conjunction with polymerase chain reaction (PCR) gene amplification. In contrast to the frequent occurrence (approximately 30%) of N-ras mutation reported in adult ANLL, 6 of 46 cases (13%) at the time of diagnosis had N-ras mutations involving codons 12 and 13. In these patients we also determine whether presenting clinical symptoms, cellular pathology, karyotype, or eventual outcome distinguished them from the ras-negative group. N-ras activation tended to be associated with a higher white blood cell count at diagnosis (mean of 225,000/microliters vs 91,000/microliters) and fewer remissions obtained after 28 days of therapy (3/6, 50% vs 24/32, 75%). It is possible that activation of N-ras oncogene may be involved in the progression of some cases of childhood ANLL.

The discriminating value of serum lactate dehydrogenase levels in children with malignant neoplasms presenting as joint pain.

OBJECTIVES: To determine if serum lactate dehydrogenase levels distinguish patients with malignant neoplasm presenting with musculoskeletal complaints from patients with juvenile rheumatoid arthritis who reported similar symptoms. DESIGN: Retrospective case-comparison study. SETTING: Tertiary care, outpatient clinics. PATIENTS: Twelve patients with malignant neoplasms who presented with arthritis or arthralgias and normal complete blood cell counts and blood smears in whom rheumatologic diagnosis was initially made were compared with 24 children with a final diagnosis of juvenile rheumatoid arthritis. The patients with malignant neoplasms all had normal blood counts and elevated sedimentation rates at symptom onset. INTERVENTIONS: None. RESULTS: Serum lactate dehydrogenase levels were significantly higher in the cancer patients at 2.2 times the normal values vs 0.8 times high normal for patients with juvenile rheumatoid arthritis (P =.004, Mann-Whitney U test) No significant differences were observed in white blood cell counts, hemoglobin levels, platelet counts, erythrocyte sedimentation rate, or uric acid or aspartate aminotransferase levels at initial evaluation. CONCLUSIONS: Serum lactate dehydrogenase values may distinguish patients with malignant neoplasms from those with rheumatic disease early in the course of illness when symptoms and other laboratory values are not helpful.

Plasma pharmacokinetics and cerebrospinal fluid penetration of thioguanine in children with acute lymphoblastic leukemia: a collaborative Pediatric Oncology Branch, NCI, and Children's Cancer Group study.

PURPOSE: In preclinical studies, thioguanine (TG) has been shown to be more potent than the standard acute lymphoblastic leukemia (ALL) maintenance agent, mercaptopurine (MP), suggesting that TG may be more efficacious than MP in the treatment of childhood ALL. As part of a pilot trial in which TG was used in place of MP, we studied the plasma pharmacokinetics of oral TG and measured steady-state plasma and CSF TG concentrations during a continuous intravenous infusion (CIVI) in children with newly diagnosed standard-risk ALL. METHODS: Nine plasma samples were collected after each patient's first 60 mg/m2 oral TG dose during maintenance. CIVI TG (20 mg/m2/h over 24 h) was administered during the consolidation phase of therapy, and simultaneous plasma and CSF samples were collected near the end of the infusion. TG was measured by reverse-phase HPLC with ultraviolet detection. Erythrocyte TG nucleotide (TGN) concentrations were measured 7 days after a course of CIVI TG and prior to the start of each maintenance cycle. RESULTS: After oral TG (n = 35), the mean (+/- SD) peak plasma concentration was 0.46 +/- 0.68 microM and the AUC ranged from 0.18 to 9.5 microM.h (mean 1.5 microM.h). Mean steady-state plasma and CSF TG concentrations during CIVI (n = 33) were 2.7 and 0.5 microM, respectively. The mean (+/- SD) TG clearance was 935 +/- 463 ml/min per m2. Plasma TG concentrations did not correlate with erythrocyte TGN concentrations after oral or CIVI TG. The 8-OH-TG metabolite was detected in plasma and CSF. CONCLUSIONS: TG concentrations that are cytotoxic to human leukemia cell lines can be achieved in plasma after a 60 mg/m2 oral dose of TG and in plasma and CSF during CIVI of TG.

Acute megakaryoblastic leukemia in Down syndrome: orbital infiltration.

PURPOSE: To describe an uncommon ocular presentation of acute megakaryoblastic leukemia in a child with Down syndrome. METHOD: Case report. Initial manifestation of disease was bilateral proptosis with secondary exposure keratitis caused by leukemic infiltration of the orbits. RESULTS: Bone marrow biopsy and immunophenotyping established the diagnosis of acute megakaryoblastic leukemia (FAB-M7). The leukemia was treated successfully with chemotherapy, with resolution of proptosis. The patient remained in remission more than 1 year after cessation of treatment. CONCLUSIONS: Bilateral proptosis can be a presenting sign of acute megakaryoblastic leukemia, a malignancy associated with Down syndrome.

A novel method for controlling the quantity of mitomycin-C applied during filtering surgery for glaucoma.

The use of a sponge impregnated with mitomycin-C is an increasingly common practice in glaucoma surgery. The appropriate antibiotic concentration and exposure time have been considered in the literature, but not the exact amount to be used or the size of the sponge. The purpose of this study was to estimate the quantity of mitomycin-C contained in sponges prepared by different surgeons as compared to that in applicators of the type used in Schirmer's test graduation (5 x 5 mm). Four surgeons each cut and prepared 10 sponges for intraoperative use according to their usual method. The same procedure was performed with 10 Schirmer's test graduations. Each sponge and each graduation was immersed in a solution of mitomycin-C 0.2 mg/ml, and the quantity of antibiotic (microg) in each was calculated as the difference between wet and dry weight. The mean quantity (+/- SEM) of mitomycin-C contained in cut sponges was 9.6 +/- 4.4 microg (range 1.9-17.3), and the differences between surgeons were statistically significant (p<0.0001). The mean quantity of antibiotic in Schirmer's test graduation was 1.7 +/- 0.3 microg (range 1.1-2.5), and the differences between surgeons were not statistically significant (p=0.79). The quantities of mitomycin-C contained in sponges prepared for glaucoma surgery differed for a given surgeon and between surgeons. Thus, variations in the doses applied to the sclera could account for certain complications due to mitomycin-C. The use of a Schirmer's test graduation improves predictability for the quantity of mitomycin-C applied to the sclera.

Health behavior counseling at annual exams.

OBJECTIVE: To determine if patients expected and desired health behavior discussions at annual exams, and if these discussions motivated high-risk patients to modify a health behavior. METHODS: 1213 patients seen for an annual exam at Gundersen Clinic were sent a survey. Patients were asked if discussions about weight, exercise, tobacco use and stress occurred at their exam. Patients were also asked if the discussions were expected and desired and if the discussions motivated them to modify a health behavior. RESULTS: 571 surveys were returned. Over 50% of high-risk patients for each health behavior had a discussion. Patients who were overweight, obese, smoked or had excess stress were more likely to want and expect discussions than lower risk counterparts. Obese and overweight patients were also more likely to report being motivated to maintain or lose weight. CONCLUSION: Patients in need of weight, smoking and stress management counseling expected and desired behavior discussions and were motivated to modify their behavior.

[Non-immunologic factors of failure of penetrating keratoplasties. Prospective study of 119 corneal grafts at the Nantes Hospital Center in 1995]. / Facteurs non immunologiques d'échec des kératoplasties perforantes. Etude prospective de 119 greffes de cornée au CHU de Nantes sur l'année 1995.

PURPOSE: A single-center prospective study was carried out in Nantes to evaluate corneal graft outcome, while immunosuppressive treatment was used topically or systemically, during the first year. METHODS: A cohort of 119 patients underwent penetrating keratoplasty between 1-1-95 and 31-XII-95. Systematic standardized exams were performed at 15 days, 1 month, 4 months, 6 months and 1 year. Grafts were obtained from organo-cultured corneas at +31 degrees C. Intraveinous methyl prednisolone was given at the time of the surgery in most cases (82%). Corticosteroid eye drops are used in all cases and systemic Cyclosporin A was given for high-risk rejection keratoplasties (29.5%). RESULTS: The clear graft rate at 1 year is 97% for keratoconus, 87.8% for bullous dystrophies and 80.7% for regrafts. The leading causes of graft failure are: graft rejection (25%), endothelial consequences of a non controlled elevated intra ocular pressure (25%) and ocular surface disorders (16%). Prevalence and management of elevated IOP (from 8% to 20%) and ocular surface disorders (from 18% to 43%) are reported over one year. CONCLUSION: This study points out the great frequency of elevated-IOP-related disorders and ocular surface diseases in corneal graft outcome. They must be tracked down and uncompromisingly treated before and after transplantation.

[A case of Tolosa Hunt syndrome]. / Un cas de syndrome de Tolosa Hunt.

The authors review the clinical signs, results of investigations and clinical course under treatment of the Tolosa-Hunt syndrome; they illustrate their case presentation with a complete sequence of the imaging and the clinical and radiological findings of a case which fits the classical description found in the literature. They insist on the term of syndrome rather than disease because of the obvious diversity of anomalies encountered in this condition.

Meta-analysis of randomised trials comparing thiopurines in childhood acute lymphoblastic leukaemia.

Mercaptopurine has been used in continuing treatment of childhood acute lymphoblastic leukaemia since the mid 1950s. Recent advances in the understanding of thiopurine pharmacology indicated that thioguanine (TG) might be more effective than mercaptopurine (MP). The US and UK cooperative groups began randomised thiopurine trials and agreed prospectively to a meta-analysis. All randomised trials of TG versus MP were sought, and data on individual patients were analysed by standard methods. Combining three trials (from US, UK and Germany), the overall event-free survival (EFS) was not significantly improved with TG (odds ratio (OR)=0.89; 95% confidence interval 0.78-1.03). Apparent differences in results between trials may be partly explained by the different types of patients studied. The larger treatment effect reported in males in the US trial was confirmed in the other trials. There was heterogeneity between sex/age subgroups (P=0.001), with significant EFS benefit of TG only observed for males aged <10 years old (OR=0.70; 0.58-0.84), although this did not result in a significant difference in overall survival (OR=0.83; 0.62-1.10). Additional toxicity occurs with TG. Mercaptopurine remains the standard thiopurine of choice, but further study of TG may be warranted to determine whether it could benefit particular subgroups.

Interleukin-1 accelerates murine granulocyte recovery following treatment with cyclophosphamide.

This study investigated the effects of recombinant human interleukin-1 (rhIL-1 alpha) on granulocyte recovery following treatment of mice with cyclophosphamide (CPM). CF1 mice were injected with 0.5 microgram rhIL-1 alpha or heat-inactivated rhIL-1 alpha according to five different regimens, before and/or following 200 mg/kg CPM. Significant neutrophilia initially developed in treatment mice of all five regimens and accelerated granulocyte recovery occurred in treatment mice of four IL-1 regimens. Significant elevations in serum colony stimulating activity (CSA) occurred in treatment mice at a number of time points studied. In addition, marked increases in the percentage of maturing granulocyte precursors and in the proportion of cells cycling in S and G2/M were observed in treatment marrow throughout the IL-1 regimen. Before granulocyte recovery, premature nuclear segmentation was noted in metamyelocytes of treatment marrow. Concomitant with granulocyte recovery, treatment marrow was significantly more cellular and contained more total CFU-GM, more CFU-GM in S phase, more cells in S and G2/M, and more mitotic figures than control marrow. Splenic myelopoiesis was also enhanced in treatment mice. These data suggest that IL-1 significantly hastens granulocyte recovery following treatment with CPM by enhancing both proliferation and maturation of myeloid precursors.

Immunodiffusion and immunohistochemical investigations on the reactivity of oxide ceramic middle-ear implants.

Oxide ceramic materials (partial and total ossicular replacement prostheses) have been implants of preference for the reconstruction of the ossicular chain because of their excellent biocompatibility. The reaction on the surface of the implants takes place at three biodynamic levels according to the model of Stern's bilayer. We investigated the adsorption of proteins, which is determined by the cellular reaction and degradation to the surface using radial immunodiffusion and immunohistochemical methods. First, ceramic implants of aluminum oxide, hydroxyapatite, glass ceramic and zirconium oxide have individual actual (i.e. biological) surfaces. With a perthometer and the contact-free laser Focodyn method we determined each actual (i.e. biological) surface of the various ceramic implants mentioned above. Using radial immunodiffusion, the adsorption of albumin, glycoprotein, plasminogen, fibronectin, IgA, IgG and IgM shows characteristic rates of adsorption to the respective ceramic surfaces in correlating to the actual surface. A cross-check with fluorescent antibodies confirmed the protein adsorption. The individual surface adsorption of the proteins remains characteristic and is the basis for the recording of cellular reactions after implantation.

Cessation of antibiotics regardless of ANC is safe in children with febrile neutropenia. A preliminary prospective trial.

PURPOSE: This study was designed to evaluate the safety and efficacy of stopping antibiotic treatment regardless of absolute neutrophil count (ANC) or signs of impending neutrophil recovery in children with febrile neutropenia (FN) and no identifiable infectious source. PATIENTS AND METHODS: Thirty-two consecutive cases of FN without identifiable source were prospectively evaluated. Patients were examined, cultured, and initially treated with ceftazidime +/- vancomycin. Antibiotics were discontinued and patients discharged regardless of ANC (WBC/microliter x [% segs + bands]) once all the following criteria were met: afebrile > or = 24 h; cultures negative at 48 h; thermometer and telephone available at home. Prompt notification of fever (T > 38.3 degrees C) and readmission were required. RESULTS: Median ANC was 60/microliters on admission and 160/microliters at discharge. Median length of treatment was 3 days. Four patients were readmitted for FN, and two patients were readmitted afebrile for cultures which became positive after discharge. None of the 32 cases suffered apparent complications from early discharge. CONCLUSION: Results of this preliminary trial suggest that cessation of antibiotics regardless of ANC is safe in cases of FN without identifiable source, provided that marrow is not infiltrated and that recurrent fever receives prompt antibiotic retreatment.

Increased activity of the respiratory burst in cord blood neutrophils: kinetics of the NADPH oxidase enzyme system in subcellular fractions.

Previous studies with neutrophils from newborn infants compared to neutrophils from healthy adults have documented increased respiratory burst activity including enhanced superoxide anion (O2-) production, nitroblue tetrazolium dye reduction, and hexose monophosphate shunt activity. To investigate the biochemical basis for these observations, we examined oxidative metabolism in membrane-rich fractions of neutrophils. Neutrophils from cord blood of vaginally delivered term infants or healthy adults were disrupted by nitrogen cavitation and subcellular fractions collected on discontinuous sucrose density gradients. Subcellular fractions of newborn neutrophils separated in a fashion identical with samples from healthy adults. Activity of alkaline phosphatase, a plasma membrane marker, was increased 4- to 5-fold in disrupted cells free from nuclei (postnuclear supernatant) as well as plasma membrane fractions from newborn samples compared to those from healthy adults. Content of lactoferrin, a specific granule marker, was decreased in postnuclear supernatants but equivalent in specific granule fractions of newborn cells compared to those from adults. No differences were noted in myeloperoxidase content of postnuclear supernatants or any other subcellular fraction. Plasma membrane fractions from phorbol myristate acetate-stimulated cord blood neutrophils made significantly more O2- than samples from adults (newborn 32.9 +/- 8.1 nmol O2-/min/mg protein mean +/- SEM, n = 3 versus adult 10.8 +/- 4.2, n = 3; p less than 0.05). Plasma membrane-rich fractions were also collected by the technique of differential centrifugation and kinetic parameters of the NADPH-dependent oxidase enzyme(s) were measured for vaginally delivered newborn and adult samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Heterogeneity of acute "undifferentiated" leukemia of childhood: ultrastructural, immunophenotypic, and karyotypic analyses.

The present study was undertaken in an attempt to reclassify the 19 cases of childhood acute undifferentiated leukemia (AUL) diagnosed at our institution during the past 12 years. Based on ultrastructural and immunophenotypic data, seven of the cases were reclassified as lymphoid, nine as myeloid, and three remain unclassifiable. Clinical features, clonal karyotypes, and responses to treatment were also examined. Abnormal clonal karyotypes were found in 16 of 17 cases, including eight cases with translocations, three with monosomy 7 or 7q, and one with numerous complex structural rearrangements. Fourteen patients had greater than 10% French-American-British L2 blasts in bone marrow. Although nine of 15 patients who initially received induction therapy for acute lymphoblastic leukemia (ALL) achieved remission, only one patient is a long-term survivor. Only one of 10 patients who received therapy for acute nonlymphoblastic leukemia during the course of their disease remains a long-term survivor. These data suggest that the majority of cases of AUL can be reclassified as either myeloid or lymphoid leukemias, that AUL is associated with a high frequency of chromosomal abnormalities, and that AUL carries a very poor prognosis.

Solitary renal myofibromatosis: an unusual cause of infantile hypertension.

INTRODUCTION: Renovascular disease accounts for the vast majority of cases of infantile hypertension with complications resulting from umbilical arterial catheterization predominating in the neonatal period and fibrodysplastic lesions of the renal artery predominating outside the neonatal period. We report a previously undescribed cause of renovascular hypertension: solitary renal myofibromatosis. CASE REPORT: A 9-month-old male infant was transported to the intensive care unit at Children's Hospital in Denver, Colorado, for evaluation and treatment of a dilated cardiomyopathy and severe systemic hypertension. The child was full-term with no perinatal problems. Specifically, the child never required umbilical arterial catheterization. He was well until 6 months of age when his parents noted poor weight gain. At 9 months of age, he was evaluated at the referral hospital for failure to thrive. On examination he was noted to have a blood pressure of 170/110 mm Hg, but no other abnormalities. A chest radiograph showed cardiomegaly. Laboratory studies demonstrated normal electrolytes, blood urea nitrogen, and creatinine. However, urinalysis demonstrated 4+ protein without red blood cells. An echocardiogram showed severe left ventricular dilatation with an ejection fraction of 16%. On admission the child was noted to be cachectic. His vital signs, including blood pressure, were normal for age. The physical examination was unremarkable. Serum electrolytes, blood urea nitrogen, and creatinine were normal. Echocardiographic studies suggested a dilated hypertrophic cardiomyopathy. He was started on digoxin and captopril. Subsequently, he demonstrated episodic hypertension ranging from 170/90 to 220/130 mm Hg. A repeat echocardiogram 24 hours after admission demonstrated a purely hypertrophic cardiomyopathy. Verapamil and nifedipine were added to the treatment regimen in an effort to better control the blood pressure without success. Urine and blood for catecholamines and plasma renin activity, respectively, were sent and treatment with phentolamine instituted because of a possible pheochromocytoma. A spiral abdominal computerized tomographic scan revealed a markedly abnormal right kidney with linear streaky areas of calcification around the hilum and also an area of nonenhancement in the posterior upper pole. The adrenals and the left kidney were normal. Doppler ultrasound revealed a decrease in right renal arterial flow. The urinary catecholamines were normal and surgery was scheduled after the blood pressure was brought under control by medical treatment. At surgery, tumorous tissue and thrombosis of the renal artery were found in the right upper pole. A right nephrectomy was performed. Pathologic examination of the kidney showed the presence of a diffuse spindle cell proliferation in the interstitium of the kidney. The angiogenic/angiocentric character of the proliferation was demonstrated in several large renal vessels. The lumen of most vessels was narrowed and some vessels were totally occluded with recanalization and dystrophic calcifications observed. Immunostaining of the tumor demonstrated strong desmin and vimentin positivity and minimal actin positivity in the spindle cells. Mitotic activity was not noted in the spindle cell process. These pathologic changes were consistent with a diagnosis of infantile myofibromatosis (IM). The child's preoperative plasma renin activity was 50 712 ng/dL/h (reference range, 235-3700 ng/dL/h). DISCUSSION: The causes of systemic hypertension in infancy are many although renal causes are by far the most common. Renal arterial stenosis or thrombosis accounts for 10% to 24% of cases of infantile hypertension. Renal artery thrombosis is usually a consequence of umbilical arterial catheterization, which can also lead to embolization of the renal artery. Renal artery stenosis may result from fibrodysplastic lesions (74%), abdominal aortitis (9%), a complication of renal transplantation (5%), and ren

Pancytopenia in propionic acidemia: hematologic evaluation and studies of hematopoiesis in vitro.

This study investigated the hematologic abnormalities of an infant with propionic acidemia and reversible pancytopenia. Light and electron microscopy of her bone marrow revealed severely disturbed cellular morphology with trilineage dysmyelopoiesis, hemophagocytosis, and numerous multinucleated histiocytes and megakaryocytes. The effects of her serum and of organic acids associated with propionic acidemia were studied on hematopoiesis in vitro. Mouse erythroid (CFU-E) and granulocyte-monocyte colonies (CFU-GM) were assayed by fibrin clot technique; human CFU-GM were grown in agar culture. The infant's serum reduced mouse CFU-E and CFU-GM by 43 and 32%, respectively, compared with normal human sera, but had no effect on human CFU-GM in our culture system. Buffered propionic acid caused concentration-dependent inhibition of mouse CFU-E and human CFU-GM over a range reported in sera of acutely ill infants with propionic acidemia. Neither cell viability nor subsequent colony formation was diminished by preincubation of bone marrow cells with propionic acid for 48 h. The three other organic acids studied, tiglic acid, 3-OH propionate, and glycine, did not inhibit growth of mouse CFU-E, CFU-GM, or human CFU-GM, and glycine significantly enhanced formation of the latter. Evaluation of the infant's hematologic abnormalities suggests that inhibition of bone marrow proliferation and maturation and, perhaps, shortened red blood cell survival were responsible for her pancytopenia. The studies performed in vitro implicate propionic acid in this hematopoietic dysfunction.