Frequency of medium-chain acyl-CoA dehydrogenase deficiency G-985 mutation in sudden infant death syndrome

A small percentage of apparent sudden infant death syndrome (SIDS) victims may have an unsuspected metabolic disorder. Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a disorder of fatty acid oxidation that has been the most common such metabolic disorder found in series of SIDS victims. A single mutation in MCAD deficiency has been recently described (G-985) that accounts for approximately 90% of MCAD deficiency mutations. We studied the hypothesis that heterozygosity or homozygosity for this specific MCAD deficiency mutation might be associated with SIDS. DNA was extracted from the paraffin-embedded autopsy tissues of 67 victims of SIDS in Monroe County, NY who died between 1984 and 1989. Using the polymerase chain reaction/NcoI digestion method, we found no G-985 homozygotes and three (4.5%) G-985 heterozygotes. In 70 newborn controls, there were no G-985 homozygotes and one (1.4%) heterozygote. Although the frequency of G-985 heterozygotes was slightly greater than in our control group, it was not statistically different. We conclude that the specific MCAD deficiency mutation G-985 is not strongly associated with SIDS and that MCAD deficiency probably does not make a significant contribution to the etiology of SIDS.

Differences across sexual orientation on HIV risk behaviours in injecting drug users

Injecting drug users (IDUs) play a disproportionate role in the spread of HIV given their injecting and sexual contacts, and thereby act as conduits between these risk groups. We investigated differences in risk behaviour and HIV seroprevalence in a Sydney sample of 1,245 IDUs. Significant differences were observed across sexual orientation in HIV serostatus for males, with homosexual men having the highest HIV seroprevalence rate (35%), bisexual men intermediate (12%) and heterosexual men lowest (3%). Sexual HIV risk behaviours were lowest for homosexual men, intermediate for bisexual men, and highest for heterosexual men in the case of condom use: however, for numbers of partners, seroprevalence, and anal sex the trends were reversed. There were no differences across sexual orientation for either sex for injecting drug risk behaviours. Both male and female respondents reported having more than 50% of sexual contacts while under the influence of drugs. This study suggests that risk reduction in the sexual domain has not generalized to the injecting risk domain regardless of sexual orientation, and demonstrates that sexual risk behaviours in IDUs are lowest in homosexual, intermediate in bisexual, and highest in heterosexual IDU men.

An infant with trisomy 9 mosaicism presenting as a complete trisomy 9 by amniocentesis

We present a case in which amniocentesis performed at 33 weeks' gestation because of symmetrical intrauterine growth retardation and decreased amniotic fluid volume led to the prenatal diagnosis of a fetus with a karyotype of 47,XX,+9,t(1;20)(q42;p11.2) pat, i.e., with an extra chromosome 9 and a balanced translocation between chromosomes 1 and 20. At delivery, the baby showed clinical features of trisomy 9, yet chromosome analysis of the cord blood revealed no trisomy 9 cells, a finding confirmed by neonatal blood karyotyping. The balanced translocation was present in all cells. A skin biopsy confirmed trisomy 9 mosaicism with 10 per cent trisomy 9 cells. The baby died at 6 weeks and an autopsy was obtained. Chromosome analysis of different organs demonstrated different frequencies of the mosaicism of trisomy 9. The possible underlying mechanism for the discrepancy between the karyotype results by amniocentesis and those of other tissues is discussed.

Medicare hospital outpatient services and costs: implications for prospective payment

Medicare expenditures of hospital outpatient department (HOPD) services are growing rapidly, prompting congressional interest in a prospective payment system. In this article, the authors identify frequently provided services and examine service volume and charges in the HOPD. Relatively few services drive Medicare HOPD spending, and volume is dominated by visits, imaging and laboratory tests, whereas surgery accounts for a large proportion of charges. Hospital-level variations in charges, costs, case mix, and outliers are also explored. There is substantial variation in charges and costs across hospital types. However, after case-mix adjustment, all hospital types have average costs within 6 percent of the national average.

Phase II trial of high-dose cisplatin plus etoposide plus vinblastine in non-small-cell lung cancer. A Hoosier Oncology Group study

Fifty-one patients with advanced non-small-cell lung cancer were treated on a Hoosier Oncology Group protocol with an aggressive, high-dose cisplatin combination chemotherapy regimen. All patients had a Karnofsky performance status of 80% or higher and had no prior chemotherapy. The drug regimen consisted of cisplatin 30 mg/m2 days one through five, etoposide 40 mg/m2 days one through five, and vinblastine 5 mg/m2 day one. Therapy was given every three weeks for a total of three courses. Forty-five patients were evaluable for response and an objective response was seen in 15 patients (33%) with only one complete responder. The median duration of response was 16.5 weeks. The median survival for the entire group was 29.0 weeks. Toxicity was moderately severe with two treatment-related deaths (4%). Despite an aggressive chemotherapy regimen in a favorable patient population, there was no obvious evidence of a major therapeutic value.

Scapular fractures. Analysis of 113 cases

Scapular fractures have been the subject of study since Desault's treatise of 1805, but few large-scale studies have been completed with long-term follow-up evaluation of displaced scapular neck and spine fractures. This series of 148 fractures in 116 scapulae (113 patients) appears to be the largest ever reported and the only one with a follow-up study of a significant group (24 patients). Significant disability was found in patients with displaced scapular spine and neck fractures: (1) pain at rest in 50%-100%, (2) weakness with exertion in 40%-60%, and (3) pain with exertion in 20%-66%. Based on these findings, the indications for operative management should be expanded to include displaced scapular neck and spine fractures. Using extensile exposure through a posterior Judet incision, rigid internal fixation, and early motion, results in eight cases were excellent. All patients recovered at least 85 degrees of glenohumeral abduction, normal scapulothoracic motion, and none had resting pain, night pain, or pain with abduction. The minimum follow-up study period was 15 months.

Validation techniques for logistic regression models

This paper presents a comprehensive approach to the validation of logistic prediction models. It reviews measures of overall goodness-of-fit, and indices of calibration and refinement. Using a model-based approach developed by Cox, we adapt logistic regression diagnostic techniques for use in model validation. This allows identification of problematic predictor variables in the prediction model as well as influential observations in the validation data that adversely affect the fit of the model. In appropriate situations, recommendations are made for correction of models that provide poor fit.

Practice randomization and clinical research. The Indiana experience

Thoughtful preparation of a research laboratory is an early step in designing a program for scientific investigation. The Division of General Internal Medicine at Indiana University has maintained a "laboratory" for outpatient clinical investigation for more than 15 years. In this report, we describe the structure and function of the General Medicine Practice in the Regenstrief Health Center on the campus of the Indiana University School of Medicine in Indianapolis. Specifically, we discuss the ongoing random allocation of subjects, the local resources for data management and tracking of patients' use of clinical services, and how combining this information system into a randomized primary care system has fostered successful ventures in clinical investigation.

Randomized study of cisplatin dose intensity in poor-risk germ cell tumors: a Southeastern Cancer Study Group and Southwest Oncology Group protocol

Between 1984 and 1989, 159 patients presenting with advanced germ cell cancer were entered on a randomized clinical trial comparing the efficacy and toxicity of etoposide and bleomycin and either standard-dose cisplatin (20 mg/m2 daily for 5 days) or high-dose cisplatin (40 mg/m2 daily for 5 days). Of the 159 patients, 153 were assessable for toxicity and response. As expected, patients receiving the high-dose cisplatin regimen experienced significantly more neurotoxicity, ototoxicity, nausea and vomiting, and myelo-suppression. Four patients (3%) died related to therapy. Despite the toxicity encountered, dose intensity was maintained. Overall, 84% of patients in the high-dose arm received 80% or more of the projected dose of cisplatin, etoposide, and bleomycin; and 90% of patients on the standard-dose arm received 80% or more of the projected dose. Of the 76 eligible patients randomized to receive the high-dose cisplatin regimen, 52 (68%) became disease-free with chemotherapy alone or with subsequent resection of residual teratoma or cancer. Of the 77 patients randomized to the standard-dose arm, 56 (73%) became disease-free with chemotherapy alone or with surgery. Median follow-up is now 24 months. Eleven patients (three high-dose and eight standard-dose) relapsed from disease-free status. Overall, 74% of patients receiving the high-dose cisplatin regimen are alive, and 63% are continuously free of disease. Of the patients receiving the standard-dose cisplatin regimen, 74% are alive, and 61% are continuously free of disease. This randomized prospective trial in advanced germ cell cancer achieved dose intensity of the most active single agent in this disease. This dose intensity did not translate into an improved survival or cure. We conclude that dose escalation of cisplatin beyond standard doses results in excess toxicity with no accompanying therapeutic benefit.

Generalized variance component models for clustered categorical response variables

A generalized variance component model is proposed for the analysis of a categorical response variable with extra-multinomial variation. Categorical data obtained from research designs such as randomized multicenter clinical trials or complex sample surveys with clustering frequently exhibit extra-variation resulting from intracluster correlation. General correlation patterns are accounted for by utilizing a mixed-effects modelling approach, estimating the cluster variance components through the method of moments and modelling functions of the observed proportions through the use of estimating equations. A flexible set of assumptions characterizing the underlying covariance structure for the proportions can be accommodated. The importance of accounting for extra-variation when performing hypothesis tests is highlighted with an application to data from a multi-investigator clinical trial.

A herald bleed: a case of aortoesophageal fistula and a review of the literature

Survival in AEF is rare because the diagnosis of this uncommon entity is not always suspected, and few patients survive despite aggressive but often late intervention. We present this case to increase awareness of AEF, which although rare, does occur and should be suspected in any patient who presents with midthoracic pain or dysphagia and herald bleeding.

Sexually transmissible diseases in injecting drug users

Self-reported histories of sexually transmissible diseases (STDs) and HIV serostatus were investigated as part of a study of HIV risk behaviour in a sample of 1245 Syndey injecting drug users (IDUs) (mean age 27.5 years) both in and out of treatment. A high lifetime prevalence of STDs was reported in both men and women. For male IDUs, the lowest reported lifetime prevalence of STDs was in heterosexuals, with bisexuals intermediate and homosexuals reporting the highest prevalence. HIV seroprevalence followed the same pattern. For women, bisexuals had the highest reported STD history, heterosexual women were intermediate and homosexual women reported the lowest prevalence. Over one third of the bisexual women reported having been involved in prostitution. These data indicate that over one third of IDU men and over half of IDU women reported at least one STD in their lifetime. The high lifetime prevalence of STDs in IDUs indicates that this group is at increased risk of sexual transmission of HIV, given the importance of STDs as a cofactor. Reducing the prevalence of STDs in IDUs is a possible additional strategy to diminish the spread of HIV among IDUs and from them to non-IDU sexual contacts.

Megaloblastic hematopoiesis in vitro. Interaction of anti-folate receptor antibodies with hematopoietic progenitor cells leads to a proliferative response independent of megaloblastic changes

We tested the hypothesis that anti-placental folate receptor (PFR) antiserum-mediated effects on hematopoietic progenitor cells in vitro of increased cell proliferation and megaloblastic morphology were independent responses. We determined that (a) purified IgG from anti-PFR antiserum reacted with purified apo- and holo-PFR and specifically immunoprecipitated a single (44-kD) iodinated moiety on cell surfaces of low density mononuclear cells (LDMNC); (b) when retained in culture during in vitro hematopoiesis, anti-PFR IgG (in contrast to PFR-neutralized anti-PFR IgG and nonimmune IgG) consistently led to increased cloning efficiency of colony forming unit-erythroid (CFU-E), burst forming unit-E (BFU-E), CFU-granulocyte macrophage (CFU-GM), and CFU-GEM megakaryocyte (CFU-GEMM), and objectively defined megaloblastic changes in orthochromatic normoblasts from CFU-E- and BFU-E-derived colonies; (c) when anti-PFR antiserum was removed after initial (less than 1 h) incubation with LDMNC, a cell proliferation response was induced, but megaloblastic changes were not evident. (d) Conversely, delay at 4 degrees C for 24 h before long-term plating with antiserum resulted in megaloblastosis without increased cell proliferation; (e) however, 500-fold molar excess extracellular folate concentrations completely abrogated the expected anti-PFR antiserum-induced megaloblastic changes, without altering cell proliferative responses. Thus, although cell proliferative and megaloblastic changes are induced after short-term and prolonged interaction of antibody with folate receptors on hematopoietic progenitors, respectively, they are independent effects.

Dorsal dislocation of the trapezoid

A case of dorsal dislocation of the trapezoid associated with dorsal subluxation of the carpometacarpal joints of the index and long fingers is described. The initial trapezoid subluxation was overlooked and it progressed quickly to a complete dislocation. Open reduction and capsular repair without internal fixation was followed by early recurrent trapezoid subluxation. Repeat open reduction combined with a limited intercarpal arthrodesis was used as a salvage procedure and produced a good result.

Normalization of plasma arginine vasopressin concentrations when children with meningitis are given maintenance plus replacement fluid therapy

We hypothesized that plasma arginine vasopressin (AVP) concentrations in children with meningitis are appropriate for the children's degree of hypovolemia, even though the concentrations were higher than expected for the serum osmolality. A randomized study was conducted to compare the effect on plasma AVP concentrations of giving maintenance fluid requirements plus replacement of any deficit versus restricting fluids to two thirds of maintenance requirements for 24 hours. Plasma AVP concentrations and serum osmolality were measured before fluid therapy was begun and again after 24 hours. Nineteen children, 2 months to 17 years of age, were studied; 13 had bacterial meningitis (12 with Haemophilus influenzae type b). Ten children (seven with bacterial meningitis) received a mean of 1.42 times the calculated maintenance fluid requirements, and nine (six with bacterial meningitis) were restricted to a mean of 0.65 times maintenance. Children in the maintenance group also received significantly more sodium (mean = 6.3 mEq/kg/24 hr) than children in the fluid-restricted group (mean = 2.0 mEq/kg/24 hr). The two groups were comparable for plasma AVP concentration and serum osmolality before fluid therapy was begun. The plasma AVP concentration was significantly lower after 24 hours of maintenance plus replacement fluids than after fluid restriction (p = 0.005), and the change in AVP concentration correlated with the amount of sodium given (p less than 0.02). This study supports the hypothesis that serum AVP concentrations are elevated in patients with meningitis because of hypovolemia and become normal when sufficient sodium is given to facilitate reabsorption of water by the proximal tubule of the kidney. Patients with meningitis can be given maintenance plus replacement fluids but should be monitored for the development of the syndrome of inappropriate secretion of antidiuretic hormone.

Characteristics of engraftment after repeated autologous bone marrow transplantation

The rate of engraftment after autologous bone marrow transplantation (ABMT) is extremely variable and largely unpredictable. To identify factors influencing engraftment, we studied 35 patients with refractory germ cell tumors undergoing high-dose chemotherapy with carboplatin (900-2000 mg/m2) and etoposide (1200 mg/m2) with bone marrow rescue. Prior to the initiation of chemotherapy, bone marrow sufficient for two marrow infusions was harvested (range 0.86-4.82 x 10(8) nucleated cells per kg). All 35 patients received half of the collected bone marrow 3 days after the last dose of chemotherapy; 23 responders received a second round of the same chemotherapy followed by infusion of the second half of the bone marrow. Eighteen patients could be compared for the two transplant episodes. The "rate of engraftment" was defined as the unweighted mean of four parameters: 1) the number of days until the absolute granulocyte count surpassed 0.2 x 10(9)/liter, 2) the number of days until the absolute granulocyte count surpassed 0.5 x 10(9)/liter, 3) the number of days until the last platelet transfusion, and 4) the number of days until the reticulocyte count surpassed 25 x 10(9)/liter. No significant correlation was found between rate of engraftment and such factors as the number of nucleated cells per kg infused, the dose of chemotherapy, extent of prior chemotherapy, tumor response to the high-dose chemotherapy, age of the patient, or the days of granulocytopenic fever (all p greater than 0.20). In contrast, a close correlation was found for the number of units of platelets (p = 0.005) and red blood cells (p = 0.006) transfused following each of the two transplants. There was no significant difference between rate of engraftment after first and second transplantation. Comparison of these data with the results obtained in reported ABMT with separate harvests suggests that the characteristics of the infused marrow determine the rate of engraftment after ABMT. This model of repeated transplantation could provide an important tool for assessing the therapeutic efficacy of hematopoietic growth factors.

Enhanced stimulation of human bone marrow macrophage colony formation in vitro by recombinant human macrophage colony-stimulating factor in agarose medium and at low oxygen tension

Recombinant (r) and natural human (h) macrophage colony-stimulating factor (M-CSF, CSF-1) have been considered poor stimulators of macrophage progenitor cells present in human marrow, although they are potent stimulators of these cells in mouse marrow. We compared the growth characteristics of rhM-CSF-responsive human macrophage progenitor cells placed in semisolid agarose or agar culture medium and incubated for 14 days at ambient (approximately 20%) or lowered (5%) O2 tension. By itself, rhM-CSF was found to be a good stimulator of macrophage colony formation by human bone marrow cells cultured in agarose but not in agar; this growth was enhanced by incubation at 5% O2. Maximal numbers (up to 115/10(5) nonadherent low density cells plated) of macrophage colonies (50 to greater than 500 cells per colony) were stimulated by 500 to 1,000 units rhM-CSF/mL, with 1/2 maximal numbers stimulated by 250 to 500 units/mL. With agarose as the support medium, rhM-CSF was two- to fourfold more active on mouse than on human macrophage colony formation, in contrast to previous reports of 10- to 100-fold greater activity when agar was used as the support medium. Using nonadherent low density T lymphocyte-depleted human bone marrow cells growing in agarose at 5% O2, greater than additive effects on colony formation were observed when 31 to 500 units rhM-CSF were used in combination with either 10 ng rh interleukin-1 alpha (IL-1 alpha), 20, or 200 units rh granulocyte-macrophage (GM)-CSF or rhG-CSF. The agarose assay system should be useful for evaluating factors regulating the proliferation of human macrophage progenitor cells in vitro and during clinical trials with rhM-CSF.

The effect on test ordering of informing physicians of the charges for outpatient diagnostic tests

We studied the effect of informing physicians of the charges for outpatient diagnostic tests on their ordering of such tests in an academic primary care medical practice. All tests were ordered at microcomputer workstations by 121 physicians. For half (the intervention group), the charge for the test being ordered and the total charge for tests for that patient on that day were displayed on the computer screen. The remaining physicians (control group) also used the computers but received no message about charges. The primary outcomes measured were the number of tests ordered and the charges for tests per patient visit. In the 14 weeks before the study, the number of tests ordered and the average charge for tests per patient visit were similar for the intervention and control groups. During the 26-week intervention period, the physicians in the intervention group ordered 14 percent fewer tests per patient visit than did those in the control group (P less than 0.005), and the charges for tests were 13 percent ($6.68 per visit) lower (P less than 0.05). The differences were greater for scheduled visits (17 percent fewer tests and 15 percent lower charges for the intervention group; P less than 0.01) than for unscheduled (urgent) visits (11 percent fewer tests and 10 percent lower charges; P greater than 0.3). During the 19 weeks after the intervention ended, the number of tests ordered by the physicians in the intervention group was only 7.7 percent lower than the number ordered by the physicians in the control group, and the charges for tests were only 3.5 percent lower (P greater than 0.3). Three measures of possible adverse outcomes--number of hospitalizations, emergency room visits, and outpatient visits during the study period and the following six months--were similar for the patients seen by the physicians in both groups. We conclude that displaying the charges for diagnostic tests significantly reduced the number and cost of tests ordered, especially for patients with scheduled visits. The effects of this intervention did not persist after it was discontinued.

Primary mediastinal nonseminomatous germ cell tumors. A modern single institution experience

Between 1976 and 1988, 31 patients with mediastinal nonseminomatous germ cell tumors (MNGCT) received initial cisplatin-based chemotherapy of uniform intensity. Eighteen of these patients (58%) obtained disease-free status; 11 with chemotherapy alone and seven with adjunctive surgery. Eleven have remained continuously free of disease. Two have had recurrence of teratoma and are disease-free after resection of teratoma at 12+ and 68+ months. Three patients developed recurrence of germ cell tumor. Three patients developed a hematologic malignancy. Of the 18 patients who obtained disease-free status, 15 remain alive and disease-free. Overall, 13 of the 31 patients and 24 other patients received salvage chemotherapy at Indiana University, Indianapolis, Indiana. Of these 37 patients, six obtained a disease-free status and four (11%) remain alive at 13+, 56+, 78+, and 122+ months, respectively. This series represents the largest series of patients with MNGCT ever reported. Analysis of these data and results from other recent series suggest that approximately 50% of patients with MNGCT will be cured with modern, intense cisplatin-based chemotherapy coupled with adjunctive surgery if needed.

Effect of omental, intercostal, and internal mammary artery pedicle wraps on bronchial healing

Bronchial transection and devascularization is necessary in the course of sleeve resection or lung transplantation, leaving distal bronchial segments ischemic and subject to stricture or dehiscence. Thirty mongrel dogs underwent left lung autotransplantation. The bronchial anastomosis was wrapped with omentum (n = 9), intercostal muscle pedicle (n = 9), or internal mammary artery pedicle grafts (n = 6). Six control animals underwent bronchial anastomosis without an external wrap. Bronchial revascularization by capillary ingrowth from the pedicle to the bronchial submucosal plexus was demonstrated with all three types of vascular pedicle grafts; however, more consistent and confluent vascular ingrowth was provided by internal mammary artery pedicle grafts. Additionally, the bronchial anastomotic cross-sectional area was significantly better in the internal mammary artery group (84.5 +/- 3.3) as compared with that of the omental (68.4 +/- 8.3), intercostal muscle (66.9 +/- 10.9), or control groups (70.2 +/- 7.6). An internal mammary artery pedicle graft and the presence of dense confluent submucosal vascular ingrowth from any pedicle graft were independently predictive (p less than 0.05) of minimizing bronchial anastomotic narrowing. These data are consistent with previous findings suggesting that omental and intercostal muscle pedicle grafts promote early bronchial revascularization; moreover, the data demonstrate the superiority of an internal mammary artery pedicle graft to provide submucosal vascular ingrowth and to minimize anastomotic stenosis.

Is prophylactic cranial irradiation indicated in small-cell lung cancer?

Although prophylactic cranial irradiation (PCI) is frequently used in the treatment of patients with limited-extent small-cell lung cancer (SCLC), its role remains controversial. One hundred fourteen SCLC patients with limited disease treated at Indiana University were retrospectively reviewed. Fifty-eight of 114 (51%) patients achieved a complete remission (CR) and were analyzed. Thirty-eight of these 58 CR patients received PCI (+PCI) and 20 of 58 CR patients did not receive PCI (-PCI). Twenty-six of 38 patients who received PCI subsequently relapsed. No patient initially relapsed in the CNS, although one patient had a brain metastasis following recurrence in the chest. Eleven of 38 patients who were treated with PCI survived for longer than 30 months and were considered long-term survivors. Seven of these 11 patients (63%) developed clinically significant neurological toxicity. Sixteen of 20 patients who did not receive PCI relapsed, but there was only one initial relapse in the CNS. Three additional patients who relapsed in the chest subsequently developed CNS metastasis. All responded to palliative radiation with improvement in their symptoms. The high incidence of CNS toxicity in the long-term survivors and the relatively infrequent incidence of isolated CNS recurrent in patients not subjected to PCI raise serious questions concerning the role, if any, of PCI in limited SCLC.