Diagnostic criteria and prognosis in polycythemia vera and essential thrombocythemia

Polycythemia vera (PV) and essential thrombocythemia (ET) are two myeloproliferative disorders (MPDs) that result from an acquired mutation of a single hematopoietic stem cell that gives the progeny of the stem cell a growth advantage over their normal counterparts. The incidence of both diseases appears to be similar. From time to time, PV has an atypical presentation making it difficult to differentiate from ET and other MPDs. Identification of a patient as having PV or ET generally follows the observation of elevated hematocrit or elevated platelet count. Thrombotic complications are the major cause of morbidity and mortality in both groups of patients. In PV, the frequencies of venous and arterial thrombosis are about equal, whereas venous thrombosis is less common in ET. Accurate diagnosis of these disorders is essential for proper treatment. The prognosis for untreated, asymptomatic ET patients is generally good, but quite poor for untreated PV patients. Proper treatments have been shown to reduce complications and significantly extend the life span for both groups of patients.

Transmission electron microscopy studies of Moraxella (Branhamella) catarrhalis

A trypsin-sensitive 200-kDa protein has been reported to be exclusively associated with haemagglutinating isolates of Moraxella (Branhamella) catarrhalis. Transmission electron microscopy studies revealed that haemagglutination by M. catarrhalis to both human and rabbit erythrocytes was mediated by a trypsin-sensitive outer fibrillar coat. This fibrillar layer was absent on non-haemagglutinating isolates examined. Immuno-electron microscopy, using a polyclonal antiserum containing antibodies to the 200-kDa protein as a probe, showed that the 200-kDa protein is present on the outer fibrillar layer of the bacterium. These findings suggest that the haemagglutinin of M. catarrhalis is a 200-kDa protein present on the outer fibrillar coat.

Provision of HPA-1a (PlA1)-negative platelets for neonatal alloimmune thrombocytopenia: screening, testing, and transfusion protocol

HPA-1a-negative platelet products are not routinely available for newborns with alloimmune thrombocytopenia. In this article we describe a program established to identify normal pheresis donors who are HPA-1a-negative and to organize their future donations so that our regional blood center would always have an HPA-1a-negative platelet product available. The solid phase red cell adherence assay was used for initial screening of platelet pheresis products. HPA-1a-negative donors were confirmed with the platelet suspension immunofluorescence test using three anti-HPA-1a sera. Screening of 2600 plateletpheresis donor samples identified 40 HPA-1a-negative donors. Of these, 36 are active and are coded for recognition on the daily pheresis inventory sheet. Theoretically, assuming four donations per year and donors' cooperation with scheduling, these 36 donors would enable us to have at least one HPA-1a-negative product available every day. In addition, a decision tree for patient management using platelet serology and availability of HPA-1a-negative products was developed. The GTI-PAK trade mark 12 is the major technique used for serologic screening of mothers of patients thought to have neonatal alloimmune thrombocytopenia. By screening pheresis donors and developing a clinical decision tree, HPA-1a-negative products, a rare resource, can be fully utilized.

High incidence of the Cys 282 Tyr mutation in the HFE gene in the Irish population--implications for haemochromatosis

A simple PCR-SSOP approach based on a single PCR product has been developed to screen the HFE gene for the haemochromatosis-associated mutations Cys 282 Tyr and His 63 Asp. Using this approach the prevalence of these mutations in a cohort (30) of haemochromatosis patients and normal controls (404) was determined. Ninety percent of the haemochromatosis patients were homozygous for the Cys 282 Tyr mutation. In the normal population we found an increased incidence of the Cys 282 Tyr mutation (17.3%; 95% confidence limits 0.136-0.209) which was also reflected in the higher frequency of Cys 282 Tyr homozygotes (1.24%; 95% confidence limits 0.0016-0.0232). Linkage disequilibrium analysis confirmed the association between A*03 and Cys 282 Tyr. However, strong linkage disequilibrium occurred with the HLA-A*03-associated allele HLA-B*14 but not the HLA-A*03-associated allele HLA-B*07. The His 63 Asp was found to be in linkage disequilibrium with HLA-A*29.

Does new technology increase or decrease health care costs? The treatment of peptic ulceration

OBJECTIVES

To determine whether new technology increases or decreases formal health care costs, with reference to the diagnosis and treatment of peptic ulcers.

METHODS

A costing method has been devised which is designed to investigate directly the way in which the costs to formal health services of diagnosing and treating an individual illness have changed with changes in technology.

RESULTS

The cost of diagnosis has increased almost entirely as a result of the high cost of endoscopy compared with X-ray examination. The introduction of H2-receptor antagonist drugs increased the cost of treatment compared with the earlier phases of surgical treatment. Subsequently, Helicobacter pylori eradication treatment has reduced the cost of treatment compared with all earlier phases of technology.

CONCLUSIONS

A method has been devised that allows the impact of changes in medical technology on formal health care costs to be investigated for individual illnesses. In the treatment of peptic ulceration, the current technology, H. pylori eradication, has lower treatment costs than all previous technologies. The evidence from previous studies and this study is insufficient to support the assertion that new technology in general leads either to an increase or to a decrease in health care costs.

The natural history of asthma

Our understanding of the natural history of asthma is improving through the establishment of a more precise definition of asthma linked with information from large-scale longitudinal studies. Risk factors for the development of childhood asthma including sex, atopic status, genetic and familial factors, respiratory infections, and outdoor and indoor pollution are now more clearly understood. New information on the relation of viral wheezing episodes in infancy to later childhood asthma is evolving. We now know that children who start wheezing early in life and continue to wheeze at age 6 years are more likely to have a maternal history of asthma, elevated serum IgE levels, and normal lung function in the first year of life. However, at age 6 years they have both elevated serum IgE levels and diminished lung function. Approximately 50% of adults who report having had childhood asthma no longer have symptoms. Airway responsiveness in childhood tends to predict airway responsiveness in adulthood and to be greater in asthmatics with persistent symptoms. Studies of the natural history of asthma support the hypothesis that early therapeutic intervention in mild disease may lead to an improved clinical outcome. Adults exposed to specific occupational environments are at additional risk for the development of asthma. As we learn more about the natural history of asthma, we will have a better understanding of the effect of early diagnosis, environmental control, and therapy on the outcome of the disease.

Exposure to duty-related incident stressors in urban firefighters and paramedics

Little is known about the variables that might be associated with posttraumatic stress symptomatology in high-risk occupational groups such as professional firefighters and paramedics. A sample of 173 urban professional firefighter/EMT's and firefighter/paramedics rated and ranked the stressfulness of 33 actual and/or potential duty-related incident stressors. They also reported whether they had experienced each of these incident stressors within the past 6 months and, if they had, to recall on how many occasions within the past 6 months. A principal components analysis of their rescaled incident stressor ratings yielded five components: Catastrophic Injury to Self or Co-worker, Gruesome Victim Incidents, Render Aid to Seriously Injured, Vulnerable Victims, Minor Injury to Self and Death & Dying Exposure.

Evaluation of the Amicus Separator in the collection of apheresis platelets

BACKGROUND

A new apheresis instrument, the Amicus Separator with software versions 2.13 and 2.34, was evaluated for component yields, collection efficiency, and incidence of donor and transfusion recipient reactions. The Amicus was also compared to the Spectra Leukocyte Reduction System (LRS) with version 5 software.

STUDY DESIGN AND METHODS

Single and double apheresis platelets (APs) were collected at two locations. The targeted platelet yields were 4.0 x 10(11) for single APs and 6.8 x 10(11) for double APs. One location used a double-needle procedure, and the other used a single-needle procedure. Along with 28 of the Amicus procedures (14 at each of two locations), the same donors underwent single or double AP collections on the Spectra LRS. APs were tested for platelet yields and residual white cells. APs were transfused in three hospitals. Donor and transfusion recipient reactions and technical problems were documented.

RESULTS

The Amicus Separator efficiently collected single APs (n = 59) and double APs (n = 62) with mean platelet yields of 4.2 x 10(11) and 6.5 x 10(11), respectively. When inlet line alarms occurred in single-needle procedures, platelet yields were lower and collection times were longer. All APs were white cell-reduced below 5.0 x 10(6), and all but one AP were white cell-reduced below 1.0 x 10(6) without filtration. Component yields from the paired Amicus and Spectra LRS procedures were comparable. Collection times (excluding reinfusion/rinseback) were 20 to 23 minutes faster on the Amicus Separator. No serious donor or transfusion recipient reactions occurred.

CONCLUSION

The Amicus Separator provided satisfactory platelet yields and collection efficiency, with shorter collection times than did the Spectra LRS, and it white cell-reduced components without filtration.

Sexually transmitted disease rates before and after HIV testing

The aim of the study was to evaluate the effect of having an HIV-positive or negative test result on sexual risk behaviour before and after the test. Longitudinal retrospective case-note survey identifying new episodes of sexually transmitted disease (STD) infections in 114 subjects testing HIV positive and 114 matched negatives were examined at the Genitourinary Medicine Department, St Mary's Hospital, Paddington, London. Across the whole sample in the year after HIV testing the number of cases of new STD infections was 40% of the number of cases in the year prior to HIV testing. There was no association between serostatus and incidence of STD infections before and after HIV testing. Of those testing negative, 5.3% were identified as having a new infection in the year after the HIV test, while amongst those testing positive there was a rate of new STDs of 2.6%. In conclusion, there was no evidence that having a negative test result increased the risk of acquisition of new STDs. Rates of new STD infections amongst seropositives in the year after HIV testing were low.

Regional and temporal specialization in the nucleus: a transcriptionally-active nuclear domain rich in PTF, Oct1 and PIKA antigens associates with specific chromosomes early in the cell cycle

PTF (PSE-binding transcription factor) activates transcription of snRNA and related genes. We investigated its distribution in HeLa nuclei by immunofluorescence, and found it spread throughout the nucleoplasm in small foci. In some cells, PTF is also concentrated in one, or very few, discrete regions (diameter approximately 1.3 micron) that appear during G1 phase and disappear in S phase. Oct1, a transcription factor that interacts with PTF, is also enriched in these domains; RNA polymerase II, TBP and Sp1 are also present. Each domain typically contains 2 or 3 transcription 'factories' where Br-UTP is incorporated into nascent transcripts. Accordingly, we have christened this region the Oct1/PTF/transcription (OPT) domain. It colocalizes with some, but not all, PIKA domains. It is distinct from other nuclear domains, including coiled bodies, gemini bodies, PML bodies and the perinucleolar compartment. A small region on chromosome 6 (band 6p21) containing only approximately 30 Mbp DNA, and chromosomes 6 and 7, associate with the domain significantly more than other chromosomes. The domains may act like nucleoli to bring particular genes on specific chromosomes together to a region where the appropriate transcription and processing factors are concentrated, thereby facilitating the expression of those genes.

Excitatory amino acid receptor antagonists decrease hypoxia induced increase in extracellular dopamine in striatum of newborn piglets

The present study tested the hypothesis that the increase in extracellular striatal dopamine during hypoxia is least partly associated with activation of N-methyl-D-aspartate (NMDA) and/or non-NMDA excitatory amino acid receptors. Studies were performed in anesthetized and mechanically ventilated 2-3 days old piglets. Hypoxic insult was induced by decreasing the oxygen fraction in inspired gas (FiO2) from 22 to 7% for 1 h, followed by 1 h reoxygenation at 22%. Cortical oxygen pressure was measured optically by oxygen dependent quenching of phosphorescence, and extracellular striatal dopamine was measured using in vivo microdialysis. The microdialysis probes were perfused with Ringer solution +/- 50 microM (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) or 50 microM 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX). One hour of hypoxia decreased the cortical oxygen pressure from 46 +/- 3 Torr to 10 +/- 1.8 Torr. In striatum perfused with Ringer, statistically significant increase in extracellular dopamine, to 1050 +/- 310% of control, was observed after 20 min of hypoxia. By 40 min of hypoxia the extracellular level of dopamine increased to 4730 +/- 900% of control; by the end of the hypoxic period the values increased to 18,451 +/- 1670% of control. The presence of MK-801 in the perfusate significantly decreased the levels of extracellular dopamine during hypoxia. At 20, 40 and 60 min of hypoxia extracellular level of dopamine increased to 278 +/- 94% of control, 1530 +/- 339% of control and 14,709 +/- 1095 of control, respectively. The presence of NBQX caused a statistically significant decrease, by about 30%, in the extracellular dopamine compared to control, only at the end of the hypoxic period. It can be concluded that in striatum of newborn piglets, the excitatory NMDA receptors but not the non-NMDA receptors may be modulating the changes in extracellular levels of dopamine. The NMDA receptor antagonist, MK-801, may exert part of its reported neuroprotective effect to hypoxic stress in striatum by decreasing the levels of extracellular dopamine.

Risk factors, treatment, and outcome of central nervous system recurrence in adults with intermediate-grade and immunoblastic lymphoma

To evaluate the incidence, risk factors, and outcome of central nervous system (CNS) recurrence in adult patients with non-Hodgkin's lymphoma, we evaluated 605 newly diagnosed patients with large-cell and immunoblastic lymphoma who participated in prospective chemotherapy studies. The Kaplan-Meier estimate of probability of CNS recurrence at 1 year after diagnosis was 4.5% (95% confidence interval [CI], 4.4 to 4.6). Twenty-four patients developed CNS recurrence after a median of 6 months from diagnosis (range, 0 to 44 months). In univariate analysis, an increased risk for CNS recurrence was associated with an advanced disease stage (P = .0014), an increased LDH (P = .0000), the presence of B-symptoms (P = . 0037), involvement of more than one extranodal site (P = .0000), poor performance status (P = .0005), and B-cell phenotype (P = .008). Bone marrow involvement (P = .005), involvement of parenchymal organs (P = .03), and involvement of skin, subcutaneous tissue, and muscle (P = .002) were also associated with an increased risk for CNS disease. Multivariate logistic regression analysis identified only involvement of more than one extranodal site (P = .0005) and an increased LDH (P = .0008) as independent predictors of CNS recurrence. Established CNS recurrence had a poor prognosis. Only 1 of 24 patients remains alive and the Kaplan-Meier estimate of probability of survival at 1 year after the diagnosis of CNS recurrence is only 25.3% (95% CI, 6.9 to 43.7). Intrathecal treatment provided symptomatic benefit in only 1 of 6 patients. Radiation treatment provided symptomatic improvement in 6 of 9 patients treated. However, remissions were short and followed by systemic or CNS recurrence. Serum LDH and involvement of more than one extranodal site are independent risk factors for CNS recurrence in patients with large-cell lymphoma. The presence of both risk factors identifies a patient group at high risk for CNS recurrence. Established CNS recurrence can be rapidly fatal. Transient responses occur after radiation treatment.

Pathogen-free granulomatous diseases of the central nervous system

Pathogen-free granulomatous diseases (PFGD) of the central nervous system (CNS) are a group of disorders with protean clinical and pathological findings. Failure to identify a causative organism leads to considerable diagnostic difficulty. The neuropathology records between 1985 and 1995 were retrospectively reviewed, and the medical records of all patients in whom a diagnosis of PFGD of the CNS was made were retrieved. Patients in whom an infective agent was shown either by culture, special staining techniques, or by immunohistochemical methods were excluded. We identified 11 patients (eight male, three female) who fulfilled the pathological criteria for this condition. Average age at diagnosis was 38.7 years (range, 17 to 78). Neurological symptoms were the presenting feature in nine patients. Neuroimaging findings included hydrocephalus (54.5%), meningeal enhancement (45.5%), and mass lesions (45.5%). Seven patients had antemortem CNS biopsies (brain/meninges [n = 6], spinal [n = 1]), which showed noncaseating granulomas. Eight patients died (mortality rate: 72.7%). Postmortem examination showed granulomatous involvement of the leptomeninges and cerebral parenchyma in all cases with systemic involvement in 50%, chiefly in the form of noncaseating granulomas of the hilar nodes. Six patients fulfilled the clinical, radiological, and pathological diagnostic criteria for neurosarcoidosis. The remaining five patients had an unclassifiable pathogen-free granulomatous disease of the CNS. PFGD of the CNS are associated with a poor prognosis. Although neurosarcoidosis may account for some of the cases, there remains an unclassifiable subgroup that continues to be a diagnostic and management challenge.

A multi-laboratory evaluation of in vitro platelet assays: the tests for extent of shape change and response to hypotonic shock. Biomedical Excellence for Safer Transfusion Working Party of the International Society of Blood Transfusion

BACKGROUND

There is no consensus regarding the use of specific in vitro tests for the assessment of the quality of platelet components. A literature review found that the platelet discoid shape as measured photometrically by the extent of shape change (ESC) and hypotonic shock response (HSR) correlated well with in vivo viability. The purpose of this study was to determine whether multiple research laboratories can perform the ESC and HSR assays in an accurate, reproducible manner, with acceptable sensitivity and comparable results.

STUDY DESIGN AND METHODS

Eleven laboratories conducted five identical experiments, each with a different unit of platelet-rich plasma (PRP). For each experiment, 2 half-units of PRP were prepared and stored overnight: 1 half-unit at 20 to 24 degrees C in CPD (CPD-PRP) and the other at 1 to 6 degrees C with 2 mg per mL of EDTA (cold EDTA-PRP) added to produce spherical platelets with reduced HSR. Platelet suspensions having different proportions of the two PRPs were prepared and evaluated in duplicate by ESC and HSR assays, and morphologically scored by microscopy. One-way ANOVA and Duncan multiple-range tests were performed to determine significant differences in assay results for suspensions having different proportions of CPD-PRP.

RESULTS

Comparable ESC (mean range: 20-28% for CPD-PRP and 1-6% for cold EDTA-PRP) and HSR (mean range: 58-81% for CPD-PRP and 12-31% for cold EDTA-PRP) measurements were obtained by nine laboratories. Duplicate testing showed high reproducibility of ESR and HSR results /in all laboratories. A 25-percent difference in the proportion of CPD-PRP (indicative of a difference of approximately 25% in the proportions of discoid and spherical platelets) was detected with a sample size of five (p<0.05) for both the ESC and HSR assays. A high correlation was found for the ESC assay and morphology score (r = 0.93, n = 345).

CONCLUSION

Multiple laboratories were able to obtain comparable results with the ESC and HSR tests. They were able to show that the tests can be performed in an accurate, reproducible manner and with acceptable sensitivity.

Expression of nitric oxide synthase-2 in glia associated with CNS pathology

This chapter discusses the expression of nitric oxide synthase-2 (NOS-2) in glia associated with central nervous system (CNS) pathology. The production of nitric oxide (NO) in the nervous system is catalyzed by three, highly homologous isoforms of NO synthase (NOS). NOS-2, the dimeric, heme-containing, soluble protein whose activity is independent of a rise in intracellular calcium, is variously termed ‘inducible,’ ‘immunologic,’ and ‘macrophage NOS (macNOS).’ Nitric oxide inhibits not only NOS-2 activity but also regulates the level of NOS-2 messenger RNA (mRNA) expression through a mechanism involving NF-^K B. There is specific evidence for the glial expression of NOS-2 associated with neuronal injury and infection of the CNS and in neurodegenerative and demyelinating diseases. Direct injury in the CNS results in a reactive gliosis, characterized by the induction of the glial fibrillary acidic protein gene and changes in astrocyte morphology.

Expression of monocyte chemoattractant protein (MCP-1) and nitric oxide synthase-2 following cerebral trauma

Traumatic injury to the brain initiates multiple interrelated processes that involve parenchymal, vascular, and infiltrating inflammatory cells. Nitric oxide (NO) and chemokines have been implicated as regulators of the central nervous system injury response. Following a cryogenic lesion of the cerebral cortex in mice, mRNA for NO synthase (NOS)-2 was detected by reverse transcriptase polymerase chain reaction ipsilaterally 12 h after injury and persisted for 2 weeks. While mRNA was also detected contralaterally, the time course of expression was shorter (1 week). By immunohistochemistry, NOS-2 protein was initially detected ipsilaterally 12 h after injury in infiltrating inflammatory cells. Astroglial cells expressed NOS-2 from 24 to 72 h after injury. The expression of monocyte chemoattractant protein (MCP-1) mRNA peaked at 6 h on the lesion side, remained for 24 h and then declined by 48 h. On the unlesioned side, MCP-1 mRNA was expressed to a much lesser extent and had declined by 24 h. The up-regulation of MCP-1 was relatively specific as a closely related mRNA encoding IP-10 was not significantly increased. These findings implicate a role for NOS-2 and MCP-1 as potential regulators of cellular events following cryogenic cerebral trauma.

The hyper-CVAD regimen improves outcome in relapsed acute lymphoblastic leukemia

Sixty-six adults with refractory acute lymphocytic leukemia received salvage therapy with the 'hyper-CVAD' regimen, consisting of eight courses of alternating intensive chemotherapy with growth factor support, followed by oral maintenance chemotherapy. Their outcome was compared with 63 prognostically similar historical control patients treated with high-dose Ara-C plus mitoxantrone with or without GM-CSF. Overall, the complete response rates were similar in the treatment and control groups (29 of 66 (44%) vs 24 of 63 (38%)). There were more patients in the current study with primary resistant disease (10 of 66 (15%) vs one of 63 (2%), P = 0.006), and conversely fewer patients with secondary resistance (19 of 66 (29%) vs 28 of 63 (44%), P = 0.06). Recovery of granulocyte counts above 500/microl was significantly faster in the current study when compared to high-dose Ara-C-treated patients who were given GM-CSF (20 vs 25 days, P = 0.04). Survival was prolonged in the hyper-CVAD-treated patients, with most of the benefit seen in first salvage patients (42 vs 20 weeks, P = 0.016). When only first salvage patients were considered, there was a significant difference in disease-free survival in favor of hyper-CVAD (52 vs 20 weeks, P = 0.008). The hyper-CVAD regimen is a more effective and less toxic salvage regimen for relapsed acute lymphocytic leukemia than high-dose Ara-C-based regimens.

Diagnosis of neurosyphilis: appraisal of clinical caseload

OBJECTIVES

To review the management of a cohort of patients with positive treponemal serology and psychiatric and/or neurological disorders.

METHODS

A retrospective case note review of 172 patients with positive treponemal serology attending the Patrick Clement's Clinic, Central Middlesex Hospital between December 1990 and November 1995 was performed.

RESULTS

101 men and 71 women were new attenders diagnosed with positive treponemal serology. A neurological problem was identified in 27 patients (12 women and 15 men) with psychiatric and/or neurological disorders, of whom 20 (six women and 14 men) underwent investigation of the cerebrospinal fluid (CSF). With the medical history and results of CSF-RPR and FTA tests, white cell count (WCC), and total protein level in the CSF, 10 patients (eight men and two women) were diagnosed with likely neurosyphilis and 17 with neurological disorders not thought to be caused by syphilis. The clinical features in those having neurosyphilis were sensorineural hearing loss (n = 5) and tabes dorsalis (n = 5). In the seven patients diagnosed with neurosyphilis who underwent CSF examination one patient had a reactive CSF-FTA, elevated protein, and elevated WCC; one patient had a reactive CSF-FTA and RPR with elevated protein; the total protein only was elevated in three cases and the WCC elevated in one case. Nine of the 10 patients with neurosyphilis received adequate neurosyphilitic treatment; one patient was lost to follow up.

CONCLUSIONS

The management of patients with positive treponemal serology and psychiatric and/or neurological disorders was consistent. Patients with suspected neurosyphilis or patients with neurological signs compatible with neurosyphilis (who did not undergo CSF examination) were treated with adequate neurosyphilitic therapy.