Itzchak Beiran, MD, Tamar Talmon, MD and Benjamin Miller, MD
Background: The prevalence of traumatic hyphema as well as the distribution of its severity varies between different patient populations. Treatment recommendations in the literature differ significantly among various published reports. This lack of a uniformly accepted treatment probably reflects the different characteristics of this pathology among the populations investigated and calls for a population-adjusted treatment recommendation.
Objectives: To report the characteristics and functional outcome of patients with traumatic hyphema and to discuss possible recommendations regarding the use of ε‑aminocaproic acid.
Methods: A prospective, non-randomized study was conducted among 154 consecutive patients with traumatic hyphema, including data collection of ophthalmic status at various time points, the presence or absence of secondary hemorrhage, and final visual acuity.
Results: Of the 154 eyes studied over 3½ years, nearly 90% had hyphema of grade 1 or less, 3 (3.25%) experienced rebleeding, and 2 (1.3%) – neither of which rebled – needed surgical intervention. None of the four patients who experienced final visual acuity of 6/40 or less suffered rebleeding.
Conclusion: The use of ε‑aminocaproic acid in the studied population was unjustified and routine use of e-aminocaproic acid in our patient population is probably not indicated. A treatment policy regarding e-aminocaproic acid use should be adjusted to the population being treated.
by Melvin H. Freedman, MD, FAAP, FRCPC and Blanche P. Alter, MD, FAAP, MPH
Background: Granulocyte colony-stimulating factor has had a major impact on the management of severe chronic neutropenia – a collective term referring to congenital, idiopathic, or cyclic neutropenia. Almost all patients respond to G-CSF with increased neutrophils, reduced infections, and improved survival. Some responders with congenital neutropenia (termed Kostmann’s syndrome herein) and Shwachman-Diamond syndrome have developed myelodysplastic syndrome and acute myeloid leukemia, which raises the question of the role of G-CSF in pathogenesis. The issue is complicated because both disorders have a propensity for MDS or AML as part of their natural history.
Objective and Methods: To address this, the Severe Chronic Neutropenia International Registry used its large database of chronic neutropenia patients treated with G-CSF to determine the incidence of malignant myeloid transformation in the two disorders, and its relationship to treatment and to other patient characteristics.
Results: As of January 2001, of the 383 patients with congenital forms of neutropenia in the Registry, 48 had MDS or AML (crude rate, about 12.5%). No statistically significant relationships were found between age at onset of MDS or AML and patient gender, G-CSF dose, or duration of G-CSF therapy. What was observed, however, was the multistep acquisition of aberrant cellular genetic changes in marrow cells from Kostmann’s syndrome patients who transformed, including activating ras oncogene mutations, clonal cytogenetic abnormalities, and G-CSF receptor mutations. The latter in murine models produces a hyperproliferative response to G-CSF, confers resistance to apoptosis, and enhances cell survival.
Conclusions: Since Kostmann’s syndrome and Shwachman-Diamond syndrome are inherited forms of bone marrow failure, G-CSF may accelerate the propensity for MDS/AML in the genetically altered stem and progenitor cells, especially in those with G-CSF receptor and ras mutations (82% and 50% of Kostmann’s syndrome patients who transform, respectively). Alternatively, and equally plausible, G-CSF may simply be an innocent bystander that corrects neutropenia, prolongs patient survival, and allows time for the malignant predisposition to declare itself. Only careful long-term follow-up of the cohort of patients receiving G-CSF will provide the answer.
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G-CSF = granulocyte colony-stimulating factor
MDS = myelodysplastic syndrome
AML = acute myeloid leukemia
Shifra Sela, PhD, Revital Shurtz-Swirski, PhD, Jamal Awad, MD, Galina Shapiro, MSc, Lubna Nasser, MSc, Shaul M. Shasha, MD and Batya Kristal, MD
Background: Cigarette smoking is a well-known risk factor for the development of endothelial dysfunction and the progression of atherosclerosis. Oxidative stress and inflammation have recently been implicated in endothelial dysfunction.
Objectives: To assess the concomitant contribution of polymorphonuclear leukocytes to systemic oxidative stress and inflammation in cigarette smokers.
Methods: The study group comprised 41 chronic cigarette-smoking, otherwise healthy males aged 45.0 ± 11.5 (range 31–67 years) and 41 male non-smokers aged 42.6 ± 11.3 (range 31–65) who served as the control group. The potential generation of oxidative stress was assessed by measuring the rate of superoxide release from separated, phorbol 12-myristate 13-acetate-stimulated PMNL and by plasma levels of reduced (GSH) and oxidized (GSSG) glutathione. Inflammation was estimated indirectly by: a) determining the in vitro survival of PMNL, reflecting cell necrosis; b) in vivo peripheral PMNL counts, reflecting cell recruitment; and c) plasma alkaline phosphatase levels, indicating PMNL activation and degranulation.
Results: PMA-stimulated PMNL from cigarette smokers released superoxide at a faster rate than PMNL from the controls. Smokers had decreased plasma GSH and elevated GSSG levels. In vitro incubation of control and smokers' PMNL in sera of smokers caused necrosis, while control sera improved smoker PMNL survival. Smokers' PMNL counts, although in the normal range, were significantly higher than those of controls. Plasma ALP levels in smokers were significantly higher than in controls and correlated positively with superoxide release and PMNL counts.
Conclusions: Our study shows that PMNL in smokers are primed in vivo, contributing concomitantly to systemic oxidative stress and inflammation that predispose smokers to endothelial dysfunction, and explains in part the accelerated atherosclerosis found in smokers.
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PMNL = polymorphonuclear leukocytes
PMA = phorbol 12-myristate 13-acetate
GSH = reduced glutathione
GSSG = oxidized glutathione
ALP = alkaline phosphatase
Yair Galili, MD and Arie Bass, MD
Peter C. Harpel, MD and Nasreen S. Haque, PhD
Chemokines and their receptors play regulatory roles in inflammatory reactions. Lipoprotein(a) is an atherogenic lipoprotein, however the mechanisms of its actions are not defined. Our interest in chemokines and their receptors was stimulated by the finding that incubation of Lp(a) with human umbilical vein endothelial cells produced a conditioned medium that was chemotactic for human monocytes. Since infiltration of monocytes into the vessel wall is an early lesion in atherosclerosis, this finding provided a novel mechanism to explain the relationship between Lp(a) and atherosclerosis. The chemoattractant produced by HUVEC was identified as CCL1/I-309, a CC chemokine previously reported to be secreted by stimulated monocytes/macrophages and T lymphocytes. CCR8, the CCL1 receptor, was identified on endothelial cells, and CCL1 was found to be a chemoattractant for these cells. Most recently we demonstrated functional CCR8 on human vascular smooth muscle cells and found that the Lp(a)-HUVEC conditioned medium is a chemoattractant for these cells. CCL1 increased metalloproteinase-2 production by HUVEC, an activity that enables these cells to remodel the vascular matrix. These studies suggest that CCR8 may play an important role in arterial wall pathology.
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Lp(a) = lipoprotein(a)
HUVEC = human umbilical vein endothelial cells
Seth J. Corey, MD and Quan-Sheng Zhu, MD
Philip Vaughan, MBBS, Jeremy Gardner, MBBS, Francesca Peters, MBBS, MRCP and Rosalind Wilmott, RGN
Htwe. M. Zaw, MBBS, MRCS, Ian. C. Osborne, MBBS, Philip. N. Pettit, MBBS, MRCS, and Alexander. T. Cohen, MBBS, MSc, MD, FRACP
Tomas Ganz, PhD, MD
Systemic infection or inflammation causes a decrease in intestinal iron absorption and impairs the release of recycled iron from macrophages. Decreased availability of iron may deny this essential element to invading pathogens and may inhibit their multiplication and other metabolic processes but also results in anemia of chronic disease. This article reviews recent discoveries that shed light on the regulation of iron metabolism during infection and iron overload, and point to the central role of a newly discovered peptide, hepcidin. Evidence to date indicates that hepcidin is a negative regulator of intestinal iron absorption, placental iron transport, and the release of iron from macrophages that recycle iron from senescent red cells. It may also be the central mediator of iron sequestration during infections and inflammatory states and the mediator of anemia of chronic disease. Rapid progress in this area is a good example of the beneficial effects of improvements in peptide analysis and chemistry, advances in genomics, and the increasing use of transgenic mice to determine the function of newly discovered genes and proteins.
Liat Nadav, MD, Benjamin Geiger, PhD and Ben-Zion Katz, PhD
Avinoam Shuper, MD, Batia Stark, MD, Liora Kornreich, MD, Ian J. Cohen, MBChB, Gali Avrahami, MD and Isaac Yaniv, MD
The addition of methotrexate to treatment protocols in children with acute lymphoblastic leukemia has been found beneficial in preventing central nervous system relapse. However, MTX itself may be associated with neurologic morbidities, the most significant of which is leukoencephalopathy. The present study describes the clinical spectrum of leukoencephalopathy, which ranges from a subclinical disease manifested only radiologically to a progressive, devastating encephalopathy. The interaction of MTX with other components of the treatment protocol is discussed, as is the effect of leucovorin. A summary is presented of the metabolic pathways that may be involved in the development of MTX toxicity. Researchers are still seeking a biochemical marker to aid in the determination of the amount of MTX that may be safely administered.
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Arnon Blum, MD, Julia Sheiman, MD and Yonathan Hasin, MD
Joseph D. Rosenblatt, MD, Seung-Uon Shin, PhD, Hovav Nechustan, MD, PhD, Kyung Hee Yi, BSc and Khaled Tolba, MD