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Biomedical subjects

R M Silver

Publications and source records attributed to R M Silver.

At least 91 records · Page 5Linked to original sources

Tryptophan metabolism via the kynurenine pathway in patients with the eosinophilia-myalgia syndrome.

OBJECTIVE: To investigate the metabolism of L-tryptophan (LT) via the kynurenine pathway in patients with the eosinophilia-myalgia syndrome (EMS). METHODS: Measurement of LT, L-kynurenine, and quinolinic acid in plasma and cerebrospinal fluid (CSF) from subjects with EMS, from asymptomatic users of LT, and from normal subjects. RESULTS: Plasma LT concentrations were lower in untreated EMS patients (n = 5) than in corticosteroid-treated EMS patients (n = 5; P less than 0.05) and in asymptomatic users of LT (n = 5; P less than 0.05). Untreated EMS patients, who had discontinued LT weeks to months prior to study, had significantly higher plasma levels of L-kynurenine and quinolinic acid than did corticosteroid-treated EMS patients (P less than 0.05), normal subjects (P less than 0.02), and asymptomatic users of LT (P less than 0.05). EMS patients also had significantly elevated levels of L-kynurenine (P less than 0.05) and quinolinic acid (P less than 0.001) in CSF compared with normal subjects. After a 1-gm oral dose of LT, untreated EMS patients (n = 4) showed lower peak levels of LT and accentuated synthesis of L-kynurenine and quinolinic acid, compared with these values in corticosteroid-treated EMS patients (n = 2), who responded like normal subjects (n = 5). CONCLUSION: These data demonstrate that during the active phase of EMS, LT metabolism via the kynurenine pathway was accentuated, probably secondary to induction of the enzyme indoleamine-2,3-dioxygenase. Ingestion of large amounts of LT (median daily dose 1.5 gm) resulted in high concentrations of kynurenine-pathway metabolites in blood and extrahepatic tissues, which was accentuated in EMS patients and which may have played a significant role in the pathogenesis of the disease.

Adrenal Cortex Hormones↗

A histopathologic comparison of Shulman's syndrome (diffuse fasciitis with eosinophilia) and the fasciitis associated with the eosinophilia-myalgia syndrome.

A comparison of the histopathologic features of Shulman's syndrome (diffuse fasciitis with eosinophilia) and the fasciitis associated with the eosinophilia-myalgia syndrome is presented. The study population consisted of eight biopsy specimens of seven patients with Shulman's syndrome and 11 specimens from 10 patients with eosinophilia-myalgia syndrome. Both groups exhibited inflammatory changes in the subcutaneous fat, septa, and fascia; cutaneous changes were more prominent in cases of eosinophilia-myalgia syndrome. Eosinophils and plasma cells were not consistently present in either condition; mast cells and factor XIIIa-positive cells were consistently present in the inflammatory infiltrates. Although there was overlap in the histopathologic findings, Shulman's syndrome tends to involve the subcutis alone and the eosinophilia-myalgia syndrome tends to be a pancutaneous-subcutaneous process.

Eosinophilia↗

Outcome of treated pregnancies in women with antiphospholipid syndrome: an update of the Utah experience.

OBJECTIVE: To determine the outcome of treated pregnancies in women with well-characterized antiphospholipid syndrome. METHODS: We reviewed 82 consecutive pregnancies in 54 women with antiphospholipid syndrome who were treated during pregnancy with the following: 1) prednisone and low-dose aspirin; 2) heparin and low-dose aspirin; 3) prednisone, heparin, and low-dose aspirin; or 4) other combinations of these medications or immunoglobulin. RESULTS: The overall neonatal survival rate was 73%, excluding spontaneous abortions, but treatment failures (fetal and neonatal deaths) occurred in all treatment groups. Patients with successful treated pregnancies had fewer previous fetal deaths than those with unsuccessful treated pregnancies. There were no significant differences in outcome among the four treatment groups. Preeclampsia and fetal distress occurred in half of all pregnancies, and fetal growth impairment occurred in nearly one-third. Preterm delivery due to maternal or fetal indications was required in 37% of the pregnancies. Four pregnancies were also complicated by postpartum thrombosis during treatment. CONCLUSIONS: Pregnancy in women with antiphospholipid syndrome appears to be improved by treatment, but fetal loss may occur despite treatment. Preeclampsia, fetal distress, fetal growth impairment, and premature delivery are common. Because of the clinically significant risk of thrombotic episodes, thrombosis prophylaxis should be considered in these patients.

Antiphospholipid Syndrome↗

Eosinophilia-myalgia syndrome, toxic-oil syndrome, and diffuse fasciitis with eosinophilia.

The eosinophilia-myalgia syndrome, which is associated with the ingestion of L-tryptophan that contained products, occurred as an epidemic in the United States in 1989. Eosinophilia-myalgia syndrome is similar in many ways to the toxic-oil syndrome, which occurred in Spain in 1981, and to diffuse fasciitis with eosinophilia, which has been noted since 1974 to occur sporadically. Recent studies have clarified the epidemiology, histopathology, and clinical features of eosinophilia-myalgia syndrome. These studies are reviewed, and comparisons to the related syndromes, toxic-oil syndrome and diffuse fasciitis with eosinophilia, are made.

Brassica↗

Growth and characterization of fibroblasts obtained from bronchoalveolar lavage of patients with scleroderma.

We describe the detection and the growth of fibroblasts with human smooth muscle cell differentiation features from bronchoalveolar lavage (BAL) fluid of 53% of patients with scleroderma, but not from healthy controls. The binding of alpha-actin, vimentin and desmin antibodies by scleroderma lung fibroblasts exceeded that of normal adult lung fibroblasts, indicating that scleroderma lung fibroblasts express some markers of human smooth muscle cell differentiation (myofibroblasts), which may account for differences in biological behavior. A mesenchymal cell phenotype was documented by mRNA analysis, showing high expression of collagen type I and fibronectin in these cells. Fibronectin is also released in significantly higher amounts by scleroderma alveolar macrophages than by macrophages from healthy donors.

Actins↗

Alterations in tryptophan metabolism in the toxic oil syndrome and in the eosinophilia-myalgia syndrome.

The eosinophilia-myalgia syndrome (EMS) was associated with ingestion of L-tryptophan containing products and was accompanied by altered metabolism of L-tryptophan during the active phase. Many patients with EMS exhibited clinical and histopathological features similar to another epidemic, the toxic oil syndrome (TOS), associated with ingestion of adulterated rapeseed oil. We hypothesized that patients with TOS, like patients with EMS, may have had altered metabolism of L-tryptophan during the acute phase of the illness. Therefore, we quantitated the tryptophan metabolites, L-kynurenine and quinolinic acid, and we measured neopterin, a marker of interferon-gamma (IFN-gamma), in blood obtained during the acute phase of each syndrome. Patients with TOS or EMS had significantly higher L-kynurenine and quinolinic acid than healthy control subjects or rheumatic disease control subjects. Neopterin was also elevated in patients with untreated TOS and EMS, and correlated strongly with L-kynurenine and quinolinic acid. Our data suggest that indoleamine-2,3-dioxygenase (IDO), the rate limiting enzyme of the kynurenine pathway of L-tryptophan metabolism, was activated in both syndromes by cytokines including IFN-gamma, and that perhaps products of tryptophan metabolism played a role in the pathogenesis of EMS and TOS.

Arthritis, Rheumatoid↗

Life-threatening puerperal infection due to group A streptococci.

We describe two patients with life-threatening puerperal infection due to group A beta-hemolytic streptococcus. Each patient had bacteremia, shock, and multi-organ involvement. Both cases were compatible with a recently described streptococcal toxic shock-like illness. Both women failed to improve despite vigorous medical and antibiotic therapies, and each required hysterectomy. Obstetricians should be alert to the importance of early diagnosis and treatment of this potentially lethal infection.

Adult↗

Postmortem studies of the heart in three fatal cases of the eosinophilia-myalgia syndrome.

OBJECTIVE: To examine the hearts of individuals who died from the eosinophilia-myalgia syndrome associated with ingestion of L-tryptophan, with particular attention paid to the coronary arteries, the neural structures, and the conduction system of the heart because of reported terminal disturbances of cardiac rhythm and conduction. STUDY MATERIAL: Three hearts fixed in neutral formalin and well preserved with all the relevant areas of conduction system intact. METHODS: Light microscopic examination of subserial sections of the sinus node, atrioventricular node and His bundle, coronary chemoreceptor and regional nerves, ganglia, and small coronary arteries. Routine stains used were Goldner trichrome and Verhoeff-van Gieson. RESULTS: Arterial abnormalities were numerous and primarily of two types: focal fibromuscular dysplasia causing moderate to severe narrowing, as well as endarteritis and panarteritis. Extensive examples of neuritis and ganglionitis were present throughout the heart, including the conduction system, where arterial abnormalities were also abundant. In the coronary chemoreceptor there were both old and new lesions comprising focal inflammation with degeneration as well as older areas of fibrotic destruction. Within the sinus node, areas of dense fibrosis replaced all nodal tissue. These abnormalities were similar in nature and extent in all three hearts. CONCLUSIONS: The pathologic lesions present in the coronary arteries, neural structures, and conduction system of the heart in patients who died from the eosinophilia-myalgia syndrome provide a suitable anatomic substrate for substantial cardiac electrical instability, including the occurrence of sudden death. In cases of unexplained cardiac electrical instability or sudden unexpected death an inquiry should be made about previous use of L-tryptophan. In patients with the eosinophilia-myalgia syndrome, the possibility of cardiac electrical instability should be considered as part of long-range clinical management.

Aged↗

Clinical aspects of localized and systemic scleroderma.

A number of reports of potential etiologic agents of localized and systemic scleroderma appeared in the past year, including alterations in tryptophan metabolism, use of appetite suppressants, and exposure to silicone. An infectious agent, Borrelia burgdorferi, was found not to be implicated in localized scleroderma. The improvement in outcome of systemic scleroderma complicated by renovascular hypertension was highlighted in several papers, as was the emerging importance of cardiac and pulmonary involvement. Recent advances in the early detection and evaluation of cardiac and pulmonary complications of scleroderma are discussed.

Humans↗

High resolution computed tomography in early scleroderma lung disease.

Seventeen patients with early systemic sclerosis (SSc) underwent high resolution computed tomography (HRCT) of the chest to evaluate dyspnea and/or abnormal pulmonary function tests (PFT). All patients were assigned a dyspnea score and each had routine chest radiography (CXR). Bronchoalveolar lavage (BAL) was performed on 10 patients. HRCT was abnormal in 15 patients (88%), while CXR was abnormal in only 10 patients (59%). Mediastinal lymphadenopathy was detected in 7 patients (41%). Disease duration, dyspnea score, and forced vital capacity (FVC) did not correlate with HRCT score. However, trends toward higher total BAL cell counts and higher BAL neutrophil counts were noted in patients with ground glass opacities on HRCT, and BAL lymphocyte counts were significantly higher in such cases. HRCT is superior to CXR for detecting early interstitial lung disease in SSc, but patient history and FVC correlate poorly with HRCT findings. Ground glass opacities on HRCT may reflect active alveolitis, and mediastinal lymphadenopathy associated with SSc lung disease may be a consequence of pulmonary inflammation.

Adult↗

Scleroderma, fasciitis, and eosinophilia associated with the ingestion of tryptophan.

An association between the ingestion tryptophan and a syndrome characterized by scleroderma-like skin abnormalities, fasciitis, and eosinophilia has recently been recognized in the United States. We report the clinical and histopathological findings in nine patients and the results of biochemical analyses of tryptophan metabolism in seven patients with this syndrome. Edema of the extremities, frequently accompanied by pruritus, paresthesia, and myalgia, developed in the nine patients (six women and three men; age range, 30 to 66 years) 1 to 18 months after the start of therapy with tryptophan (1.5 to 3.0 g daily) for insomnia, depression, or obesity. Five patients were taking drugs (benzodiazepines) known to inhibit hypothalamic-pituitary-adrenal function, and one had adrenal insufficiency. All had blood eosinophilia in the acute phase of their illness (mean eosinophil count [+/- SD], 3.62 +/- 2.87 X 10(9) cells per liter). All had histopathological changes in the dermis and subcutaneous tissue typical of scleroderma, and seven patients had eosinophils. The fascia was inflamed and fibrotic, and adjacent skeletal muscle often showed perifascicular inflammation. Tryptophan was discontinued in all patients, and eight received prednisone. The cutaneous symptoms improved, but only two patients had complete resolution of their illness. The patients had plasma levels of tryptophan before and after an oral dose of tryptophan that were similar to those in normal subjects. Plasma levels of L-kynurenine and quinolinic acid, which are metabolites of tryptophan, were significantly higher in four patients with active disease than in three patients studied after eosinophilia had resolved or in five normal subjects (P less than 0.001)--findings consistent with the activation of the enzyme indoleamine-2,3-dioxygenase. This illness resembles eosinophilic fasciitis and probably represents one aspect of the recently reported eosinophilia-myalgia syndrome. The development of the syndrome may result from a confluence of several factors, including the ingestion of tryptophan, exposure to agents that activate indoleamine-2,3-dioxygenase, and possibly, impaired function of the hypothalamic-pituitary-adrenal axis.

Adult↗

Scleroderma following augmentation mammoplasty. Report of a case and review of the literature.

A 46-year-old woman developed localized scleroderma after surgical manipulation of her silicone gel-filled breast prostheses. She developed firm, shiny plaques on her legs that progressed to involve the thighs. Histopathologic examination of a deep-skin biopsy specimen confirmed the diagnosis of scleroderma. On surgical removal of the silicone implants, and their replacement with saline-filled implants, the scleroderma gradually resolved. Histopathologic examination of the removed implant capsules revealed evidence of silicone leakage. All new female patients with scleroderma should be questioned and examined regarding augmentation mammoplasty. Until prospective studies are completed on the possible association between scleroderma and silicone breast implants, it would seem prudent to use the saline-filled, elastomeric envelope-type breast implant for augmentation mammoplasty rather than the silicone gel-filled implant.

Breast↗

Evaluation and management of scleroderma lung disease using bronchoalveolar lavage.

PURPOSE: Bronchoalveolar lavage (BAL) was performed in 43 nonsmoking patients with scleroderma (systemic sclerosis) to determine the frequency of alveolitis, the status of BAL findings over time, and the relationship of such findings to pulmonary status initially and at follow-up. PATIENTS AND METHODS: Forty-three nonsmoking patients with systemic sclerosis underwent extensive pulmonary evaluation including pulmonary function tests, chest radiographs, and BAL with analysis of cells, IgG, albumin, immune complexes, and fibronectin. RESULTS: Alveolitis was detected on initial BAL evaluation in 21 patients (49%). Alveolitis was characterized by hypercellular lavage fluid, due to an absolute increase in alveolar macrophages and due to an increase in both the absolute number and percentage of granulocytes (neutrophils and eosinophils). Patients with systemic sclerosis had significantly higher levels of IgG and immune complexes in BAL fluid than did control subjects, and alveolar macrophages from patients with systemic sclerosis released higher amounts of fibronectin in vitro. In serial studies, alveolitis was found to persist. Patients with alveolitis had greater dyspnea than patients without alveolitis (p = 0.02), and they had greater reductions in lung volumes and carbon monoxide diffusing capacity (DLCO) (p = 0.004). Furthermore, patients with persistent alveolitis had significantly greater reductions in pulmonary function over time than patients without alveolitis (forced vital capacity [FVC]: -0.69 L versus -0.05 L, p less than 0.001; DLCO: -2.94 mL/minute/mm Hg versus +0.16 mL/minute/mm Hg, p = 0.03). BAL was used to select patients with alveolitis and at risk of pulmonary deterioration, and treatment was instituted with cyclophosphamide and prednisone, resulting in significant improvement in dyspnea (p less than 0.001) and the rate of change of FVC (p = 0.02) and DLCO (p less than 0.001). CONCLUSION: We conclude that alveolitis occurs frequently in systemic sclerosis and that BAL is useful in identifying such patients who are at risk for a further decline in pulmonary status. Preliminary observations suggest that treatment of patients with active alveolitis may result in improvement in pulmonary status.

Adult↗