Eosinophilia in Rheumatologic/Vascular Disorders.

Peripheral and tissue eosinophilia can be a prominent feature of several unique rheumatologic and vascular diseases. These diseases span a wide range of clinical features, histologic findings, therapeutic approaches, and outcomes. Despite the rare nature of these entities--which makes large-scale studies challenging--knowledge has continued to grow regarding their epidemiology, pathophysiology, and management. This review compares and contrasts 5 rheumatologic and vascular conditions in which eosinophilia can be seen: eosinophilic granulomatosis with polyangiitis (Churg-Strauss), immunoglobulin G4-related disease, diffuse fasciitis with eosinophilia, eosinophilia-myalgia syndrome, and eosinophilic myositis.

[Diagnostic problems in eosinophilic fasciitis]. / Problemy diagnostyczne zwiazane z eozynofilowym zapaleniem powiezi.

We presented two cases with symptoms of diffuse swelling of subcutaneous tissue, stiffness and tenderness of involved areas, fever, eosinophilia and hypergammaglobulinemia. The inflammatory infiltrates consisting of lymphocytes, plasma cells and eosinophils were yielded in fascia. The difficulties in differentition of the symptoms between eosinophilic fasciitis and "eosinophilia-myalgia syndrome" are discussed.

Eosinophilic perimyositis as the presenting feature of a monoclonal T-cell expansion.

A 51-year-old physically active man was investigated for exertional myalgias and muscle stiffness. On examination he had mild proximal muscle weakness of the upper extremities and retraction of the digit flexors. Blood eosinophilia was present, but serum creatine kinase (CK) levels and an electromyographic study were normal. A skin-fascia-muscle biopsy of the calf revealed a macrophagic and CD4+ T-cell infiltration of the perimysium, and a T-cell expansion was observed in blood, bone marrow, and muscle. A diagnosis of eosinophilic perimyositis was made, and prednisone and azathioprine were administrated with a good clinical response. This case highlights the differential diagnosis of blood eosinophilia with muscle disorders, and underscores that eosinophilic perimyositis may be the expression of a T-cell monoclonal expansion. Although the pathogenesis behind the T-cell expansion is unclear but probably inflammatory, we suggest regular follow-up to allow early treatment of any T-cell lymphoproliferative malignancy that may develop.

Eosinophilia-myalgia syndrome: selective cognitive impairment, longitudinal effects, and neuroimaging findings.

OBJECTIVE: To identify the specific nature of the neurocognitive impairments of eosinophilia-myalgia syndrome (EMS) in an unselected population, and to present longitudinal patterns. METHODS: A consecutive sample of 23 patients with EMS and 18 age and education matched control subjects were assessed on a comprehensive neuropsychological battery. Longitudinal results were gathered from six patients. RESULTS: Neurocognitive impairments were found which represent a subset of deficits reported in previous group and case study reports. Deficits were limited to complex visual memory, conceptual set shifting, and attention, which suggest a selective dysexecutive syndrome. The motor slowing and verbal memory deficits previously reported were not found. Although depression, fatigue, sleep deprivation, and pain were significant symptoms, they were unassociated with deficits with the exception of an association of depression with one deficit. There was no pattern of overall decline over time in a subset of the group, although considerable heterogeneity in the longitudinal patterns of neurocognitive tests was found. Abnormalities of white matter appeared in the MRI of eight of 12 patients. CONCLUSIONS: The neurocognitive and neuroimaging findings contribute to the evidence which indicates that the neural substrate of EMS is white matter damage.

Pathophysiology of the eosinophilia-myalgia syndrome.

Significant morbidity and mortality occur during the acute phase of the eosinophilia-myalgia syndrome (EMS), and many patients still have chronic manifestations of the disease. Although the precise etiologic agent or agents within implicated batches of L-tryptophan remain uncertain, histopathologic studies support a role for a cell mediated immune response underlying the pathophysiology of EMS. The cellular immune response seems to lead to a microangiopathy and release of cytokines that can induce eosinophilia and fibrosis. Such responses are most marked within the dermis, subcutis, fascia, and connective tissue in and around muscles, nerves, and other tissues. The pathophysiology of the chronic symptoms is poorly understood but may involve ischemia, neuropathy, and metabolic abnormalities.

A contaminant of L-tryptophan enhances expression of dermal collagen in a murine model of eosinophilia myalgia syndrome.

The eosinophilia-myalgia syndrome was associated with the ingestion of L-tryptophan products containing a number of contaminants, one of which has been identified as 1,1'-ethylidene-bis-(L-tryptophan) (EBT), also known as peak E or peak 97. In earlier studies, we demonstrated that EBT induces inflammation and fibrosis in dermal and subcutaneous tissue of C57BL/6 mice. Others have shown EBT to be a potent stimulus for fibroblast activation and collagen synthesis in vitro, and dermal tissue from EMS patients reveals evidence of enhanced collagen gene expression. In the present study using Northern blot analysis and in situ hybridization, we demonstrate enhanced expression of genes for types I, III, and VI collagen in the dermis and subcutis of C57BL/6 mice treated with EBT for 3-21 days. Increased type I procollagen mRNA was noted on day 6 of EBT treatment and was followed by enhanced expression of type III and VI procollagen mRNA at day 21. L-Tryptophan, free of contaminants associated with the eosinophilia-myalgia syndrome epidemic, increased dermal collagen mRNA to a lesser extent than did EBT. Increased procollagen gene expression was accompanied by evidence of enhanced TGF-beta 1 expression in the dermis and subcutis. This animal model provides additional evidence for EBT as a causal agent of the eosinophilia-myalgia syndrome and should prove useful in the study of the pathogenesis of that syndrome.

The natural history of eosinophilia-myalgia syndrome in a tryptophan-exposed cohort in South Carolina.

BACKGROUND: In a previous study, we did follow-up on 418 patients who were exposed to tryptophan in 1989, of whom 47 (11%) had definite and 63 (9%) possible eosinophilia-myalgia syndrome (EMS). METHODS: We assessed mortality and clinical spectrum of illness since 1989 for 242 (58%) of the 418 tryptophan-exposed patients from the original study. To assess outcomes, we used hospital and death records, interviewer-administered questionnaires, physical examinations, and laboratory tests. RESULTS: During the follow-up interval, mortality from all causes was 19% in those with definite EMS, 7% in possible EMS, and 3% in those who were not ill. The age- and sex-adjusted mortality in those with definite EMS was more than 3 times that of the general population or of tryptophan users in the practice who were not ill. Six deaths (66%) among the definite EMS case patients occurred during the 18 months immediately after symptom onset. Compared with the tryptophan users who were not ill, survivors with definite EMS continued to report excess morbidity for 6 major EMS symptoms (myalgia, arthralgia, weakness, rash, alopecia, and sclerodermiform skin changes), but they also reported that the symptom number and severity diminished with time. None of the tryptophan users who were not ill in 1989 developed a symptom complex suggesting new EMS during the follow-up interval. CONCLUSIONS: This study assessing a tryptophan-exposed population found those persons who developed EMS during the 1989 epidemic were at increased risk for death, particularly early after disease onset. Survivors reported improvement or resolution of major symptoms, suggesting that the severity of EMS diminishes with time. We found no evidence of delayed onset of EMS in tryptophan users who were not ill in 1989, regardless of the brand used.

Persistent microvasculopathy in chronic eosinophilia-myalgia syndrome.

Acute eosinophilia-myalgia syndrome (EMS) due to contaminated L-tryptophan (LT) exposure is an inflammatory microangiopathy of the dermis, fascia, and muscle. Select individuals evolve from acute EMS to have persistence of myalgia, fatigue, cramps, and skin changes for years. Many develop memory dysfunction and confusion. The objective of this study is to delineate the pathology in individuals with chronic EMS. Seventeen patients with ongoing symptoms representing chronic EMS are studied by skin, fascia, and muscle biopsies four to five years after exposure to contaminated LT and initial onset of EMS. All have microvascular disease. Most have lymphocytic inflammatory infiltrates. Several have dermal sclerosis. The findings indicate that persistent microvascular disease is present in chronic EMS. The pathologic changes are similar to those of acute EMS but with notable differences. Tissue eosinophil infiltration is rare in the chronic state as compared to acute EMS. The persistence of endothelial pathology indicates continuing microvascular dysfunction.

Eosinophilic fasciitis: report of a case diagnosed 14 years after its onset.

The authors describe a case of eosinophilic fasciitis diagnosed 14 years after the onset of the clinical and laboratory manifestations of the disease. Failure to carry out an adeguate histopathological examination during this period played a role in delaying diagnosis.

An eosinophilia-myalgia syndrome related disorder associated with exposure to L-5-hydroxytryptophan.

OBJECTIVE: To determine whether L-5-hydroxytryptophan (L-5-HTP) associated with eosinophiliamyalgia syndrome (EMS) like illness contains impurities in a fashion similar to that described in L-tryptophan associated with EMS. METHODS: Members of a family who became ill after exposure to L-5-HTP were evaluated at the National Institutes of Health. Data from patients with extended exposure to L-5-HTP were also examined. Samples of L-5-HTP were examined using high performance liquid chromatography. RESULTS: One member of the family had EMS, and 2 others had eosinophilia. No patient in the other group reviewed developed the syndrome, although 2 patients developed eosinophilia. The L-5-HTP used by the family contained an impurity not present in samples from the other patient group. After replacement with L-5-HTP not containing this impurity, eosinophilia in 2 family members resolved. CONCLUSION: Some L-5-HTP contains impurities that may be related to L-5-HTP associated EMS.

1,1'-Ethylidenebis[tryptophan] induces pathologic alterations in muscle similar to those observed in the eosinophilia-myalgia syndrome.

1,1'-Ethylidenebis[tryptophan] (EBT), a derivative of L-tryptophan (LT), is a trace contaminant in batches of LT implicated by epidemiologic evidence in the pathogenesis of the eosinophilia-myalgia syndrome (EMS). We treated female Lewis rats with EBT or unimplicated LT (4 mg per 100 grams daily) by intraperitoneal injection. No rash or weakness occurred in either group. All three EBT rats had a few necrotic muscle fibers. In two rats, perimysium and fascia were abnormally thickened and infiltrated with lymphocytes, macrophages, and sparse eosinophils; two rats had sparse perineurial inflammatory cells. Rats treated with unimplicated LT showed no abnormality. These findings replicate an important feature of human EMS and support the epidemiologic evidence linking EBT to the pathogenesis of the human disease.

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

Eosinophilia-myalgia syndrome, a recently described illness, reached epidemic proportions in 1989 and was linked to the ingestion of L-tryptophan containing trace amounts of several contaminants. Eosinophilia-myalgia syndrome shares many clinical and pathologic similarities with toxic-oil syndrome, an epidemic linked to the ingestion of adulterated cooking oil that occurred in Spain in 1981, and to diffuse fasciitis with eosinophilia, a condition first described in 1974. Over the past year, much work has been done in understanding the etiology and pathogenesis of eosinophilia-myalgia syndrome and toxic-oil syndrome. Follow-up data detailing the long-term sequelae and mortality rates for these two conditions are becoming available. The results from these studies are reviewed in this paper.

Eosinophilia-myalgia syndrome: a recent syndrome serving as an alert to new diseases ahead.

A recently recognized disease, the eosinophilia-myalgia syndrome, is described and presented as a new condition attributable to nutritional toxicology. Its etiology is related to the ingestion of L-tryptophan, manufactured by a single Japanese supplier who had modified its production system, which, though of high purity, contained in minute concentrations a number of contaminants or impurities. Patients with eosinophilia-myalgia syndrome develop an eosinophilia with pathologic changes mainly involving skin, muscle, and connective tissue. The findings suggest an autoimmune response. Experimental studies with the implicated L-tryptophan as well as with some contaminants have as yet failed to develop a suitable animal model of eosinophilia-myalgia syndrome. Further studies are needed to unravel the pathogenesis of this complex syndrome. At present, physicians need to be cognizant of this recent syndrome and be aware that other new diseases, induced by nutritional toxicological alterations and possibly related to technicological developments, lie ahead.

Immunohistochemical analysis of lymphocytes in postmortem study of the heart from fatal cases of the eosinophilia myalgia syndrome and of the toxic oil syndrome.

Inflammatory lesions of coronary arteries and cardiac neural structures are postmortem histopathologic features of both the eosinophilia-myalgia syndrome (EMS) and the toxic oil syndrome (TOS). The inflammation is primarily lymphocytic. For further definition of the lymphocytes, immunohistochemical analysis was carried out in the hearts of three victims of EMS and four victims of TOS. Many CD45RO+ T cells, OPD4+ helper/inducer T (Th) cells, and CD20+ B cells were observed in these neurovascular lesions, notably in the conduction system and the coronary chemoreceptor. T cells were prominent in EMS around nerves, ganglia, and sometimes around arteries. B cells and Th cells, however, were more prominent in TOS around arteries. The percentage of T cells in EMS (59.6 +/- 2.4%) was significantly higher than in TOS (45.0 +/- 4.2%), whereas that of B cells was significantly higher in TOS (27.7 +/- 4.4%) than in EMS (17.5 +/- 1.3%) (p < 0.01, respectively). There was no significant difference between the syndromes in the percentages of Th cells. Therefore cytotoxic/suppressor T cells are more prominent in EMS than in TOS. These findings suggest that (1) cellular immune mechanisms are involved in cardioneuropathy in victims of both EMS and TOS; (2) cell-mediated cytotoxicity directed against chemoreceptor neural structures and sinus nodal myocytes is prominent in EMS; and (3) some humoral factors may also be involved in the pathogenesis of TOS.

A murine model of the eosinophilia-myalgia syndrome induced by 1,1'-ethylidenebis (L-tryptophan).

The eosinophilia-myalgia syndrome (EMS) is a recently described disease that has been associated with the ingestion of L-tryptophan containing trace amounts of several impurities. The first such contaminant to be identified and linked epidemiologically to the EMS epidemic was 1,1'-ethylidenebis(L-tryptophan) (EBT), but its role in the etiology and pathogenesis of the syndrome has been controversial. We report the development of inflammation and fibrosis affecting the dermis and subcutis, including the fascia and perimyseal tissues, after the daily intraperitoneal administration of EBT to female C57BL/6 mice. Such changes are accompanied by increased numbers of mast cells, many of which appear to be degranulating. Plasma levels of quinolinic acid, a metabolic product of L-tryptophan via the kynurenine pathway, are reduced initially, and then become elevated when inflammation and fibrosis are more pronounced. The nature and location of the inflammatory cell infiltrate and fibrosis, as well as the presence of mast cells and alterations of L-tryptophan metabolism, are consistent with findings reported in patients with EMS. This murine model suggests that EBT may have been one of the mediators of EMS and should facilitate studies of the pathogenesis of EMS.

Axonal neuropathy in eosinophilia-myalgia syndrome.

Three patients with eosinophilia-myalgia syndrome linked to consumption of L-tryptophan supplement developed a severe sensorimotor axonal neuropathy. All three had myalgia, elevated eosinophil count, and later developed fasciitis. Neuropathy was found at all stages of the illness and resulted in disability which was irreversible despite cessation of L-tryptophan. Nerve conduction studies showed reduced motor and sensory evoked response amplitudes with select sparing of some nerves and the arms were more involved than the legs. Cerebrospinal fluid protein content was increased in one of two patients so tested. Creatine kinase was normal and muscle biopsy showed perimysial inflammation. Sural nerve biopsy in one case showed epineural perivascular inflammation. Our data showed that a severe sensorimotor axonal neuropathy occurs in eosinophilia-myalgia syndrome, suggestive of mononeuritis multiplex.