Toxicology and safety study of L-tryptophan and its impurities for use in broiler feed.

L-tryptophan has been utilized as a feed additive in animal nutrition to improve growth performance, as well as a dietary supplement to alleviate various emotional symptoms in humans. Despite its benefits, concerns regarding its safety arose following the outbreak of eosinophilia-myalgia syndrome (EMS) among individuals who consumed L-tryptophan. The causative material of EMS was determined to be not L-tryptophan itself, but rather L-tryptophan impurities resulting from a specific manufacturing process. To investigate the effect of L-tryptophan and its impurities on humans who consume meat products derived from animals that were fed L-tryptophan and its impurities, an animal study involving broiler chickens was conducted. The animals in test groups were fed diet containing 0.065%-0.073% of L-tryptophan for 27 days. This study aimed to observe the occurrence of toxicological or EMS-related symptoms and analyze the residues of L-tryptophan impurities in meat products. The results indicated that there was no evidence of adverse effects associated with the test substance in the investigated parameters. Furthermore, most of the consumed EMS-causing L-tryptophan impurities did not remain in the meat of broiler chickens. Thus, this study demonstrated the safety of L-tryptophan and some of its impurities as a feed additive.

Safety concerns regarding impurities in L-Tryptophan associated with eosinophilia myalgia syndrome.

L-tryptophan is one of the essential amino acids in humans and across the animal kingdom. It has been widely used as a feed additive for domestic animals and is also administered through dietary supplements in humans. Safety concerns have been raised however since a disease known as eosinophilia-myalgia syndrome (EMS) was reported to be related to L-tryptophan supplements. EMS is a rare condition characterized by inflammation in various organ systems including the muscles, skin, and lungs. Through several studies, it has been speculated that the six components generated during the process of L-tryptophan synthesis are related to the induction of EMS. In this review, we discuss the history of EMS and its controversial correlation with L-tryptophan use reported in several studies. Many in vitro and in vivo studies have been conducted to assess the putative correlation between impurities in L-tryptophan preparations and EMS, but no clear and convincing conclusions have been drawn so far.

Simultaneous determination of L-tryptophan impurities in meat products.

L-tryptophan has been used as a feed additive for swine and poultry and as a nutrient supplement for humans. However, some impurities in L-tryptophan have been reported as causative components of eosinophilia-myalgia syndrome. Therefore, from a safety perspective, it is important to analyze meat samples for these impurities. This study aims to develop an analytical method for the simultaneous detection of L-tryptophan impurities in meat products using LC-MS/MS. Among the various impurities, detection methods for (S)-2-amino-3-(5-hydroxy-1H-indol-3-yl)propanoic acid (5-hydroxytryptophan) (HTP), 1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid (MTCA), 3a-hydroxy-1,2,3,3a,8,8a-hexahydropyrrolo-[2,3-b]-indole-2-carboxylic acid (PIC), and 1,1'-ethylidenebistryptophan (EBT) and 2-(3-indoylmethyl)-L-tryptophan (IMT) were developed. The developed method allowed simultaneous determination of these four impurities in 5 min. No interferences from the matrix were observed, and the method showed good sensitivity to each analyte. The method detection limit and limit of quantification in meat matrices were below 11.2 and 35.7 µg/kg, respectively.

Peak AAA fatty acid homolog contaminants present in the dietary supplement l-Tryptophan associated with the onset of eosinophilia-myalgia syndrome.

The eosinophilia-myalgia syndrome (EMS) outbreak that occurred in the USA and elsewhere in 1989 was caused by the ingestion of Showa Denko K.K. (SD) L-tryptophan (L-Trp). "Six compounds" detected in the L-Trp were reported as case-associated contaminants. Recently the final and most statistically significant contaminant, "Peak AAA" was structurally characterized. The "compound" was actually shown to be two structural isomers resulting from condensation reactions of L-Trp with fatty acids derived from the bacterial cell membrane. They were identified as the indole C-2 anteiso (AAA1-343) and linear (AAA2-343) aliphatic chain isomers. Based on those findings, we utilized a combination of on-line HPLC-electrospray ionization mass spectrometry (LC-MS), as well as both precursor and product ion tandem mass spectrometry (MS/MS) to facilitate identification of a homologous family of condensation products related to AAA1-343 and AAA2-343. We structurally characterized eight new AAA1-XXX/AAA2-XXX contaminants, where XXX represents the integer molecular ions of all the related homologs, differing by aliphatic chain length and isomer configuration. The contaminants were derived from the following fatty acids of the bacterial cell membrane, 5-methylheptanoic acid (anteiso-C8:0) for AAA1-315; n-octanoic acid (n-C8:0) for AAA2-315; 6-methyloctanoic acid (anteiso-C9:0) for AAA1-329; n-nonanoic acid (n-C9:0) for AAA2-329; 10-methyldodecanoic acid (anteiso-C13:0) for AAA1-385; n-tridecanoic acid (n-C13:0) for AAA2-385; 11-methyltridecanoic acid (anteiso-C14:0) for AAA1-399; and n-tetradecanoic acid (n-C14:0) for AAA2-399. The concentration levels for these contaminants were estimated to be 0.1-7.9 µg / 500 mg of an individual SD L-Trp tablet or capsule The structural similarity of these homologs to case-related contaminants of Spanish Toxic Oil Syndrome (TOS) is discussed.

Structure determination of disease associated peak AAA from l-Tryptophan implicated in the eosinophilia-myalgia syndrome.

The eosinophilia-myalgia syndrome (EMS) outbreak of 1989 that occurred in the USA and elsewhere was caused by the ingestion of l-Tryptophan (L-Trp) solely manufactured by the Japanese company Showa Denko K.K. (SD). Six compounds present in the SD L-Trp were reported to be case-associated contaminants. However, "one" of these compounds, Peak AAA has remained structurally uncharacterized, despite the fact that it was described as "the only statistically significant (p=0.0014) contaminant". Here, we employ on-line microcapillary-high performance liquid chromatography-electrospray ionization mass spectrometry (LC-MS), and tandem mass spectrometry (MS/MS) to determine that Peak AAA is in fact two structurally related isomers. Peak AAA1 and Peak AAA2 differed in LC retention times, and were determined by accurate mass-LC-MS to both have a protonated molecular ion (MH+) of mass 343.239Da (Da), corresponding to a molecular formula of C21H30N2O2, and possessing eight degrees of unsaturation (DoU) for the non-protonated molecule. By comparing the LC-MS and LC-MS-MS retention times and spectra with authentic synthetic standards, Peak AAA1 was identified as the intermolecular condensation product of L-Trp with anteiso 7-methylnonanoic acid, to afford (S)-2-amino-3-(2-((S,E)-7-methylnon-1-en-1-yl)-1H-indol-3-yl)propanoic acid. Peak AAA2 was determined to be a condensation product of L-Trp with decanoic acid, which produced (S)-2-amino-3-(2-((E)-dec-1-en-1-yl)-1H-indol-3-yl)propanoic acid.

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.

Meningococcemia en el contexto de una mononucleosis infecciosa / Meningoccocal disease in a patient with infectious mononucleosis

En la evaluación de los pacientes con síndrome febril, la detección de petequias asociada a un deterioro clínico importante debe orientar el diagnóstico de enfermedad meningocócica invasora. Sin embargo, algunos pacientes presentan un cuadro clínico sutil o atípico que dificulta el diagnóstico; los signos de alarma clínicos y analíticos son útiles para identificar a los niños que se beneficiarán de un tratamiento empírico precoz que mejore su pronóstico. Presentamos el caso de un niño de 3 años de edad, diagnosticado en nuestro centro de una enfermedad meningocócica invasora, insospechada por su evolución atípica, que acude al servicio de urgencias por presentar fiebre de 4 días de evolución, petequias y púrpura palpable, aunque manteniendo un buen estado general en todo momento (AU)

In the evaluation of patients with a febrile syndrome, detection of petechiae associated to an ill appearance should make us suspect an invasive meningococcal disease. Nevertheless, some patients present in a more subtle manner or with an atypical course that will make difficult the diagnosis. Clinical and analytical alarm sings could be useful to identify these children who would benefit from an early empirical treatment that improves their prognosis. We report a case of unsuspected invasive meningococcal disease because of unusual presentation in a 3-years-old boy. He came to the emergency room complaining of 4 days fever, petechiae and palpable purpura. The patient's clinical condition was all time preserved (AU)

Role of Eosinophilsin parasitic Infections

Eosinophilia; a pronounced increase of eosinophils in the blood or tissues; occurs in numerous important circumstances; like allergic diseases; parasitic infections; and cancer. Helminthic parasites are usually the common parasitic infections witch cause eosinophilia apart from two enteric protozoans; Isospora belli and Dientamoeba fragilis. Infection with helminthes parasites produces immune effector responses and in a reaction to various stimuli; eosinophils are recruited from the circulation into inflammatory foci; where they modulate immune responses via sequences of mechanisms. The defence against organisms that are too large to be phagocytosed; particularly parasitic helminthes seems to be the primary role of eosinophils. In this article; we will discuss some of the biological features of eosinophils and their role in parasitic infections

Eosinophilic fasciitis (Shulman disease).

The eosinophilic fasciitis (EF) is a rare connective tissue disease characterized by symmetrical and painful swelling with a progressive induration and thickening of the skin and soft tissues. The diagnosis of EF is often based on the association of characteristic skin or subcutaneous abnormalities and a thickened fascia with an inflammatory infiltration, mostly composed of lymphocytes and eosinophils. A peripheral eosinophilia is frequently present, but is not mandatory for the EF diagnosis. The diagnosis might be helped by a muscle magnetic resonance imaging which typically may evidence an increased signal intensity within the fascia and marked fascia enhancement after gadolinium administration at the acute phase of the disease. Differential diagnoses should be ruled out, including eosinophilia-myalgia syndrome (EMS) after L-tryprophane ingestion, hypereosinophilic syndromes (HES), systemic sclerosis, Churg-Strauss syndrome, and/or peripheral T cell lymphomas with cutaneous involvement. Due to the scarcity of the EF disease, there is no consensual therapeutic strategy. However, oral corticosteroids remain the mainstay treatment and may be associated to an immunosuppressive drug such as methotrexate in patients with morphea-like lesions or an unsatisfactory response to corticosteroids alone.

Effects and side effects associated with the non-nutritional use of tryptophan by humans.

The daily nutritional requirement for L-tryptophan (Trp) is modest (5 mg/kg). However, many adults choose to consume much more, up to 4-5 g/d (60-70 mg/kg), typically to improve mood or sleep. Ingesting L-Trp raises brain tryptophan levels and stimulates its conversion to serotonin in neurons, which is thought to mediate its actions. Are there side effects from Trp supplementation? Some consider drowsiness a side effect, but not those who use it to improve sleep. Though the literature is thin, occasional side effects, seen mainly at higher doses (70-200 mg/kg), include tremor, nausea, and dizziness, and may occur when Trp is taken alone or with a drug that enhances serotonin function (e.g., antidepressants). In rare cases, the "serotonin syndrome" occurs, the result of too much serotonin stimulation when Trp is combined with serotonin drugs. Symptoms include delirium, myoclonus, hyperthermia, and coma. In 1989 a new syndrome appeared, dubbed eosinophilia myalgia syndrome (EMS), and was quickly linked to supplemental Trp use. Key symptoms included debilitating myalgia (muscle pain) and a high peripheral eosinophil count. The cause was shown not to be Trp but a contaminant in certain production batches. This is not surprising, because side effects long associated with Trp use were not those associated with the EMS. Over 5 decades, Trp has been taken as a supplement and as an adjunct to medications with occasional modest, short-lived side effects. Still, the database is small and largely anecdotal. A thorough, dose-related assessment of side effects remains to be conducted.

Síndrome DRESS inducido por fármacos antituberculosos en un paciente con diabetes mellitus tipo 2 / Antituberculous drugs-induced DRESS syndrome in a patient with type 2 diabetes mellitus

Presentamos el caso de un paciente varón de 48 años de edad, con diagnóstico de diabetes mellitus tipo 2, no controlada, de diez años de evolución, a quien se le diagnosticó tuberculosis pulmonar mediante signos clínicos, radiográficos y cultivo en esputo positivo para Mycobacterium tuberculosis, sensible a drogas antituberculosas de primera línea. Recibió isoniacida, rifampicina, etambutol y pirazinamida. Dos meses después de iniciado el tratamiento presentó hipersensibilidad a medicamentos, con los siguientes signos y síntomas: rash dérmico generalizado, prurito generalizado, anemia Coombs positiva, eosinofilia y síntomas sistémicos, compatibles con el síndrome DRESS (drug rash with eosinophilia and systemic symptoms). Ante ello, se suspendió la medicación antituberculosa y se instaló tratamiento con antihistamínicos y corticoides sistémicos, con remisión y mejoría de síntomas. Posteriormente, recibió un esquema individualizado de tratamiento para tuberculosis consistente en medicamentos mínimamente hemato-hepatotóxicos, similar al indicado en pacientes inmunosuprimidos. Desde entonces presenta baciloscopias negativas.

A case of a 48 year-old male with uncontrolled type 2 diabetes mellitus for the past ten years who presented pulmonary tuberculosis by clinical, radiographic signs and Mycobacterium tuberculosis sputum culture, sensitive to first line treatment drugs, is reported. He received standard treatment with isoniazid, rifampicin, ethambutol, pyrazinamide showing two months later drug hypersensitivity consisting in generalized skin rash, pruritus, positive Coombs anemia, eosinophilia and systemic symptoms compatible with DRESS syndrome (drug rash with eosinophilia and systemic symptoms). The antituberculous drugs were suspended and systemic antihistaminic drugs and corticoids were administered with remission and improvement of symptoms. Afterwards individualized treatment scheme for tuberculosis consisting in minimal hemato-hepatotoxic drugs similar to those indicated to immunosuppressed patients was indicated. Baciloscopies have been negative since.

Post-epidemic eosinophilia-myalgia syndrome associated with L-tryptophan.

Eosinophilia-myalgia syndrome (EMS) is characterized by subacute onset of myalgias and peripheral eosinophilia, followed by chronic neuropathy and skin induration. An epidemic of EMS in 1989 was linked to consumption of L-tryptophan that had originated from a single source. Following the ban by the Food and Drug Administration (FDA) on the sale of L-tryptophan, the incidence of EMS declined rapidly. Moreover, no new cases have been described since the FDA ban was lifted in 2005. We report the clinical, histopathologic, and immunogenetic features of a new case of L-tryptophan-associated EMS, along with evidence of activated transforming growth factor ß and interleukin-4 signaling in the lesional skin.

Determinación de la utilidad de la espectroscopia por luz casi-infrarroja (NIRS) en el estudio de la mialgia de esfuerzo en los antebrazos de los músicos / Determination of the utility of Near-Infrared Spectroscopy (NIRS) in the study of exertional mialgia in musician’s forearms

Objetivo: Determinar si la mialgia de esfuerzo en los antebrazos de los músicos está asociada a un trastorno de irrigación u oxigenación muscular condicionado por una alteración en la presión intracompartimental (PIC). Material y método: Se estudiaron 29 músicos con mialgia de esfuerzo en antebrazos y un grupo control de 9 músicos sanos. Se midió simultáneamente la presión en el compartimento extensor superficial del antebrazo y la oxigenación tisular mediante espectroscopia con luz casi-infrarroja. Las mediciones se realizaron antes, durante y después de realizar un trabajo dinámico de flexo-extensión contra resistencia de los dedos hasta la fatiga. Resultados: El valor medio de la PIC en reposo fue de 13,22 mmHg (grupo control) y de 12,42 mmHg (grupo mialgia). La PIC post-esfuerzo fue de 17,19 mmHg y de 14,83 mmHg. Los valores de la PIC no mostraron diferencias estadísticamente significativas entre los dos grupos. Se objetivaron diferencias significativas de oxihemoglobina entre los dos grupos en la fase de recuperación. Conclusiones: La mialgia de esfuerzo podría asociarse a una alteración en la oxigenación e irrigación tisular pero sin existir indicios de estar provocado por un aumento patológico de la PIC (AU)

Aim: investigate whether exertional myalgia in musician’s forearms is a disorder associated with a deficiency on muscle irrigation/oxygenation and whether this is determined by an increased intracompartmental pressure (ICP). Material and methods: We have studied 29 musicians with forearm’s exertional myalgia and a control group of 9 healthy players. In all them the ICP, measured in the forearm superficial extensor compartment, and the tissue oxygenation, by means of near-infrared spectroscopy, was simultaneously recorded. Measurements were taken before, during and after doing dynamic fingers flexion-extension work against resistance to fatigue. Results: The mean resting ICP was 13.22 mmHg (control group) and 12.42 mmHg (myalgia group). Postexertion ICP was 17.19 mmHg and 14.83 mmHg. The PIC values showed no statistically significant differences between the two groups. Significant discernible differences were seen in the amount of oxyhemoglobin between he two groups in the recovery phase. Conclusions: Exertional myalgia seems to be associated with an alteration in tissue oxygenation and irrigation but there are no indicators of being caused by a pathological increase in ICP (AU)

AHR activation by tryptophan--pathogenic hallmark of Th17-mediated inflammation in eosinophilic fasciitis, eosinophilia-myalgia-syndrome and toxic oil syndrome?

The aryl-hydrocarbon-receptor (AHR) is involved as receptor and transcription factor in dioxin toxicity. Recently, its role in Th17-mediated autoimmunity and autoinflammation has been described, yet a disease-associated AHR ligand is still elusive. L-tryptophan and its metabolites are assumed to trigger the autoinflammatory disorders eosinophilic fasciitis, eosinophilia-myalgia-syndrome and toxic oil syndrome. Since L-tryptophan and metabolites are well known as AHR ligands we hypothesize that it is their interaction with AHR that induces Th17 cell differentiation and autoinflammation in these disorders. This, for the first time would link disease-causing environmental factors to a well-defined cellular receptor and the subsequent pathogenic pathway.

Manifestaciones cutáneas del síndrome tóxico por aceite de colza adulterado / Skin Manifestations of Toxic Syndrome Due to Denatured Rapeseed Oil

En este artículo se efectuó una amplia descripción clínico-patológica y cronológica de las manifestaciones cutáneas del síndrome tóxico por aceite de colza adulterado o síndrome tóxico por aceite. Esta nueva enfermedad se produjo en España en 1981, debida a la ingesta de aceite de colza destinado a uso industrial, que había sido coloreado con anilinas y posteriormente decolorado de forma fraudulenta y vendido como aceite de oliva. En total se produjeron unos 20.000 casos y unos 400 fallecimientos. Existía un predominio por el sexo femenino, sobre todo en la fase tardía. En la fase aguda las manifestaciones cutáneas predominantes fueron exantemas toxoalérgicos, con un patrón dermatopatológico de erupción alérgica urticariforme. Alrededor de un 25% de los casos desarrolló posteriormente un aspecto edematoso de la piel, con trastornos de la pigmentación, que demostró estar relacionado con mucinosis dérmica. Finalmente se produjo un cuadro esclerodermiforme peculiar, que tendió a mejorar de forma espontánea. La presencia constante de mastocitos en todas las biopsias y el desarrollo de mastocitosis en varios pacientes sugirieron un papel importante del mastocito en la patogenia del cuadro, que luego ha sido ratificada en otros procesos esclerodermiformes. En 1989 apareció en EE.UU. el síndrome mialgia-eosinofilia, relacionado con sustancias tóxicas presentes en suplementos alimentarios de triptófano y que compartía muchos aspectos con el síndrome tóxico por aceite. Esto corroboró la existencia de mucinosis y cuadros esclerodermiformes de origen tóxico (AU)

This article offered an extensive description of the clinical and pathological features and time-course of the skin manifestations of toxic syndrome caused by denatured rapeseed oil, also known as toxic oil syndrome. This new condition occurred in Spain in 1981 and was due to the ingestion of rapeseed oil intended for industrial use that had been denatured with anilines and subsequently refined and sold fraudulently as olive oil. In total, 20 000 cases and 400 deaths were reported. The disease affected mainly women, particularly in the late stages. In the acute phase, the predominant skin manifestations were toxic-allergic rashes reminiscent of allergic urticaria in the dermatopathologic study. In approximately 25% of cases, the patients’ skin subsequently took on an edematous appearance, with pigmentary abnormalities shown to be related to cutaneous mucinosis. Finally, a characteristic sclerodermatous condition would develop that tended to improve spontaneously. The constant presence of mast cells in all biopsies and the development of mastocytosis in several patients pointed to an important role for these cells in the pathogenesis of the condition. This was subsequently confirmed in other sclerodermatous processes. In 1989, eosinophilia-myalgia syndrome caused by toxins present in tryptophan food supplements was reported in the United States. This syndrome resembled toxic oil syndrome in many ways and demonstrated that mucinosis and toxic sclerodermatous processes do exist (AU)

Immunogenetic risk and protective factors for the development of L-tryptophan-associated eosinophilia-myalgia syndrome and associated symptoms.

OBJECTIVE: To assess L-tryptophan (LT) dose, age, sex, and immunogenetic markers as possible risk or protective factors for the development of LT-associated eosinophilia-myalgia syndrome (EMS) and related clinical findings. METHODS: HLA-DRB1 and DQA1 allele typing and Gm/Km phenotyping were performed on a cohort of 94 white subjects with documented LT ingestion and standardized evaluations. Multivariate analyses compared LT dose, age, sex, and alleles among groups of subjects who ingested LT and subsequently developed surveillance criteria for EMS, developed EMS or characteristic features of EMS (EMS spectrum disorder), or developed no features of EMS (unaffected). RESULTS: Considering all sources of LT, higher LT dose (odds ratio [OR] 1.4, 95% confidence interval [95% CI] 1.1-1.8), age >45 years (OR 3.0, 95% CI 1.0-8.8), and HLA-DRB1*03 (OR 3.9, 95% CI 1.2-15.2), DRB1*04 (OR 3.9, 95% CI 1.1-16.4), and DQA1*0601 (OR 13.7, 95% CI 1.3-1.8) were risk factors for the development of EMS, whereas DRB1*07 (OR 0.12, 95% CI 0.02-0.48) and DQA1*0501 (OR 0.23, 95% CI 0.05-0.85) were protective. Similar risk and protective factors were seen for developing EMS following ingestion of implicated LT, except that DRB1*03 was not a risk factor and DQA1*0201 was an additional protective factor. EMS spectrum disorder also showed similar findings, but with DRB1*04 being a risk factor and DRB1*07 and DQA1*0201 being protective. There were no differences in sex distribution, Gm/Km allotypes, or Gm/Km phenotypes among any groups. CONCLUSION: In addition to the xenobiotic dose and subject age, polymorphisms in immune response genes may underlie the development of certain xenobiotic-induced immune-mediated disorders, and these findings may have implications for future related epidemics.

Eosinophilic myositis in calpainopathy: could immunosuppression of the eosinophilic myositis alter the early natural course of the dystrophic disease?

An 11-year-old girl with a calpain-3 gene (CAPN-3) mutation and eosinophilic myositis on muscle biopsy had high serum CK levels and eosinophil counts which showed spontaneous fluctuations. After commencement of immunosuppressive therapy reciprocal changes occurred in response to alterations in doses of the medications. Subacutely evolving and spreading muscle weakness developed during tapering of the immunosuppressive medications. These observations suggest that either the occurrence of eosinophilic myositis or the withdrawal of the immunosuppressive treatment may have accelerated the clinical course of the calpainopathy in this case. The positive effect of immunosuppressive therapy might have implications for the management of calpainopathy with an inflammatory component.