Hepatotoxicidad por talidomida: caso clínico y revisión de la literatura / Hepatotoxicity by thalidomide: case report and literature review

La talidomida fue desarrollada e introducida al mercado por los laboratorios Grünenthal en 1953, siendo usada principalmente como sedante y también para el tratamiento de las náuseas durante el embarazo. Los informes dan cuenta de aproximadamente 10.000 niños que nacieron con focomelia, dando lugar a la denominada "tragedia de la talidomida", que obligó a su retiro del mercado en 1962. Luego de casi 60 años, es nuevamente utilizada en otros campos de la medicina, entre ellos, para el tratamiento de la lepra y del mieloma múltiple, debido a sus propiedades antinflamatorias, inmunomoduladoras y antiangiogénicas, con expresas advertencias sobre su utilización durante el embarazo; no obstante, con su nuevo uso han sido reportados múltiples efectos adversos, entre los que se encuentra la hepatitis aguda o crónica inducida por este fármaco. Se presenta el caso de una paciente de 34 años con lepra, que estaba en tratamiento con talidomida desde hacía 4 años para combatir las lesiones de piel asociadas a esta enfermedad. Presentó malestar general, vómito, pérdida de peso, artralgias, ictericia, edemas de miembros inferiores, ascitis, coluria y acolia. Se sospechó toxicidad por talidomida, por lo que se suspendió su uso, y se trató con ácido ursodesoxicólico y N-acetilcisteína con mejoría sintomática y de laboratorio, desde la primera semana hasta los 41 días de seguimiento. Las entidades clínicas para las cuales se aprobó talidomida en 1998, pueden traer nuevos problemas y desafíos clínicos. Este caso muestra hepatotoxicidad crónica por talidomida, situación que hasta el momento no se había reportado en la literatura.

Thalidomide was developed and introduced to the market by Grünenthal laboratories in 1953, being used mainly as a sedative and also for the treatment of nausea during pregnancy. Reports give account of approximately 10,000 children who were born with phocomelia, giving rise to the so-called "thalidomide tragedy", which forced its withdrawal from the market in 1962. After almost 60 years, it is usedagain in other fields of medicine, including the treatment of leprosy and multiple myeloma, due to its anti-inflammatory, immunomodulatory and anti-angiogenic properties, with clear warnings about its use during pregnancy; however, multiple adverse effects have been reported in patients with leprosy and multiple myeloma, including acute or chronic hepatitis. We present the case of a 34-year-old patient with leprosy, who had been on thalidomide therapy for 4 years to treat skin lesions associated with this disease. She presented general malaise, vomiting, weight loss, arthralgia, jaundice, lower limb edema, ascites, choluria and acholia. Thalidomide toxicity was suspected, so its use was suspended, and treatment with ursodeoxycholic acid and N-acetylcysteine was initiated, with symptomatic and laboratory improvement from the first week up until 41 days of follow-up. The new range of medical conditions for which thalidomide was approved for in 1998 may bring clinical challenges. This case shows chronic hepatotoxicity due to thalidomide, a situation that had not been reported previously in the literature.

Evaluación del método de Petroff modificado con solución salina para el diagnóstico de micobacterias en el sistema Bact/Alert 3D / Assessment of Petroff method modified with saline solution for the diagnosis of mycobacteria in Bact/Alert 3D system

Introducción: Existen diferentes métodos de descontaminación de muestras pulmonares para el diagnóstico de micobacterias. El Programa Nacional de Control de Tuberculosis recomienda el método de Petroff modificado con solución salina, pero no existen evidencias documentadas que avalen este método. Objetivo: Evaluar el método de Petroff modificado con solución salina para el diagnóstico de micobacterias en el sistema Bact/Alert 3D. Métodos: Se realizó un estudio observacional analítico de pruebas diagnósticas utilizando 100 muestras pulmonares recibidas en el Laboratorio Nacional de Referencia e Investigaciones de Tuberculosis, Lepra y Micobacterias del Instituto Pedro Kourí, abril 2016 enero 2017. La muestra se dividió en 3 alícuotas y se descontaminaron mediante 3 métodos; luego se inocularon en los medios de cultivo sólido y líquido. Se compararon los resultados del cultivo en cuanto: tiempo de detección de crecimiento, tasa de contaminación, por ciento de positividad, además se calcularon indicadores de desempeño. Resultados: Al comparar el método Petroff modificado con solución salina con el Petroff modificado con solución fosfato en Löwenstein Jensen, el tiempo de detección de crecimiento, por ciento de positividad y la tasa de contaminación se comportaron de forma similar y la sensibilidad (93,75 por ciento), concordancia (96,47 por ciento) e índice de Youden (0,91) fueron elevadas. Al compararlo el Petroff modificado con solución salina con el N-Acetil-L-Cisteína, las variables no mostraron diferencias significativas y los Indicadores de Desempeño se comportaron por encima del 93 por ciento, para el medio sólido y líquido. Conclusiones: Los resultados avalan la continuidad del uso del Petroff modificado con solución salina como método de descontaminación de las muestras pulmonares en la red de laboratorios de Cuba y como alternativa en el pretratamiento de las muestras para el medio líquido (Bact/Alert 3D), además constituye un soporte para el Programa Nacional de Control de Tuberculosis(AU)

Introduction: There are different decontamination methods of pulmonary samples for the diagnosis of mycobacteria. The National Program for the Control of Tuberculosis recommends Petroff method modified with saline solution; but there are not documented evidences that endorse it. Objective: Assess Petroff method modified with saline solution for the diagnosis of mycobacteria in Bact / Alert 3D system. Methods: An observational analytic study of diagnostic tests was conducted; there were used 100 pulmonary samples received in the National Laboratory of References and Researches of Tuberculosis, Leprosy and Mycobacteria of Pedro Kourí Institute, from April 2016 to January 2017. The sample was divided in 3 aliquots and those were decontaminated using 3 methods; then, they were inoculated in the solid and liquid culture means. Cultures´ results were compared according to: growth's detection time, contamination rate, percent of positivity; in addition, performance indicators were calculated. Results: When comparing Petroff method modified with saline solution with Petroff method modified with phosphate solution in Löwenstein Jensen, the growth's detection time, the percent of positivity and the rate of contamination behaved similarly, and sensitivity (93,75percent), concordance (96,47percent) and Youden´s index (0,91) were high. When the Petroff method modified with saline solution was compared with N-Acetil-L- Cisteina, the variables did not show significative differences and the behaviour indicators were over 93percent for the solid and liquid mean. Conclusions: The results endorse the continuity of the use of Petroff method modified with saline solution as a decontamination method of pulmonary samples in the network of Cuban laboratories and as alternative to the pre-treatment of the samples for the liquid mean (Bact/Alert 3D); it also constitutes a support for the National Program for the Control of Tuberculosis(AU)

N-acetylcysteine in dermatology.

N-acetylcysteine is a mucolytic drug which is commonly used as an antidote for acetaminophen toxicity. It is a thiol compound, which acts as a donor of cysteine, leading to replenishment of glutathione and thus acts as an antioxidant. It also has anti-inflammatory effects, alters the levels of neurotransmitters, inhibits proliferation of fibroblasts and keratinocytes and causes vasodilatation. Due to these actions, n-acetylcysteine has found use in several dermatologic conditions in systemic and topical form. The drug has been used as an adjuvant in the management of conditions such as toxic epidermal necrolysis, drug hypersensitivity syndrome, trichotillomania, skin picking disorders and onychotillomania, ichthyoses, contact dermatitis, atopic dermatitis, melasma, pseudoporphyria, connective tissue diseases, wound healing and alopecia. It also has a role in protection from radiation-induced skin damage including photo-ageing, photocarcinogenesis and radiation dermatitis. Most indications in dermatology are supported by case reports, small case series and small trials. Higher quality of evidence is needed for its wider use. The drug is cheap and is generally safe with few adverse effects. Thus a greater role is possible for use of n-acetylcysteine in various skin conditions. This review explores the various uses of n-acetylcysteine in the field of dermatology, the evidence supporting the same, the possible mechanisms of action and the adverse effects of the drug.

Induction of cross-priming of naive CD8+ T lymphocytes by recombinant bacillus Calmette-Guerin that secretes heat shock protein 70-major membrane protein-II fusion protein.

Because Mycobacterium bovis bacillus Calmette-Guérin (BCG) unconvincingly activates human naive CD8(+) T cells, a rBCG (BCG-70M) that secretes a fusion protein comprising BCG-derived heat shock protein (HSP)70 and Mycobacterium leprae-derived major membrane protein (MMP)-II, one of the immunodominant Ags of M. leprae, was newly constructed to potentiate the ability of activating naive CD8(+) T cells through dendritic cells (DC). BCG-70M secreted HSP70-MMP-II fusion protein in vitro, which stimulated DC to produce IL-12p70 through TLR2. BCG-70M-infected DC activated not only memory and naive CD8(+) T cells, but also CD4(+) T cells of both types to produce IFN-gamma. The activation of these naive T cells by BCG-70M was dependent on the MHC and CD86 molecules on BCG-70M-infected DC, and was significantly inhibited by pretreatment of DC with chloroquine. Both brefeldin A and lactacystin significantly inhibited the activation of naive CD8(+) T cells by BCG-70M through DC. Thus, the CD8(+) T cell activation may be induced by cross-presentation of Ags through a TAP- and proteosome-dependent cytosolic pathway. When naive CD8(+) T cells were stimulated by BCG-70M-infected DC in the presence of naive CD4(+) T cells, CD62L(low)CD8(+) T cells and perforin-producing CD8(+) T cells were efficiently produced. MMP-II-reactive CD4(+) and CD8(+) memory T cells were efficiently produced in C57BL/6 mice by infection with BCG-70M. These results indicate that BCG-70M activated DC, CD4(+) T cells, and CD8(+) T cells, and the combination of HSP70 and MMP-II may be useful for inducing better T cell activation.

Thalidomide resistance is based on the capacity of the glutathione-dependent antioxidant defense.

Thalidomide as an effective treatment for multiple myeloma and leprosy has also caused birth defects in thousands of children five decades ago particularly in Europe. Thus its use in humans remains limited. The rapid and fatal approval of thalidomide at that time ultimately was a consequence of the sole use of thalidomide-insensitive species in animal toxicity tests. Here, we aimed at elucidating the molecular basis for the resistance of mice to thalidomide teratogenicity. By using hydroethidine staining we demonstrate that thalidomide induces the formation of superoxide in embryonic fibroblasts of thalidomide-sensitive species but not in those of mice. As determined by trypan blue staining, scavenging of superoxide prevents thalidomide-induced apoptosis, a marker for thalidomide teratogenicity. Mouse embryonic fibroblasts are found to have higher glutathione levels than those of sensitive species and can be sensitized for thalidomide by glutathione depletion with diethyl maleate or diamide. Accordingly, experimental increase of glutathione levels in human embryonic fibroblasts by adding N-acetyl cysteine or glutathione ethyl ester to the culture medium counteracts thalidomide-induced apoptosis. Finally, we show that thalidomide-induced molecular pathology downstream of superoxide is essentially identical in human and sensitized mouse embryonic fibroblasts. In conclusion, thalidomide-resistance is based on the capacity of the glutathione-dependent antioxidant defense. We provide a basis to pharmacologically overcome the limitations of thalidomide use at humans and describe substantial differences between human and mouse embryonic cells regarding the protection against oxidative stress.

Oxidative-stress-induced T lymphocyte hyporesponsiveness is caused by structural modification rather than proteasomal degradation of crucial TCR signaling molecules.

In several human pathologies (e.g. cancer, rheumatoid arthritis, AIDS and leprosy) oxidative stress induces T cell hyporesponsiveness. Hyporesponsive T cells often appear to display impaired expression of some (e.g. TCR-zeta, p56(lck) and LAT) but not all (e.g. TCR-alphabeta and CD3-epsilon) crucial TCR-proximal signaling molecules but the underlying mechanisms have as yet not been identified. Using an in vitro system for oxidative-stress-induced T cell hyporesponsiveness we here report two sequential effects of oxidative stress on TCR signaling molecules: protein alterations and proteasomal degradation. We have identified the C-terminal part of TCR-zeta and the membrane-proximal domain of p56(lck) as potential targets for modifications induced by reactive oxygen species. Oxidative-stress-exposed proteins were differentially susceptible to proteasomal degradation: whereas modified TCR-zeta was relatively resistant, reactive oxygen species (ROS)-altered LAT and p56(lck) were much more susceptible. Importantly, we found that T cell hyporesponsiveness best correlated with ROS-dependent protein alteration since inhibition of proteasomal degradation did not restore function. Finally, our data provide an explanation for the paradox of reduced TCR-zeta signals combined with unaltered TCR-alphabeta and CD3-epsilon expression levels: the TCR-zeta chain in hyporesponsive T cells is still expressed but no longer detectable by certain mAb recognizing ROS-sensitive epitopes.

Pot shots.

AIDS: Certain HIV drugs have significant side effects. There have been reports from Europe that some hemophiliacs using protease inhibitors suffered from spontaneous bleeding. Clofazimine, sold as Lamprene, has been shown to cause harm when used with clarithromycin and ethambutol to treat MAC. Lamprene may cause internal bleeding, nausea, diarrhea, dizziness, drowsiness, and dry skin. Results of a Taiwanese trial of thymosin-alpha indicate that it did not help treat Hepatitis B in a statistically significant way. NAC, an antioxidant, may increase glutathione levels and indirectly increase survival.^ieng