[Progressive human viral encephalitis associated to a bat bite]. / Encefalitis rábica, consecutiva a mordedura de murciélago.

INTRODUCTION: Human rabies is a rapidly progressive encephalitis that is transmitted by the bites of an infected mammal. METHODS: In June 2004, a male patient was admitted to a hospital emergency department after a 5-days history of progressive right arm pain, paresthesias and muscle weakness. He reported contact with a sick bat 5 weeks before admission. He suffered steady neurologic decline with fever, confusion, disorientation, hydrophobia and aerophobia the following day. The patient died two days later. RESULTS: Postmortem histopathology showed perivascular mononuclear infiltration and extensive neuronolysis. When the fluorescent antibody technique was applied, most residual neurons were infected by the rabies virus. Lyssavirus isolation was achieved in a murine neuroblastoma cell culture. A nested reverse transcription polymerase chain reaction was positive in the patient's cerebrospinal fluid as well as the tissues of the bat Lasionycteris noctivagans. CONCLUSIONS: Clinicians should suspect rabies when unexplained progressive encephalitis is observed.

Encefalitis rábica, consecutiva a mordedura de murciélago / Progressive human viral encephalitis associated to a bat bite

Introducción. La rabia humana es una encefalitis rápidamente progresiva, transmitida por la mordedura de un mamífero infectado. Métodos. En junio de 2004 un enfermo fue hospitalizado en el servicio de urgencias después de 5 días con dolor del brazo derecho, parestesias y debilidad muscular. Relató haber tenido contacto con un murciélago enfermo 5 semanas antes del internamiento. Los días siguientes hubo deterioro neurológico progresivo, fiebre, confusión, desorientación, hidrofobia y aerofobia. Murió después de 2 días. Resultados. La histopatología post mórtem, mostró el infiltrado perivascular de células mononucleares y neuronolisis intensa; al aplicar la técnica de los anticuerpos fluorescentes las neuronas residuales estaban infectadas por el virus rábico. Se logró aislar Lyssavirus en un cultivo celular de neuroblastoma murino; la prueba de transcripción inversa "anidada" de la reacción en cadena de la polimerasa resultó positiva tanto en el líquido cefalorraquídeo del enfermo como en los tejidos del murciélago Lasionycteris noctivagans. Conclusiones. Los clínicos deben sospechar la rabia al observar la encefalitis progresiva de causa inexplicada

Introduction: Human rabies is a rapidly progressive encephalitis that is transmitted by the bites of an infected mammal. Methods. In june 2004, a male patient was admitted to a hospital emergency department after a 5-days history of progressive right arm pain, paresthesias and muscle weakness. He reported contact with a sick bat 5 weeks before admission. He suffered steady neurologic decline with fever, confusion, disorientation, hydrophobia and aerophobia the following day. The patient died two days later. Results. Postmortem histopathology showed perivascular mononuclear infiltration and extensive neuronolysis. When the fluorescent antibody technique was applied, most residual neurons were infected by the rabies virus. Lyssavirus isolation was achieved in a murine neuroblastoma cell culture. A nested reverse transcription polymerase chain reaction was positive in the patient's cerebrospinal fluid as well as the tissues of the bat Lasionycteris noctivagans. Conc1usions. Clinicians should suspect rabies when unexplained progressive encephalitis is observed

Miliary tuberculosis involving the central nervous system.

A woman with chronic systemic lupus erythematosus (SLE) was treated with prednisone, and developed an acute febrile neuroinfection. The magnetic resonance images (MRI) showed miliary micronodular lesions distributed diffusely within the central nervous system and lungs. Lumbar puncture showed pleocytosis with predominance of polymorphonuclear leukocytes, hypoglycorrhachia, elevated proteins and smears positive for acid-fast bacilli. The diagnosis was confirmed by culture of Mycobacterium tuberculosis in the cerebrospinal fluid and bronchial biopsy tissue. She was treated with ethambutol, rifampin, isoniazid and pyrazinamide. MRI taken one month later showed significant improvement, but leg weakness persisted. Epidemiologic research showed her uncle with cavitary tuberculosis as the source of infection. He was also treated with combined antituberculous chemotherapy.

Progressive multifocal leukoencephalopathy: clinical description and demonstration of the causal agent.

A 40 year old man with AIDS had memory deficit and visual impairment. The brain magnetic resonance images showed abnormalities in the white matter not enhanced with gadolinium. JC-virus DNA was detected in the cerebrospinal fluid. He died after a few weeks of progressive neurologic deterioration. Histologic examination showed changes compatible with progressive multifocal leukoencephalopathy. Polyoma virus etiology was confirmed by immunostaining of brain tissue sections and electron microscopy of infected oligodendrocytes.

Progressive multifocal leukoencephalopathy: clinical description and demostration of the casual agent

Un hombre de 40 años con SIDA, presentó déficit de la memoria y trastornos visuales. Las imágenes cerebrales de resonancia magnética mostraron anormalidades de la sustancia blanca que no fueron realzadas por el gadolinio. El ADN del virus JC se detectó en el líquido cefaloraquídeo y después de pocas semanas de un deterioro neurológico progresivo el enfermo murió. En el estudio histológico se demostraron lesiones compatibles con el diagnóstico de leucoencefalopatía multifocal progresiva. El poliomavirus causal se confirmó por la inmunotinción de los cortes del tejido cerebral y por la microscopia electrónica de los oligodendrocitos infectados

A 40 year old man with AIOS had memory deficit and visual impairment. The brain magnetic resonance images showed abnormalities in the white matter not enhanced with gadolinium. JC-virus ONA was detected in the cerebrospinal fluid. He died after a few weeks of progressive neurologic deterioration. Histologic examination showed changes compatible with progressive multifocal leukoencephalopathy. Polyoma virus etiology was confirmed by immunostaining of brain tissue sections and electron microscopy of infected oligodendrocytes

Miliary tuberculosis involving the central nervous system

Una mujer con lupus eritematoso sistémico fue tratada con prednisona y desarrolló una neuroinfección febril y aguda. Las imágenes de resonancia magnética (RM) mostraron lesiones miliares micronodulares distribuidas difusamente en el sistema nervioso central y los pulmones. La punción lumbar demostró pleocitosis con predominio de leucocito s polimorfonudeares, hipoglucorraquia, proteínas elevadas y los frotis fueron positivos para bacilos acidorresistentes. El diagnóstico se confirmó por cultivo de Mycobacterium tuberculosis en el líquido cefalorraquídeo y en el tejido de la biopsia endobronquial. Fue tratada con etambutol, rifampicina, isoniacida y pirazinamida. Las RM tomadas un mes después mostraron mejoria significativa, aunque persistió la debilidad de las piernas. La investigación epidemiológica demostró que su tío afectado de tuberculosis cavitada fue la fuente de la infección, y fue tratado también con quimioterapia antituberculosa combinada

A woman with chronic systemic lupus erythematosus (SLE) was treated with prednisone, and developed an acute febrile neuroinfection. The magnetic resonance images (MRI) showed miliary micronodular lesions distributed diffusely within the central nervous system and lungs. Lumbar puncture showed pleocytosis with predominance of polymorphonuclear leukocytes, hypoglycorrhachia, elevated proteins and smears positive for acid-fast bacilli. The diagnosis was confirmed by culture of Mycobacterium tuberculosis in the cerebrospinal fluid and bronchial biopsy tissue. She was treated with ethambutol, rifampin, isoniazid and pyrazinamide. MRI taken one month later showed significant improvement, but leg weakness persisted. Epidemiologic research showed her uncle with cavitary tuberculosis as the source of infection. He was also treated with combined antituberculous chemotheraphy

El espectro clínico-epidemiológico de la histoplasmosis pulmonar: Avances recientes y perspectivas futuras / The clinical-epidemilogical spectrum of pulmonary histoplasmosis. recent advances and future perspectives

La histoplasmosis es una micosis endémica en todos los continentes excepto en la Antártida, causado por el hongo dimórfico Histoplasma capsulatum, var. capsulatum. La infección pulmonar primaria generalmente es asintomática, o una enfermedad febril, autolimitada. Se han reconocido tres categorías diferentes: pulmonar aguda, pulmonar crónica y diseminada progresiva, con ataque al sistema fagocítrico. Las pruebas serológicas, los cultivos del hongo y la histopatología son útiles para establecer el diagnóstico. Los tejidos deben ser teñidos con plata para visualizar las levaduras. El sistema del hemocultivo de lisiscentrifugación, puede detectar al H. capsulatum de una a dos semanas. Existe un procedimiento para la detección del antígeno, muy útil para el seguimiento de la terapia, incluyendo a los pacientes infectados por el virus de la inmunodeficiencia humana (VIH). La terapia antifúngica no está indicada en la mayoría de los enfermos, aunque algunos tienen una enfermedad prolongada (> 3 semanas). El diagnóstico temprano y un tratamiento oportuno con enfotericina B o itraconazol, puede acelerar la resolución de la enfermedad. El flunconazol es una elección razonable en la terapia supresiva crónica

Update on sporotrichosis.

Sporotrichosis is endemic in temperate and tropical regions of the world, including Australia. Although uncommon, it is frequently encountered in Northern Australia, especially in Queensland. All ages are affected, although most cases occur from occupational exposure to vegetation or soil. This article reviews the cause, diagnosis and treatment options of this fungal disease which affects the skin and is often misdiagnosed. It classically presents in gardeners, especially those handling roses.

[The immunology of cholera and the molecular biology of cholera toxin. Recent progress and future perspectives]. / La inmunología del cólera y la biología molecular de la toxina colérica. Progresos recientes y perspectivas futuras.

Vibrio cholerae has recently called the attention of researchers due to its strong immunogenicity and also because it serves as coadjunct immunomodulator of the immune response of the intestinal mucosae for the mixed added antigens as well as for those covalently linked to the toxin. The immunopathogeny of cholera is a complex phenomenon. This article presents the preliminary results of experiments conducted with laboratory rats in order to find the IgA intestinal response of rodents and humans.

[Cellular immunity and vaccination against cutaneous leishmaniasis. Recent progress and prospects]. / La inmunidad celular y la vacunación contra la leishmaniasis cutánea. Progresos recientes y perspectivas.

Review of leishmaniasis immunopathogenesis, the models in the laboratory animals, and the last advances in the experimental vaccine administration. In recent years, there have been important progresses that have contributed substantially to classify the role of the interleukins and other chemical mediators in the immunologic response. All these advances open the door to the production of better and more immunogenic vaccines, that in a near future will be employed advantageous in the human beings.

[Cholera immunology and the molecular biology of cholera toxin. Recent progress and future prospects]. / La inmunología del cólera y la biología molecular de la toxina colérica. Progresos recientes y perspectivas futuras.

Cholera toxin (CT) and the analogous heat-labile enterotoxin (LT) from Escherichia coli have several immunomodulating effects that might explain their adjuvant action in stimulating secretory mucosal IgA after oral immunization. In mice experimental model, these effects include: enhanced antigen presentation by macrophages and other cell types; promotion of isotype differentiation in B cells leading to increased IgA formation; and other important effects on T cell proliferation and lymphokine production. The adjuvant activity is linked to the ADP-ribosylating action of CT with increased cyclic AMP formation in the affected cell, and thus it may be difficult to eliminate the enterotoxic activity without loss of adjuvanticity. However, both CT and its non-toxic B subunit moiety (CTB) have been shown to enhance the mucosal immune response to various epitopes or antigens covalently linked to these molecules. This now give promise that those antigens could become a useful vehicle to facilitate the induction of specific secretory IgA response to a broad range of antigens for human vaccination against cholera and other enteric infections.

[Coccidioidomycosis in children]. / La coccidioidomicosis en los niños.

Coccidioides immitis is the cause of coccidioidomycosis, the fungus has been found extensively in the Southwestern United States, and Mexico, and certain areas of Central and South America. Some climatic conditions, such as hot summers with little winter frost, combined with arid, alkaline soils produce ideal circumstances for preservation of the arthroconidia. Children and other human groups are infected by dustbone arthroconidia or by contact with infected soils. There has been limited epidemics of infantile coccidioidomycosis, however, only very few have been verified as to the source of the outbreak by the soil-culture of the fungus. The primary pulmonary infection is usually asymptomatic, but it may resemble influenza with cough, fever, and chest pain. Chronic pulmonary lesions are rare in children. Erythema multiforme an erythema nodosum have been described, namely in females. Arthralgias occurs in some patients. The disseminated form is similar to tuberculosis with lungs, lymph nodes, bones, joints, abdominal organs and skin being the frequently affected sites. Meningitis and limited dissemination to one of few sites is more common in mexican children than adults. Serologic tests are very useful in moderate to severe illnesses. Precipitins can be easily detected by immunodifusion. Higher and persistent complement fixation titers are observed in severe and disseminated infection. Conversion of a skin test with coccidioidin or spherulin from negative to positive strongly suggest coccidioidomycosis. Most cases do not require treatment, but amphotericin B or ketoconazol, are the standard therapy in severe pulmonary disease or disseminated forms, and surgery has been advocated for localized, persistent or drug-resistant, progressive lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

[Rabies as a public health problem]. / La rabia como problema de salud pública.

Rabies virus belong to the family Rhabdoviridae; it has a coiled RNA core surrounded by a bullet-shaped envelop, covered with glycoproteins surface projections. After entry into a new host in the bite site, the virus multiplies in muscle cells and it spreads through neural pathways, without stimulating a protective host immune-response. Transmission depends on simultaneous delivery of virus to the salivary gland and the limbic system of the brain, which is the cause of the animal fury and biting tendency. In México, rabies continues to be a serious health and economic problem, and urban rabies still predominates with a large number of human and animal cases recorded yearly. A total of 426 human deaths were reported between 1978 and 1983. Over 9,069 cases of animal rabies were reported in 1986 and 50,000 patients required antirabies postexposure vaccinations. Infected animals can be identified by demonstration of specific fluorescence in brain tissue. A dog or cat which has bitten a human should be captured and observed by a veterinarian for 15 days. The immediate objective of postexposure treatment is to prevent virus from entering and damaging neural tissue, therefore, promptness is essential. All wounds should be thoroughly cleared with soap and water concurrent use of both passive and active immunization provides optimal therapy. Wherever possible, human rather than equine products should be used for passive immunization, and Fuenzalida's nerve tissue rabies vaccine should be used for active protection. Paediatricians should urge parents to caution children attempting to get stray or wild animals as pets. Domestic dogs and cats should be thoroughly vaccinated.

[Invasive amebiasis as a public health problem]. / La amibiasis invasora como problema de salud pública.

Amebiasis, an infection of humans with the protozoan Entamoeba histolytica, has a wide distribution in Mexico. The lumenal, asymptomatic infection, as measured by the presence of cysts in stools has been recorded from 2.4% at Ometepec, Guerrero to over 55% at Mixquic, D.F., but only a small percentage of those having intestinal infection will develop invasive amebiasis, the main clinical forms being dysentery and liver abscess. In Mexico City, from 0.8 up to 14% of cases of acute diarrhoea in children requiring hospitalization were found to be associated with E. histolytica. Serological surveys for antibodies, suggest that approximately 5.98% of people had intestinal mucosal or liver invasion, but amebic dysentery may be five to 50 times more frequent than liver abscess, namely in children. Amebiasis may cause death when it manifests itself as fulminating colitis or liver abscess. Lethality in adults has been estimated to be around 0.2 to 2%, but in children with liver abscess it may be 1.1 to 26%. In addition to being a potentially lethal disease, it has important socioeconomic consequences, because incapacitating infections are rather frequent in wage-earning adult males requiring several weeks of hospitalization and from two to three months for full recovery. In Mexico, amebiasis has been more closely associated with poverty and low levels of sanitation than to climate, and in view of the high rates of morbidity and mortality caused by E. histolytica, more research into better and cheaper methods of diagnosis, treatment and prevention is clearly necessary plus a substantial improvement in control strategies.