Caracterización molecular de los aislamientos de Cryptococcus neoformans de pacientes con HIV, Guayaquil, Ecuador / Molecular characterization of Cryptococcus neoformans isolates from HIV patients, Guayaquil, Ecuador

Resumen Introducción. La neurocriptococosis es una infección fúngica oportunista que representa un alto costo en vidas humanas y para la economía de los países. Sus agentes causales, las especies del complejo Cryptococcus neoformans/Cryptococcus gattii, tienen una fase sexuada y otra asexuada, cuatro serotipos principales y siete variedades moleculares con diferencias clínico-epidemiológicas, fenotípicas y de sensibilidad a los antifúngicos. Objetivo. Caracterizar molecularmente los aislamientos clínicos de C. neoformans de Guayaquil, Ecuador. Materiales y métodos. Se determinó el tipo de apareamiento, el serotipo y la variedad molecular mediante reacción en cadena de la polimerasa y análisis del polimorfismo de los fragmentos de restricción de 27 aislamientos levaduriformes previamente identificados como C. neoformans mediante métodos convencionales. Los aislamientos fueron recuperados del líquido cefalorraquídeo de pacientes con síndrome neurológico seropositivos para HIV, internados en el Hospital de Infectología "Dr. José Daniel Rodríguez Maridueña", entre diciembre de 2013 y enero de 2015. Resultados. Se demostró el amplio predominio de C. neoformans del serotipo A, MATα y el genotipo VNI entre los aislamientos estudiados. Conclusiones. Estos datos son similares a los obtenidos en otros países y son los primeros de su tipo en Guayaquil, Ecuador, por lo cual constituyen un aporte importante al conocimiento de la criptococosisen esta ciudad.

Abstract Introduction: Neurocryptococcosis is an opportunistic fungal infection that represents a high cost in human lives and for the economy of countries. Its causative agent, the Cryptococcus neoformans/Cryptococcus gattiispecies complex, has a sexual and an asexual phase, four major serotypes and seven molecular varieties with phenotypic, clinical-epidemiological and antifungal susceptibility differences. Objective: To characterize by molecular methods clinicalisolates of C. neoformans from Guayaquil, Ecuador. Materials and methods: We determined mating types, serotypes and molecular varieties by PCR and RFLP in 27 yeast isolates previously identified as C. neoformans by conventional methods. The isolates were recovered from cerebrospinal fluid of HIV seropositive patients with neurological syndrome admitted at "Dr. José Daniel Rodríguez Maridueña" Hospital from December, 2013, to January, 2015. Results: We established a wide prevalence of C. neoformans serotype A, MATαand genotype VNI among the studied isolates. Conclusions: These data are similar to those obtained in other countries and the first identified by molecular characterization in Guayaquil, Ecuador. Therefore, they constitute an important contribution to the knowledge on cryptococcosis in this country.

Molecular diagnosis of cryptococcal meningitis in cerebrospinal fluid: comparison of primer sets for Cryptococcus neoformans and Cryptococcus gattii species complex

Aim: This study evaluated the use of polymerase chain reaction for cryptococcal meningitis diagnosis in clinical samples. Materials and methods: The sensitivity and specificity of the methodology were evaluated using eight Cryptococcus neoformans/C. gattii species complex reference strains and 165 cere- brospinal fluid samples from patients with neurological diseases divided into two groups: 96 patients with cryptococcal meningitis and AIDS; and 69 patients with other neurological opportunistic diseases (CRL/AIDS). Two primer sets were tested (CN4-CN5 and the multiplex CNa70S-CNa70A/CNb49S-CNb-49A that amplify a specific product for C. neoformans and another for C. gattii). Results: CN4-CN5 primer set was positive in all Cryptococcus standard strains and in 94.8% in DNA samples from cryptococcal meningitis and AIDS group. With the multiplex, no 448-bp product of C. gattii was observed in the clinical samples of either group. The 695 bp products of C. neoformans were observed only in 64.6% of the cryptococcal meningitis and AIDS group. This primer set was negative for two standard strains. The specificity based on the negative samples from the CTL/AIDS group was 98.5% in both primer sets. Conclusions: These data suggest that the CN4/CN5 primer set was highly sensitive for the identification of C. neoformans/C. gattii species complex in cerebrospinal fluid samples from patients with clinical suspicion of cryptococcal meningitis. .

Polimorfismos en los genes de dihidrofolato-reductasa ( dhfr ) y dihidropteroato-sintasa ( dhps ) y modelado estructural del gen dhps en aislamientos colombianos de Toxoplasma gondii / Gene polymorphisms in the dihydrofolate reductase ( dhfr ) and dihydropteroate synthase ( dhps ) genes and structural modelling of the dhps gene in Colombian isolates of Toxoplasma gondii

Introducción. No existen reportes sobre las variaciones en la secuencia de los genes blanco de los medicamentos anti- Toxoplasma en aislamientos provenientes de Suramérica. Objetivo. Clonar y secuenciar los genes de la dihidrofolato-reductasa ( dhfr ) y la dihidropteroato-sintetasa ( dhps ) de la cepa de referencia RH y de dos aislamientos colombianos de Toxoplasma gondii. Materiales y métodos. Se obtuvieron dos aislamientos de T. gondii en líquido céfalorraquídeo de pacientes colombianos positivos para HIV con toxoplasmosis cerebral. Se extrajo el ADN de los genes dhfr y dhps y se amplificaron mediante reacción en cadena de la polimerasa (PCR). Los productos fueron clonados en el vector pGEM-T y secuenciados. Resultados. Se encontró un cambio de adenina por guanina (A « G) en la posición 235 del exón 2 del gen dhps , dos cambios de guanina por citocina (G « C) en las posiciones 259 y 260 y un cambio de timina por guanina (T « G) en la posición 371 del exón 4 del gen dhps. Por análisis bioinformático, en este último exón se identificó un polimorfismo no sinónimo en la región codificante, que podría llevar al cambio de una Glu (CAA o CAG) por una His (codificada por los codones AAU o AAC). Se calculó el modelo estructural de la enzima dihidropteroato-sintetasa (DHPS) de T. gondii y se identificaron las modificaciones en la estructura secundaria ocasionadas por las mutaciones. Conclusiones. La metodología estandarizada puede servir como base para la búsqueda de polimorfismos en muestras de pacientes con diferentes manifestaciones clínicas de toxoplasmosis y para establecer su posible relación con los cambios en la sensibilidad a los antifolatos y la reacción al tratamiento.

Introduction: There are no reports describing polymorphisms in target genes of anti- Toxoplasma drugs in South American isolates. Objective: This study sought to perform cloning and sequencing of the dihydrofolate reductase ( dhfr ) and dihydropteroate-synthase ( dhps ) genes of the reference Rh strain and two Colombian isolates of Toxoplasma gondii . Materials and methods: Two isolates were obtained from the cerebrospinal fluid of HIV-infected patients with cerebral toxoplasmosis. A DNA extraction technique and PCR assay for the dhfr and dhps genes were standardized, and the products of amplification were cloned into Escherichia coli and sequenced. Results: One polymorphism (A « G) was found at position 235 of exon 2 in the dhps gene. In addition, two polymorphisms (G « C) at positions 259 and 260 and one polymorphism (T « G) at position 371 within exon 4 of the dhps gene were detected. In this last exon, a bioinformatic analysis revealed a non-synonymous polymorphism in the coding region that could lead to the substitution of Glu (CAA or CAG) for His (encoded by codons AAU or AAC). A structural model of the T. gondii DHPS protein was calculated, and the results revealed modifications in secondary structure due to mutations. Conclusions: The methods described in this study can be used as a tool to search for polymorphisms in samples from patients with different clinical manifestations of toxoplasmosis and to examine their relationship with the therapeutic response.

Features to validate cerebral toxoplasmosis

Introduction Neurotoxoplasmosis (NT) sometimes manifests unusual characteristics. Methods We analyzed 85 patients with NT and AIDS according to clinical, cerebrospinal fluid, cranial magnetic resonance, and polymerase chain reaction (PCR) characteristics. Results In 8.5%, focal neurological deficits were absent and 16.4% had single cerebral lesions. Increased sensitivity of PCR for Toxoplasma gondii DNA in the central nervous system was associated with pleocytosis and presence of >4 encephalic lesions. Conclusions Patients with NT may present without focal neurological deficit and NT may occur with presence of a single cerebral lesion. Greater numbers of lesions and greater cellularity in cerebrospinal fluid improve the sensitivity of PCR to T gondii. .

Analysis of correlation between cerebrospinal fluid and plasma HIV-1 RNA levels in patients with neurological opportunistic diseases / Análise da correlação entre os níveis de RNA do HIV-1 no líquido cefalorraquidiano e plasma em pacientes com doença neurológica oportunista

The question of whether HIV-1 RNA in cerebrospinal fluid (CSF) is derived from viral replication in the central nervous system or simply reflects the transit of infected lymphocytes from the blood compartment has long been a matter of debate. Some studies found no correlation between CSF and plasma viral load, whereas others did. The lack of a correlation between the two compartments suggests that the presence of HIV-1 RNA is not simply due to the passive passage of the virus from blood to CSF but rather due to intrathecal replication. To evaluate the correlation between plasma and CSF HIV-1 RNA levels and to identify situations in which there is no correlation between the two compartments, seventy patients were prospectively studied. The association between CSF and plasma viral load was evaluated in the total population and in subgroups of patients with similar characteristics. A correlation between the CSF and plasma compartments was observed for patients undergoing highly active antiretroviral therapy (HAART), those with a CD4 T lymphocyte count lower than 200 cells/mm³, and those with increased CSF protein content. On the other hand, no correlation was observed for patients without adequate virological control, who had a CD4 count higher than 200 cells/mm³ and who did not use HAART. The correlation between the two compartments observed in some patients suggests that CSF HIV-1 RNA levels may reflect plasma levels in these subjects. In contrast, the lack of a correlation between the two compartments in patients who were not on HAART and who had normal CSF proteins and a poor virological control possibly indicates compartmentalization of the virus in CSF and, consequently, plasma-independent intrathecal viral replication.

Tem sido objeto de debate a questão se o RNA do HIV-1 no líquido cefalorraquidiano (LCR) é derivado da replicação viral no sistema nervoso central ou simplesmente reflete o tráfego de linfócitos infectados do compartimento sanguíneo. Alguns estudos não mostraram correlação entre a carga viral do plasma e LCR, mas outros sim. A falta de correlação entre os dois compartimentos sugere que a presença de RNA do HIV-1 não é simplesmente devido à passagem do vírus do plasma para o LCR, mas sim a uma replicação intratecal. Para avaliar a correlação entre os níveis de RNA do HIV-1 no plasma e no LCR e tentar identificar situações, na qual, não existe a correlação entre os dois compartimentos avaliaram-se setenta pacientes prospectivamente. A associação entre a carga viral do LCR e plasma foi avaliada na população total e em subgrupos de pacientes com características similares. A correlação entre os dois compartimentos foi observada em pacientes que estavam em uso da terapia antiretroviral (HAART), naqueles que tinham contagem de linfócitos CD4 menor que 200 céls/mm³ e naqueles com aumento da concentração de proteínas no LCR. Por outro lado, não houve correlação para os pacientes que não tinham um controle virológico adequado, os que tinham contagem de CD4 maior que 200 céls/mm³ e aqueles que não estavam usando HAART. A correlação entre os dois compartimentos observada em alguns pacientes sugere que os níveis de RNA do HIV-1 no LCR podem refletir os níveis plasmáticos nestes pacientes. E a falta de correlação ente os dois compartimentos em pacientes que não usavam HAART, nos que tinham uma concentração de proteínas no LCR normal, e nos que não apresentavam bom controle virológico, indica provavelmente a compartimentalização do vírus no LCR e consequentemente replicação viral intratecal independente da do plasma.

Human herpesvirus 6: report of emerging pathogen in five patients with HIV/AIDS and review of the literature / Herpes virus humano 6: relato de patógenos emergentes em cinco pacientes com HIV/AIDS e revisão da literatura

The reactivation of human herpesvirus 6 (HHV-6) in patients with AIDS can result in an acute and severe diffuse meningoencephalitis. We describe the epidemiological, clinical and outcome findings of five patients with diagnosis of HIV/AIDS and central nervous system involvement (CNS) due to HHV-6. Fever was present in all the patients. Meningeal compromise, seizures and encephalitis were present in some of the patients. Polymerase chain reaction (PCR) of cerebrospinal fluid (CSF) specimens was positive for HHV-6 in all the patients. HHV-6 should be included among opportunistic and emerging pathogens that involve the CNS in patients with AIDS.

A reativação do herpesvírus humano 6 (HHV-6), em um hospedeiro com AIDS, pode resultar em meningoencefalite aguda difusa. Nós descrevemos a epidemiologia, a clínica e resultados encontrados em cinco pacientes com diagnóstico de HIV/AIDS e comprometimento do sistema nervoso central (SNC) devido ao HHV-6. Todos os pacientes apresentaram febre. Sinais e sintomas de comprometimento meníngeo, convulsões e encefalite podem ser encontrados. A reação em cadeia da polimerase (PCR) de amostras do líquor foi positiva para HHV-6 em todos os pacientes. O HHV-6 deve ser incluído entre os patógenos emergentes oportunistas que comprometem o SNC de pacientes com AIDS.

Análise molecular de patógenos pela reação em cadeia da polimerase no líquido cefalorraquiano de pacientes infectados com HIV / Molecular analysis of pathogens in cerebrospinal fluid by the polymerase chain reaction in HIV-infected patients

Introdução: A reação em cadeia da polimerase (PCR) foi teste de grande impacto no diagnóstico das meningites e encefalites linfocíticas durante a última década. Esse método foi extensivamente usado no diagnóstico das infecções do sistema nervoso central (SNC), devido a sua habilidade em detectar amostras mínimas de DNA-alvo no líquido cefalorraquiano. Objetivo: O objetivo deste estudo foi identificar a prevalência dos patógenos oportunistas responsáveis por causar problemas neurológicos em pacientes infectados com o vírus da imunodeficiência humana (HIV) e avaliar sua associação com os achados clínicos, laboratoriais e da tomografia computadorizada cerebral (TCC). Pacientes e métodos: Um estudo transversal foi realizado em 203 amostras de líquido cefalorraquiano (LCR) de pacientes do sul do Brasil infectados com HIV e com aparente encefalite e meningite linfocíticas. As amostras foram analisadas para os seguintes agentes pelo método da reação em cadeia da polimerase "nested" ou dupla (N-PCR): citomegalovírus, vírus do Epstein-Barr, vírus do herpes simplex tipos 1 e 2, vírus da varicella zoster, vírus do herpes humano tipo 6, vírus JC, Toxoplasma gondii e micobactérias. Resultado: Pelo menos um patógeno foi encontrado em 77 (38%) dos indivíduos. O Epstein-Barr foi o mais prevalente, com 40 casos (19,7%), seguido pelo citomegalovívus, com 12 casos (15%) e pelo vírus JC, em 9 casos (4,4%). Um N-PCR positivo mostrou associação com aumento de proteínas e de celularidade (P=0,001), meningismo (P=0,017) e tomografia computadorizada anormal (P=0,006). Conclusão: O painel de PCR empregado foi efetivo na identificação de infecções neurológicas severas em pacientes HIV positivos (AU)

Introduction: Polymerase chain reaction (PCR) has had great impact on the diagnosis of lymphocytic meningitis and encephalitis over the last decade. It has been extensively used in the diagnosis of central nervous system (CNS) infections for its ability to detect small amounts of target DNA in the cerebrospinal fluid (CSF). Objective: The aim of this study was to identify the prevalence of opportunistic pathogens responsible for neurological disorders in patients infected with human immunodeficiency virus (HIV) and to evaluate its association with clinical, laboratory and cerebral computed tomography (CCT) findings. Patients and methods: A cross-sectional study was performed on 203 cerebrospinal fluids (CSF) from HIV-infected patients from Southern Brazil, with apparent lymphocytic meningitis and encephalitis. CSF samples were analyzed with probes for cytomegalovirus, Epstein-Barr virus, herpes simplex virus types 1 and 2, varicella zoster virus, human herpes virus type 6, JC virus, Toxoplasma gondii and mycobacterium in nested polymerase chain reaction (N-PCR). Results: At least one pathogen was found in 77 (38.0%) individuals. Epstein-Barr virus was the most prevalent with 40 cases (19.7%), followed by cytomegalovirus with 12 cases (5.9%) and JC virus with 9 cases (4.4%). Positive NPCR showed association with high spinal fluid protein and cell count (P=0.001), meningism (P=0.017) and abnormal CCT (P=0.006). Conclusion: The PCR panel used was effective in screening several neurological infections in HIV positive patients (AU)

Neurotoxoplasmosis diagnosis for HIV-1 patients by real-time PCR of cerebrospinal fluid

Encephalitis caused by Toxoplasma gondii is the most common cause of central nervous system damage in patients with acquired immunodeficiency syndrome (AIDS). Toxoplasma may infect any of the brain cells, thus leading to non-specific neurotoxoplasmosis clinical manifestations including focused or non-focused signs and symptoms of central nervous system malfunction. Clinical development ranges from insidious display during weeks to experiencing acute general confusion or ultimately fatal onset. Cerebral toxoplasmosis occurs in advanced stages of immunodeficiency, and the absence of anti-toxoplasmosis antibodies by the immunofluorescence method does not allow us to rule out its diagnosis. As specific therapy begins, diagnosis confirmation is sought through clinical and radiological response. There are few accurate diagnosis methods to confirm such cases. We present a method for T. gondii DNA detection by real time PCR-Multiplex. Fifty-one patients were evaluated; 16 patients had AIDS and a presumptive diagnosis for toxoplasmosis, 23 patients were HIV-positive with further morbidities except neurotoxoplasmosis, and 12 subjects were HIV-negative control patients. Real time PCR-Multiplex was applied to these patients' cephalorachidian liquid with a specific T. gondii genome sequence from the 529bp fragment. This test is usually carried out within four hours. Test sensitivity, specificity, positive predictive value, and negative predictive value were calculated according to applicable tables. Toxoplasma gondii assay by real time Multiplex of cephalorachidian fluid was positive for 11 out of 16 patients with AIDS and a presumptive diagnosis for cerebral toxoplasmosis, while none of the 35 control patients displayed such a result. Therefore, this method allowed us to achieve 68.8 percent sensitivity, 100 percent specificity, 100 percent positive predictive value, and 87.8 percent negative predictive value. Real time PCR on CSF allowed high specificity...

Síndrome de restauración inmune asociado a tratamiento antirretroviral y criptococosis meníngea: Caso clínico / Inflammatory reconstitution immune syndrome associated to antiretroviral therapy and meningeal cryptococcosis

The objective of high activity antiretroviral therapy (HAART) in patients with AIDS, is to obtain immune restoration. This means a reduction of the viral load and restitution of the CD4 cell count. A decreased rate of HIV replication improves both the number and function of CD4 cells. Nevertheless, this treatment sometimes results in the reappearance of previous symptoms from treated conditions due to opportunistic infections (ie: tuberculosis, criptococcosis, hepatitis, Pneumocystis jirovesi, toxoplasmosis, etc) or non infectious condition such as sarcoidosis, Graves disease or Kaposi sarcoma. This is known as Inflammatory Reconstitution Immune Syndrome (IRIS). We report a 37 year-old woman in stage C3-AIDS with a previous criptococcal meningitis. She was treated, achieving a marked improvement with treatment and subsequent suppressive therapy with fluconazole 200 mg/day. IRIS appeared after 8 months of ongoing antiretroviral therapy with immune restoration with the development of aseptic meningitis and intracranial hypertension. The opportunistic agent could not be identified by cultures. Additional laboratory tests excluded toxoplasmosis, tuberculosis, bacterial cerebral abscesses, syphilitic cerebral gummas, and lymphoma. Brain CT and magnetic resonance studies were compatible with brain vasculitis and leptomeningitis. The patient condition improved with general measures, such as a repeated lumbar punctures and non steroidal anti-inflammatory drugs. We conclude that this patient had an IRIS due to a Cryptococcus neoformans antigen.

HIV-1 RNA levels in cerebrospinal fluid and plasma and their correlation with opportunistic neurological diseases in a Brazilian AIDS reference hospital

INTRODUÇÃO: Os níveis de RNA do HIV-1 no plasma refletem a replicação viral sistêmica e a replicação no sistema nervoso central pode ocorrer independentemente da infecção sistêmica, mas a utilidade da medida destes níveis no líquido cefalorraqueano (LCR) permanece indefinida. OBJETIVO: Comparar os níveis de RNA do HIV-1 no LCR e plasma de pacientes sem doenças neurológicas e com diferentes doenças neurológicas, bem como correlacionar estes níveis com a sua evolução e o uso de antiretrovirais. MÉTODO: Foram avaliados 97 pacientes com suspeita de doença neurológica que realizaram punção lombar e que foram divididos em dois grupos: sem doenças neurológicas (23) e com doenças neurológicas (74). Metodologia NASBA foi usada para quantificação do RNA do HIV-1. RESULTADOS: A mediana da carga viral do LCR foi maior em pacientes com neurotoxoplasmose, neurocriptococose, demência pelo HIV e doença neurológica sem etiologia definida quando comparada aos pacientes sem doenças neurológicas. Não houve diferença da carga viral do plasma entre os pacientes com e sem doença neurológica. A mediana da carga viral do plasma e LCR foi maior nos pacientes que faleceram em relação aos tratados com sucesso. A carga viral do LCR e plasma foi menor nos pacientes com doenças oportunísticas que usavam HAART em relação aos que não a usavam. CONCLUSÃO: A carga viral no LRC foi maior nos pacientes com qualquer doença neurológica em relação aos sem doenças neurológicas, mas isto não ocorreu no plasma, sugerindo que doença neurológica influencia mais o compartimento do LCR que o do plasma, mas não foi possível diferenciar as doenças neurológicas pelos níveis de RNA do HIV-1 do LCR.

Leucoencefalopatia multifocal progressiva confirmada por PCR para vírus JC no líquor: relato de caso / Progressive multifocal leukoencephalopathy confirmed by PCR for JC virus in cerebrospinal fluid: case report

Relatamos um caso de leucoencefalopatia multifocal progressiva, doença infecciosa desmielinizante do sistema nervoso central, seguido de revisão da literatura. Comenta-se a importância diagnóstica dos métodos de imagem, bem como da análise do líquor e da técnica de reação em cadeia da polimerase (PCR). Até o presente momento, não há terapia efetiva para a condição, com sobrevida média de 1-6 meses nos pacientes não tratados; evolução favorável pode ocorrer no subgrupo de pacientes que obtém melhora da imunidade com o uso de terapia anti-retroviral.

Reactivation of Chagas' disease leading to the diagnosis of acquired immunodeficiency syndrome

Reactivation of chronic Chagas' disease is a rare condition and occurs only in immunosuppressed patients. We report a case of a patient with a rapid and fatal reactivation of Chagas' disease, manifested by meningoencephalitis, which lead to a diagnosis of acquired immunodeficiency syndrome (AIDS). We believe there is sufficient evidence to include the reactivation of Chagas' disease among the diagnostic criteria of AIDS in Human Immunodeficiency Virus (HIV) infection.

Cryptococcus neoformans causing meningitis in AIDS patients

Cryptococcus neoformans causes meningitis in AIDS patients. In the Säo José Hospital, reference center for patients with AIDS in Fortaleza - Ceará State - Brazil, 54 samples of the cerebrospinal fluid were analyzed from January 1st through December 31st 2000. Direct examination with India ink and culture in Sabouraud's agar at 37°C were done. Of the specimens studied 5(9.25 percent) were positive

Criptococosis meníngea asociada al SIDA en el Hospital Diego Paroissien en el período 1996/1999 / AIDS-associated meningeal cryptococcosis in the Hospital Diego Paroissien from 1996-1999

A total of 148 patients with a diagnosis of HIV infection were studied in order to evaluate the incidence of meningeal cryptococcosis, including epidemic, immunologic and diagnostic characteristics. The diagnosis of cryptococcosis was carried out by direct examination with India ink and culture in Sabouraud agar of CSF in 28 patients (93.3) and by blood cultures (lysis-centrifugation) in 2 patients (6.6). All the isolated strains were identified as Cryptococcus neoformans. The incidence was 20.3 (30 patients). The preponderant risk behavior was endovenous drug addiction, and it was observed in 18 patients (60). The symptomatology that prevailed was headache (87). The median age was 28 years. At diagnosis, the immunologic impairment was severe (CD4+ lymphocyte count < 200) in 90 of patients. We found that 86.7 of patients had not completed their primary studies and only 13.3 had completed secondary studies. Although the acute mortality was high (36.7), it was observed that all the patients who survived (24) had been treated with anti-retroviral drugs.

Trypanosoma cruzi meningoencephalitis in AIDS mimicking cerebral metastases: case report

A case of Chagas' meningoencephalitis in a 47 year-old patient with AIDS is presented. The diagnosis was established by examination of the cerebrospinal fluid which showed the presence of Trypanosoma cruzi. CT-scan revealed multiple cerebral lesions which only became evident by contrast administration. A second CT after 13 days showed a severe evolution with displacement of the midline structures leading to the patient's death. This case, as well as other case reports published, has shown the fulminant evolution of Chagas'meningoencephalitis in AIDS patients and the importance of cerebrospinal fluid examination for the diagnosis.

Criptococosis del sistema nerviosos central. Estudio de 32 casos 1975-1991

Este es el segundo estudio sobre criptococosis del sistema nervioso central (SNC) realizado en el Centro Hospitalario San Juan de Dios de Bogotá; corresponde al período 1975 -1991 y comprende 32 casos. LLama la atención en este período el aumento de la referencia de esta enfermedad en esta institución en los últimos tres años y su asociación con el SIDA (cinco casos). Los principales síntomas y signos observados fueron : cefale (26/32), alteraciones de conciencia (23/32), náuseas y vómito (19/32), signos meníngeos (18/32), fiebre (14/32) y papiledema (15/32). E diagnóstico se confirmó por uno a varios de los siguientes estudios : examen directo del LCR (tinta china) positivo en 75 por ciento, cultivo positivo del LCR en 96 por ciento, aglutinación de látex positiva en LCR en 90 por ciento, aglutinación de látex positiva en suero en 72 por ciento y hallazgos histopatológicos demostrativos de la criptococosis a nivel del SNC en nueve casos de autopsia. Se analizan la alta mortalidad (21/32 casos) y las dificultades del tratamiento.