Prevalence and genotype distribution of Pneumocystis jirovecii in Cuban infants and toddlers with whooping cough.

This study describes the prevalence and genotype distribution of Pneumocystis jirovecii obtained from nasopharyngeal (NP) swabs from immunocompetent Cuban infants and toddlers with whooping cough (WC). A total of 163 NP swabs from 163 young Cuban children with WC who were admitted to the respiratory care units at two pediatric centers were studied. The prevalence of the organism was determined by a quantitative PCR (qPCR) assay targeting the P. jirovecii mitochondrial large subunit (mtLSU) rRNA gene. Genotypes were identified by direct sequencing of mtLSU ribosomal DNA (rDNA) and restriction fragment length polymorphism (RFLP) analysis of the dihydropteroate synthase (DHPS) gene amplicons. qPCR detected P. jirovecii DNA in 48/163 (29.4%) samples. mtLSU rDNA sequence analysis revealed the presence of three different genotypes in the population. Genotype 2 was most common (48%), followed in prevalence by genotypes 1 (23%) and 3 (19%); mixed-genotype infections were seen in 10% of the cases. RFLP analysis of DHPS PCR products revealed four genotypes, 18% of which were associated with resistance to sulfa drugs. Only contact with coughers (prevalence ratio [PR], 3.51 [95% confidence interval {CI}, 1.79 to 6.87]; P = 0.000) and exposure to tobacco smoke (PR, 1.82 [95% CI, 1.14 to 2.92]; P = 0.009) were statistically associated with being colonized by P. jirovecii. The prevalence of P. jirovecii in infants and toddlers with WC and the genotyping results provide evidence that this population represents a potential reservoir and transmission source of P. jirovecii.

Cryptococcus and cryptococcosis in Cuba. A minireview.

Cryptococcosis has emerged as an important public health problem in Africa, Asia and the Americas due to the increasing numbers of persons at risk of this infection and the adaptation of its aetiological agents to new environments. The proper management requires early recognition of Cryptococcus neoformans/C. gattii species complex infection, familiarity with the use and limitations of diagnostic tests and knowledge of the available treatment options. This review will address these issues with the goal of providing sufficient information to suspect, diagnose and treat patients with cryptococcosis based on Cuban data and review of the literature.

Microsatellite typing and susceptibilities of serial Cryptococcus neoformans isolates from Cuban patients with recurrent cryptococcal meningitis.

BACKGROUND: Cryptococcus neoformans is commonly associated with meningoencephalitis in immunocompromised patients and occasionally in apparently healthy individuals. Recurrence of infection after initial treatment is not uncommon. We studied C. neoformans isolates from 7 Cuban patients with recurrent cryptococcal meningitis. Antifungal susceptibility and genotyping with microsatellite molecular typing were carried out. METHODS: Isolates (n = 19) were recovered from cerebrospinal fluid, blood, urine and semen. Antifungal susceptibilities for amphotericin B, fluconazole, flucytosine, itraconazole, voriconazole, posaconazole and isavuconazole were tested by CLSI M27A3 broth microdilution method. Genotyping was done using a panel of 9 microsatellite (STR) markers: (CT)n, (TG)n, (TA)n, (CTA)n, (TCT)n, (CCA)n, (TTAT)n, (ATCC)n and (TATT)n. RESULTS: The average number of isolates/patient was 2.71. The mean time interval between the collection of any two isolates was 52.5 days. All strains were identified as C. neoformans var. grubii (serotype Aα). Although none of the strains were resistant to the studied drugs, in serial isolates from two patients, MICs values of triazoles increased 4-5 log2 dilutions over time. STR patterns showed 14 distinctive profiles. In three patients the recurrent infection was associated with genotypically identical isolates. The four other patients had relapse isolates which were genotypically different from the initial infecting strain. CONCLUSION: Recurrences of cryptococcal meningitis in our series of patients was not associated with development of drug resistance of the original strain but by an initial infection with different strains or a reinfection with a new strain.

Non-traumatic keratitis due to Colletotrichum truncatum.

INTRODUCTION: The fungal genus Colletotrichum is an uncommon cause of human infections. It has been implicated in cutaneous phaeohyphomycosis, artritis and keratitis secondary to traumatic implantation. CASE PRESENTATION: We report two cases of keratitis due Colletotrichum truncatum in middle-aged, immunocompetent persons without history of trauma. The aetiological agents were identified based on DNA sequencing. Azoles and echinocandins showed high minimal inhibitory concentrations while amphotericin B was ≤ 0.25 mg l-1. Both patients failed topical antifungal treatment and needed penetrating keratoplasty with a favourable outcome. CONCLUSION: C. truncatum caused keratomycosis which did not respond to topical antifungal agents. To the best of our knowledge these are the first reported cases of keratitis due to this fungus in Cuba and Latin-America and highlights the expanding spectrum of fungal agents causing eye infections.

Genetic diversity of Pneumocystis jirovecii in colonized Cuban infants and toddlers.

Pneumocystis jirovecii is a leading cause of opportunistic infections among immunocompromised patients. The aim of this study was to determine the genetic diversity of P. jirovecii from colonized Cuban infants and toddlers by analysis of four genetic loci: mitochondrial large subunit (mtLSU) rRNA, cytochrome b (CYB), superoxide dismutase (SOD) and ß-tubulin (ß-tub). We determined the multilocus profiles based on concatenated genotype data (multilocus genotype; MLG) and nucleotide sequences (multilocus sequence analysis; MLSA) respectively, calculated the discriminatory power of each analysis, and investigated possible associations with demographic and clinical data. Sixteen of 51 PCR-positive nasopharyngeal swab specimens (years 2010-2013) with high P. jirovecii load were selected for downstream analysis. In mixed allelic profiles all genotypes/nucleotide sequence patterns were considered separately. All samples could be genotyped based on mtLSU, CYB and ß-tub locus. However, the SOD locus could be successfully amplified in only 7/16 (44%) specimens. Eight different P. jirovecii MLGs were identified among the 16 cases and eight samples presented identical MLG (MLG 1). Seventeen MLSA profiles were distinguished. No statistical association between genotypes or MLGs and demographic or clinical data could be identified. For MLSA the higher discriminatory power (S=0.976) was observed. The combination of mtLSU, CYB and ß-tub loci proved to be useful for molecular epidemiology studies of P. jirovecii. A total of 17 different MLSA profiles observed in 16 specimens indicated high genetic variability of P. jirovecii circulating in colonized Cuban infants and toddlers.

Fatal Cryptococcus gattii genotype AFLP5 infection in an immunocompetent Cuban patient.

We describe the first clinical case of cryptococcosis due C. gattii in a Cuban immunocompetent patient who had a traveling history two years before to Central America. Molecular characterization of the isolate showed it to be genotype AFLP5 of which MLST sequences clustered with clinical and environmental strains from Colombia. The patient died one year after the diagnosis despite a prolonged treatment with (liposomal) amphotericin B, fluconazole, voriconazole and gamma interferon.

Neurocriptococosis en el contexto de la infección con el VIH en Guayaquil, Ecuador / Neurocryptococcosis in the context of HIV infection in Guayaquil, Ecuador

Introducción: la neurocriptococosis resulta de la inhalación de levaduras del complejo de especies Cryptococcus neoformans y afecta principalmente a pacientes inmunocomprometidos, provocando altas tasas de mortalidad. Objetivo: describir la infección por Cryptococcus spp. en pacientes con VIH/sida de Guayaquil, Ecuador. Métodos: estudio descriptivo, transversal y prospectivo, entre diciembre/2013-enero/2015. Se recopilaron 82 muestras de líquido cefalorraquídeo así como los datos demográficos, clínicos y de laboratorio de igual cantidad de pacientes seropositivos al VIH ingresados en el Hospital de Infectología Dr. José Daniel Rodríguez Maridueña. La infección criptococósica se confirmó mediante examen microscópico directo del líquido cefalorraquídeo con tinta china, cultivo en agar Sabouraud y pruebas bioquímicas convencionales. El estudio cumplió con los requerimientos éticos establecidos. Resultados: el 89,02 por ciento de los pacientes incluidos en el estudio fueron de género masculino y el 45,12 por ciento del grupo etario de 20-30 años. El 33 por ciento de los pacientes presentaron la infección por C. neoformans, y sus características clínicas más frecuentes fueron: impresión diagnóstica de neuroinfección (41 por ciento), cefalea (78 por ciento; 21/27), vómitos (85 por ciento; 23/27) y pérdida de peso (89 por ciento; 24/27); niveles de CD4 < 200/uL (26 por ciento; 7/27), leucocitos 5 000-10 000 cél/mm3 (63 por ciento; 17/27), hemoglobina 11-15 g/dL (44 por ciento; 12/27) y hematócrito < 35 por ciento (78 por ciento; 21/27). Se demostró además, la existencia de una asociación entre la infección y la presencia de vómitos, pérdida de peso y adenopatías (razón de prevalencias > 1). Conclusiones: La infección criptococósica es una importante micosis oportunista en pacientes VIH-SIDA, que puede ser asociada a determinadas características, lo que permite definir mecanismos de control y prevención(AU)

Introduction: neurocryptococcosis results from inhalation of yeasts from the Cryptococcus neoformans species complex. The disease mainly affects immunocompromised patients, causing high mortality rates. Objective: describe infection due to Cryptococcus spp. in patients with HIV/AIDS from Guayaquil, Ecuador. Methods: a descriptive cross-sectional prospective study was conducted from December 2013 to January 2015. Eighty-two cerebrospinal fluid samples were collected, as well as the demographic, clinical and laboratory data of an equal number of HIV seropositive inpatients from Dr. José Daniel Rodríguez Maridueña infectious diseases hospital. Cryptococcal infection was confirmed by India ink direct microscopic examination of cerebrospinal fluid, Sabouraud agar culture and conventional biochemical tests. The study met the ethical requirements established. Results: 89.02 percent of the patients included in the study were male and 45.12 percent were in the 20-30 years age group. 33 percent had infection with C. neoformans, and their most common clinical features were diagnostic impression of neuroinfection (41 percent), headache (78 percent; 21/27), vomiting (85 percent; 23/27), weight loss (89 percent; 24/27); CD4 counts < 200/uL (26 percent; 7/27), leucocytes 5 000-10 000 cells/mm3 (63 percent; 17/27), hemoglobin 11-15 g/dL (44 percent; 12/27) and hematocrit < 35 percent (78 percent; 21/27). An association was also found between infection and the presence of vomiting, weight loss and adenopathies (prevalence ratio >1). Conclusions: cryptococcal infection is an important opportunistic mycosis in HIV/AIDS patients. It may be associated with certain features, which makes it possible to define control and prevention mechanisms(AU)

[Histoplasmosis updating]. / Una actualización acerca de histoplasmosis.

Histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, has been reported all over the world and is considered endemic in the American continent, including Cuba. This fungus grows on the soils contaminated with bird and bat excreta, where it produces a great number of microconidia that could cause the infection when they are inhaled. The clinical spectrum varies from asymptomatic infections to serious disseminated diseases involving one or many organ systems and affects mainly AIDS patients, patients with hematological neoplasias, transplant recipients or other immunosuppressed patients. The main risk groups include those individuals whose working activities make them be exposed to aerosols contaminated with H. capsulatum. Lab diagnosis is based on the microscopic observation, isolation and identification of the fungus in fluid or tissue samples of patients, and on specific antigen and antibodies detection. The molecular methods based on polymerase chain reaction have not been sufficiently defined, and they could be an important advance in the early diagnosis of this mycosis. Itraconazole is recommended for treatment of moderate, localized and chronic infection whereas amphotericin B is the drug of choice for disseminated and serious manifestations, particularly in its lipidic formulations. At present, histoplasmosis is considered one of the most important systemic mycoses in the Americas, and it is widely spread over all regions of Cuba.

Susceptibilidad antimicrobiana en aislamientos cubanos de Vibrio cholerae O1 procedentes de muestras clínicas / Antimicrobial susceptibility in Cuban isolates of Vibrio cholerae O1 obtained from clinical samples

Introducción: la re-emergencia de cólera en Haití estableció un nuevo reservorio para el incremento de la séptima pandemia. Esto provocó su diseminación a República Dominicana y a otros países de la región del Caribe, como Cuba y México. Objetivo: estudiar la susceptibilidad antimicrobiana de aislamientos de Vibrio cholerae O1, serotipo Ogawa, biotipo El Tor aisladas de pacientes durante el evento epidemiológico de cólera ocurrido en Cuba entre junio de 2012 y agosto de 2013. Métodos: se realizó el estudio de la susceptibilidad antimicrobiana in vitro en 144 aislamientos de V. cholerae, mediante el método de Bauer-Kirby frente a nueve antimicrobianos: ampicilina, sulfonamida, trimetoprim/sulfametoxazol, cloranfenicol, tetraciclina, doxiciclina, azitromicina, ciprofloxacina y gentamicina, según las normas del Instituto de Estándares de Laboratorio Clínico de los Estados Unidos de América. Resultados: el total de los aislamientos resultaron resistentes al trimetoprim-sulfametoxazol; el 98,7 por ciento lo fue a la sulfonamida y el 90,3 por ciento a la ampicilina. Se obtuvieron valores de sensibilidad intermedia para ciprofloxacina (30,6 por ciento) y cloranfenicol (27,1 por ciento). Se apreciaron niveles de sensibilidad superior al 92 por ciento a los antimicrobianos de primera línea en el tratamiento de la enfermedad (doxiciclina, tetraciclina y azitromicina), así como también a la gentamicina. No se observaron cepas multirresistentes. Conclusiones: los datos aportados por este trabajo demuestran la efectividad in vitro de los antimicrobianos utilizados en el tratamiento la enfermedad diarreica aguda causada por V. cholerae en Cuba(AU)

Introduction: re-emergence of cholera in Haiti created a new reservoir for the increase of the seventh pandemic. This resulted in its spread to the Dominican Republic and other Caribbean countries, such as Cuba and Mexico. Objectives: study the antimicrobial susceptibility of isolates of Vibrio cholerae O1, Ogawa serotype, El Tor biotype, obtained from patients during the cholera epidemiological event occurring in Cuba from June 2012 to August 2013. Methods: a study was conducted of 144 V. cholerae isolates using the Bauer-Kirby method to determine in vitro susceptibility to nine antimicrobials: ampicillin, sulfonamide, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline, doxycycline, azithromycin, ciprofloxacin and gentamicin, in compliance with standards from the U.S. Clinical and Laboratory Standards Institute. Results: all isolates were resistant to trimethoprim/sulfamethoxazole; 98.7 percent to sulfonamide and 90.3 percent to ampicillin. Intermediate sensitivity values were obtained for ciprofloxacin (30.6 percent) and chloramphenicol (27.1 percent). Sensitivity levels above 92 percent were found for first-line antimicrobials (doxycycline, tetracycline and azithromycin), as well as gentamicin. Multi-drug resistant strains were not found. Conclusions: results reveal the effectiveness in vitro of the antimicrobials used in Cuba to treat acute diarrheal disease caused by V. cholerae(AU)

[In vitro susceptibility of Candida strains to fluconazole and amphotericin B]. / Sensibilidad in vitro de cepas de Candida frente a fluconazol y anfotericina B.

In vitro antifungal susceptibility testing is really necessary at present in medical mycology laboratories. Minimal inhibitory concentration of 210 Candida yeast strains isolated from HIV/AIDS patients with oral lesions was determined to find out susceptibility to fluconazole and amphotericin B. A CLSI's M27A2 protocol-based dilution micromethod was used. C. albicans was predominant (62.4%)followed by C. glabrata, C. parapsilosis, and C. tropicalis. Regarding amphotericin B, the mode value and MIC50 were 0.125 microg/mL, which indicated the effectiveness of this drug in vitro conditions. Only C. krusei strain showed a minimal inhibitory concentration over 1 microg/mL. 8.1% of strains were resistent to fluconazole whereas 8.1% was dose-depending susceptible. The less susceptible species were C. krusei and C. glabrata. The achieved results laid the foundations for wider studies to be made in the Cuban context and indicated the need of keeping surveillance on the behaviour of clinical yeast isolates to antifungal drugs.

[Recognition of intact cells from Cryptococcus neoformans by the anti-glucuronoxylomannan 4B3 monoclonal antibody]. / Reconocimiento de células intactas de Cryptococcus neoformans por el AcM 4B3 antiglucuronoxilomanano.

The capacity of the 4B3 monoclonal antibody, previously obtained by immunization of BALB/c mice with the capsular polysaccharide of Cryptococcus neoformans was studied to recognize this structure as part of the intact cell of this yeast. With this aim, 4B3 was evaluated by cellular ELISA and indirect immunofluorescence, using as an antigen a cell suspension of the 028 LMIPK C. neoformans strain. Serum from the mouse used in the fusion for obtaining 4B3 monoclonal antibody was used as a positive control, whereas an anti-dengue monoclonal antibody was used as a negative control. Both methods demonstrated that the above mentioned monoclonal antibody is capable of recognizing the native antigen, which will allow its future evaluation for diagnostic and therapeutic purposes.

Una actualización acerca de histoplasmosis / Histoplasmosis updating

La histoplasmosis infección causada por el hongo Histoplasma capsulatum ha sido reportada en todos los continentes y se considera endémica en el continente americano, incluida Cuba. El hongo se desarrolla en el suelo con excretas de aves y murciélagos, donde es capaz de producir abundantes microconidios, que al ser inhalados por el hombre son capaces de causar la infección. El cuadro clínico puede variar, desde infecciones asintomáticas hasta cuadros diseminados graves que involucran a uno o varios órganos y sistemas y que afectan sobre todo a pacientes con sida, neoplasias hematológicas, con trasplantes u otras inmunodeficiencias. Los principales grupos de riesgo incluyen además, aquellos individuos que por razones ocupacionales se expongan los aerosoles contaminados con el hongo. El diagnóstico de laboratorio se basa en la observación de este en fluidos y tejidos orgánicos, en el cultivo de esos materiales y en la detección de anticuerpos y antígenos específicos. Los métodos moleculares, en especial mediante la reacción en cadena de la polimerasa, aunque no han sido suficientemente evaluados, pudieran representar un importante avance en el diagnóstico temprano de esta micosis. Para el tratamiento de las formas agudas moderadas, localizadas y respiratoria crónica se recomienda el itraconazol, mientras que para las formas graves y diseminadas la droga de elección es la anfotericina B, con preferencia en alguna de sus formulaciones lipídicas. La histoplasmosis representa hoy una de las micosis sistémicas más importante en las Américas, con una amplia distribución en todas las regiones de Cuba.

Histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, has been reported all over the world and is considered endemic in the American continent, including Cuba. This fungus grows on the soils contaminated with bird and bat excreta, where it produces a great number of microconidia that could cause the infection when they are inhaled. The clinical spectrum varies from asymptomatic infections to serious disseminated diseases involving one or many organ systems and affects mainly AIDS patients, patients with hematological neoplasias, transplant recipients or other immunosuppressed patients. The main risk groups include those individuals whose working activities make them be exposed to aerosols contaminated with H. capsulatum. Lab diagnosis is based on the microscopic observation, isolation and identification of the fungus in fluid or tissue samples of patients, and on specific antigen and antibodies detection. The molecular methods based on polymerase chain reaction have not been sufficiently defined, and they could be an important advance in the early diagnosis of this mycosis. Itraconazole is recommended for treatment of moderate, localized and chronic infection whereas amphotericin B is the drug of choice for disseminated and serious manifestations, particularly in its lipidic formulations. At present, histoplasmosis is considered one of the most important systemic mycoses in the Americas, and it is widely spread over all regions of Cuba.

[Obtention of specific antisera for the serotyping of Cryptococcus neoformans var. neoformans]. / Obtención de antisueros específicos para la serotipificación de Cryptococcus neoformans var. neoformans.

The obtention of antisera at the Mycology Laboratory of "Pedro Kouri" Institute of Tropical Medicine was proposed to allow the rapid identification of the varieties and serotypes of Cryptococcus neoformans, since it is very important from the clinico-epidemiological point of view to know them. By immunizing rabbits with formalized whole cells of the 4 serotypes of this yeast, it was possible to obtain antisera that were absorbed with cells of the heterologous serotypes. 3 antisera capable of differentiating the neoformans var. (anti AD) and its respective serotypes (anti-A and anti-D) were attained. This paper will contribute to the knowledge of the epidemiology of this important disease in the Cuban setting for being the first time that useful antisera are obtained in Cuba to identify the serotypes corrresponding to the neoformans variety, which is the main causal agent of criptococcosis.

[Usefulness of D-proline in the differentiation of varieties of Cryptococcus neoformans]. / Utilidad de la D-prolina en la diferenciación de las variedades de Cryptococcus neoformans.

A comparative study was conducted between the assimilation of D-proline and the growth on canavanine-glycine-bromothymol blue (CGB) medium used for the classification of the varieties of Cryptococcus neoformans. In the 86 studied strains, 100% of coincidence between both methods allowed to affirm that 95.34% corresponded to the neoformans var. and the rest (4.65%) to the gattii var. The results obtained corroborated that all the autoctonous clinical isolations up to the present correspond to the. neoformans var. and made possible to suggest the use of D-proline for the initial evaluation of strains, as an alternative and simple method that presented under these conditions high coincidence with the reference method (growth in CGB).

Sensibilidad in vitro de cepas de Candida frente a fluconazol y anfotericina B / In vitro susceptibility of Candida strains to fluconazole and amphotericin B

Las pruebas de sensibilidad in vitro a los agentes antifúngicos se han convertido en una necesidad actual de los laboratorios de micología médica. Se determinó la concentración mínima inhibitoria de 210 cepas de levaduras del género Candida aisladas de pacientes VIH/SIDA que presentaban lesiones orales, con el objetivo de conocer la sensibilidad a fluconazol y anfotericina B. Fue utilizado un micrométodo de dilución según el protocolo M27A2 del CLSI. C. albicans fue la especie predominante (62,4 por ciento), seguida, en orden de frecuencia, de C. glabrata, C. parapsilosis, C. krusei y C. tropicalis. Frente a la anfotericina B el valor de la moda y la CMI50 fue de 0,125 µg/mL, lo que indica la efectividad in vitro de este fármaco. Solo una cepa (C. krusei) mostró una concentración mínima inhibitoria superior a 1 µg/mL. De las cepas, 8,1 por ciento resultó resistente al fluconazol y 8,1 por ciento sensible dependiente de la dosis. Las especies que se comportaron menos sensibles fueron C. krusei y C. glabrata. Los resultados obtenidos sentaron las bases para estudios más amplios en el medio cubano y sugirieron la necesidad de continuar la vigilancia del comportamiento de los aislamientos clínicos de levaduras frente a los agentes antifúngicos.

In vitro antifungal susceptibility testing is really necessary at present in medical mycology laboratories. Minimal inhibitory concentration of 210 Candida yeast strains isolated from HIV/AIDS patients with oral lesions was determined to find out susceptibility to fluconazole and amphotericin B. A CLSI´s M27A2 protocol-based dilution micromethod was used. C. albicans was predominant (62.4 percent)followed by C. glabrata, C. parapsilosis, and C. tropicalis. Regarding amphotericin B, the mode value and MIC50 were 0,125 µg/mL, which indicated the effectiveness of this drug in vitro conditions. Only C. krusei strain showed a minimal inhibitory concentration over 1 µg/mL. 8.1 percent of strains were resistent to fluconazole whereas 8.1 percent was dose- depending susceptible. The less susceptible species were C. krusei and C. glabrata. The achieved results laid the foundations for wider studies to be made in the Cuban context and indicated the need of keeping surveillance on the behaviour of clinical yeast isolates to antifungal drugs.

Reconocimiento de células intactas de Cryptococcus neoformans por el AcM 4B3 antiglucuronoxilomanano / Recognition of intact cells from Cryptococcus neoformans by the anti-glucuronoxylomannan 4B3 monoclonal antibody

Se estudió la capacidad del anticuerpo monoclonal 4B3, obtenido mediante inmunización de ratones BALB/c con el polisacárido capsular de Cryptococcus neoformans, para reconocer a dicha estructura como parte de la célula intacta de esta levadura. Con este propósito el anticuerpo 4B3 fue evaluado mediante ELISA celular e inmunofluorescencia indirecta empleando como antígeno una suspensión de células de la cepa 028 LMIPK de Cryptococcus neoformans. Se usó como control positivo suero del ratón empleado en la fusión para la obtención del anticuerpo monoclonal 4B3 y como control negativo un anticuerpo monoclonal anti-dengue. Ambos métodos demostraron que este anticuerpo monoclonal es capaz de reconocer al antígeno nativo, lo que permitirá su posterior evaluación con fines diagnósticos y terapéuticos

The capacity of the 4B3 monoclonal antibody, previously obtained by immunization of BALB/c mice with the capsular polysaccharide of Cryptococcus neoformans was studied to recognize this structure as part of the intact cell of this yeast. With this aim, 4B3 was evaluated by cellular ELISA and indirect immunofluorescence, using as an antigen a cell suspension of the 028 LMIPK C. neoformans strain. Serum from the mouse used in the fusion for obtaining 4B3 monoclonal antibody was used as a positive control, whereas an anti-dengue monoclonal antibody was used as a negative control. Both methods demonstrated that the above mentioned monoclonal antibody is capable of recognizing the native antigen, which will allow its future evaluation for diagnostic and therapeutic purposes.

Utilidad de la D-prolina en la diferenciación de las variedades de Cryptococcus neoformans / Usefulness of D-proline in the differentiation of varieties of Cryptococcus neoformans

Se realizó un estudio comparativo entre la asimilación de la D-prolina y el crecimiento en medio canavanina-glicina-azul de bromotimol (CGB) utilizados para la clasificación de las variedades de Cryptococcus neoformans. En las 86 cepas estudiadas, 100 por ciento de coincidencia entre ambos métodos, permitió afirmar que 95,34 por ciento pertenecían a la var. neoformans y el resto (4,65 por ciento) a la var. gattii. Los resultados obtenidos corroboraronn que todos los aislamientos clínicos autóctonos, hasta el presente, corresponden a la var. neoformans y permitieron sugerir el uso de la D-prolina para la evaluación inicial de las cepas, como un método alternativo y sencillo que presentó, en estas condiciones, alta coincidencia con el método de referencia (crecimiento en CGB)

Obtención de antisueros específicos para la serotipificación de Cryptococcus neoformans var. neoformans / Obtention of specific antisera for the serotyping of Cryptococcus neoformans var. neoformans

Se propuso la obtención de antisueros en el Laboratorio de Micología del Instituto de Medicina Tropical ôPedro Kouríö, que permitiera la rápida identificación de las variedades y serotipos de Cryptococcus neoformans, dada la importancia clínico-epidemiológica que reviste su conocimiento. Mediante la inmunización de conejos con células enteras formalinizadas de los 4 serotipos de esta levadura, se obtuvieron antisueros que fueron adsorbidos con células de los serotipos heterólogos; lográndose 3 antisueros capaces de diferenciar a la var. neoformans (anti AD) y a sus respectivos serotipos (anti-A y anti-D). Este trabajo contribuirá al conocimiento de la epidemiología de esta importante enfermedad en el medio cubano, por ser la primera vez en Cuba que se logra la obtención de antisueros útiles para la identificación de los serotipos pertenecientes a la variedad neoformans, principal agente causal de la criptococosis