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

Contains fulltext : 124337.pdf (publisher's version ) (Open Access)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 Aalpha). 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

Resistance of Asian Cryptococcus neoformans Serotype A Is Confined to Few Microsatellite Genotypes

Contains fulltext : 109375.pdf (publisher's version ) (Open Access)BACKGROUND: Cryptococcus neoformans is a pathogenic yeast that causes cryptococcosis, a life threatening disease. The prevalence of cryptococcosis in Asia has been rising after the onset of the AIDS epidemic and estimates indicate more than 120 cases per 1,000 HIV-infected individuals per year. Almost all cryptococcal disease cases in both immunocompromised and immunocompetent patients in Asia are caused by C. neoformans var. grubii. Epidemiological studies on C. neoformans in pan-Asia have not been reported. The present work studies the genetic diversity of the fungus by microsatellite typing and susceptibility analysis of approximately 500 isolates from seven Asian countries. METHODOLOGY/PRINCIPAL FINDINGS: Genetic diversity of Asian isolates of C. neoformans was determined using microsatellite analysis with nine microsatellite markers. The analysis revealed eight microsatellite complexes (MCs) which showed different distributions among geographically defined populations. A correlation between MCs and HIV-status was observed. Microsatellite complex 2 was mainly associated with isolates from HIV-negative patients, whereas MC8 was associated with those from HIV-positive patients. Most isolates were susceptible to amphotericin B, itraconazole, voriconazole, posaconazole, and isavuconazole, but 17 (3.4%) and 10 (2%) were found to be resistant to 5-flucytosine and fluconazole, respectively. Importantly, five Indonesian isolates (approximately 12.5% from all Indonesian isolates investigated and 1% from the total studied isolates) were resistant to both antifungals. The majority of 5-flucytosine resistant isolates belonged to MC17. CONCLUSIONS: The findings showed a different distribution of genotypes of C. neoformans var. grubii isolates from various countries in Asia, as well as a correlation of the microsatellite genotypes with the original source of the strains and resistance to 5-flucytosine

Low diversity Cryptococcus neoformans variety grubii multilocus sequence types from Thailand are consistent with an ancestral African origin.

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Diagnóstico micológico en pacientes infectados por el Virus de la Inmunodefi ciencia Humana. Mycologic diagnosis in patients infected by VIH disease

Con el descubrimiento del virus de la inmunodefi ciencia humana (VIH) en 1981, la frecuencia de las infecciones oportunistas en pacientes inmunodeprimidos, especialmente los infectados por el VIH, ha experimentado un notable incremento.Dentro de éstas se encuentran las de etiología fúngica, las cuales presentan un alto grado de mortalidad si no son diagnosticadas y tratadas a tiempo. En nuestro país con la instauración de la terapia antirretroviral altamente efectiva a partir del año 2001, se ha notado una reducción signifi cativa en la morbilidad y la mortalidad por infecciones oportunistas, en particular por las micosis, muy comunes en este tipo de pacientes. En el presente estudio se realizó el diagnóstico micológico procedente de pacientes infectados por el VIH/sida, durante el período comprendido entre enero 2005 y diciembre de 2009. De un total de 1173 muestras biológicas procesadas, solamente resultaron positivas 324 para un 27,6% de positividad. La candidiasis orofaríngea y la meningoencefalitis criptococóccica fueron las infecciones diagnosticadas con una mayor incidencia. En las muestras analizadas la concordancia en la positividad entre el examen directo y el examen por cultivo micológico fue de un 56,2%, lo que confirma la importancia del empleo del examen directo en la visualización de estructuras fúngicas a partir de muestras clínicas.With the discovery of the human immunodefi ciency virus (HIV) in 1981, the frequency of the opportunistic infections in the immunosuppressed patients, especially the infected ones by the HIV, it has experienced a notable increase. Inside these there are those of micotic aetiology, which present a high grade of mortality, if they are not diagnosed and treated on time. In our country with the instauration of the highly effective antirretroviral therapy since the year 2001, a signifi cant reduction has been seen in the morbidity and the mortality of the opportunistic infections, specialle those caused by fungus, in this type of patients. In the present study the positividad was analyzed in the mycological diagnosis realized by conventional methods of the different clinical samples received in the National Laboratory of Reference of Mycology, from patients infected with HIV/aids during the period between January 2005 and December 2009. Of a whole of 1173 biological samples processed only 324 turned out positive, for 27, 6 % of positivity, being the oropharingeal candidiasis and the cryptococcal meningoencefalitis, those of major incidence observed. In the clinical samples analyzed, a concordance of 56,2 % was obtained in the positividad of the samples studied by means of direct examination and mycologycal cultures, which confi rms the importance of direct preparations of clinical samples for the visualization of fungal elements from clinical samples

Diagnóstico micológico en pacientes infectados por el Virus de la Inmunodeficiencia Humana

Con el descubrimiento del virus de la inmunodeficiencia humana (VIH) en 1981, la frecuencia de las infecciones oportunistas en pacientes inmunodeprimidos, especialmente los infectados por el VIH, ha experimentado un notable incremento.Dentro de éstas se encuentran las de etiología fúngica, las cuales presentan un alto grado de mortalidad si no son diagnosticadas y tratadas a tiempo. En nuestro país con la instauración de la terapia antirretroviral altamente efectiva a partir del año 2001, se ha notado una reducción significativa en la morbilidad y la mortalidad por infecciones oportunistas, en particular por las micosis, muy comunes en este tipo de pacientes. En el presente estudio se realizó el diagnóstico micológico procedente de pacientes infectados por el VIH/sida, durante el período comprendido entre enero 2005 y diciembre de 2009. De un total de 1173 muestras biológicas procesadas, solamente resultaron positivas 324 para un 27,6% de positividad. La candidiasis orofaríngea y la meningoencefalitis criptococóccica fueron las infecciones diagnosticadas con una mayor incidencia. En las muestras analizadas la concordancia en la positividad entre el examen directo y el examen por cultivo micológico fue de un 56,2%, lo que confirma la importancia del empleo del examen directo en la visualización de estructuras fúngicas a partir de muestras clínicas.With the discovery of the human immunodeficiency virus (HIV) in 1981, the frequency of the opportunistic infections in the immunosuppressed patients, especially the infected ones by the HIV, it has experienced a notable increase. Inside these there are those of micotic aetiology, which present a high grade of mortality, if they are not diagnosed and treated on time. In our country with the instauration of the highly effective antirretroviral therapy since the year 2001, a significant reduction has been seen in the morbidity and the mortality of the opportunistic infections, specialle those caused by fungus, in this type of patients. In the present study the positividad was analyzed in the mycological diagnosis realized by conventional methods of the different clinical samples received in the National Laboratory of Reference of Mycology, from patients infected with HIV/aids during the period between January 2005 and December 2009. Of a whole of 1173 biological samples processed only 324 turned out positive, for 27, 6 % of positivity, being the oropharingeal candidiasis and the cryptococcal meningoencefalitis, those of major incidence observed. In the clinical samples analyzed, a concordance of 56,2 % was obtained in the positividad of the samples studied by means of direct examination and mycologycal cultures, which confirms the importance of direct preparations of clinical samples for the visualization of fungal elements from clinical samples

Diagnóstico micológico en pacientes infectados por el Virus de la Inmunodeficiencia Humana

Con el descubrimiento del virus de la inmunodeficiencia humana (VIH) en 1981, la frecuencia de las infecciones oportunistas en pacientes inmunodeprimidos, especialmente los infectados por el VIH, ha experimentado un notable incremento.Dentro de éstas se encuentran las de etiología fúngica, las cuales presentan un alto grado de mortalidad si no son diagnosticadas y tratadas a tiempo. En nuestro país con la instauración de la terapia antirretroviral altamente efectiva a partir del año 2001, se ha notado una reducción significativa en la morbilidad y la mortalidad por infecciones oportunistas, en particular por las micosis, muy comunes en este tipo de pacientes. En el presente estudio se realizó el diagnóstico micológico procedente de pacientes infectados por el VIH/sida, durante el período comprendido entre enero 2005 y diciembre de 2009. De un total de 1173 muestras biológicas procesadas, solamente resultaron positivas 324 para un 27,6% de positividad. La candidiasis orofaríngea y la meningoencefalitis criptococóccica fueron las infecciones diagnosticadas con una mayor incidencia. En las muestras analizadas la concordancia en la positividad entre el examen directo y el examen por cultivo micológico fue de un 56,2%, lo que confirma la importancia del empleo del examen directo en la visualización de estructuras fúngicas a partir de muestras clínicas.With the discovery of the human immunodeficiency virus (HIV) in 1981, the frequency of the opportunistic infections in the immunosuppressed patients, especially the infected ones by the HIV, it has experienced a notable increase. Inside these there are those of micotic aetiology, which present a high grade of mortality, if they are not diagnosed and treated on time. In our country with the instauration of the highly effective antirretroviral therapy since the year 2001, a significant reduction has been seen in the morbidity and the mortality of the opportunistic infections, specialle those caused by fungus, in this type of patients. In the present study the positividad was analyzed in the mycological diagnosis realized by conventional methods of the different clinical samples received in the National Laboratory of Reference of Mycology, from patients infected with HIV/aids during the period between January 2005 and December 2009. Of a whole of 1173 biological samples processed only 324 turned out positive, for 27, 6 % of positivity, being the oropharingeal candidiasis and the cryptococcal meningoencefalitis, those of major incidence observed. In the clinical samples analyzed, a concordance of 56,2 % was obtained in the positividad of the samples studied by means of direct examination and mycologycal cultures, which confirms the importance of direct preparations of clinical samples for the visualization of fungal elements from clinical samples