Sara Kaufman - Academia.edu (original) (raw)
Papers by Sara Kaufman
[Comparison of methods for the identification of the most common yeasts in the clinical microbiology laboratory]
PubMed, Jul 2, 2003
We evaluated different methods for the routine identification of medically important yeasts. A to... more We evaluated different methods for the routine identification of medically important yeasts. A total of 150 clinical isolates: 25 C. albicans, 25 C. tropicalis, 25 C. glabrata, 25 C. parapsilosis, 8 C. guilliermondii, 11 C. krusei and 31 Cryptococcus neoformans were tested by Yeast Biochemical Card bioMerieux Vitek (YBC), CHROMagar Candida (CHR). The addition of yeast morphology in Corn Meal agar-Tween 80 (AM) to YBC and CHR was also evaluated. The reference methods used were: API 20C, germ tube formation, AM, Christensen urea and Birdseed agar. YBC identified 135 yeasts with an overall accuracy of 90%. Sensitivity (S) and specificity (E) were: 92-98% for C. albicans and C. tropicalis; 84-99% for C. papapsilosis; 100-99% for C. glabrata; 91-100% for C. krusei; 63-98% for C. guilliermondii and 90-99% for Cryptococcus neoformans, respectively. CHR identified correctly 100% for C. albicans, 92% for C. tropicalis and 91% for C. krusei. Both methods combined with AM provided 100% S and E. We found that YBC system was appropriate for identification of yeasts isolated from human sources. CHR was effective and easy to use for identification of C. albicans, C. tropicalis and C. krusei. The routine use of AM with both methods is recommended.
Disseminated histoplasmosis with orofacial involvement in HIV-1-infected patients with AIDS: manifestations and treatment
Oral Diseases, Jun 28, 2008
INTRODUCTION: Histoplasmosis is a deep mycosis which is increasingly seen in HIV disease. It has ... more INTRODUCTION: Histoplasmosis is a deep mycosis which is increasingly seen in HIV disease. It has emerged as a relatively common infection in Argentina, mainly in HIV‐infected and other immunocompromised persons, and is often disseminated (DH).OBJECTIVE: The aim of this study was to describe 32 HIV‐1‐seropositive patients with AIDS who had DH, 21 of whom presented orofacial manifestations, and their treatment.SUBJECTS AND METHODS: A retrospective study of 876 HIV‐seropositive patients revealed 32 with a clinical diagnosis of DH confirmed by special stains on histo‐pathologic specimens, or by culture.RESULTS: Thirty‐two HIV‐infected patients had DH. Two‐thirds (21 patients) had oral lesions of histoplasmosis, of which six presented with oral cavity (OC) lesions as the sole orofacial manifestation of disease, nine patients presented oral and facial (OF) lesions and six presented facial lesions only. A unique case of submandibular histoplasmosis is also reported. Antifungal therapy cleared more than 90% of the orofacial and disseminated lesions of histoplasmosiS. Over the 7‐year period there was a mortality of 85%.CONCLUSION: DH should be considered as a possible diagnosis in HIV patients with chronic ulcerative or nodular orofacial or oral lesionS. Itraconazole is an effective and acceptable therapy.
[Infective endocarditis and drug addiction]
PubMed, 1994
A total of 103 patients (P) with infectious endocarditis (IE) were treated during the period 1982... more A total of 103 patients (P) with infectious endocarditis (IE) were treated during the period 1982-1993; 72% of them were male. Mean age was 46.4 (SD 19.7). Eighteen patients were intravenous drug addicts (D) (17.5%). The first case of drug addiction in the IE group was seen in 1986; since then, there was a steady increase of this condition, reaching 50% of all cases. The average age of D patients was 28.17 +/- 8.15 years significantly lower than that corresponding to non-drug addicts (ND), 48.64 +/- 19.5 (p < 0.00001). The infection was located mainly in the left heart of the ND (93%), and in the right heart of the D (78%), the difference being statistically significant. All the cases of left IE occurred on previously damaged valves. Right location in ND was found in all cases in immunosuppressed individuals being treated for systemic diseases, except in one patient having an endocavitary pacemaker. No differences were found between ND and D with regard to the presence of fever, cutaneous manifestations, splenomegaly or cerebrovascular accident. Differences were noted, however, in the case of respiratory involvement, which showed a significantly higher frequency in D (38.9% versus 12.9%; p < 0.014). Blood cultures were positive in 81.6% of the total number of patients, no difference being found between the two groups. Staphylococcal infections were predominant in D (44%) and streptococcal infections in ND (48%), the difference being statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)
Medical Mycology, 2007
Trichosporon asahii is an opportunistic fungus considered the leading etiologic agent of trichosp... more Trichosporon asahii is an opportunistic fungus considered the leading etiologic agent of trichospornosis, a disease that causes great morbidity/mortality among affected patients. The identification of the etiologic agent is generally obtained through physiological and morphological studies. Molecular investigations, such as species-specific primers (PCR), have recently been developed with the aim of applying a more simple, specific, and faster technology for mycological diagnosis. The genetic material amplification technique using ad-random primers (RAPD: random amplified polymorphic DNA) is an epidemiological tool which enables research on infection by and transmission of suspected agents. In this study, the amplified polymorphic DNA technique was used to determine the intraspecific diversity of 10 Trichosporon asahii strains. Primers OPAO-15 and 1821 were used and these allowed association to 5 and 3 electrophoretic patterns, respectively. The T. asahii molecular identification, which had been previously analyzed by conventional methods, was performed by means of primers TAAF and pITS4. Our results support the use of these techniques for clonality studies of the strains of this fungus as well as for the fast and specific identification of its members in clinical cases.
Medical Mycology, 2000
Infection with Cryptococcus neoformans is an increasing problem in immunocompromised patients, pa... more Infection with Cryptococcus neoformans is an increasing problem in immunocompromised patients, particularly those with acquired immune de ciency syndrome (AIDS). Amphotericin B and uconazole are currently acceptable therapies for cryptococcal meningitis; however, their effects remain suboptimal and recurrence or treatment failure is still a problem. Antifungal susceptibility testing may be an important tool for guiding therapy, but for C. neoformans, a reliable method is still not available. This retrospective study evaluated minimal inhibitory concentration (MIC) for amphotericin B and uconazole, and minimal fungicidal concentration (MFC) and timed-kill curves for amphotericin B against 16 clinical isolates of C. neoformans obtained from AIDS patients with cryptococcal meningitis. No correlation between clinical outcome and MIC was observed for amphotericin B. In selected cases, the MFC seemed to be a better predictor of outcome than MIC. In this study, amphotericin B timed-kill curves appeared to show a correlation with clinical outcome of the 16 patients with AIDS-associated cryptococcal meningitis. These in ×itro tests must be further evaluated in prospective studies to con rm their potential usefulness for guiding cryptococcal meningitis therapy.
Journal of Antimicrobial Chemotherapy, 2000
[Diarrhea and AIDS: more complex diagnostic techniques; better therapeutic results]
Acta gastroenterologica Latinoamericana, 1996
During 17 months, 73 HIV-positive patients with diarrhea lasting at least for 14 days, were studi... more During 17 months, 73 HIV-positive patients with diarrhea lasting at least for 14 days, were studied prospectively. The patients had stool specimen examinations negative for enteric pathogens, or positive for one of them, but with no response to specific treatment. All patients were subcomitted to digestive endoscopy and biopsies were taken for microbiological and histological studies. The etiology of the diarrhea could be established in 48 patients (66%). In 45, the cause was an enteric infection. There was association of 2 pathogens in 11 patients, and of 3 in 1 patient. The agents found were: Cryptosporidium (24%), MAI (16%), Giardia lambila (12%), isospora belli (5%), Shigella (5%), Salmonella (5%); Entamoeba histolytica (3%), HSV (3%), tuberculosis (2%), adherent bacteria (2%) and spirochetes (2%). In 3 patients the etiology was not infection, their diagnoses were coeliac disease, lymphoma and idiophatic colonic ulcers, respectively. In 51% of the cases only the examination of e...
Beta-lactam antibiotics and viridans group streptococci
Revista Argentina de Microbiología
Acta gastroenterologica Latinoamericana, 2007
Coinfection with hepatitis C virus (HCV) in individuals infected with HIV is associated with a hi... more Coinfection with hepatitis C virus (HCV) in individuals infected with HIV is associated with a higher incidence of liver injury hepatic decompensation, and decreased survival than that observed in an HIV-monoinfected population. While prevalence studies on HIV/HCV coinfection have been performed in the U.S. and in some European countries, little is known about HCV genotype distribution in Latin America. The main objective was to evaluate the HCV prevalence and genotypes among HIV co-infected patients, and their relationship with HCV viral load, serum ALT level and T lymphocyte CD4+ cell count. These data pursue to increase the knowledge from South America about a pressing problem from HIV-infected patients. Retrospectively collected specimens from 593 HIV-positive individuals in Argentina were tested for anti-HCV These were analyzed for HCV-RNA qualitatively and quantitatively. The HCV genotype was determined by the RFLP method. One hundred and twenty-nine (21.7%) HIV-infected indiv...
Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of grow... more Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P.Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates d...
Medicina, 2004
Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of grow... more Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P. Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates ...
Revista Argentina de Microbiología, 2021
Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremi... more Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremia, and otitis media. Penicillin resistance rates in S. pneumoniae have remained stable in Argentina in the last years. In the late '90s more isolates with MIC of penicillin ≥2 g/ml were observed; however, their frequency has decreased in recent years. The phenotypic expression of penicillin resistance is due to a modification in penicillin-binding proteins associated with a mosaic structure in the coding genes. The expansion of successful resistant clones varies among the different regions and is influenced by the use of antibiotics, vaccines, particularly conjugated ones, as well as population density. Parenteral treatment with high doses of penicillin G continues to be effective for the treatment of pneumonia and bacteremia, oral aminopenicillins for otitis media and sinusitis and third generation cephalosporins for meningitis.
Revista Argentina de Microbiología, 2021
Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremi... more Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremia, and otitis media. Penicillin resistance rates in S. pneumoniae have remained stable in Argentina in the last years. In the late '90s more isolates with MIC of penicillin ≥2 g/ml were observed; however, their frequency has decreased in recent years. The phenotypic expression of penicillin resistance is due to a modification in penicillin-binding proteins associated with a mosaic structure in the coding genes. The expansion of successful resistant clones varies among the different regions and is influenced by the use of antibiotics, vaccines, particularly conjugated ones, as well as population density. Parenteral treatment with high doses of penicillin G continues to be effective for the treatment of pneumonia and bacteremia, oral aminopenicillins for otitis media and sinusitis and third generation cephalosporins for meningitis.
Revista Argentina de Microbiología, 2018
Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espec... more Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espectrometría de masas Resumen Las micobacterias de crecimiento rápido son una rara causa de endocarditis bacteriana. Durante las últimas décadas han aumentado las infecciones debido a este tipo de micobacterias, en especial las postraumáticas y las posquirúrgicas. Estas infecciones pueden ser localizadas o diseminadas, y también pueden producir brotes nosocomiales debido a la contaminación del equipamiento médico. Por lo general, las tinciones para bacterias ácidoalcohol resistentes no se emplean de rutina en el procesamiento de hemocultivos positivos. Sin embargo, el microbiólogo debe estar atento al ver un bacilo gram positivo, ya que podría tratarse de una micobacteria de crecimiento rápido. Describimos un caso de endocarditis por Mycobacterium mageritense en una paciente con parche pericárdico autógeno y un catéter para medir la presión en la aurícula izquierda. La bacteria fue identificada por espectrometría de masas (MALDI-TOF MS), score 2,3, y luego confirmada por secuenciación y análisis del gen ARNr 16s con las bases de datos del NCBI y EzTaxon, con una concordancia del 99,8 y el 100%, respectivamente.
Revista Argentina de Microbiología, 2018
Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espec... more Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espectrometría de masas Resumen Las micobacterias de crecimiento rápido son una rara causa de endocarditis bacteriana. Durante las últimas décadas han aumentado las infecciones debido a este tipo de micobacterias, en especial las postraumáticas y las posquirúrgicas. Estas infecciones pueden ser localizadas o diseminadas, y también pueden producir brotes nosocomiales debido a la contaminación del equipamiento médico. Por lo general, las tinciones para bacterias ácidoalcohol resistentes no se emplean de rutina en el procesamiento de hemocultivos positivos. Sin embargo, el microbiólogo debe estar atento al ver un bacilo gram positivo, ya que podría tratarse de una micobacteria de crecimiento rápido. Describimos un caso de endocarditis por Mycobacterium mageritense en una paciente con parche pericárdico autógeno y un catéter para medir la presión en la aurícula izquierda. La bacteria fue identificada por espectrometría de masas (MALDI-TOF MS), score 2,3, y luego confirmada por secuenciación y análisis del gen ARNr 16s con las bases de datos del NCBI y EzTaxon, con una concordancia del 99,8 y el 100%, respectivamente.
Revista Argentina de microbiologia, Jan 13, 2018
Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogen... more Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attributable to different causes. By contrast, some GBS with reduced susceptibility to penicillin have been described, especially in Japan. In this group of bacteria, it is important to highlight that confirmation by reference methods is mandatory when decreased susceptibility to penicillin is suspected as well as checked for the detection of the mechanisms involved.
![Research paper thumbnail of [Mycoplasma hominis bacteremia. An underestimated etiological agent]](https://attachments.academia-assets.com/88299001/thumbnails/1.jpg)
](Revista Argentina de microbiologia, Jan 17, 2017
Mycoplasma hominis is a fastidious bacterium, which usually colonizes the lower urogenital tract ... more Mycoplasma hominis is a fastidious bacterium, which usually colonizes the lower urogenital tract and may cause systemic infections in neonates and genital infections in adults. It can also be the cause of serious extra-genital infections, mainly in immunosuppressed or predisposed subjects. We describe a case of bacteremia caused by M. hominis in a previously healthy woman after uterine curettage due to incomplete abortion. M. hominis could be an underestimated cause of bacteremia in immunocompetent patients. Mycoplasma organisms have fastidious growth requirements, are often difficult to culture on a cell-free medium and have no cell wall. The conventional method for detection may fail. This is the first report of M. hominis isolation from a positive automated blood culture (BD BACTEC, USA).
PloS one, 2017
Globally, Latin America ranks third among regions with most cases of AIDS related cryptococcal me... more Globally, Latin America ranks third among regions with most cases of AIDS related cryptococcal meningitis. In 2009, a lateral flow immunoassay (LFA) for the detection of cryptococcal antigen (CrAg) was developed as a potential point-of-care test for diagnosis of cryptococcal infection. In 2011 World Health Organizations recommended on CrAg screening for HIV positive persons with CD4 below 100 cells/μL, followed by preemptive fluconazole treatment. However, in Argentina no formal recommendations for CrAg screening have been issued. HIV positive patients > = 18 years with advanced immunosuppression (CD4 counts ≤100 cells/μL within 3 months or WHO stage III/IV), who visited the hospital between April 1, 2014 and January 31, 2015, were included. The LFA was performed according to the manufacturer's instructions on all serum samples. When CrAg detection was positive, a lumbar puncture was performed to rule out cryptococcal meningitis. Patients without evidence of meningeal involve...
Antibiotic Sensitivity of Nocardia Species in Argentina
Síndrome febril prolongado e infección de aneurisma de aorta abdominal por Salmonella enteritidis
Medicina, 1995
[Comparison of methods for the identification of the most common yeasts in the clinical microbiology laboratory]
PubMed, Jul 2, 2003
We evaluated different methods for the routine identification of medically important yeasts. A to... more We evaluated different methods for the routine identification of medically important yeasts. A total of 150 clinical isolates: 25 C. albicans, 25 C. tropicalis, 25 C. glabrata, 25 C. parapsilosis, 8 C. guilliermondii, 11 C. krusei and 31 Cryptococcus neoformans were tested by Yeast Biochemical Card bioMerieux Vitek (YBC), CHROMagar Candida (CHR). The addition of yeast morphology in Corn Meal agar-Tween 80 (AM) to YBC and CHR was also evaluated. The reference methods used were: API 20C, germ tube formation, AM, Christensen urea and Birdseed agar. YBC identified 135 yeasts with an overall accuracy of 90%. Sensitivity (S) and specificity (E) were: 92-98% for C. albicans and C. tropicalis; 84-99% for C. papapsilosis; 100-99% for C. glabrata; 91-100% for C. krusei; 63-98% for C. guilliermondii and 90-99% for Cryptococcus neoformans, respectively. CHR identified correctly 100% for C. albicans, 92% for C. tropicalis and 91% for C. krusei. Both methods combined with AM provided 100% S and E. We found that YBC system was appropriate for identification of yeasts isolated from human sources. CHR was effective and easy to use for identification of C. albicans, C. tropicalis and C. krusei. The routine use of AM with both methods is recommended.
Disseminated histoplasmosis with orofacial involvement in HIV-1-infected patients with AIDS: manifestations and treatment
Oral Diseases, Jun 28, 2008
INTRODUCTION: Histoplasmosis is a deep mycosis which is increasingly seen in HIV disease. It has ... more INTRODUCTION: Histoplasmosis is a deep mycosis which is increasingly seen in HIV disease. It has emerged as a relatively common infection in Argentina, mainly in HIV‐infected and other immunocompromised persons, and is often disseminated (DH).OBJECTIVE: The aim of this study was to describe 32 HIV‐1‐seropositive patients with AIDS who had DH, 21 of whom presented orofacial manifestations, and their treatment.SUBJECTS AND METHODS: A retrospective study of 876 HIV‐seropositive patients revealed 32 with a clinical diagnosis of DH confirmed by special stains on histo‐pathologic specimens, or by culture.RESULTS: Thirty‐two HIV‐infected patients had DH. Two‐thirds (21 patients) had oral lesions of histoplasmosis, of which six presented with oral cavity (OC) lesions as the sole orofacial manifestation of disease, nine patients presented oral and facial (OF) lesions and six presented facial lesions only. A unique case of submandibular histoplasmosis is also reported. Antifungal therapy cleared more than 90% of the orofacial and disseminated lesions of histoplasmosiS. Over the 7‐year period there was a mortality of 85%.CONCLUSION: DH should be considered as a possible diagnosis in HIV patients with chronic ulcerative or nodular orofacial or oral lesionS. Itraconazole is an effective and acceptable therapy.
[Infective endocarditis and drug addiction]
PubMed, 1994
A total of 103 patients (P) with infectious endocarditis (IE) were treated during the period 1982... more A total of 103 patients (P) with infectious endocarditis (IE) were treated during the period 1982-1993; 72% of them were male. Mean age was 46.4 (SD 19.7). Eighteen patients were intravenous drug addicts (D) (17.5%). The first case of drug addiction in the IE group was seen in 1986; since then, there was a steady increase of this condition, reaching 50% of all cases. The average age of D patients was 28.17 +/- 8.15 years significantly lower than that corresponding to non-drug addicts (ND), 48.64 +/- 19.5 (p < 0.00001). The infection was located mainly in the left heart of the ND (93%), and in the right heart of the D (78%), the difference being statistically significant. All the cases of left IE occurred on previously damaged valves. Right location in ND was found in all cases in immunosuppressed individuals being treated for systemic diseases, except in one patient having an endocavitary pacemaker. No differences were found between ND and D with regard to the presence of fever, cutaneous manifestations, splenomegaly or cerebrovascular accident. Differences were noted, however, in the case of respiratory involvement, which showed a significantly higher frequency in D (38.9% versus 12.9%; p < 0.014). Blood cultures were positive in 81.6% of the total number of patients, no difference being found between the two groups. Staphylococcal infections were predominant in D (44%) and streptococcal infections in ND (48%), the difference being statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)
Medical Mycology, 2007
Trichosporon asahii is an opportunistic fungus considered the leading etiologic agent of trichosp... more Trichosporon asahii is an opportunistic fungus considered the leading etiologic agent of trichospornosis, a disease that causes great morbidity/mortality among affected patients. The identification of the etiologic agent is generally obtained through physiological and morphological studies. Molecular investigations, such as species-specific primers (PCR), have recently been developed with the aim of applying a more simple, specific, and faster technology for mycological diagnosis. The genetic material amplification technique using ad-random primers (RAPD: random amplified polymorphic DNA) is an epidemiological tool which enables research on infection by and transmission of suspected agents. In this study, the amplified polymorphic DNA technique was used to determine the intraspecific diversity of 10 Trichosporon asahii strains. Primers OPAO-15 and 1821 were used and these allowed association to 5 and 3 electrophoretic patterns, respectively. The T. asahii molecular identification, which had been previously analyzed by conventional methods, was performed by means of primers TAAF and pITS4. Our results support the use of these techniques for clonality studies of the strains of this fungus as well as for the fast and specific identification of its members in clinical cases.
Medical Mycology, 2000
Infection with Cryptococcus neoformans is an increasing problem in immunocompromised patients, pa... more Infection with Cryptococcus neoformans is an increasing problem in immunocompromised patients, particularly those with acquired immune de ciency syndrome (AIDS). Amphotericin B and uconazole are currently acceptable therapies for cryptococcal meningitis; however, their effects remain suboptimal and recurrence or treatment failure is still a problem. Antifungal susceptibility testing may be an important tool for guiding therapy, but for C. neoformans, a reliable method is still not available. This retrospective study evaluated minimal inhibitory concentration (MIC) for amphotericin B and uconazole, and minimal fungicidal concentration (MFC) and timed-kill curves for amphotericin B against 16 clinical isolates of C. neoformans obtained from AIDS patients with cryptococcal meningitis. No correlation between clinical outcome and MIC was observed for amphotericin B. In selected cases, the MFC seemed to be a better predictor of outcome than MIC. In this study, amphotericin B timed-kill curves appeared to show a correlation with clinical outcome of the 16 patients with AIDS-associated cryptococcal meningitis. These in ×itro tests must be further evaluated in prospective studies to con rm their potential usefulness for guiding cryptococcal meningitis therapy.
Journal of Antimicrobial Chemotherapy, 2000
[Diarrhea and AIDS: more complex diagnostic techniques; better therapeutic results]
Acta gastroenterologica Latinoamericana, 1996
During 17 months, 73 HIV-positive patients with diarrhea lasting at least for 14 days, were studi... more During 17 months, 73 HIV-positive patients with diarrhea lasting at least for 14 days, were studied prospectively. The patients had stool specimen examinations negative for enteric pathogens, or positive for one of them, but with no response to specific treatment. All patients were subcomitted to digestive endoscopy and biopsies were taken for microbiological and histological studies. The etiology of the diarrhea could be established in 48 patients (66%). In 45, the cause was an enteric infection. There was association of 2 pathogens in 11 patients, and of 3 in 1 patient. The agents found were: Cryptosporidium (24%), MAI (16%), Giardia lambila (12%), isospora belli (5%), Shigella (5%), Salmonella (5%); Entamoeba histolytica (3%), HSV (3%), tuberculosis (2%), adherent bacteria (2%) and spirochetes (2%). In 3 patients the etiology was not infection, their diagnoses were coeliac disease, lymphoma and idiophatic colonic ulcers, respectively. In 51% of the cases only the examination of e...
Beta-lactam antibiotics and viridans group streptococci
Revista Argentina de Microbiología
Acta gastroenterologica Latinoamericana, 2007
Coinfection with hepatitis C virus (HCV) in individuals infected with HIV is associated with a hi... more Coinfection with hepatitis C virus (HCV) in individuals infected with HIV is associated with a higher incidence of liver injury hepatic decompensation, and decreased survival than that observed in an HIV-monoinfected population. While prevalence studies on HIV/HCV coinfection have been performed in the U.S. and in some European countries, little is known about HCV genotype distribution in Latin America. The main objective was to evaluate the HCV prevalence and genotypes among HIV co-infected patients, and their relationship with HCV viral load, serum ALT level and T lymphocyte CD4+ cell count. These data pursue to increase the knowledge from South America about a pressing problem from HIV-infected patients. Retrospectively collected specimens from 593 HIV-positive individuals in Argentina were tested for anti-HCV These were analyzed for HCV-RNA qualitatively and quantitatively. The HCV genotype was determined by the RFLP method. One hundred and twenty-nine (21.7%) HIV-infected indiv...
Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of grow... more Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P.Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates d...
Medicina, 2004
Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of grow... more Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P. Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates ...
Revista Argentina de Microbiología, 2021
Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremi... more Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremia, and otitis media. Penicillin resistance rates in S. pneumoniae have remained stable in Argentina in the last years. In the late '90s more isolates with MIC of penicillin ≥2 g/ml were observed; however, their frequency has decreased in recent years. The phenotypic expression of penicillin resistance is due to a modification in penicillin-binding proteins associated with a mosaic structure in the coding genes. The expansion of successful resistant clones varies among the different regions and is influenced by the use of antibiotics, vaccines, particularly conjugated ones, as well as population density. Parenteral treatment with high doses of penicillin G continues to be effective for the treatment of pneumonia and bacteremia, oral aminopenicillins for otitis media and sinusitis and third generation cephalosporins for meningitis.
Revista Argentina de Microbiología, 2021
Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremi... more Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremia, and otitis media. Penicillin resistance rates in S. pneumoniae have remained stable in Argentina in the last years. In the late '90s more isolates with MIC of penicillin ≥2 g/ml were observed; however, their frequency has decreased in recent years. The phenotypic expression of penicillin resistance is due to a modification in penicillin-binding proteins associated with a mosaic structure in the coding genes. The expansion of successful resistant clones varies among the different regions and is influenced by the use of antibiotics, vaccines, particularly conjugated ones, as well as population density. Parenteral treatment with high doses of penicillin G continues to be effective for the treatment of pneumonia and bacteremia, oral aminopenicillins for otitis media and sinusitis and third generation cephalosporins for meningitis.
Revista Argentina de Microbiología, 2018
Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espec... more Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espectrometría de masas Resumen Las micobacterias de crecimiento rápido son una rara causa de endocarditis bacteriana. Durante las últimas décadas han aumentado las infecciones debido a este tipo de micobacterias, en especial las postraumáticas y las posquirúrgicas. Estas infecciones pueden ser localizadas o diseminadas, y también pueden producir brotes nosocomiales debido a la contaminación del equipamiento médico. Por lo general, las tinciones para bacterias ácidoalcohol resistentes no se emplean de rutina en el procesamiento de hemocultivos positivos. Sin embargo, el microbiólogo debe estar atento al ver un bacilo gram positivo, ya que podría tratarse de una micobacteria de crecimiento rápido. Describimos un caso de endocarditis por Mycobacterium mageritense en una paciente con parche pericárdico autógeno y un catéter para medir la presión en la aurícula izquierda. La bacteria fue identificada por espectrometría de masas (MALDI-TOF MS), score 2,3, y luego confirmada por secuenciación y análisis del gen ARNr 16s con las bases de datos del NCBI y EzTaxon, con una concordancia del 99,8 y el 100%, respectivamente.
Revista Argentina de Microbiología, 2018
Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espec... more Endocarditis infecciosa; Dispositivo cardiovascular electrónico; Mycobacterium mageritense; Espectrometría de masas Resumen Las micobacterias de crecimiento rápido son una rara causa de endocarditis bacteriana. Durante las últimas décadas han aumentado las infecciones debido a este tipo de micobacterias, en especial las postraumáticas y las posquirúrgicas. Estas infecciones pueden ser localizadas o diseminadas, y también pueden producir brotes nosocomiales debido a la contaminación del equipamiento médico. Por lo general, las tinciones para bacterias ácidoalcohol resistentes no se emplean de rutina en el procesamiento de hemocultivos positivos. Sin embargo, el microbiólogo debe estar atento al ver un bacilo gram positivo, ya que podría tratarse de una micobacteria de crecimiento rápido. Describimos un caso de endocarditis por Mycobacterium mageritense en una paciente con parche pericárdico autógeno y un catéter para medir la presión en la aurícula izquierda. La bacteria fue identificada por espectrometría de masas (MALDI-TOF MS), score 2,3, y luego confirmada por secuenciación y análisis del gen ARNr 16s con las bases de datos del NCBI y EzTaxon, con una concordancia del 99,8 y el 100%, respectivamente.
Revista Argentina de microbiologia, Jan 13, 2018
Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogen... more Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attributable to different causes. By contrast, some GBS with reduced susceptibility to penicillin have been described, especially in Japan. In this group of bacteria, it is important to highlight that confirmation by reference methods is mandatory when decreased susceptibility to penicillin is suspected as well as checked for the detection of the mechanisms involved.
Revista Argentina de microbiologia, Jan 17, 2017
Mycoplasma hominis is a fastidious bacterium, which usually colonizes the lower urogenital tract ... more Mycoplasma hominis is a fastidious bacterium, which usually colonizes the lower urogenital tract and may cause systemic infections in neonates and genital infections in adults. It can also be the cause of serious extra-genital infections, mainly in immunosuppressed or predisposed subjects. We describe a case of bacteremia caused by M. hominis in a previously healthy woman after uterine curettage due to incomplete abortion. M. hominis could be an underestimated cause of bacteremia in immunocompetent patients. Mycoplasma organisms have fastidious growth requirements, are often difficult to culture on a cell-free medium and have no cell wall. The conventional method for detection may fail. This is the first report of M. hominis isolation from a positive automated blood culture (BD BACTEC, USA).
PloS one, 2017
Globally, Latin America ranks third among regions with most cases of AIDS related cryptococcal me... more Globally, Latin America ranks third among regions with most cases of AIDS related cryptococcal meningitis. In 2009, a lateral flow immunoassay (LFA) for the detection of cryptococcal antigen (CrAg) was developed as a potential point-of-care test for diagnosis of cryptococcal infection. In 2011 World Health Organizations recommended on CrAg screening for HIV positive persons with CD4 below 100 cells/μL, followed by preemptive fluconazole treatment. However, in Argentina no formal recommendations for CrAg screening have been issued. HIV positive patients > = 18 years with advanced immunosuppression (CD4 counts ≤100 cells/μL within 3 months or WHO stage III/IV), who visited the hospital between April 1, 2014 and January 31, 2015, were included. The LFA was performed according to the manufacturer's instructions on all serum samples. When CrAg detection was positive, a lumbar puncture was performed to rule out cryptococcal meningitis. Patients without evidence of meningeal involve...
Antibiotic Sensitivity of Nocardia Species in Argentina
Síndrome febril prolongado e infección de aneurisma de aorta abdominal por Salmonella enteritidis
Medicina, 1995