Meningitis posquirúrgica por Acinetobacter baumannii multirresistente. Actividad sinérgica in vivo de la asociación sulbactam/avibactam / Post-surgical meningitis due to multiresistant Acinetobacter baumannii. In vivo synergistic activity of the sulbactam/avibactam association

Acinetobacter baumannii (AB) es un bacilo gram negativo, no fermentador,con frecuencia oportunista, ubicuo en el medio ambiente, con capacidad para sobrevivir en condiciones medioambientales adversas promoviendo su persistencia y diseminación en diferentes áreas de un hospital. Ha sido relacionado con múltiples brotes de infecciones asociadas al cuidado de la salud como neumonía, bacteriemias, contaminación de heridas quirúrgicas o infecciones del tracto urinario, especialmente entre pacientes con comorbilidades graves, como aquellos que motivan el ingreso a unidades de cuidados intensivos (UCI). Las cepas más problemáticas son aquellas resistentes a los carbapenémicos, resistencia causada por enzimas de la clase de las oxacilinasas (bla OXA) cromosómicas o plasmídicas y más recientemente bla NDM-1. La aparición de estas cepas deja escasos antimicrobianos activos (colistin, minociclina, tigeciclina; amikacina) que son limitados en su eficacia y su uso se asocia con toxicidad. A esto se agrega, como en la paciente que se describe, que desarrolló una meningitis posquirúrgica, la limitada capacidad de difusión en el sistema nervioso central (SNC) de estas últimas opciones. Una de las alternativas terapéuticas, es buscar asociaciones como sulbactam/avibactam que mostraron una adecuada actividad sinérgica y bactericida en asilamientos resistentes a ampicilina/sulbactam en base a una significativa reducción de la CIM que permite administrar dosis habituales, con mejor tolerancia y lograr concentraciones terapéuticas en SNC. Se presenta una paciente que desarrolló una meningitis posquirúrgica debida a una cepa de AB multirresistente.

Acinetobacter baumannii (AB) is a non-fermenting gram-negative bacillus, largely opportunistic, ubiquitous in the environment, with the ability to survive in adverse environmental conditions, promoting its persistence and dissemination in different areas of the hospital. It has been implicated in many outbreaks of healthcare-associated infections such as pneumonia, bacteremia, surgical wounds contamination, or urinary tract infections, especially among patients with previous severe illnesses such as those requiring admission to intensive care units (ICU). The most problematic strains are those resistant to carbapenems, resistance caused by chromosomal or plasmid oxacillinase class (bla OXA), and more recently bla NDM-1. The appearance of these strains leaves few active antimicrobials (Colistin, Minocycline, Tigecycline; Amikacin) that are limited in their efficacy and toxic. To this we must add, as is the case of our patient who presented post-surgical meningitis, the limited diffusion capacity in the central nervous system (CNS) of these last options. One of the therapeutic alternatives is to search for synergistic associations such as sulbactam/avibactam that showed rapid synergistic and bactericidal activity in isolates resistant to ampicillin/sulbactam due to a significant reduction in its MIC, which allows us to administer usual, better tolerated doses that reach therapeutic concentrations in CNS. Here, we present a patient who developed a post-surgical meningitis due to multiresistant AB

Analysis of serious non-AIDS events among HIV-infected adults at Latin American sites.

OBJECTIVE: Acquired immune deficiency appears to be associated with serious non-AIDS (SNA)-defining conditions such as cardiovascular disease, liver and renal insufficiency and non-AIDS-related malignancies. We analysed the incidence of, and factors associated with, several SNA events in the LATINA retrospective cohort. MATERIALS AND METHODS: Cases of SNA events were recorded among cohort patients. Three controls were selected for each case from cohort members at risk. Conditional logistic models were fitted to estimate the effect of traditional risk factors as well as HIV-associated factors on non-AIDS-defining conditions. RESULTS: Among 6007 patients in follow-up, 130 had an SNA event (0.86 events/100 person-years of follow-up) and were defined as cases (40 with cardiovascular events, 54 with serious liver failure, 35 with non-AIDS-defining malignancies and two with renal insufficiency). Risk factors such as diabetes, hepatitis B and C virus coinfections and alcohol abuse showed an association with events, as expected. The last recorded CD4 T-cell count prior to index date (P = 0.0056, with an average difference of more than 100 cells/µL) and area under the CD4 cell curve in the year previous to index date (P = 0.0081) were significantly lower in cases than in controls. CD4 cell count at index date was significantly associated with the outcome after adjusting for risk factors. CONCLUSIONS: The incidence and type of SNA events found in this Latin American cohort are similar to those reported in other regions. We found a significant association between immune deficiency and the risk of SNA events, even in patients under antiretroviral treatment.

Polyoma virus JC DNA detection by polymerase chain reaction in CSF of HIV infected patients with suspected progressive multifocal leukoencephalopathy.

Several studies had previously demonstrated the high sensitivity and specificity of JCV DNA detection in CSF by PCR. This paper reported the implementation of a simple PCR procedure to detect JCV in the CSF in a cohort of HIV-1 infected patients from Argentina. Years ago, the confirmatory diagnosis of this disease was made by in-situ hybridization or immunohistochemistry techniques on brain biopsies. The PCR procedure described here improves the diagnosis of PML because it is simple and noninvasive, and allows the differential diagnosis of PML from other neurological syndromes associated with AIDS. Many recent studies report a significant benefit of combined antiretroviral therapy on the survival of HIV patients without clear neurological improvements. A negative correlation has been described between the concentration of JCV in the CSF and survival time in HIV-1 infected patients, and the level of immune depression may influence JCV replication. This suggests that a single CSF JCV viral load determination during the course of PML disease progression may be of prognostic value for managing HIV patients.

[Detection of the viral load and its use as a virological marker in the follow-up of HIV-1-positive patients]. / Detección de la carga viral y su uso como marcador virológico en el seguimiento de pacientes HIV-1 positivos.

The evaluation of viral load as virological marker and its clinical and immunological correlation are presented. The first viral load studies were performed during 1996 at the National Reference Center for AIDS in Argentina in HIV-1 positive patients derived from different Hospitals in Buenos Aires. The study included 216 HIV-1 positive patients, 49 females and 167 males. Plasma was used for evaluating viral load and a second sample was obtained in 25 of the 216 patients for their monitoring. Viral load was performed using bDNA technique (Quantiplex HIV RNA assay 2.0, Chiron Corporation, USA). Other parameters such as CD4 count determined by flow cytometry and clinical stages according to CDC classification were obtained in order to correlate clinical and immunological status of the patients. When CD4 count was compared with viral load, the results showed a trend of viral RNA increase in plasma along with a decrease in CD4+ lymphocytes. This trend was also observed to correlate with the progression to AIDS disease. In all groups of patients, considering either CD4 counts or clinical status, ranges of viral load values were broad. Thus, as shown by percentiles 25 and 75, patients with CD4 counts < 200/ml, presented viral load values between 18,395 c/ml to 215,425 c/ml and patients with > 200/ml viral RNA showed values from < 10,000 to 35,180 c/ml. Patients with CDC's A and B stages presented values from < 10,000 to 45,160 c/ml and 87,000 c/ml respectively, while patients classified as C had 10,582 to 215,000 c/ml. Results of two consecutive samples in the 25 patients showed the usefulness of this technique for monitoring antiretroviral therapy. Nevertheless, despite the tendency of viral load to increase along with the progression of the disease, the broad range of values suggested the importance of using both virological and immunological parameters for the management of HIV infected patients.

Detección de la carga viral y su uso como marcador virológico en el seguimiento de pacientes HIV-1 positivos / Viral load detection and its role as virological marker for the monitoring of HIV-1 positive patients

Se realizaron los primeros estudios de carga viral en pacientes HIV-1 positivos provenientes de diferentes instituciones asistenciales de la Ciudad de Buenos Aires. Se evaluó la carga viral como marcador virológico y su correlación con la clínica y el recuento de los linfocitos CD4+ para 216 pacientes HIV-1 positivos. La técnica utilizada fue bDNA (Quantiplex HIV RNA 2.0 assay, Chiron Corporation). Se observó una tendencia al aumento de la carga viral en los pacientes con menor cantidad de linfocitos CD4+ y en los estadíos clínicos con sintomatología. En pacientes que no recibieron ninguna terapia antirretroviral se encontraron valores desde < 10000 copias de ARN viral/ml de plasma hasta 48995 c/ml. En aquéllos que recibieron terapia antirretroviral se observó mayor variación en los valores de la carga viral como lo mostró un rango de < 10000 c/ml hasta 96605 c/ml. Se obtuvieron muestras consecutivas en 25 pacientes y se observaron diferencias entre ambas muestras que permitieron corroborar la utilidad de la técnica en el seguimiento de los pacientes infectados con HIV