Colitis pseudomembranosa por Clostridium difficile: Reporte de un caso en paciente pediátrico. [Reporte de Caso] / Pseudomembranous colitis by Clostridium difficile infection: a case report in pediatric patient. [Case Report]

Clostridium difficile es un bacilo Gram positivo esporulado, anaerobio estricto, resistente a condiciones adversas y transmitido por vía oral-fecal, se describió por primera vez en 1930; sin embargo, se asoció a enfermedad en humanos en la década de los setenta al identificarse como agente causal de colitis pseudomembranosa. Esta infección se ha relacionado con diversas manifestaciones clínicas que van desde diarrea sin complicaciones hasta sepsis e incluso la muerte. Se presenta un caso clínico de un paciente masculino de 1 año 8 meses, con antecedentes de hipertermia y deposiciones líquidas abundantes, tras varios días de tratamiento antibiótico los síntomas se incrementaron con eliminación de resto membranoso en heces, se refiere a un hospital; donde se realiza el estudio de toxinas de Clostridium difficile, resultando positivo, por lo cual, se establece el diagnostico de colitis pseudomembranosa. Se administra metronidazol y vancomicina por 7 días, con una evolución favorable. El uso de antibióticos es un factor predisponente de colitis pseudomembranosa por la afectación de la microbiota intestinal; además de la estancia hospitalaria y factores intrínsecos. En la literatura se describe un número reducido de estudios sobre esta infección en pacientes pediátricos de allí la importancia del reporte de caso.

Clostridium difficile is a bacillus Gram positive and spore form, anaerobic strictly, resistant to adverse conditions and transmitted by oral - fecal route, it was described by the first time in 1930, nevertheless it's has been associated to disease in human beings in the decade of the seventies it identified as causal agent of pseudomembranous colitis. Its infection has related to diverse clinical manifestations such as diarrhea without complications, which lead to sepsis and inclusive the death. In the following clinical case we have a male infant 1 year old and 18 months patient, with precedents of hyperthermia and liquid depositions, after several days of antibiotics treatment, the symptoms increased with elimination of membranous rest in the faeces; reason why he is transferred to a hospital, in which the Clostridium difficile toxins test is realized, yielding positive results, therefore the diagnosis of pseudomembranous colitis is established metronidazole and vancomycin is given for 7 days having a favorable development. The use of antibiotics is a predisposing factor of pseudomembranous colitis for the affectation of the intestinal microbiota, in addition hospital stays and intrinsic factors. The literature describes a limited number of studies about this infection in pediatric patients, hence the importance of the case report

Rapid detection of ESBL-producing gram-negative bacteria isolated from blood: a reasonable and reliable tool for middle and low resource countries.

INTRODUCTION: Delay in appropriate treatment in patients with bacteraemia can increase morbidity, mortality, and health expenditures. We compared the Rapid Direct Test (RDT) designed to detect ESBL-producing gram-negative bacteria (GNB) directly from positive blood cultures bottles, with two conventional ESBL detection tests: Screening and Confirmatory Disk Diffusion Assay (SC-DDA) and an MIC Screening and ESBL E-test (MIC/ET). MATERIAL AND METHODS: We screened all blood cultures in a tertiary care facility from August to December 2005. We only included one positive bottle per patient in which GNB were observed. RDT: Blood from each bottle was inoculated on Mueller-Hinton agar. Ceftazidime and cefotaxime disks with and without clavulanic acid were added and incubated at 35 degrees C +/- 2 degrees C for 24 h. Results were interpreted according to CLSI recommendations for the SC-DDA and MIC/ET. All methods were performed simultaneously. Time for reporting as an ESBL-producer and cost of the tests were recorded. RESULTS: We isolated 124 GNB in 114 episodes of bacteraemia, 10 of them (8.8%) polymicrobial; 79 (63.7%) of the GNB were enteric bacteria, 44 (35.5%) glucose non-fermenter GNB and one Haemophilus influenzae. The most common microorganism was Escherichia coli in 56 episodes (45.2%), followed by Pseudomonas aeruginosa in 24 (19.3%), and Klebsiella pneumoniae in 13 (10.5%). Of the 114 episodes, 41 (36%) had at least one GNB resistant to 3rd generation cephalosporins, and 25 (21.9%) were caused by an ESBL-producing GNB. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the RDT were 96%, 98.9%, 96% and 98.9%, respectively. Agreement by kappa index between RDT and SC-DDA was 0.95 and between the RDT and MIC/ET was 0.92. The RDT detected 24/25 ESBL-producing bacteria. The mean time to detect an isolate as an ESBL producer after a positive blood culture bottle signal was 1.02 +/- 0.19 days when using the RDT, and 3.40 +/- 0.59 days when using any other method. The difference in reporting time was 2.38 +/- 0.63 days (p < 0.0001). Our estimated cost per test was $1.54 for RDT, $2.32 for screening/ confirmatory SC-DDA, and $49.65 for MIC screening and MIC/ET. Conclusions. The RDT is a rapid, reliable and easy analysis to perform, as well as cost-effective.

Endothelin-1 inhibits prostate cancer growth in vivo through vasoconstriction of tumor-feeding arterioles.

The vasoactive peptide endothelin-1 (ET-1) has been implicated in promoting the progression of prostate and other cancers though its precise mechanism(s)-of-action remain unclear. To better define the role of ET-1 in prostate cancer progression, we generated prostate cancer cell lines (PC-3 and 22Rv1) that express elevated levels of ET-1. As anticipated, increased ET-1 lead to modest autocrine growth stimulation of PC-3 cells in monolayer culture and increased colony formation in soft agar by both cell lines. Unexpectedly, however, metastatic colonization of 22Rv1 cells expressing elevated levels of ET-1 was reduced, as was the size of subcutaneous tumors produced by both 22Rv1- and PC-3 cells. Based on these data, we hypothesized that high levels of ET-1 may negatively impact the tumor microenvironment. We found that increased ET-1 expression did not consistently inhibit angiogenesis, indicating that this was not the cause of poor tumor growth. As an alternative explanation, we examined whether elevated ET-1 results in local vasoconstriction and thus reduces the blood supply available to the tumor. Consistent with this hypothesis, treatment of mice bearing PC-3 xenografts with a vasodilator increased tumor perfusion and partially restored tumor growth. Moreover, analysis of tumor vascular casts indicated vasoconstriction of tumor-feeding arterioles. Taken together, our data suggest that the local concentration of the ET-1 peptide is critical for determining a balance between its previously unrecognized tumor growth-suppressing activity (vasoconstriction) and known growth-promoting (mitogenesis, survival and angiogenesis) activities. These findings may have implications for the modification of current prostate cancer therapies involving ET-1.

Screening for tuberculosis in the study of the living renal donor in a developing country.

Given the high prevalence of tuberculosis (Tb) in the Mexican population, a strict program to detect Tb in the potential donor is required. Chest x-ray, excretory urogram, urinalysis with microscopic exam of the sediment, urine cultures for M. tuberculosis, and tuberculin skin test (TST) with PPD-RT23 performed for evaluation of 222 living donors were reviewed. Isoniazid prophylaxis before kidney donation was gathered. Donors and recipients were followed up for a minimum of 2 years. According to the TST result, 36.8% of the donors had latent tuberculosis; however, all other studies were normal or negative in all of them. Use of isoniazid prophylaxis in TST-positive donors made no difference in risk of transmission of tuberculosis to the recipient or development of tuberculosis among the donors. Normal chest x-ray and excretory urogram, along with a negative microscopic examination of the urine, safely exclude tuberculosis transmission to recipients.