[Translated article] Immediate standing X-ray predicts the final vertebral collapse in elderly patients with thoracolumbar burst fracture.

OBJECTIVE: To see if, in elderly patients with traumatic thoracolumbar fracture, standing X-rays with orthoses 24-48h after admission can predict vertebral collapse after consolidation. MATERIAL AND METHODS: Prospective cohort study endorsed by the Clinical Research Ethics Committee. INCLUSION CRITERIA: age >65 years, acute thoracolumbar junction fracture due to fall, hospital admission, treatment with orthesis. EXCLUSION CRITERIA: various levels, suspected malignancy, non-immediate fracture or atraumatic. VARIABLES: Farcy index (F), regional kyphosis (C: Cobb from cranial to caudal to broken vertebra) - both measured at admission (F0 and C0), at 24-48h in standing position with orthesis (F1 and C1) and 3 months, without brace (F2 and C2), collapse (increase from F0 to F1 -F0F1- and from F1 to F2 -F1F2-; as well as from C0 to C1 -C0C1- and from C1 to C2 -C1C2-), age and gender. STATISTICAL ANALYSIS: R package. RESULTS: Series of 40 patients, with a mean age of 75 years (66-87). Nine men and 31 women. Neither gender nor age were correlated with any variable. Six required surgery at follow-up. There were no differences in F1, C1, F0F1 or C0C1 between the six patients who required surgery and the other 34. Subsequently, data analysis was performed only for those patients who did not require surgery. The values obtained in the Farcy index were 8°+7° (F0), 12°+7° (F1) and 15°+8° (F2) and in kyphosis (three vertebrae, Cobb) they were: C0=8°+13°; C1=11.5°+14° and C2=13°+13°. There was a correlation of F2 with F0 and F1 (p<.001), with F0F1 (p=.038) and F1F2 (p=.007). The most powerful was with F1 (Rho Spearman=.889, 95% CI=.776-.947), with a linear regression line: F2=2.61288+F1×1.01237 (R2=.79). C2 was correlated with C0 and C1 (p<.001), especially with C1 (Rho Spearman=.952, 95% CI=.899-.977). Linear regression: C2=2.23371+C1×0.93758 (R2=.927). CONCLUSIONS: Immediate standing collapse predicts alignment at consolidation (3 months). It is therefore advisable to perform that radiography in the follow-up protocol.

Immediate standing X-ray predicts the final vertebral collapse in elderly patients with thoracolumbar burst fracture. / La radiografía en bipedestación inmediata predice el colapso final de la vértebra fracturada en pacientes añosos con fractura estallido toracolumbar.

OBJECTIVE: To see if, in elderly patients with traumatic thoracolumbar fracture, standing X-rays with orthoses 24-48h after admission can predict vertebral collapse after consolidation. MATERIAL AND METHODS: Prospective cohort study endorsed by the Clinical Research Ethics Committee. INCLUSION CRITERIA: age >65 years, acute thoracolumbar junction fracture due to fall, hospital admission, treatment with orthesis. EXCLUSION CRITERIA: various levels, suspected malignancy, non-immediate fracture or atraumatic. VARIABLES: Farcy index (F), regional kyphosis (C: Cobb from cranial to caudal to broken vertebra) - both measured at admission (F0 and C0), at 24-48h in standing position with orthesis (F1 and C1) and 3 months, without brace (F2 and C2), collapse (increase from F0 to F1 -F0F1- and from F1 to F2 -F1F2-; as well as from C0 to C1 -C0C1- and from C1 to C2 -C1C2-), age and gender. STATISTICAL ANALYSIS: R package. RESULTS: Series of 40 patients, with a mean age of 75 years (66-87). Nine men and 31 women. Neither gender nor age were correlated with any variable. Six required surgery at follow-up. There were no differences in F1, C1, F0F1 or C0C1 between the six patients who required surgery and the other 34. Subsequently, data analysis was performed only for those patients who did not require surgery. The values obtained in the Farcy index were 8°+7° (F0), 12°+7° (F1) and 15°+8° (F2) and in kyphosis (three vertebrae, Cobb) they were: C0=8°+13°; C1=11.5°+14° and C2=13°+13°. There was a correlation of F2 with F0 and F1 (p<.001), with F0F1 (p=.038) and F1F2 (p=.007). The most powerful was with F1 (Rho Spearman=.889 (95% CI=.776-.947), with a Linear Regression line: F2=2.61288+F1×1.01237 (R2=.79). C2 was correlated with C0 and C1 (p<.001), especially with C1 (Rho Spearman=.952, 95% CI=.899-.977). Linear regression: C2=2.23371+C1×0.93758 (R2=.927). CONCLUSIONS: Immediate standing collapse predicts alignment at consolidation (3 months). It is therefore advisable to perform that radiography in the follow-up protocol.

[Bacteremia caused by Vibrio cholerae non-O1/non-O139 carrying a region homologous to pathogenicity island VpaI-7]. / Bacteriemia por Vibrio cholerae no-O1/no-O139 que porta una región homóloga a la isla de patogenicidad VpaI-7.

We report a case of V. cholerae non-O1 / non-O139 bacteremia in an 81-year-old woman with abdominal pain, fever, vomiting, liquid stools, choluria and jaundice, while visiting a rural area without access to potable water. The identification was made by the MALDI-TOF mass spectrometry technique and subsequently the non-toxigenic non-O1 / non-139 strain was confirmed in the national reference laboratory. The molecular characterization demonstrated the absence of the cholera toxin gene (CTX), and the TCP pilus, however, presented 5 of 6 virulence genes present in an island of homologous pathogenicity named VPaI-7 of V. parahaemolyticus (vcs N2 +, vcs C2 +, vcs V2 +, toxR-, vspD +, T vopF +) and in addition it was positive for hylAy rtxA virulence genes recognized outside the island. This is the first case reported in Chile of a clinical strain of V. cholerae non-O1, non-O139 isolated from blood culture that carries in its genome a homologous segment of the pathogenicity island named VPaI-7 of V. parahaemolyticus, which codifies for a type III secretion system (TTSS) that probably contributes to his virulence.

Bacteriemia por Vibrio cholerae no-O1/no-O139 que porta una región homóloga a la isla de patogenicidad VpaI-7 / Bacteremia caused by Vibrio cholerae non-O1/non-O139 carrying a region homologous to pathogenicity island VpaI-7

Resumen Presentamos un caso de bacteriemia por Vibrio cholerae no-O1/ no-O139 en una mujer de 81 años con un cuadro de dolor abdominal, fiebre, vómitos, diarrea, coluria e ictericia, mientras visitaba una zona rural sin acceso a agua potable. La identificación se realizó por la técnica de espectrometría de masa MALDI-TOF, confirmándose una cepa no toxigénica no-O1/no-139. La caracterización molecular del aislado demostró la ausencia del gen de la toxina del cólera (CTX), y pilus TCP; sin embargo, presentó cinco de los seis genes de virulencia presentes en la isla de patogenicidad homóloga denominada VPaI-7 del V. parahaemolyticus (vcs N2+, vcs C2+, vcs V2+,toxR-, vspD+, T vopF+). Además, el aislado presentó los genes de virulencia hylA y rtxA. Este es el primer caso reportado en Chile de una cepa clínica de V. cholerae no-O1, no-O139 aislada de hemocultivos portador de un segmento homólogo de la isla de patogenicidad denominada VPaI-7 de V. parahaemolyticus, el cual codifica para un sistema de secreción tipo III (TTSS), que probablemente contribuye a su virulencia.

We report a case of V. cholerae non-O1 / non-O139 bacteremia in an 81-year-old woman with abdominal pain, fever, vomiting, liquid stools, choluria and jaundice, while visiting a rural area without access to potable water. The identification was made by the MALDI-TOF mass spectrometry technique and subsequently the non-toxigenic non-O1 / non-139 strain was confirmed in the national reference laboratory. The molecular characterization demonstrated the absence of the cholera toxin gene (CTX), and the TCP pilus, however, presented 5 of 6 virulence genes present in an island of homologous pathogenicity named VPaI-7 of V. parahaemolyticus (vcs N2 +, vcs C2 +, vcs V2 +, toxR-, vspD +, T vopF +) and in addition it was positive for hylAy rtxA virulence genes recognized outside the island. This is the first case reported in Chile of a clinical strain of V. cholerae non-O1, non-O139 isolated from blood culture that carries in its genome a homologous segment of the pathogenicity island named VPaI-7 of V. parahaemolyticus, which codifies for a type III secretion system (TTSS) that probably contributes to his virulence.

Los problemas auditivos aumentan el riesgo de deterioro cognitivo en adultos mayores chilenos / Hearing impairments increase the risk of cognitive impairment in older Chilean adults

RESUMEN Introducción: Estudios previos han asociado la pérdida auditiva con un acelerado deterioro cognitivo durante el envejecimiento; no obstante, esta asociación no ha sido estudiada en adultos mayores chilenos. Objetivo: Investigar la asociación entre la discapacidad auditiva y la sospecha de deterioro cognitivo a través del cuestionario Mini Mental State Examination (MMSE, versión abreviada) en esta población. Material y método: Se incluyeron 1.384 adultos mayores de 60 años de la encuesta nacional de salud 2009-2010. Un puntaje <13 puntos en el MMSE se consideró sospecha de deterioro cognitivo. La discapacidad auditiva se determinó a través de un cuestionario de tamizaje autorreportado de tres preguntas. La asociación entre estas dos variables se investigó mediante análisis de regresión logística. Resultados: Se identificó una asociación significativa entre el MMSE alterado y cada una de las discapacidades auditivas estudiadas. A su vez, existió una tendencia a aumentar en 59% la probabilidad de desarrollar deterioro cognitivo en la medida que aumentaron las discapacidades auditivas (OR: 1,59 [95% IC: 1,38 a 1,82], p <0,0001). Conclusión: La disminución de la percepción auditiva es un factor de riesgo para el desarrollo de deterioro cognitivo y posteriormente demencia. La creación de políticas públicas, orientadas al tamizaje temprano en población de riesgo, podría ser una solución efectiva para prevenir las consecuencias asociadas con esta condición.

ABSTRACT Introduction: Hearing loss has been associated with an accelerated cognitive impairment during ageing. However, this association has not been investigated in older Chilean adults. Aim: To investigate the association between hearing impairment and cognitive impairment, using the Mini-Mental State Examination (MMSE, abridged version), in the Chilean population. Material and methods: 1,384 older adults aged ≥60 years, from 2009-2010 Chilean national health survey, were included. <13 points in the MMSE were considered suspicion of cognitive impairment. Hearing impairment was determined through a questionnaire including 3 domains. The association between cognitive and hearing loss was investigated using logistic regression. Results: An association between MMSE and each hearing disabilities studied was identified. As hearing impairments increased, the odd for cognitive impairment incremented by 59% (OR: 1.59 [95% IC: 1.38 a 1.82], p <0.0001). Conclusion: Hearing loss is a risk factor to develop cognitive impairment, which could translate into a high risk of dementia. Public politics implementation, focused in an early screening, could be an effective approach to prevent the complications associated with this hearing loss in older adults.

Mating and social exposure induces an opioid-dependent conditioned place preference in male but not in female prairie voles (Microtus ochrogaster).

In rodents, sexual stimulation induces a positive affective state that is evaluated by the conditioned place preference (CPP) test. Opioids are released during sexual behavior and modulate the rewarding properties of this behavior. Prairie voles (Microtus ochrogaster) are a socially monogamous species, in which copulation with cohabitation for 6h induces a pair bond. However, the mating-induced reward state that could contribute to the establishment of the long-term pair bond has not been evaluated in this species. The present study aimed to determine whether one ejaculation or cohabitation with mating for 6h is rewarding for voles. We also evaluated whether this state is opioid dependent. Our results demonstrate that mating with one ejaculation and social cohabitation with mating for 6h induce a CPP in males, while exposure to a sexually receptive female without mating did not induce CPP. In the female vole, mating until one ejaculation, social cohabitation with mating, or exposure to a male without physical interaction for 6h did not induce CPP. To evaluate whether the rewarding state in males is opioid dependent, the antagonist naloxone was injected i.p. The administration of naloxone blocked the rewarding state induced by one ejaculation and by social cohabitation with mating. Our results demonstrate that in the prairie vole, on the basis of the CPP in the testing conditions used here, the stimulation received with one ejaculation and the mating conditions that lead to pair bonding formation may be rewarding for males, and this reward state is opioid dependent.

Physiological and ultrastructural characterisation of a desiccation-tolerant filmy fern, Hymenophyllum caudiculatum: Influence of translational regulation and ABA on recovery.

The filmy fern Hymenophyllum caudiculatum can lose 60% of its relative water content, remain dry for some time and recover 88% of photochemical efficiency after 30 min of rehydration. Little is known about the protective strategies and regulation of the cellular rehydration process in this filmy fern species. The aim of this study was to characterise the filmy fern ultrastructure during a desiccation-rehydration cycle, and measure the physiological effects of transcription/translation inhibitors and ABA during desiccation recovery. Confocal and transmission electron microscopy were used to compare changes in structure during fast or slow desiccation. Transcription (actinomycin D) and translation (cycloheximide) inhibitors and ABA were used to compare photochemical efficiency during desiccation recovery. Cell structure was conserved during slow desiccation and rehydration, constitutive properties of the cell wall, allowing invagination and folding of the membranes and an important change in chloroplast size. The use of a translational inhibitor impeded recovery of photochemical efficiency during the first 80 min of rehydration, but the transcriptional inhibitor had no effect. Exogenous ABA delayed photochemical inactivation, and endogenous ABA levels decreased during desiccation and rehydration. Frond curling and chloroplast movements are possible strategies to avoid photodamage. Constitutive membrane plasticity and rapid cellular repair can be adaptations evolved to tolerate a rapid recovery during rehydration. Further research is required to explore the importance of existing mRNAs during the first minutes of recovery, and ABA function during desiccation of H. caudiculatum.

Proximal sacral deformity: a common element in lytic isthmic spondylolisthesis at L5 and in degenerative spondylolisthesis at L4-L5 segment. Two apparently very different etiopathogenic entities. / Deformidad sacra proximal: elemento común a la espondilolistesis ístmica lítica de L5 y a la degenerativa del segmento L4-L5, 2 entidades de etiopatogenia muy diferente, aparentemente.

A radiographic study was carried out to investigate the relationship between proximal sacral sagittal anatomy (either kyphosis or lordosis) and either isthmic or degenerative spondylolisthesis. In addition, we studied whether there is a relationship between proximal sacral kyphosis and the degree of such listhesis in the case of L5 isthmic spondylolisthesis. Lateral standing x-rays were used from 173 patients, ninety of whom had degenerative spondylolisthesis L4-L5, and eighty-three an isthmic spondylolisthesis of L5 (67 low-grade and 16 high-grade) and compared with a control group of 100 patients adjusted by age and gender, without any type of spondylolisthesis. Listhesis was graded using Meyerding's classification and the proximal sacral kyphosis angle (CSP) was measured between S1 and S2 posterior walls, according to Harrison's method. In our series, there was a proximal sacral kyphosis in both types of spondylolisthesis, greater in the lytic type. By contrast, the control group had a proximal sacral lordosis. The differences were statistically significant. Therefore, we concluded that there was a proximal sacral kyphosis in patients with both degenerative and isthmic lytic spondylolisthesis, but with our results, we were not able to ascertain whether it is a cause or a consequence of this listhesis.

Lordosis manoeuvre in the diagnosis of lumbar facet syndrome. / Efectividad de la maniobra lordosante en el diagnóstico del síndrome facetario lumbar.

UNLABELLED: In lumbar pain patients an aetiopathogenic diagnosis leads to a better management. When there are alarm signs, they should be classified on an anatomical basis through anamnesis and physical examination. A significant group is of facet origin (lumbar facet syndrome [LFS]), but the precise clinical diagnosis remains cumbersome and time-consuming. In clinical practice it is observed that patients with an advanced degenerative disease do not perform extension or rotation of their lumbar spine when prompted to extend it, but rather knee flexion, making the manoeuvre meaningless. For this reason, a new simple and quick clinical test was developed for the diagnosis of lumbar facet syndrome, with a facet block-test as a confirmation. HYPOTHESIS: The new test is better than a classic one in the diagnosis of facet syndrome, and probably even better than imaging studies MATERIALS AND METHODS: A prospective study was conducted on a series of 68 patients (01/01/2012-30/06/2013). A comparison in between: classic manoeuvre (CM), imaging diagnostics (ID), and the new lordosis manoeuvre (LM) test. Examination and block test by one author, and evaluation of results by another one. EXCLUSION CRITERIA: Deformity and instability. using a physical. OBJECTIVE: To determine the effectiveness of a new clinical test (LM) for the diagnosis of LFS (as confirmed by a positive block-test of medial branch of dorsal ramus of the lumbar root, RMRDRL). STATISTICS: R package software. RESULTS: The LM was most effective (p<.0001; Kappa 0.524, p<.001). There was no correlation between either the CM or ID and the block-test results (Kappa, CM: 0.078; p=.487, and ID: 0.195; p=.105). There was a correlation between ID (CAT/MR) and LM (p=.024; Kappa 0.289 p=.014), although not with CM. There was no correlation between ID (plain X-rays) and CM or LM. CONCLUSIONS: A new test for diagnosis of LFS is presented that is reliable, quick, and simple. Clinical examination is more reliable than imaging test for the diagnosis of LFS.

Analysis of root-knot nematode and fusarium wilt disease resistance in cotton (Gossypium spp.) using chromosome substitution lines from two alien species.

Chromosome substitution (CS) lines in plants are a powerful genetic resource for analyzing the contribution of chromosome segments to phenotypic variance. In this study, a series of interspecific cotton (Gossypium spp.) CS lines were used to identify a new germplasm resource, and to validate chromosomal regions and favorable alleles associated with nematode or fungal disease resistance traits. The CS lines were developed in the G. hirsutum L. TM-1 background with chromosome or chromosome segment substitutions from G. barbadense L. Pima 3-79 or G. tomentosum. Root-knot nematode (Meloidogyne incognita) and fusarium wilt (Fusarium oxysporum f. sp. vasinfectum) (races 1 and 4) resistance alleles and quantitative trait loci (QTL) previously placed on cotton chromosomes using SSR markers in two interspecific recombinant inbred line populations were chosen for testing. Phenotypic responses of increased resistance or susceptibility in controlled inoculation and infested field assays confirmed the resistance QTLs, based on substitution with the positive or negative allele for resistance. Lines CS-B22Lo, CS-B04, and CS-B18 showed high resistance to nematode root-galling, confirming QTLs on chromosomes 4 and 22 (long arm) with resistance alleles from Pima 3-79. Line CS-B16 had less fusarium race 1-induced vascular root staining and higher percent survival than the TM-1 parent, confirming a major resistance QTL on chromosome 16. Lines CS-B(17-11) and CS-B17 had high fusarium race 4 vascular symptoms and low survival due to susceptible alleles introgressed from Pima 3-79, confirming the localization on chromosome 17 of an identified QTL with resistance alleles from TM1 and other resistant lines. Analyses validated regions on chromosomes 11, 16, and 17 harboring nematode and fusarium wilt resistance genes and demonstrated the value of CS lines as both a germplasm resource for breeding programs and as a powerful genetic analysis tool for determining QTL effects for disease resistance. CS lines carrying small alien chromosome segments with favorable QTL alleles could be used for effective introgression of biotic stress resistance or many other desirable traits by targeting gene interactions and reducing linkage drag effects.

Prognostic value of an immediate lateral standing X-ray with a TLSO in patients with a thoracolumbar burst fracture.

UNLABELLED: The final collapse of a "stable" thoracolumbar burst fracture is difficult to predict. This collapse was prospectively studied radiologically in patients with T12 or L1 burst fractures who, after evaluating the admission x-rays and the CT scan with the patients themselves, opted for a rigid thoracolumbar brace with support in the sternal manubrium (TLSO). On the other hand, patients with rigid braces sometimes have low back pain on follow-up (due to overload of the L5-S1 joints). HYPOTHESIS: the standing lateral x-ray with only a TLSO for support (intrinsic mechanical stability) provides information on the final collapse and could also provide information on the low back pain. The study included 50 patients (20 males and 30 females, age: 63+14 years) admitted during 2011 and 2012, with 2 losses to follow-up. VARIABLES: Farcy index and local kyphosis (Cobb at 3 vertebrae). X-Rays: admission, with TLSO (immediate: Rx0), and at 3 and 6 months. They were compared with the final clinical and radiological results. It was decided to surgically intervene in 4 patients after Rx0. There were no painful sequelae at the fracture level, and 16/44 (31%) had low back pain. Using linear regression mathematical models, the increase in the Farcy index (Rx0-Rx admission) was associated with the appearance of low back pain and with local kyphosis (Rx0-Rx admission), and with the final kyphosis. It is advisable to perform a lateral standing X-ray after TLSO for information on the final collapse of the fracture and the appearance of accompanying low back pain.

Making strides towards better mental health care in Peru: Results from a primary care mental health training.

Our program attempted to improve attitudes and confidence of Peruvian primary care physicians (PCPs) providing mental health care. The training program underwent an evaluation to determine impact of sustained confidence in performing medical and psychiatric procedures, and application of learned skills. Fifty-two Peruvian primary care practitioners were trained at the Harvard Program in Refugee Trauma (HPRT) over a two-week period. There was significant improvement in PCPs' confidence levels of performing psychiatric procedures (counseling, prescribing medications, psychiatric diagnosis, assessing the risk for violence, and treating trauma victims) when comparing baseline and post-two-week to one year follow-up. When comparing post-two-week and one-year follow-up quantitative measures, confidences levels went slightly down. This may be an implication that the frequency of trainings and supervisions are needed more frequently. In contrast, qualitative responses from the one-year follow-up revealed increase in victims of violence clinical care, advocacy, awareness, education, training, policy changes, accessibility of care, and sustainment of diagnostic tools. This study supports the feasibility of training PCP's in a culturally effective manner with sustainability over time.

Detección de serinocarbapenemasas de clase A y otros mecanismos de resistencia enzimática a β-lactámicos en cepas de enterobacterias con susceptibilidad disminuida a carbapenémicos, aisladas de pacientes de un hospital universitario de Santiago, Chile / Detection of serinocarbapenemases Class A and other mechanisms of enzymatic resistance to β-lactams in enterobacteria strains with diminished susceptibility to carbapenems isolated of patients in a university hospital

Background: The emergence of carbapenemase mediated resistance in Enterobacteriaceae has a strong clinical impact. This study aimed to do a genotypic and phenotypic characterization of the enzymatic resistance to β-lactams in clinical Enterobacteriaceae isolates with decreased susceptibility to carbapenems in a university medical center in Santiago. Methods: During April-September 2010 at Hospital Clinico Universidad de Chile, 23 isolates of carbapenem non susceptible Enterobacteriaceae were collected. We used PCR for the detection of class A carbapenemases (SME, IMI, NMC, GES and KPC) and the modified Hodge with the boronic acid test to phenotypically assess the presence of serine-carbapenemases. To assess extended spectrum β-lactamases (ESBLs) the CLSI phenotypic tests were performed. Metallo-β-lactamases (MBL) and AmpC were assessed with commercial tablets. Results: 18/23 were Klebsiellapneumoniae and 5/23 strains were Enterobacter cloacae. All PCR to class A carbapenemases were negative. 3/23 strains (all E. cloacae), were positive to the Hodge modified test and 1/23, a K.pneumoniae, was positive to the boronic acid test. ESBLs were detected in 14/23 os the strains and AmpC in 5/23. No MBL was detected. Conclusion: No class A serine-carbapenemasa was detected. The decreased susceptibility to carbapenems is probably explained by the β-lactamase activity and due to porin loss.

Introducción: La emergencia de resistencia a β-lactámicos por carbapenemasas en enterobacterias tiene gran importancia clínica. El objetivo de este estudio fue caracterizar genotípica y fenotípicamente la resistencia enzimática a β-lactámicos en enterobacterias con susceptibilidad disminuida a carbapenémicos, en cepas aisladas de pacientes de un hospital universitario de Santiago. Metodología: Durante abril-septiembre 2010, en el Hospital Clínico de la Universidad de Chile se recolectaron 23 aislados. Se detectaron serinocarbapenemasas clase A (SME, IMI, NMC, GES y KPC) mediante RPC. Se empleó el test de Hodge modificado y acido fenil-borónico (APB) para la detección fenotípica de serinocarbapenemasas. Se detectó la presencia de β-lactamasas de espectro extendido según CLSI y AmpC y MBL mediante tabletas comerciales. Resultados: 18 cepas (78,26%) correspondieron a Klebsiella pneumoniae y 5 cepas (21,74%) a Enterobacter cloacae. Todas las RPC para serinocarbapenemasas fueron negativas, en tanto, el test de Hodge fue positivo para 3/23 cepas, todas E. cloacae. Una cepa de K. pneumoniae fue positiva para APB. Se detectó BLEE en 14/23 cepas, AmpC en 5/23 cepas y no se detectó MBL. Conclusiones: En las cepas estudiadas no se detectaron serinocarbapenemasas clase A. Probablemente los mecanismos que explican la susceptibilidad disminuida a carbapenémicos, involucran resistencia enzimática, combinados con cambios en la permeabilidad de la membrana bacteriana.

[Occipital-cervical instability in Morquio disease: a presentation of 2 cases and a review of the literature]. / Inestabilidad occipitocervical en la enfermedad de Morquio. Presentación de 2 casos y revisión de la literatura.

INTRODUCTION: Morquio syndrome is caused by an inherited autosomal recessive enzyme deficiency. It presents with numerous musculoskeletal anomalies, among which atlantoaxial instability is highlighted, due it being life-threatening. Occipital-cervical arthrodesis surgery (and decompression) is indicated in these cases. OBJECTIVE: The cases of 2 patients with Morquio syndrome that required this type of surgery are presented, along with a review of the literature. PATIENTS AND METHODS: Two patients: one boy and one girl, with Morquio syndrome and high cervical instability, with neurological signs and symptoms, who were subjected to surgery using decompression and instrumented occipital-cervical arthrodesis and followed up for 6 months and one year, respectively. RESULTS: The neurological problems of both patients improved, and are currently having a normal life for their age. CONCLUSION: Occipital-cervical arthrodesis with decompression provides a safe biomechanical environment that prevents neurological involvement. It should be indicated before the appearance of symptoms or mechanical instability.

[Detection of serinocarbapenemases Class A and other mechanisms of enzymatic resistance to ß-lactams in enterobacteria strains with diminished susceptibility to carbapenems isolated of patients in a university hospital]. / Detección de serinocarbapenemasas de clase A y otros mecanismos de resistencia enzimática a ß-lactámicos en cepas de enterobacterias con susceptibilidad disminuida a carbapenémicos, aisladas de pacientes de un hospital universitario de Santiago, Chile.

BACKGROUND: The emergence of carbapenemase mediated resistance in Enterobacteriaceae has a strong clinical impact. This study aimed to do a genotypic and phenotypic characterization of the enzymatic resistance to ß-lactams in clinical Enterobacteriaceae isolates with decreased susceptibility to carbapenems in a university medical center in Santiago. METHODS: During April-September 2010 at Hospital Clinico Universidad de Chile, 23 isolates of carbapenem non susceptible Enterobacteriaceae were collected. We used PCR for the detection of class A carbapenemases (SME, IMI, NMC, GES and KPC) and the modified Hodge with the boronic acid test to phenotypically assess the presence of serine-carbapenemases. To assess extended spectrum ß-lactamases (ESBLs) the CLSI phenotypic tests were performed. Metallo-ß-lactamases (MBL) and AmpC were assessed with commercial tablets. RESULTS: 18/23 were Klebsiellapneumoniae and 5/23 strains were Enterobacter cloacae. All PCR to class A carbapenemases were negative. 3/23 strains (all E. cloacae), were positive to the Hodge modified test and 1/23, a K.pneumoniae, was positive to the boronic acid test. ESBLs were detected in 14/23 os the strains and AmpC in 5/23. No MBL was detected. CONCLUSION: No class A serine-carbapenemasa was detected. The decreased susceptibility to carbapenems is probably explained by the ß-lactamase activity and due to porin loss.

Patrones de susceptibilidad antimicrobiana de cepas de Shigella sonnei aisladas durante tres períodos diferentes en la Región Metropolitana, Chile / Antibiotic susceptibility patterns among Shigella sonnei, isolated during three different periods in Región Metropolitana, Chile

Background: Shigella sonnei gastroenteritis improves clinically and microbiologically with antibacterial treatment; however choosing a useful drug is a universal challenge because of in vitro susceptibility of S. sonnei frequently evolves to be resistant. Objective: To evaluate in vitro susceptibility of S. sonnei strains isolated from patients attending at the Chilean Región Metropolitana and to know the evolution that resistant patterns of S. sonnei have experienced. Material: In this study, the antimicrobial susceptibility profile of 277 isolates of Shigella sonnei was compared. The analyzed periods of time were: period I (1995-1997) 85 strains; period II (2004-2006) 92 strains and period III (2008-2009) 100 strains, in Santiago, Chile. The method performed to analyze susceptibility patterns was the disc diffusion (Kirby-Bauer). Results: The strains showed rates of resistance to ampicillin: period I, 85.8%; period II, 53.3%; period III, 100%, trimethoprim/sulfamethoxazole: period I, 50.5%; period, II 46.7%; period III, 100%, chloramphenicol: period I, 36.4%; period II, 12%; period III, 100% and tetracycline: period I, 38.8%; period II, 30.4%; period III, 100%. 98.9% of the strains showed susceptibility to quinolones. Significant differences were observed in patterns of antimicrobial resistance for both individuals and for multidrug resistance (≥ 3 antimicrobials) in the three periods (p < 0.001, χ2 test). Of all resistant strains, 17% were resistant to 1 or 2 antibiotics, while 65.7% showed a pattern of multidrug resistance; 100% of the period III strains presented multidrug resistance. Conclusion: These results showed the temporal resistance dynamics of S. sonnei circulating strains in the Chilean Región Metropolitana. Due to the endemic behavior of shigellosis in Chile, it is urgent to maintain permanent surveillance of antimicrobial resistance profiles to improve both prevention and treatment of shigellosis.

Introducción: La infección entérica producida por Shigella sonnei mejora clínicamente y microbiológicamente con antibioterapia; sin embargo, la elección del antimicrobiano es un problema universal pues la susceptibilidad in vitro de S. sonnei evoluciona frecuentemente hacia la resistencia. Objetivo: Evaluar la susceptibilidad in vitro a antimicrobianos de S. sonnei y conocer la evolución que han experimentado los patrones de resistencia de cepas aisladas de cuadros clínicos en pacientes de la Región Metropolitana, Chile. Material y Métodos: Se comparó el perfil de susceptibilidad a antimicrobianos, de 277 cepas clínicas de S. sonnei aisladas durante tres períodos: período I (1995-1997) 85 cepas; período II (2004-2006) 92 cepas y período III (2008-2009) 100 cepas, en Santiago, Chile. El perfil de susceptibilidad a antimicrobianos se determinó mediante test de difusión en agar. Resultados: Las tasas de resistencia de las cepas en los periodos I, II y III respectivamente fueron: ampicilina: 85,8%; 53,3%; 100%, cotrimoxazol: 50,5%; 46,7%; 100%, cloranfenicol: 36,4%; 12%; 100% y tetraciclina: 38,8%; 30,4%; 100%. El 98,9% de las cepas fue susceptible a quinolonas. Se observó diferencias significativas en los porcentajes de resistencia para antimicrobianos individuales y multi-resistencia (≥ 3 antimicrobianos) en los tres períodos (p < 0,001; Test de χ2). De las cepas resistentes, 17% presentó resistencia a uno ó dos antimicrobianos, 65,7% mostró multi-resistencia antimicrobiana. El 100% de las cepas del período III presentó multi-resistencia. Discusión: Estos resultados evidencian la dinámica temporal de la resistencia en cepas de S. sonnei circulantes en la Región Metropolitana. Dado que en Chile la shigelosis tiene un carácter endémico, es prioritario mantener una vigilancia constante de los perfiles de resistencia a antimicrobianos, para mejorar la prevención y el tratamiento de la shigelosis.

[Inveterate subaxial cervical dislocations: a discussion on the best therapeutic strategy]. / Luxación subaxial cervical inveterada. Discusión de cuál es la mejor estrategia terapéutica.

It is difficult to decide the appropriate treatment for inveterate cervical dislocations because of the difficulty of their reduction, as well as due to the risk of inducing iatrogenic injuries during this reduction. The literature on the most appropriate surgical strategy for their management is also limited as well as controversial. We report one clinical case treated in the Spine Unit of the Orthopedic Surgery and Trauma Service of the University Hospital of Santiago de Compostela, discussing the currently most used treatment options, the anterior-posterior-anterior and the posterior-anterior-posterior approach. After analyzing the results, it could be concluded that the surgical approach to these lesions is generally difficult, with any of two techniques described above being suitable, but always with the precaution to remove the entire affected intervertebral disc before axial correction maneuvers, thus avoiding the risk of extrusion into the medullary canal. After the surgical procedure, a proper release and reduction of the joint facets should be performed, sometimes with the need to add osteotomies in them.

Co-infection patterns of infectious salmon anaemia and sea lice in farmed Atlantic salmon, Salmo salar L., in southern Chile (2007-2009).

Infectious salmon anaemia virus (ISAV) caused a large epidemic in farmed Atlantic salmon in Chile in 2007-2009. Here, we assessed co-infection patterns of ISAV and sea lice (SL) based on surveillance data collected by the fish health authority. ISAV status and SL counts in all Atlantic salmon farms located in the 10th region of Chile were registered monthly from July 2007 through December 2009. Each farm was categorized monthly according to its ISAV and SL status. A multinomial time-space scan test using a circular window was applied to identify disease clusters, and a multivariate regression model was fitted to quantify the association between disease-clustering and farm-management factors. Most of the identified clusters (9/13) were associated with high SL burdens. There were significant associations (P < 0.05) between management factors and ISAV/SL status. Areas in which good management practices were associated with a reduced disease risk were identified. The findings of this study suggest that certain management practices can effectively reduce the risk of SL and ISAV in the face of an epidemic and will be helpful towards creating an effective disease control programme in Chile.

[Antibiotic susceptibility patterns among Shigella sonnei, isolated during three different periods in Región Metropolitana, Chile]. / Patrones de susceptibilidad antimicrobiana de cepas de Shigella sonnei aisladas durante tres períodos diferentes en la Región Metropolitana, Chile.

BACKGROUND: Shigella sonnei gastroenteritis improves clinically and microbiologically with antibacterial treatment; however choosing a useful drug is a universal challenge because of in vitro susceptibility of S. sonnei frequently evolves to be resistant. OBJECTIVE: To evaluate in vitro susceptibility of S. sonnei strains isolated from patients attending at the Chilean Región Metropolitana and to know the evolution that resistant patterns of S. sonnei have experienced. MATERIAL: In this study, the antimicrobial susceptibility profile of 277 isolates of Shigella sonnei was compared. The analyzed periods of time were: period I (1995-1997) 85 strains; period II (2004-2006) 92 strains and period III (2008-2009) 100 strains, in Santiago, Chile. The method performed to analyze susceptibility patterns was the disc diffusion (Kirby-Bauer). RESULTS: The strains showed rates of resistance to ampicillin: period I, 85.8%; period II, 53.3%; period III, 100%, trimethoprim/sulfamethoxazole: period I, 50.5%; period, II 46.7%; period III, 100%, chloramphenicol: period I, 36.4%; period II, 12%; period III, 100% and tetracycline: period I, 38.8%; period II, 30.4%; period III, 100%. 98.9% of the strains showed susceptibility to quinolones. Significant differences were observed in patterns of antimicrobial resistance for both individuals and for multidrug resistance (≥ 3 antimicrobials) in the three periods (p < 0.001, χ2 test). Of all resistant strains, 17% were resistant to 1 or 2 antibiotics, while 65.7% showed a pattern of multidrug resistance; 100% of the period III strains presented multidrug resistance. CONCLUSION: These results showed the temporal resistance dynamics of S. sonnei circulating strains in the Chilean Región Metropolitana. Due to the endemic behavior of shigellosis in Chile, it is urgent to maintain permanent surveillance of antimicrobial resistance profiles to improve both prevention and treatment of shigellosis.