Caracterización de lactantes con infección del tracto urinario:2009-2010: Hospital Regional de Antofagasta / Characterization of infants with urinary tract infection: 2009-2010: Regional Hospital of Antofagasta

INTRODUCCION: Las infecciones del tracto urinario (ITU) son una de las enfermedades bacterianas más frecuentes en pediatría. La incidencia de ITU en el paciente pediátrico no se conoce con exactitud. En recién nacidos se estima en 1 por ciento con una mayor proporción de varones, mientras que en lactantes aumenta entre 3 a 5 por ciento con igual proporción en ambos sexos. OBJETIVO: Caracterizar el perfil clínico-epidemiológico de lactantes con diagnóstico de ITU en el servicio de Pediatría del Hospital Regional de Antofagasta. PACIENTES Y METODOS: Estudio descriptivo retrospectivo de corte transversal. Se analizaron fichas clínicas de pacientes de la unidad de lactantes del Servicio de Pediatría del Hospital Regional de Antofagasta con diagnóstico de ITU al egreso del periodo Mayo 2009 - Mayo 2010. La muestra final fue 88 pacientes. Los datos fueron analizados y tabulados en una planilla Excel2007. RESULTADOS: Un 71,5 por ciento fueron sexo femenino. La edad promedio fue de 8,9 meses con rango entre 1 mes y 23 meses. Los síntomas más frecuentes fueron fiebre (97,7 por ciento), vómitos (30,7 por ciento), diarrea (23,1 por ciento), inapetencia (21.6 por ciento) y llanto/irritabilidad (16 por ciento). Las alteraciones de laboratorio fueron PCR elevada (96 por ciento), piuria (94,3 por ciento), leucocitosis (87,5 por ciento) y nitritos positivos (48 por ciento). Sólo fueron consignados el 85,2 por ciento de los urocultivos, de los cuales el patógeno más frecuente fue Escherichia coli en el 84 por ciento. DISCUSION: La ITU en lactantes en nuestro estudio fue más frecuente en el sexo femenino, teniendo como signo preponderante la fiebre. El germen más común fue Escherichia coli, correlacionándose con la literatura. Valoramos la importancia de solicitar urocultivos para la confirmación microbiológica.

INTRODUCTION: Urinary tract infections (UTI) are one of the most frequent bacterial diseases in pediatrics. The incidence of UTI in pediatric patients is not known with accuracy. In newborns is estimated in 1 percent with a larger proportion in males, while in infants increase between 3 to 5 percent with the same proportion for both sex. OBJECTIVE: Characterize clinically and epidemiologically the profile of infants diagnosed with UTI in the Pediatric service of the Regional Hospital of Antofagasta. METHODS AND MATERIALS: A descriptive retrospective cross-sectional study. Medical records of patients diagnosed with UTI by the end of the period of May 2009 - May 2010 from the unit of infants in the Pediatric Service of the Regional Hospital of Antofagasta were analyzed. The final sample was 88 patients. The data was analyzed using an Excel 2007 spreadsheet. RESULTS: 71,5 percent were women. The average age was 8,9 month in a range between 0,5 and 23 month. Most frequent symptoms were fever (97,7 percent), vomit (30,7 percent), diarrhea (23,1 percent), lack of appetite (21,6 percent) and crying/irritability (16 percent). The alterations in laboratory was CRP high (96 percent), pyuria (94,3 percent) and leukocytosis (87,5 percent). Only were record the 85, 2 percent of urine culture of which the most frequent pathogenic agent was Escherichia coli in the 84 percent of the cases. DISCUSSION: The UTI in infants in our study was more frequent in women and its predominant symptom is fever. The most common germ was Escherichia coli which agree the literature. We value the importance of ask for urine culture to microbiological confirmation.

Resultados funcionales y determinación de la osteointegración, en pacientes con prótesis total de cadera no cementada: durante el período de enero 2000 a diciembre 2006 / Functional results and determination of osseointegration in patients with total hip prosthesis is not cemented: during the period january 2000 to december 2006

Evaluar los resultados finales y estudios radiológicos como la radiografía convencional y densitometría ósea (DEXA), determinar las complicaciones, principalmente aflojamiento aséptico, infecciones, fracturas peri protésicas, desmineralización ósea de las Prótesis Totales de Cadera no Cementadas (PTCNC). Modelo del tipo serie clínica con un tamaño de la muestra de 148 caderas estudiadas. Se obtuvieron un 72,3 por ciento de resultados clínicos satisfactorios con la escala de Harris (HSS), así como un 51,4 por ciento de resultados radiológicos no satisfactorios que no guardan relación con los resultados funcionales; sólo un 2,7 por ciento de infección protésica; la Densidad Mineral Ósea (DMO) por densitometría a doble foton (DEXA) alrededor del vástago fue menor del 50 por ciento y las zonas de Gruen afectadas con más frecuencia son las IV y VII. La artroplastia total de la cadera no cementada es el tratamiento de elección primaria para los casos de artrosis severa que limita la función articular. La escala de Harris (HHS) y las zonas de Gruen medidas por DEXA, nos demostró ser eficaz para determinar los aflojamientos y tener una idea de cual puede ser la longevidad del implante protésico.

Efficacy and safety of short-term adalimumab treatment in patients with active Crohn's disease who lost response or showed intolerance to infliximab: a prospective, open-label, multicentre trial.

BACKGROUND: The use of tumour necrosis factor antagonists has changed the therapeutic approach to Crohn's disease. AIM: To determine response and remission rates associated with the 4-week induction phase of adalimumab treatment in patients with luminal and/or fistulizing Crohn's disease, who have lost response to or become intolerant of infliximab. METHODS: In this multicentre, prospective, open-label, observational, 52-week study, 50 adults received an induction dose of adalimumab (160 mg at baseline followed by 80 mg at week 2). RESULTS: Of the 36 patients with luminal Crohn's disease, 83% achieved clinical response [> or =70-point reduction in the Crohn's Disease Activity Index (CDAI) score] and 42% achieved clinical remission (CDAI score <150) at week 4. Of the 22 patients with fistulizing disease, five (23%) experienced fistula remission (complete closure of all fistulas that were draining at baseline), and nine (41%) experienced fistula improvement (> or =50% decrease in the number of fistulas that were draining at baseline) at week 4. Of the 19 adverse events, most [13 (68%)] were mild, and no serious or infectious adverse events occurred. CONCLUSIONS: Adalimumab may be an effective alternative in patients with luminal and/or fistulizing Crohn's disease who have lost response to or become intolerant of infliximab.

Role of metallothioneins in peripheral nerve function and regeneration.

The physiological role of the metallothionein (MT) family of proteins during peripheral nerve injury and regeneration was examined in Mt1+ 2 and Mt3 knockout (KO) mice. To this end, the right sciatic nerve was crushed, and the regeneration distance was evaluated by the pinch test 2-7 days postlesion (dpl) and electrophysiologically at 14 dpl. The quality of the regeneration was assessed by light microscopy and immunohistochemical methods. The results show that the regeneration distance was greater in the Mt3 KO than in the Mt1+ 2 KO mice, whereas control mice showed intermediate values. Moreover, the number of regenerating axons in the distal tibial nerve was significantly higher in Mt3KO mice than in the other two strains at 14 dpl. Immunoreactive profiles to protein gene product 9.5 were present in the epidermis and the sweat glands of the plantar skin of the hindpaw of the Mt3 KO group. The improved regeneration observed with the Mt3 KO mice was confirmed by compound nerve action potentials that were recorded from digital nerves at 14 dpl only in this group. We conclude that Mt3 normally inhibits peripheral nerve regeneration.

Engineering an artificial nerve graft for the repair of severe nerve injuries.

Nerve repair with tubes has a limit to regeneration depending upon the length of the gap. The characteristics of the guide, in terms of permeability, durability and adhesiveness, also influence regeneration. Considering the importance of the cellular component in regeneration, the development of artificial grafts, composed of a biocompatible nerve guide filled with a neurotropic matrix and seeded with Schwann cells (SCs), is an interesting option to enhance nerve regeneration and provide an alternative to the classical autologous nerve graft. We evaluated the ability of SCs transplanted into a nerve guide to improve regeneration after sciatic nerve resection, leaving a 6-mm gap, in the mouse. Syngeneic, isogeneic and autologous SCs were suspended in Matrigel and seeded in resorbable guides, and compared to acellular guides and to nerve autografts. The immunogenicity of the transplanted SCs clearly influenced the outcome. Transplants of autologous SCs resulted in only slightly lower levels of reinnervation than autografts, but higher recovery and number of regenerated axons than transplants of isologous and syngeneic SCs, and than acellular guides. Thus, by combined developments on nerve guides, extracellular matrix components and cell transplantation, an artificial graft has been designed that allows axonal regeneration across long gaps to levels comparable with an autograft.

Effects of FK506 on nerve regeneration and reinnervation after graft or tube repair of long nerve gaps.

We compared the effects of FK506 administration on regeneration and reinnervation after sciatic nerve resection and repair with an autologous graft or with a silicone tube leaving a 6-mm gap in the mouse. Functional reinnervation was assessed by noninvasive methods to determine recovery of motor, sensory, and sweating functions in the hindpaw over 4 months after operation. Morphometric analysis of the regenerated nerves was performed at the end of follow-up. The nerve graft allowed for faster and higher levels of reinnervation in the four functions tested than silicone tube repair. Treatment with FK506 (for the first 9 weeks only) resulted in a slight, although not significant, improvement of the onset of reinnervation and of the maximal degree of recovery achieved after autografting. The recovery of pain sensibility and of the compound nerve action potentials in the digital nerves, which directly depend on axonal regeneration, showed better progression with FK506 than reinnervation of muscles and sweat glands, which require reestablishment of synaptic contacts with target cells. The myelinated fibers in the regenerated nerve showed a more mature appearance in the FK506-treated rats. However, FK506 showed a marginal effect in situations in which regeneration was limited, as in a silicone tube bridging a 6-mm gap in the mouse sciatic nerve. In conclusion, treatment with FK506 improved the rate of functional recovery after nerve resection and autograft repair.

Polyimide cuff electrodes for peripheral nerve stimulation.

This paper describes a new tripolar spiral cuff electrode, composed of a thin (10 microm) and flexible polyimide insulating carrier and three circumneural platinum electrodes, suitable for stimulation of peripheral nerves. The cuffs were implanted around the sciatic nerve of two groups of ten rats each, one in which the polyimide ribbon was attached to a plastic connector to characterize the in vivo stimulating properties of the electrode, and one without a connector for testing possible mechanical nerve damage by means of functional and histological methods. The polyimide cuff electrodes induced only a very mild foreign body reaction and did not change the nerve shape over a 2-6 month implantation period. There were no changes in the motor and sensory nerve conduction tests, nociceptive responses and walking track pattern over follow-up, and no morphological evidence of axonal loss or demyelination, except in one case with partial demyelination of some large fibers after 6 months. By delivering single electrical pulses through the cuff electrodes graded recruitment curves of alpha-motor nerve fibers were obtained. Recruitment of all motor units was achieved with a mean charge density lower than 4 microC/cm(2) for a pulse width of 50 micros at the time of implantation as well as 45 days thereafter. These data indicate that the polyimide cuff electrode is a stable stimulating device, with physical properties and dimensions that avoid nerve compression or activity-induced axonal damage.

Nerve guides seeded with autologous schwann cells improve nerve regeneration.

This study evaluates the ability of Schwann cells (SCs) transplanted into a nerve guide to improve regeneration and reinnervation after sciatic nerve resection and repair, leaving a 6-mm gap, in the mouse. SCs were isolated from predegenerated adult sciatic nerves and expanded in culture using a chemically defined medium. Syngeneic, isogeneic, and autologous SCs were suspended in Matrigel and seeded in resorbable, permeable poly(l-lactide-co-epsilon-caprolactone) guides at 150,000 cells/tube. Guides containing SCs were compared to guides filled with Matrigel alone and with peroneal nerve autografts. Functional reinnervation was assessed by noninvasive methods to determine recovery of sweating, nociceptive, sensory, and motor functions in the hindpaw during 4 months postoperation. Morphological analysis of the regenerated nerves was performed at the end of follow-up. The group with an autograft achieved faster and higher levels of reinnervation and higher number of regenerated myelinated fibers than groups repaired by tubulization. The immunogenicity of transplanted SCs influenced the outcome of nerve regeneration. Transplants of autologous SCs resulted in slightly lower levels of reinnervation than autografts, but higher recovery and number of regenerated fibers reaching the distal nerve than transplants of isologous and syngeneic SCs, although most of the differences were not statistically significant. Syngeneic SCs did not improve regeneration with respect to acellular guides. Prelabeled transplanted SCs were found to survive into the guide 1-3 months after implantation, to a larger number when they were autologous than syngeneic. Cellular prostheses composed of a resorbable guide seeded with autologous SCs appear as an alternative for repairing long gaps in injured nerves, approaching the success of autografts.

Influence of aging on peripheral nerve function and regeneration.

Aging deeply influences several morphologic and functional features of the peripheral nervous system (PNS). Morphologic studies have reported a loss of myelinated and unmyelinated nerve fibers in elderly subjects, and several abnormalities involving myelinated fibers, such as demyelination, remyelination and myelin balloon figures. The deterioration of myelin sheaths during aging may be due to a decrease in the expression of the major myelin proteins (P0, PMP22, MBP). Axonal atrophy, frequently seen in aged nerves, may be explained by a reduction in the expression and axonal transport of cytoskeletal proteins in the peripheral nerve. Aging also affects functional and electrophysiologic properties of the PNS, including a decline in nerve conduction velocity, muscle strength, sensory discrimination, autonomic responses, and endoneurial blood flow. The age-related decline in nerve regeneration after injury may be attributed to changes in neuronal, axonal, Schwann cell and macrophage responses. After injury, Wallerian degeneration is delayed in aged animals, with myelin remnants accumulated in the macrophages being larger than in young animals. The interaction between Schwann cells and regenerative axons takes longer, and the amount of trophic and tropic factors secreted by reactive Schwann cells and target organs are lower in older subjects than they are in younger subjects. The rate of axonal regeneration becomes slower and the density of regenerating axons decrease in aged animals. Aging also determines a reduction in terminal and collateral sprouting of regenerated fibers, further limiting the capabilities for target reinnervation and functional restitution. These age-related changes are not linearly progressive with age; the capabilities for axonal regeneration and reinnervation are maintained throughout life, but tend to be delayed and less effective with aging.

Magnetically aligned collagen gel filling a collagen nerve guide improves peripheral nerve regeneration.

Bioresorbable collagen nerve guides filled with either magnetically aligned type I collagen gel or control collagen gel were implanted into 4- or 6-mm surgical gaps created in the sciatic nerve of mice and explanted 30 and 60 days postoperation (dpo) for histological and immunohistochemical evaluation. The hypothesis was that contact guidance of regenerating axons and/or invading nonneuronal cells to the longitudinally aligned collagen fibrils would improve nerve regeneration. The criterion for regeneration was observation of regenerating myelinated fibers distal to the nerve guide. Consistent with previous studies showing poor regeneration in 6-mm gaps at 60 dpo with entubulation repair, only one of six mice exhibited regeneration with control collagen gel. In contrast, four of four mice exhibited regeneration with magnetically aligned collagen gel, including the appearance of nerve fascicle formation. The numbers of myelinated fibers were less than the uninjured nerve in all groups, however, which may have been due to rapid resorption of the nerve guides. An attempt to increase the stability of the collagen gel, and thereby the directional information presented by the aligned collagen fibrils, by crosslinking the collagen with ribose before implantation proved detrimental for regeneration.

Olfactory bulb ensheathing cells enhance peripheral nerve regeneration.

Sciatic nerve resection leaving a 15 mm gap could not be repaired by bridging the stumps with a silicone tube prefilled with a laminin gel. However, when purified olfactory ensheathing cells (EC) were added to the gel filling the tube, successful axonal regeneration was observed in 50% of rats. With 12 mm gaps, regeneration occurred in 79% of rats with transplanted EC compared with 60% of those receiving collagen gel alone. Therefore, ECs help repair severe peripheral nerve injuries, in addition to their ability to promote axonal regeneration within the central nervous system.

Physiological and immunohistochemical characterization of cisplatin-induced neuropathy in mice.

We investigated the neuropathic effects of cisplatin in two groups of mice treated with 5 or 10 mg/kg/week of cisplatin for 7 or 8 weeks. Peripheral nerve functions were evaluated by sweat imprints, and electrophysiological, rotarod, and nociceptive tests. Protein gene product 9.5 (PGP), calcitonin gene-related peptide (CGRP), and vasoactive intestinal peptide (VIP) were immunohistochemically localized in footpads. Tibial nerves were analyzed morphometrically. Functional deficits developed progressively with higher cumulative doses, more markedly in mice treated with high than in those with low doses. From cumulative doses of 10 mg/kg, significant declines in sensory nerve conduction velocity and sudomotor responses were found, whereas motor and nociceptive functions were involved later. There were no morphometrical changes in tibial nerves. A marked decrease of CGRP- and VIP-immunoreactive nerves occurred in samples from treated mice, whereas PGP-labeled profiles decreased mildly at late stages. Impairment of the content of neuropeptides with neurosecretor role was detectable earlier than functional abnormalities. Immunohistochemical analysis of skin biopsies offers a useful diagnostic tool for peripheral neuropathies.

Morphometric and ultrastructural changes with ageing in mouse peripheral nerve.

Qualitative and quantitative information is reported on the morphological changes that occur in nerve fibres and nonneuronal cells of peripheral nerve during the lifetime of the mouse. Tibial nerves of mice aged 6-33 mo were studied. With ageing, collagen accumulates in the perineurium and lipid droplets in the perineurial cells. Macrophages and mast cells increase in number, and onion bulbs and collagen pockets are frequently present. Schwann cells associated with myelinated fibres (MF) slightly decrease in number in parallel with an increase of the internodal length from 6 to 12 mo, but increase in older nerves when demyelination and remyelination are common. The unmyelinated axon to myelinated fibre (UA/MF) ratio was about 2 until 12 mo, decreasing to 1.6 by 27 mo. In older mice, the loss of nerve fibres involves UA (50% loss of 27-33 mo cf. 6 mo) more markedly than MF (35%). In aged nerves wide incisures and infolded or outfolded myelin loops are frequent, resulting in an increased irregularity in the morphology of fibres along the internodes. In the mouse there is an adult time period, 12-20 mo, during which several features of degeneration progressively appear, and an ageing period from 20 mo upwards when the nerve suffers a general disorganisation and marked fibre loss.

Peripheral nerve regeneration through bioresorbable and durable nerve guides.

We compared reinnervation of target organs after sciatic nerve resection and repair by tubulization with biodurable tubes of silicone and teflon, or bioresorbable nerve guides of collagen and poly(L-lactide-co-6-caprolactone) (PLC) leaving a 6 mm gap in different groups of mice. All tubes were of 1 mm inside diameter and thin-walled (50 to 250 microm). Functional reinnervation was assessed by noninvasive methods to determine recovery of sweating, sensory and motor functions in the hindpaw repeatedly during 5 months postoperation. PLC guides allowed faster and higher levels of reinnervation for the four functions tested than collagen and silicone tubes, while teflon tubes gave the lowest levels of recovery. Regenerative reinnervation by thin nociceptive and sudomotor fibers was higher than by large sensory and alphamotor fibers in all groups. Resorbable tubes promoted regeneration in a higher proportion of mice than durable tubes. In cases with effective regeneration the nerve cable was multifascicular, with mild to moderate mononuclear cell infiltrates and a thin newly formed perineurium. The number of myelinated fibers was higher in PLC and silicone tubes than in collagen and teflon tubes. There was only minimal inflammatory reaction within the remnants of collagen tubes, but not in the other materials. PLC tubes of slow reabsorption rate seem useful for repairing long gaps in injured nerves.