[Intraosseous vancomycin in total knee arthroplasty]. / Vancomicina intraósea en artroplastía total de rodilla.

INTRODUCTION: intravenous antibiotic prophylaxis has significantly reduced the incidence of periprosthetic joint infection (PJI) in knee surgeries. However, for patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) or those at risk of colonization, prophylaxis should include vancomycin. Intraosseous (IO) administration of vancomycin could enhance its effectiveness in total knee arthroplasty (TKA). MATERIAL AND METHODS: a retrospective review was conducted, including 143 patients at risk of PJI scheduled for TKA who received IO vancomycin along with intravenous (IV) cefazolin, referred to as group I (GI), between May 2021 and December 2022. The occurrence of complications in the first three postoperative months was evaluated. Results were compared with 140 patients without risk factors who received standard IV prophylaxis, designated as group II (GII). RESULTS: in GI, 500 mg of IO vancomycin was administered, injected into the proximal tibia, in addition to standard IV prophylaxis. In GII, patients received only IV cefazolin. The incidence of complications was 1.64% in GI and 1.4% in GII. The PJI rate at 90 postoperative days was 0.69% in GI and 0.71% in GII. CONCLUSIONS: IO vancomycin administration, along with standard IV prophylaxis, provides a safe and effective alternative for patients at risk of MRSA colonization. This approach minimizes complications associated with IV vancomycin use and addresses logistical challenges of timely administration.

INTRODUCCIÓN: la profilaxis antibiótica intravenosa ha reducido significativamente la incidencia de infección articular periprotésica (IAP) en cirugías de rodilla. No obstante, para pacientes colonizados con Staphylococcus aureus resistente a meticilina (SARM) o aquellos con riesgo de colonización, la profilaxis debe incluir vancomicina. La administración intraósea de vancomicina podría potenciar su efectividad en la artroplastía total de rodilla. MATERIAL Y MÉTODOS: se realizó una revisión retrospectiva que incluyó a 143 pacientes en riesgo de IAP programados para artroplastía total de rodilla que recibieron vancomicina intraósea junto a cefazolina intravenosa (IV), a quienes denominamos grupo I (GI), entre mayo de 2021 y diciembre de 2022. Se evaluó la aparición de complicaciones en los primeros tres meses postoperatorios. Los resultados se compararon con 140 pacientes sin factores de riesgo que recibieron profilaxis intravenosa estándar, denominados grupo II (GII). RESULTADOS: en el GI, se administraron 500 mg de vancomicina intraósea, inyectados en la tibia proximal, además de la profilaxis intravenosa estándar. En el GII, los pacientes recibieron sólo cefazolina intravenosa. La incidencia de complicaciones fue de 1.64% en el GI y de 1.4% en el GII. La tasa de IAP a los 90 días postoperatorios fue de 0.69% en el GI y de 0.71% en el GII. CONCLUSIONES: la administración de vancomicina intraósea, junto con la profilaxis intravenosa estándar, ofrece una alternativa segura y eficaz para pacientes con riesgo de colonización por SARM. Este enfoque minimiza las complicaciones asociadas con el uso intravenoso de vancomicina y soluciona los desafíos logísticos de la administración oportuna.

[Partial exchange of components in chronic hip infection]. / Intercambio parcial de componentes en infección crónica de cadera.

INTRODUCTION: one- or two-stage total revision is considered the gold standard for the treatment of hip arthroplasty with chronic infection. However, during the removal of a fixed prosthetic component, the host bone may be damaged, making definitive prosthetic reimplantation difficult. OBJECTIVE: we present a series of patients treated for chronic periprosthetic hip infection with preservation of one fixed component. MATERIAL AND METHODS: this study included 12 patients with hip arthroplasty and chronic periprosthetic infection scheduled for one or two-stage partial replacement with retention of a fixed component between June 2015 and January 2021. The minimum follow-up period was 2 years (mean, 4.08 years). None of the 12 patients in this series was lost to follow-up. We evaluated the evolution through clinical examination, Harris Hip Score, laboratory and radiological studies. RESULTS: at a mean follow-up of 4.08 years after prosthetic reimplantation, two of the 12 patients had recurrence of infection (16.6%), and the mean Harris hip score reached 63.6 points at the last follow-up assessment. CONCLUSIONS: fixed implant preservation may be an acceptable option for patients with chronic periprosthetic hip infection when removal of the fixed component results in significant bone loss compromising future reimplantation. However, more studies are required on this treatment method.

INTRODUCCIÓN: la revisión total en una o dos etapas se considera el estándar de oro para el tratamiento de la artroplastía de cadera con infección crónica. Sin embargo, durante la extracción de un componente protésico fijo, el hueso del huésped puede dañarse, lo que dificulta la reimplantación definitiva de la prótesis. OBJETIVO: presentamos una serie de pacientes tratados por infección crónica periprotésica de cadera con la preservación de un componente fijo. MATERIAL Y MÉTODOS: este estudio retrospectivo incluyó a 12 pacientes con artroplastía de cadera e infección periprotésica crónica programadas para revisión parcial en una o dos etapas con retención de un componente fijo entre Junio de 2015 y Enero de 2021. El período mínimo de seguimiento fue de dos años (media, 4.08 años). Ninguno de los 12 pacientes de esta serie se perdió en el seguimiento. Evaluamos la evolución a través del examen clínico, puntuación de cadera de Harris, estudios de laboratorio y radiológicos. RESULTADOS: con un seguimiento promedio de 4.08 años después de la reimplantación protésica, dos de los 12 pacientes presentaron recurrencia de la infección (16.6%) y la puntuación media de Harris en la cadera alcanzó 63.6 puntos en la última evaluación de seguimiento. CONCLUSIONES: la preservación del implante fijo puede ser una opción aceptable para pacientes estrictamente seleccionados con infección periprotésica crónica de cadera cuando la extracción del componente fijo produce una pérdida ósea significativa que compromete la reconstrucción futura. Se necesitan más estudios sobre este método de tratamiento.

Detección ecográfica y pronóstico de la ventriculomegalia fetal / Ultrasound detection and prognosis of fetal ventriculomegaly

Antecedentes: La ventriculomegalia fetal es un signo ecográfico muy sensible para las alteraciones del sistema nervioso central fetal. La morbilidad asociada a la misma depende principalmente de la etiología y de la presencia de otras malformaciones asociadas. Si es aislada y no progresiva se puede preveer un resultado posnatal favorable hasta en el 70 por ciento de los casos aunque hay una gran disparidad de cifras entre distintos centros y autores. Objetivo: Establecer la relación entre ventriculomegalia y pronóstico perinatal. Método: Se han revisado 60 casos diagnosticados mediante ecografía prenatal en el Hospital Universitario de Canarias siguiendo los criterios ecográficos de ventriculomegalia (astas posteriores mayores de 10 mm). Se realizaron cariotipos y serología materna y en líquido amniótico para completar el estudio. Resultados: Hubo un total de 23 interrupciones voluntarias de la gestación y 28 recién nacidos sin secuelas (47 por ciento). Un 70 por ciento de las ventriculomegalias aisladas correspondieron a recién nacidos sin secuelas. El 10 por ciento de las ventriculomegalias aparecieron en fetos con aneuploidías. Conclusión: El pronóstico fue favorable en los casos de ventriculomegalia no progresiva y aislada. La medida de la ventriculomegalia no predice el resultado. La variabilidad de resultados en la literatura obliga a cada centro a disponer de sus protocolos y datos para aconsejar a la pareja que ha de tomar una decisión sobre el futuro de su embarazo.

Background: Fetal ventriculomegaly is the most sensitive sonographic sign for central nervous system anomalies. Neonatal morbidity and mortality depends on the etiology of the ventriculomegaly and the presence of other malformations. Isolated non-progressive ventriculomegaly is associated with 70 percent favorable results, with a great disparity among studies. Aims: To establish the relationships between ventriculomegaly and perinatal outcome. Methods: The authors reviewed 60 cases of prenatally diagnosed fetal ventriculomegaly in the Canary Islands University Hospital. An ultrasonographic measurement of the lateral ventricles of 10 mm or more was considered as ventriculomegaly. Fetal and maternal serology was performed as well as fetal karyotyping. Results: 23 patients decided to terminate the pregnancy due to unfavorable prognosis. In 28 cases outcome was favorable. 70 percent of isolated ventriculomegaly corresponded to healthy newborns. 10 percent of the fetuses had aneuploidies. Conclusion: Prognosis is favorable if ventriculomegaly is isolated and non-progressive. Measurement of the lateral ventricle does not predict outcome. Disparity of results in literature makes it necessary for each Hospital to rely on their own data and guidelines to assess parents on the fate of the pregnancy.

[Conventional and quantitative electroencephalography in patients with Steinert's myotonic dystrophy]. / Electroencefalografía convencional y cuantitativa en pacientes con distrofia miotónica de Steinert.

INTRODUCTION: Steinert's myotonic dystrophy (SMD) is a systemic-type dominant autosomal disease, with variable clinical expression. Recent magnetic resonance studies conducted in patients with this disease have described the presence of lesions in the white matter of the brain and there have also been reports of a correlation between these and the presence of cognitive disorders. Nevertheless, very little work has been published about the electroencephalographic (EEG) findings in this disease. PATIENTS AND METHODS: In this study both conventional and quantitative EEG were performed on 10 patients with SMD aged between 17 and 50 years. RESULTS: 90% of the patients showed a posterior alpha rhythm that was disorganised but which reacted on opening and closing the eyes, as well as the presence of continuous theta activity over the base activity that was bilaterally more pronounced towards the frontal-central regions. In the quantitative analysis we observed an increase in the absolute energies for the slow bands and a decrease for the fast bands on the frequency spectrum. In most patients (80%) spectral peaks were found within the theta range of frequencies as a correlate of the slow activity observed in the conventional analysis. CONCLUSIONS: It can be concluded that a quantitative EEG could be useful in the study of what, for many years, has been considered to be a 'neuromuscular' disease and that the use of other more precise methods, such as cerebral coherence and brain electrical tomography, could shed new light on the functional management of these patients.

Pilomatrixoma: diagnóstico ecotomográfico / Pilomatrixoma: ultrasound diagnosis

BACKGROUND: Pilomatrixoma is a benign tumor of the skin, preferentially found in children. The final diagnosis is made by biopsy. High resolution ultrasound (US) is a non invasive method for its diagnosis. AIM: To describe the US findings in children with pilomatrixoma. MATERIAL AND METHODS: Fifty five patients with 62 clinically suspected pilomatrixomas were studied by US. All examinations were done with an ATL HDI 5000, linear 5-12 MHz transducer. Pathological study confirmed the diagnosis pilomatrixoma in 52 cases. RESULTS: Fifty of 52 pilomatrixomas were diagnosed by US, with a sensitivity of 96 per cent. The mean age of patients was 7.5 years. Forty seven lesions (90 per cent) were located in the head, neck or upper extremities and their mean size was 8.5 mm. Thirty two lesions were hypodermal, 14 were dermohypodermal and 6 were dermal. In 44 lesions the contour was regular and non delineated, 44 lesions were oval, 41 lesions had an acoustic shadow, 36 were echogenic or hyperechogenic, 31 had a peripheral halo (60 per cent), 55 had calcifications (98 per cent), nine had perilesional vessels, 2 had intratumoral vessels and 7 had inflammatory changes. US excluded the diagnosis of pilomatrixoma in 10 lesions formulating a correct differential diagnosis in eight, with a specificity of 80 per cent. CONCLUSIONS: Pilomatrixomas had two US types of presentation. The first is a well defined nodule with peripheral halo partially calcified or with microcalcifications. The second is a completely calcified nodule without peripheral halo and with a strong acoustic shadow. US is a useful, sensitive and specific diagnostic method for pilomatrixoma.

Distribution and diversity of cry genes in native strains of Bacillus thuringiensis obtained from different ecosystems from Colombia.

Colombia is a tropical country located at the north of South America. It is considered to be one of the most important countries in terms of its biodiversity worldwide. One hundred and eight soil samples obtained from agricultural crops and wild ecosystems were evaluated in terms of the presence of Bacillus thuringiensis (Bt) native strains. One hundred and eight different Bt strains were isolated and characterized by the presence of crystal proteins by SDS-PAGE and a multiplex PCR with general and specific primers for cry1 and cry3, cry7, and cry8 gene detection. Most of the Bt strains (73%) reacted with the cry1 general primers; 27.8% of the Bt strains reacted with cry3, cry7, and cry8 general primers and 17.8% of strains did not react with any of these two sets of primers. Thirty different PCR profiles were found in the strains with cry1 genes when they were analyzed with specific primers (cry1A to cry1F). A high frequency of joint occurrence was observed for cry1Aa/cry1Ab, cry1Aa/cry1Ac, cry1Ab/cry1Ac, and cry1C/cry1D genes with a Pearson coefficient of 0.88, 0.74, 0.76, and 0.87, respectively. Other distinctive characteristics were found in the Colombian collection as the presence of 22.2% of native strains which presented, at the same time, lepidopteran and coleopteran active genes. Interesting relations were found as well between the cry gene distribution and the geographical areas sampled. Finally, some strains with moderate to high biopesticide activity against Spodoptera frugiperda (Lepidoptera) and Premnotrypes vorax (Coleoptera) insects were identified, this being important to explore future microbial strategies for the control of these crop pests in the region.

Fistula enterocutanea en abdomen abierto / Enterocutanea fistula in trauma

Se analizó una serie clínica de 23 pacientes con diagnóstico de abdomen abierto complicado con fístula intestinal para evaluar su respuesta a la terapia nutricional en lo que respecta al comportamiento de la fístula y a la incidencia sobre la mortalidad global y otras variables de la hospitalización. La edad promedio fue de 44 años. El análisis inicial mostró una preponderancia de la etiología posquirúrgica no traumática sobre la traumática (61 por ciento vs. 39 por ciento). Un 56 por ciento de pacientes se diagnosticó como malnutrido, con una albúmina de ingreso promedio de 1.9 gr/dl. La fístula fue de alto gasto en el 78 por ciento de los casos, 83 por ciento(21) requirió más de 2 cirugías, con un promedio de 4.7 cirugías / paciente. El soporte nutricional mixto fue el más frecuente 16 (74 por ciento) con un promedio de 1282 cal. /día, 14.3 gramos/ N/día y 17 días/pte. El porcentaje global de cierre fue del 65 por ciento (15), 8 (35 por ciento) con tratamiento conservador y 7 (30 por ciento) con cierre quirúrgico. La estancia hospitalaria fue de 62 días (rango 11-168), los costos de atención oscilan entre (pesos colombianos) 1.619.391 y 58.939.583 y el costo global de atención se calculó en 451.341.680 pesos colombianos. El 60 por ciento (15) de los pacientes tuvieron un costo de atención superior a los 15.000.000. La mortalidad fue del 34 por ciento (8), similar a la reportada mundialmente. El análisis del impacto del soporte nutricional sobre la mortalidad y la estancia no mostró ninguna correlación estadísticamente significativa con variables como tiempo de inicio del soporte, calorías administradas, tipo de cierre, tipo de soporte. Otras usualmente pronosticó como albúmina, proteínas y balance nitrogenado al ingreso y egreso tampoco mostraron correlación con la muerte, la tasa de cierre y el pronóstico. Los datos obtenidos permiten concluir que el abdomen abierto complicado con fístula intestinal en una entidad que demanda un enorme cuidado y manejo multidisciplinario en la que el soporte nutricional intensivo pese a la dificultad en la medición de su valor aditivo a la terapia, es una importante herramienta en el afán de disminuir el perfil de mobimortalidad de este síndrome

PaO2 increases with coughing in patients with chronic lung disease.

We considered if the cyanosis frequently observed during a cough attack in patients with chronic lung disease was due to worsening hypoxemia. To investigate the effects of cough on PaO2, we measured arterial blood gases before and after a voluntary coughing period of 45 sec, in 11 patients with Interstitial Lung Disease (ILD) and 14 patients with Chronic Obstructive Lung Disease (COPD). All patients significantly increased (p less than 0.05) their PaO2 (COPD: from 49 +/- 2 to 60 +/- 2 mmHg; ILD from 44 +/- 2 to 51 +/- 3 mmHg, mean +/- SD) and decreased their PaCO2. We conclude that stable patients with COPD and ILD increase their PaO2 with coughing most likely due to hyperventilation. The cyanosis observed could be due to peripheral circulatory effects of coughing.

[Hydralazine and oxygen transport in interstitial and chronic obstructive pneumopathies]. / La hidralazina y el transporte de oxígeno en la neumopatía intersticial y obstructiva pulmonar crónica.

We studied the effect of hydralazine (HDL) on peripheral oxygen transport (TO2) in 8 patients with chronic obstructive lung disease (EPOC, group I) and 11 patients with chronic interstitial lung disease (NI, group II) and pulmonary arterial hypertension (HAP). Mean pulmonary artery pressure (Pp) at basal conditions were 31 +/- 3 mmHg for the EPOC group and 26 +/- 9 mmHg for NI patients. After HDL, pulmonary vascular resistance (Rp) decreased significantly only in NI patients (Rp basal = 7.1 +/- 4, Rp post HDL = 5.9 +/- 3u m2). In EPOC patients Pp increased after HDL (Pp basal = 31 +/- 3, Pp post HDL = 36 +/- 4 mmHg, p less than 0.05). This was not the case for NI patients in whom Pp did not change. Both groups showed reduction in systemic vascular resistance after HDL. PaO2, PvO2, SaO2, CvO2 and TO2 were significantly increased in both groups after HDL. TO2 change was correlated with the increasing cardiac index in both diseases and with arterial oxygen content in group II only. Our study suggest that TO2 improves in EPOC and NI patients after HDL, however only in NI was associated with a reduction in pulmonary vascular resistance.

[Effect of chronic altitude hypoxia on the behavior of the respiratory center. Study on normal subjects living at the altitude of Mexico City (2,240 meters)]. / Efecto de la hipoxia crónica de la altitud en el comportamiento del centro respiratorio. Estudio en sujetos normales residentes a la altitud de la ciudad de México, D.F. (2,240 mts).

Respiratory center (RC) output has been shown to be increased in hypoxemic Chronic Obstructive patients at sea level. In order to asses the separate role of chronic hypoxia on the RC output we studied 30 normal subjects all of them native and residents of Mexico City (altitude: 2,240 m, PaO2: 65-70 torr.). The parameters studied were: occlussion pressure (P0.1), mean inspiratory flow (Vi), and the ratio inspiratory time to total duration of the respiratory cycle (Ti/Ttot). The inspiratory impedance of the respiratory system as well as the minute ventilation (VE) and lastly to ensure isocapnic conditions, the end-tidal CO2 (PECO2), were also measured. These parameters were determined: 1) While breathing room air (RA), 2) after 30 min of breathing an inspired oxygen fraction (FiO2) of 30% and again 3) after 30 min of breathing and FiO2 of 100%. Fifteen of the subjects were studied on supine and the other 15 in the seated position. In most of the subjects the baseline (RA) values of P0.1 were found to be higher than those reported for normals at sea level. In every case, independent of body position, the P0.1 decreased (less than 0.01) to normal sea level values after 30 min of breathing O2 30%. Likewise, Vi and mechanical impedance also decreased (p less than 0.01) and no changes in Ti/Ttot were noted at this FiO2. No further changes occurred after breathing 100%. The above results show that: 1) The RC output in normal people at altitude (i.e. without mechanical abnormalities but with chronic hypoxia) is increased as compared to sea level.(ABSTRACT TRUNCATED AT 250 WORDS)

[Use of blood oxygen partial pressure in the right atrium in the calculation of intrapulmonary shunt]. / Utilidad de la presión parcial de oxígeno en la sangre de la aurícula derecha en el cálculo del cortocircuito intrapulmonar.

In order to assess the usefulness of blood samples taken from the right atrium (RA) in the calculation of intrapulmonary shunt (Qs/Qt), we correlated the values of Qs/Qt obtained through RA sampling with those obtained form a simultaneous sample of blood from the pulmonary artery (PA). The study was done in six mongrel dogs (15 to 23 Kg) who were anesthetized and artificially ventilated. The Qs/Qt measurements were repeated at different levels of cardiac output (CO). Changes in CO were elicited by both mechanical (A-V fistula) and pharmacological (Hydralazine) means. Besides the Qs/Qt correlation we also correlated the oxygen-hemoglobin saturation (Sat %) and oxygen tension (PvO2) values between the two sites of mixed venous sampling. The correlations of the different parameters between RA and PA samples we obtained were as follows: Qs/Qt r = 0.93 (p less than 0.001); Sat % r = 0.87 (p less than 0.001); and for PvO2 r = 0.91 (p less than 0.001). The significant correlations of these parameters were maintained independent of the CO level. We conclude that in our model a sample of blood obtained from the RA is useful for the calculation of Qs/Qt.