Versatilidad anatómica del colgajo lateral del brazo. Estudio cadavérico en una muestra de población colombiana / Anatomical versatility of the lateral arm flap. Cadaver study in a sample of the Colombian population

Introducción y objetivo: El colgajo lateral del brazo es un recurso de cobertura para el cirujano de mano que tiene una amplia variedad de usos y aplicaciones por su versatilidad y facilidad de recolección con poca morbilidad del sitio donante. El objetivo de este estudio es documentar las principales variantes anatómicas y establecer puntos de referencias para el desarrollo y mejoramiento de las técnicas quirúrgicas actuales en una muestra de población colombiana. Material y métodos: Estudio descriptivo anatómico de 10 miembros superiores de cadáveres frescos congelados en los que realizamos disecciones para documentar las principales perforantes del colgajo lateral del brazo en población colombiana. Tomamos mediciones de distancia de las perforantes al epicóndilo lateral y sacamos proporciones según porcentajes del tamaño de la extremidad. Igualmente, cuantificamos número de perforantes en cada cuadrante y diámetro de los pedículos. Resultados: En el colgajo lateral del brazo, el orden de aparición de las perforantes de distal a proximal correspondió al 13, 19, 26 y 35% de la distancia del brazo (entre el epicóndilo y el acromion); en el segundo cuadrante encontramos la mayoría de las perforantes, la segunda y la cuarta, tuvieron menor variación con respecto a las demás perforantes, los pedículos proximales presentaron un mayor diámetro que los distales. Encontramos el nervio radial a la salida del tabique intermuscular en promedio a 14.08 cm (+/- 0.83) del epicóndilo, siendo esta referencia clave para una disección cuidadosa con el fin de evitar la lesión del mismo. Conclusiones: En nuestra población de estudio, el colgajo lateral del brazo posee una gran versatilidad, con un buen número de perforantes para su nutrición que le permite al cirujano múltiples opciones de cobertura...(AU)

Background and objective: The lateral arm flap is a coverage resource for the hand surgeon that has a wide variety of uses and applications due to its versatility and ease of collection with little morbidity from the donor site. The aim of this research is to carry out dissections of the lateral arm flap in cadavers of the Colombian population to describe the main anatomical vari-ants and establish reference points for the development and improvement of current surgical techniques. Methods: Anatomical descriptive study of 10 upper limbs from fresh-frozen cadavers in which dissections were performed to document the main perforators of the lateral flap of the arm in the Colombian population. Distance measurements were taken from the perforators to the lateral epicondyle and ratios were obtained according to percentages of limb size. Likewise, the number of perforators in each quadrant and the diameter of the pedicles were quantified. Results: The results showed that in the lateral arm flap the order of appearance of the perforators from distal to proximal corresponds to 13, 19, 26 and 35% of the distance of the arm (between the epicondyle and the acromion); most of the perforators were found in the second quadrant, the second and fourth have less variation compared to the other perforators, the proximal pedicles have a larger diameter than the distal ones, the radial nerve was found at the exit the intermuscular septum on average 14.08 cm (+/- 0.83) from the epicondyle, this is a key reference for a careful dissection in order to avoid injury to it. Conclusions: In our study population, the lateral arm flap is highly versatile with a good number of perforators for its nutrition, which allows the surgeon multiple coverage options. The bone perforators of the distal humerus must be protected in the most distal portion to avoid complications such as bone necrosis, especially in children...(AU)

Randomized clinical trial to assess the protective efficacy of a Plasmodium vivax CS synthetic vaccine.

A randomized, double-blind, controlled vaccine clinical trial was conducted to assess, as the primary outcome, the safety and protective efficacy of the Plasmodium vivax circumsporozoite (CS) protein in healthy malaria-naïve (phase IIa) and semi-immune (phase IIb) volunteers. Participants (n = 35) were randomly selected from a larger group (n = 121) and further divided into naïve (n = 17) and semi-immune (n = 18) groups and were immunized at months 0, 2, and 6 with PvCS formulated in Montanide ISA-51 adjuvant or placebo (adjuvant alone). Specific antibodies and IFN-γ responses to PvCS were determined as secondary outcome; all experimental volunteers developed specific IgG and IFN-γ. Three months after the last immunization, all participants were subjected to controlled human malaria infection. All naive controls became infected and drastic parasitemia reduction, including sterile protection, developed in several experimental volunteers in phase IIa (6/11) (54%, 95% CI 0.25-0.84) and phase IIb (7/11) (64%, 95% CI 0.35-0.92). However, no difference in parasitemia was observed between the phase IIb experimental and control subgroups. In conclusion, this study demonstrates significant protection in both naïve and semi-immune volunteers, encouraging further PvCS vaccine clinical development. Trial registration number NCT02083068. This trial was funded by Colciencias (grant 529-2009), NHLBI (grant RHL086488 A), and MVDC/CIV Foundation (grant 2014-1206).

Consistent prevalence of asymptomatic infections in malaria endemic populations in Colombia over time.

BACKGROUND: Malaria control programmes rely on confirmation of parasite presence in patients' blood prior to treatment administration. Plasmodium parasites are detected mostly by microscopy or rapid diagnostic test (RDT). Although these methods contribute significantly to malaria control/elimination, they are not suitable for detecting the significant proportion of asymptomatic subjects harbouring low levels of parasitaemia, which endure untreated as potential reservoirs for transmission. Malaria prevalence was assessed in endemic regions of Colombia over a 4-year follow-up. METHODS: A series of cross-sectional surveys were conducted between 2011 and 2014 in low to moderate malaria transmission sentinel sites (SS) of Tumaco, Buenaventura and Tierralta municipalities of Colombia. A census was performed and a random sample of houses was selected from each SS prior to each survey. Inhabitants were asked to answer a questionnaire on clinical, epidemiological and demographic aspects, and to provide a blood sample for malaria diagnosis using microscopy and quantitative real time polymerase chain reaction (qPCR). RESULTS: A total of 3059 blood samples were obtained from all SS, 58.5 % of which were from women and displayed a malaria prevalence ranging from 4 % (95 % CI 3-5 %) to 10 % (95 % CI 8-12 %) in the 4 years' study period. Almost all malaria cases (n = 220, 97 %) were sub-microscopic and only detectable by qPCR; 90 % of the cases were asymptomatic at the time of blood collection. While Buenaventura and Tierralta had a decreasing tendency during the follow-up, Tumaco had a rise in 2013 and then a decrease in 2014. Plasmodium vivax accounted for the majority (66-100 %) of cases in Tierralta and Buenaventura and for 25-50 % of the cases in Tumaco. CONCLUSIONS: This study demonstrates an important prevalence of asymptomatic malaria cases not detectable by microscopy, which therefore remain untreated representing a parasite pool for malaria transmission. This demands the introduction of alternative strategies for diagnosis and treatment, especially for areas of low transmission to reduce it to appropriate levels for malaria pre-elimination efforts to start.