Use of multiple pharmacodynamic measures to deconstruct the Nix-TB regimen in a short-course murine model of tuberculosis.

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen [bedaquiline-pretomanid-linezolid (BPaL)] during the first 3 weeks of treatment at human equivalent doses. The rRNA synthesis (RS) ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, together with solid culture CFU counts and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time-course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

Use of Multiple Pharmacodynamic Measures to Deconstruct the Nix-TB Regimen in a Short-Course Murine Model of Tuberculosis.

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen (bedaquiline-pretomanid-linezolid [BPaL]) during the first three weeks of treatment at human equivalent doses. RS ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, to-gether with solid culture CFU and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

Caracterización clínica y epidemiológica de los pacientes con trastorno por uso de opioides atendidos en una institución de cuarto nivel en la ciudad de Medellín, entre 2017 y 2022 / Clinical and epidemiological characterization of patients with opioid use disorder treated at a fourth level institution in the city of Medellín, between 2017 and 2022

Los analgésicos opioides son una opción importante en el manejo del dolor agudo grave, crónico e intratable, sin embargo, sus efectos euforizantes y gratificantes han motivado a que algunos pacientes continúen su uso una vez resuelta la condición médica inicial, haciendo entonces un uso indebido de opioides (UIO) y con el potencial riesgo de desarrollar un trastorno por uso de opioides (TUO). El objetivo del presente trabajo fue caracterizar clínica y epidemiológicamente a los pacientes con trastorno por uso de opioides atendidos en una institución de cuarto nivel de Medellín. Para ello, se realizó un estudio observacional, descriptivo, transversal de fuente secundaria; se incluyeron 309 registros de pacientes adultos, con diagnóstico CIE-10, trastornos causados por opiáceos. TUO e UIO constituyeron las variables de interés, se procesó la información en Jamovi® versión 2.2 y se analizaron los datos de variables cuantitativas con test de Sahpiro Wilk y análisis bivariado exploratorio de las variables clínicas y sociodemográficas. Resultados: El TUO obtuvo una prevalencia del 39.9% frente al 25,6 % del UIO. De los pacientes con TUO el 50% tenían 35 años o menos, el 57.7% fueron mujeres, 58.7% solteros, y predominaron los niveles de educación secundaria y universitaria. En cuanto al UIO, el 50% fueron menores de 37 años el 54% de sexo femenino, en su mayoría solteros (61.5%), y predominó el nivel de educación secundaria (48.7%). En el 71% de los pacientes con TUO hay antecedentes de enfermedad mental predominando los trastornos del afecto: ansiedad y depresión. El opioide más usado fue tramadol (17.04%), seguido de morfina e hidromorfona. Conclusión: Ante el aumento en la prevalencia de UIO y TUO es necesario nuevas políticas salud pública que permitan ejercer un control más estricto en la formulación, comercialización y administración segura de este tipo de medicamentos.(AU)

Opioids analgesics are an important option in the management of severe acute, chronic, and intractable pain; however, their euphoric and rewarding effects have motivated some patients to continue their use once the initial medical condition has resolved, thus misusing them. these (UIO) and with the potential risk of developing an opioid use disorder (OUD).Objectives: to clinically and epidemiologically characterize patients with opioid use disorder treated at a fourth-level institution in Medellín.Methodology: Observational, descriptive, cross-sectional study of secondary source; 309 records of adult patients with ICD-10, diagnosis caused by opioids agents were included. TUO and IOU were the variables of interest, the information was processed in Jamovi® version 2.2 and the data of quantitative variables were analyzed with the Sahpiro Wilk test and exploratory bivariate analysis of the clinical and sociodemographic variables.Results: The TUO obtained a prevalence of 39.9% compared to 25.6% of the UIO. Of the patients with OT, 50% were 35 years of age or younger, 57.7% were women, 58.7% were single, and secondary and university education levels predominated. Regarding the UIO, 50% were under 37 years of age, 54% female, mostly single (61.5%), and the secondary education level predominated (48.7%).In 71% of patients with OLW there is a history of mental illness, predominantly affective disorders: anxiety and depression. The most used opioid was tramadol (17.04%), followed by morphine and hydromorphone. Conclusion: Given the increase in the prevalence of UIO and OTU, new public health policies are necessary to exercise stricter control in the formulation, marketing and safe administration of this type of medication.(AU)

Alcaptonuria: evolución y curso de la enfermedad hacia artropatía ocronótica. Serie de casos manejados con reemplazo articular / Alkaptonuria: evolution and course of the disease towards ochronotic arthropathy. Series of cases managed with joint replacement

Resumen: Introducción: la alcaptonuria es una enfermedad metabólica inusual, de herencia autosómica recesiva dada por la deficiencia de la oxidasa de HGA. Clásicamente descrita y diagnosticada sobre la tercera a cuarta década de la vida, la cual tiene afectación en ambos sexos, su impresión diagnóstica es clínica, basándose en la coloración azul/negro de las conjuntivas; sin embargo, se confirma mediante el análisis específico de la enzima en la orina, actualmente no existe un tratamiento definitivo, sólo alternativas en cuanto a lo paliativo y sintomático. Material y métodos: estudio descriptivo, observacional, de tipo serie de casos, como objetivo primario se describe la progresión de la enfermedad y su compromiso en el sistema musculoesquelético. Resultados: se presentan dos casos clínicos en mujer y hombre, los cuales ilustran: variedad clínica, avance progresivo y las alteraciones que puede generar en el sistema musculoesquelético. Conclusiones: la alcaptonuria es una enfermedad rara, la cual conlleva una artropatía secundaria severa, sin un tratamiento definitivo dirigido a tratar los síntomas, incluso en sus estadios finales los reemplazos articulares son una opción para proporcionar manejo del dolor obteniendo resultados satisfactorios.

Abstract: Introduction: alkaptonuria is a very rare metabolic disease with autosomal recessive inheritance due to HGA oxidase deficiency. Classically described and diagnosed in the third to fourth decade of life, affecting both men and women; Its diagnostic impression is clinical based on the blue/black coloration of the conjunctivae, however it is confirmed by the specific analysis of the enzyme in the urine, to date there is no cure and its treatment is palliative and symptomatic. Material and methods: descriptive, observational, case series study, the primary objective of which is to describe the progression of the disease and its involvement in the musculoskeletal system. Results: two clinical cases are presented in women and men in which the broad clinic is illustrated, its progressive advance and the different alterations that it can generate in the musculoskeletal system. Conclusions: alkaptonuria is a rare disease which leads to a severe secondary arthropathy, currently without a specific management which is based on treating the symptoms, in its final stages joint replacements are a management option with satisfactory results for the relief of pain.

[Alkaptonuria: evolution and course of the disease towards ochronotic arthropathy. Series of cases managed with joint replacement]. / Alcaptonuria: evolución y curso de la enfermedad hacia artropatía ocronótica. Serie de casos manejados con reemplazo articular.

INTRODUCTION: alkaptonuria is a very rare metabolic disease with autosomal recessive inheritance due to HGA oxidase deficiency. Classically described and diagnosed in the third to fourth decade of life, affecting both men and women; Its diagnostic impression is clinical based on the blue/black coloration of the conjunctivae, however it is confirmed by the specific analysis of the enzyme in the urine, to date there is no cure and its treatment is palliative and symptomatic. MATERIAL AND METHODS: descriptive, observational, case series study, the primary objective of which is to describe the progression of the disease and its involvement in the musculoskeletal system. RESULTS: two clinical cases are presented in women and men in which the broad clinic is illustrated, its progressive advance and the different alterations that it can generate in the musculoskeletal system. CONCLUSIONS: alkaptonuria is a rare disease which leads to a severe secondary arthropathy, currently without a specific management which is based on treating the symptoms, in its final stages joint replacements are a management option with satisfactory results for the relief of pain.

INTRODUCCIÓN: la alcaptonuria es una enfermedad metabólica inusual, de herencia autosómica recesiva dada por la deficiencia de la oxidasa de HGA. Clásicamente descrita y diagnosticada sobre la tercera a cuarta década de la vida, la cual tiene afectación en ambos sexos, su impresión diagnóstica es clínica, basándose en la coloración azul/negro de las conjuntivas; sin embargo, se confirma mediante el análisis específico de la enzima en la orina, actualmente no existe un tratamiento definitivo, sólo alternativas en cuanto a lo paliativo y sintomático. MATERIAL Y MÉTODOS: estudio descriptivo, observacional, de tipo serie de casos, como objetivo primario se describe la progresión de la enfermedad y su compromiso en el sistema musculoesquelético. RESULTADOS: se presentan dos casos clínicos en mujer y hombre, los cuales ilustran: variedad clínica, avance progresivo y las alteraciones que puede generar en el sistema musculoesquelético. CONCLUSIONES: la alcaptonuria es una enfermedad rara, la cual conlleva una artropatía secundaria severa, sin un tratamiento definitivo dirigido a tratar los síntomas, incluso en sus estadios finales los reemplazos articulares son una opción para proporcionar manejo del dolor obteniendo resultados satisfactorios.

Recovering biomethane and nutrients from anaerobic digestion of water hyacinth (Eichhornia crassipes) and its co-digestion with fruit and vegetable waste.

The potential to recover bioenergy from anaerobic digestion of water hyacinth (WH) and from its co-digestion with fruit and vegetable waste (FVW) was investigated. Initially, biogas and methane production were studied using the biochemical methane potential (BMP) test at 2 g volatile solids (VS) L(-1) of substrate concentration, both in the digestion of WH alone and in its co-digestion with FVW (WH-FVW ratio of 70:30). Subsequently, the biogas production was optimized in terms of total solids (TS) concentration, testing 4 and 6% of TS. The BMP test showed a biogas yield of 0.114 m(3) biogas kg(-1) VSadded for WH alone. On the other hand, the biogas potential from the WH-FVW co-digestion was 0.141 m(3) biogas kg(-1) VSadded, showing an increase of 23% compared to that of WH alone. Maximum biogas production of 0.230 m(3) biogas kg(-1) VSadded was obtained at 4% of TS in the co-digestion of WH-FVW. Using semi-continuously stirred tank reactors, 1.3 m(3) biogas yield kg(-1) VSadded was produced using an organic loading rate of 2 kg VS m(-3) d(-1) and hydraulic retention time of 15 days. It was also found that a WH-FVW ratio of 80:20 improved the process in terms of pH stability. Additionally, it was found that nitrogen can be recovered in the liquid effluent with a potential for use as a liquid fertilizer.

A continuous mixture of two different dimers in liquid water.

It is hitherto thought that liquid water is composed of tetrahedrally coordinated molecules with an asymmetric interaction of the central molecule with neighboring molecules. Kühne et al., Nat. Commun., 2013, 4, 1450 suggested that this asymmetry, energetic rather than geometric, is the cornerstone to reconcile the homogeneous and inhomogeneous viewpoints of liquid water. In order to investigate the geometric origin of that asymmetry, we have scrutinized Molecular Dynamics (MD) simulations of water through a careful analysis of the five-dimensional probability distribution function of Euler angles in which the relative positions and orientations of water molecules are obtained. We demonstrate that, beyond the ubiquitous tetrahedral structure with well-defined molecular dimers, there is a series of possible molecular orientations that define the structure. These orientations are generated by rotating the neighboring molecule around the O-H axis that is involved in the hydrogen bond scheme. Two of the possible orientations have a higher probability, giving rise to two kinds of dimers: one close to the lowest energy of a water dimer in vacuum with an almost perpendicular alignment of the dipole moment, and another one with a parallel orientation of the dipole moment which is less tightly bound. These two different dimers have an effect on the orientation of further water dipole moments up to a distance of ≈6 Å. Liquid water can therefore be described as a continuous mixture of two kinds of dimers where the hydrogen bonds have the same geometry but the interaction energies are different due to a different mutual orientation of the dipoles of the participating water molecules.

Insights into the determination of molecular structure from diffraction data using a Bayesian algorithm.

The determination of the molecular ordering in a liquid is still a controversial subject. There is no general consensus either on the methods to obtain reliable liquid structures or on the way to analyze them. Regardless of the method, it is very important to have a realistic molecular structure available that allows simulations to faithfully reproduce the sample features, and that minimizes the computing time in structure refinements. However, attention is not always paid to this point and molecular models coming from general force-fields are frequently used to undertake many of the analyses. We propose in this work to use a Bayesian scheme to fit the experimental data and produce reliable molecular models that can be used as the starting point of any simulation or refinement. The algorithm behind the proposed method is based on a Markov chain Monte Carlo procedure, as many other refinement programs such as reverse Monte Carlo or empirical potential structure refinement.

Epicrania fugax: características clínicas de una serie de 18 pacientes / Epicrania fugax: the clinical characteristics of a series of 18 patients

Introducción. La epicrania fugax es una entidad de reciente descripción, consistente en breves paroxismos dolorosos iniciados en regiones cefálicas posteriores, con irradiación hacia ojo, nariz o sien ipsilaterales. Objetivo. Presentar 18 casos de epicrania fugax de una consulta monográfica de cefaleas de un hospital terciario y analizar sus características demográficas y clínicas, así como la indicación y respuesta al tratamiento profiláctico. Pacientes y métodos. Entre marzo de 2008, momento en el que se describe la epicrania fugax y marzo de 2011, 18 pacientes (12 mujeres y 6 hombres), de entre 1.210 atendidos en dicha consulta (1,48%), recibieron dicho diagnóstico. Seis de estos casos se habían publicado con anterioridad. Resultados. Edad media al inicio de 42,5 ± 17,7 años (rango: 23-82 años). Presentaban paroxismos dolorosos iniciados en la región occipital (n = 11; 61,1%), parietal (n = 6; 33,3%) o parietooccipital (n = 1; 5,6%), e irradiados hacia el ojo (n = 12; 66,6%) o la sien (n = 6; 33,3%) ipsilaterales; todo el proceso duraba menos de 15 segundos. La mayoría describía su dolor como lancinante o punzante. En 10 casos (55,5%) persistía un dolor en la zona de origen de los paroxismos, que en 6 (33,3%) estaba circunscrito a una zona circular bien delimitada y reunía criterios de cefalea numular. En 12 casos (66,6%) se utilizó tratamiento profiláctico, sobre todo lamotrigina y gabapentina con respuesta variable. Conclusión. Pretendemos reforzar la propuesta de la epicrania fugax como un nuevo síndrome con un espectro clínico bien caracterizado. No parece una entidad excepcional, y su conocimiento dará lugar probablemente a la descripción de nuevas series. Con frecuencia es necesario tratamiento y, aunque se requiere mayor experiencia, la gabapentina y la lamotrigina tienen un papel prometedor (AU)

Introduction. Epicrania fugax is a recently reported condition consisting in brief painful paroxysms that begin in the posterior regions of the brain and irradiate towards the ipsilateral eye, nose or temple. Aims. To present 18 cases of epicrania fugax from a monographic headache centre in a tertiary hospital and to analyse their demographic and clinical features, as well as the indication and response to prophylactic treatment. Patients and methods. Between March 2008, when epicrania fugax was first reported, and March 2011, of a total of 1210 patients who were attended in that service (1.48%), 18 (12 females and 6 males) were diagnosed as suffering from this condition. Six of these cases had been published earlier. Results. The mean age at onset was 42.5 ± 17.7 years (range: 23-82 years). They presented painful paroxysms that began in the occipital (n = 11; 61.1%), parietal (n = 6; 33.3%) or parieto-occipital (n = 1; 5.6%) regions and irradiated towards the ipsilateral eye (n = 12; 66.6%) or temple (n = 6; 33.3%); the whole process lasted less than 15 seconds. Most of them described the pain as lancinating or stabbing. In 10 cases (55.5%) a pain remained in the area where the paroxysms began, which in 6 cases (33.3%) was limited to a well-defined circular area and met the criteria for classification as nummular headache. In 12 cases (66.6%), prophylactic treatment was used, above all lamotrigine and gabapentin, with varying results. Conclusion. Our aim is to back the proposal of epicrania fugax as a new syndrome with a well-defined clinical spectrum. It does not appear to be an exceptional condition and further knowledge about it will probably give rise to the description of new series. Treatment is often necessary and, although further information and experience are needed, gabapentin and lamotrigine both play a promising role (AU)

Rehabilitación cognitiva en un caso de alteraciones neuropsicológicas y funcionales por traumatismo craneoencefálico severo / Cognitive rehabilitation in a neuropsychological and functional impairments case by severe traumatic brain injury

Introducción: el traumatismo craneoencefálico es en la actualidad una de las principales causas de incapacidad en la población joven, debido a que las alteraciones físicas y/o cognitivas, ocasionadas por la lesión, limitan el desempeño en actividades laborales, académicas y sociales de la persona afectada. Las secuelas cognitivas de tipo atencional y mnésico interfieren en actividades de la vida diaria y requieren intervención a través de un programa de rehabilitación cognitiva. Caso clínico: paciente de sexo masculino, 24 años de edad, 11 años de escolaridad, sufre traumatismo craneoencefálico severo. Transcurrido el período agudo, al alta, presentó múltiples alteraciones cognitivas, con compromiso en las actividades cotidianas. Se planea e inicia programa de rehabilitación para déficit neuropsicológicos, utilizando estrategias de restitución y sustitución. La intervención se realiza por un año, tres sesiones por semana. Se realizó seguimiento neurológico y neuropsicológico antes, durante y después; se observó mejoría en los procesos cognitivos y en la funcionalidad del paciente durante la rehabilitación. Conclusiones: la rehabilitación cognitiva es actualmente una herramienta terapéutica útil en el tratamiento del paciente con lesión cerebral, ya que puede ser efectiva más allá de la recuperación espontánea, en tanto mejorara procesos cognitivos y dificultades en actividades diarias secundarias a daño cerebral traumático.

Introduction: traumatic brain injury is in the present one of the most important causes of disability in young people, because cognitive and physical impairments limit patient`s work, academic and social activities performance. Cognitive consequences -specially mnesic, attentional and executive consequences- interfer in daily life activities. For this reason it is necessary to intervent altered areas through a cognitive rehabilitation program. Clinic case: male patient 24 years old, 11 years of education has severe traumatic brain injury. After acute period, when he go out from the hospital, he showed multiple cognitive impairments that affected daily life activities. A cognitive rehabilitation program is planned and started by using substitution and restitution strategies. Intervention is carried on along one year in three sessions per week. Neurological and neuropsychological monitoring was made before, during and alter the program; an improvement in cognitive processes and patient’s functionality was observed during rehabilitation. Conclusions: cognitive rehabilitation process can be more effective so far than spontaneous recovery as rehabilitation can improve cognitive processes of a patient with neuropsychological impairments and alterations in daily life activities, secondary to traumatic brain injury. Cognitive rehabilitation is in the presenta therapeutic skill useful for treatment of brain injured patient.

The role of N-linked carbohydrates in the antigenicity of Taenia solium metacestode glycoproteins of 12, 16 and 18 kD.

The glycoproteins of 12-28 kD from Taenia solium metacestodes provide a high specificity and sensitivity for the serological diagnosis of the central nervous system infection, neurocysticercosis. Their widespread use as antigens for routine serological assays will require their production in large and reproducible amounts. Prior to determining the ideal strategy to produce these antigens at a large scale, it is important to determine the contribution of the carbohydrates to the antigenicity of these molecules, given the uncertainty of reproducing saccharidic epitopes in recombinant expression systems. In this study we examined this issue. The chemical oxidation of the carbohydrates of the 12-28 kD glycoproteins with sodium metaperiodate, reduced the antigenicity of the molecules to variable extents, with the more notable changes being detected for the 18 and 28 kD antigens. This approach was complemented by purification of the 12, 16 and 18 kD antigens, followed by the enzymatic deglycosylation of their abundant N-linked oligosaccharides. Silver-stained SDS-PAGE analysis indicated that the three deglycosylated antigens now migrated as 7 kD products, suggesting a protein backbone with a similar size, but different extents of glycosylation. By Western blot, the antigenicity of these antigens was diminished. This was more notable for the 18 kD antigen, which is more heavily glycosylated than the 12 or 16 kD glycoproteins. These data suggest that the antigenicity of the glycoproteins of T. solium is due to a combination of carbohydrate and protein epitopes.

Characterisation of the carbohydrate components of Taenia solium metacestode glycoprotein antigens.

Human neurocysticercosis is caused by Taenia solium metacestodes. It usually affects the central nervous system of humans and can be confused with other brain pathologies. The Lens culinaris-binding glycoproteins from this parasite have been shown to be ideal targets for the development of a highly specific immunoassay for the diagnosis of neurocysticercosis. In the present study we characterised the carbohydrates associated with five antigenic glycoproteins of T. solium metacestodes in the range of 12-28 kilodaltons. Lectin-affinities and enzymatic deglycosylations suggested that each of the five antigens contain various glycoforms of asparagine-linked carbohydrates of the hybrid, complex and probably high mannose type. These carbohydrates accounted for at least 30-66% of the apparent molecular mass of the glycoconjugates. In contrast, there was no evidence for the presence of O-linked carbohydrates. Lectin affinity patterns suggested that the sugars are short and truncated in their biosynthetic route, and that some contain terminal galactose moieties. Elucidating the precise structure of the carbohydrates and establishing their role in antigenicity will be essential to design strategies to produce them in large and reproducible amounts for the development of improved immunoassays.

Micosis de los senos paranasales: descripción de seis casos / Paranasal sinus mycosis: description of 6 clinical cases

La afeccion micotica de los senos paranasales ha aumentado en los ultimos años, tanto bajo la forma de sinusitis alergica como de tipo invasivo y no invasivo, de tipo colonimnte. Se analizan en forma retrospectiva, seis casos de micosis en senos paranasales; dos de ellos con mucormicosis y los cuatro restantes con aspergillosis. Cinco de los pacientes fueron diagnosticados por examen directo y uno de ellos, por estudio histopatologico. Fue posible aislar el agente etiologico en dos casos, en uno de mucormicosis y en otro de aspergillosis. Los pacientes con mucormicosis presentaban una enfermedad de base y no fue posible salvarlos, a pesar del manejo quirurgico y del tratamiento con anfotericina B. Los cuatro casos de aspergillosis se observaron en pacientes inmunocompetentes; la sintomatologia era similar a una sinusitis cronica, pero en dos de ellos, el TAC mostro calcificaciones que hicieron sospechar la enfermedad. Los cuatro pacientes se recuperaron despues de cirugia endoscopica y de la administracion de itraconazole

Filariasis in Colombia: prevalence and distribution of Mansonella ozzardi and Mansonella (=Dipetalonema) perstans infections in the Comisaría del Guainía.

A survey was conducted to determine the prevalence and distribution of filarial infections among the inhabitants of Comisaría. Approximately 25% of the 604 individuals bled (Knott's sample) harbored microfilariae; more men (29.7%) were infected than women (23.7%); approximately 6% were infected with Mansonella (=Dipetalonema) perstans, 13% with Mansonella ozzardi, and 7% with both filariae. Mansonella ozzardi was more common in men than in women, and its prevalence increased with age in both sex groups; it was detected in most of the resident ethnic groups but was most common in the Puinave and the Curripaco Indians, and appeared to be distributed throughout the Comisaría. The prevalence of M. perstans was essentially the same in men as in women, and in age-groups from the 2nd to 4th decade, although its tendency to increase with age was not as marked as in M. ozzardi infections. Mansonella perstans appeared to be limited to the central and southern regions of the Comisaría, was found principally in the Curripaco Indians, and was detected in settlements situated within the drainage of both the Río Orinoco and the upper Río Negro. Approximately 9% of the white settlers (colonos) harbored M. ozzardi, and 5% M. perstans. These results indicate that both M. perstans and M. ozzardi are endemic in the Comisaría del Guainía, and suggest that the focus of M. perstans may extend further into the South American continent along the Río Negro and its tributaries.