Errores de registro en las mediciones de presión arterial realizadas en dos centros de atención primaria de la salud de la ciudad de Salta, Argentina / Innacuracy in records of blood pressure measurements in two primary health centers of Salta City, Argentine

RESUMEN Introducción: El diagnóstico de hipertensión arterial (HTA) se realiza por la toma de la presión arterial (PA) en el consultorio médico (C) o en enfermería (E). Es frecuente aproximar los valores obtenidos a múltiplos de 10. Esto puede causar imprecisiones en el diagnóstico y el control de la HTA. Objetivo: Determinar cuántos registros de PA terminaban en cero en las mediciones realizadas en E y en C en dos centros de atención primaria de la salud de la ciudad de Salta. Material y métodos: Se efectuó un estudio descriptivo, transversal, de febrero a diciembre de 2018. Se utilizó un tensiómetro digital. A cada paciente se le midió la PA dos veces, primero en E y luego en C. Se utilizaron las pruebas de Chi2 y de Wilcoxon. Resultados: Se estudiaron 311 individuos, 60,77% mujeres. Edad media: 56,15 ± 13,8 años. Los registros terminados en cero tuvieron las siguientes frecuencias: PA sistólica en E: 36%; PA diastólica en E: 40,51%; PA sistólica en C: 11,58%; PA diastólica en C: 7,72% (p <0,0001). La PA sistólica y diastólica terminaron simultáneamente en cero en el 30,87% de los casos cuando se midieron en E y en el 0,64% de los casos cuando se midieron en C (p <0,0001). Conclusiones: La PA sistólica y la PA diastólica terminaron en cero con una frecuencia 3 y 5 veces mayor en E que en C, respectivamente, y la frecuencia de registros de PA sistólica y diastólica coincidentemente terminados en cero fue 48 veces mayor en E que en C. Estos resultados refuerzan la necesidad de una capacitación permanente para mejorar el registro en la medición de la PA.

ABSTRACT Background: The diagnosis of hypertension is established by blood pressure (BP) measurements in doctor (DO) or nursing offices (NO). Frecuently BP measurements are recorded as multiples of ten. This can lead to inaccuracy in diagnosis and control of hypertension. Objetive: To determine the percentage of BP measurements ending in zero in DO and NO, in the records of two health primary centers of Salta city. Methods: Observational study from february to december of 2018. Digital blood pressure monitor was used. Each patient BP was measured twice, first in NO and then in DO. Data were analyzed using the Chi2 and Wilcoxon tests. Results: 311 indivuals were enrolled, 60,77% were female. The average age was 56,15 ± 13,8 years. In NO the systolic BP and diastolic BP ending in zero were 36 and 40,51% respectively, while in DO were 11,58 and 7,72% (p <0,0001). The systolic BP and diastolic BP ending in zero simultaneously in NO was 30,87%, while in DO was 0,64% (p <0,0001). Conclusions: The systolic BP and the diastolic BP records ending in zero were three and five times more frequent in NO than in DO. The systolic BP and diastolic BP ending in zero simultaneously in NO were forty-eight times more frequent than in DO. These results reinforce the need of health personnel permanent training to improve precision for measuring and recording BP in medical centers.

Genetic and clinical characterization of canine leishmaniasis caused by Leishmania (Leishmania) infantum in northeastern Argentina.

Leishmaniases comprise zoonotic diseases caused by protozoan flagellates of the Leishmania genus. They are endemic to South America, and the visceral form has been recently reported in Argentina. Dogs can play different roles in the Leishmania transmission cycles, depending mainly on the species of parasite involved. Here we focused on the clinical characterization of canine leishmaniasis (CanL) in Northeast Argentina and on the molecular typing of its etiological agent. The nested polymerase chain reaction and sequence analysis of the Leishmania cytochrome b (cyt b) gene was performed on DNA templates purified from lymph nodes, bone marrow or spleen aspirates obtained from 48 dogs previously diagnosed by the observation of Leishmania amastigotes on smears from these aspirates. Their clinical and epidemiological data were also recorded. Systemic abnormalities were observed in 46 subjects (95.8%), most frequently lymphadenopathy, and emaciation (89.6 and 75%). Furthermore, 87% also presented tegumentary abnormalities, such as alopecia (54.2%) or secondary skin lesions (47.9%), among others. Twenty three dogs were positive for cyt b amplification. The sequence analysis showed the presence of two genotypes, LiA1 and LiA2, assigned to Leishmania (Leishmania) infantum, with 99.9 and 100% homology with the reference strain MHOM/TN/80/IPT1 respectively. LiA1 was identified in 18 cases (78.3%) and LiA2 in five (21.7%). Two cyt b variants of L. (L.) infantum were incriminated as the causative agents of CanL cases from three cities: Posadas, Garupá, and Ituzaingó. All three cities are located in the northeastern area of the country, where these parasites seem to be spreading in urban areas.

Visceral Leishmaniasis Caused by Leishmania infantum in Salta, Argentina: Possible Reservoirs and Vectors.

Cases of human visceral leishmaniasis (HVL) were not recorded until recently in the Chaco region of northwestern Argentina. Dogs were surveyed at the sites of infection of two HVL index cases in the Chaco region of Salta province. Canine cases (CanL) were diagnosed by two parasitological methods, two molecular methods targeting mini- and maxicircle DNA, and immunochromatographic dipstick. Among 77 dogs studied, 10 (13%) were found infected with Leishmania spp. In seven dogs and two humans, the infecting species was typed as Leishmania (Leishmania) infantum. The same genotype was detected in the human and two of the CanL. Although several diagnostic methods displayed weak or moderate agreement, the concordance values for serology versus maxicircle PCR were very good (Kappa index = 0.84). Sandflies captured in the area were identified as Lutzomyia migonei and Lu. cortelezzii/Lu. sallesi (cortelezzii complex). The focal appearance of leishmaniasis in dogs and humans in a sylvatic region and its relatively low prevalence of infection suggests that L. (L.) infantum transmission to dogs and humans may, in this region, stem from sylvatic reservoirs.

Biological Control of the Chagas Disease Vector Triatoma infestans with the Entomopathogenic Fungus Beauveria bassiana Combined with an Aggregation Cue: Field, Laboratory and Mathematical Modeling Assessment.

BACKGROUND: Current Chagas disease vector control strategies, based on chemical insecticide spraying, are growingly threatened by the emergence of pyrethroid-resistant Triatoma infestans populations in the Gran Chaco region of South America. METHODOLOGY AND FINDINGS: We have already shown that the entomopathogenic fungus Beauveria bassiana has the ability to breach the insect cuticle and is effective both against pyrethroid-susceptible and pyrethroid-resistant T. infestans, in laboratory as well as field assays. It is also known that T. infestans cuticle lipids play a major role as contact aggregation pheromones. We estimated the effectiveness of pheromone-based infection boxes containing B. bassiana spores to kill indoor bugs, and its effect on the vector population dynamics. Laboratory assays were performed to estimate the effect of fungal infection on female reproductive parameters. The effect of insect exuviae as an aggregation signal in the performance of the infection boxes was estimated both in the laboratory and in the field. We developed a stage-specific matrix model of T. infestans to describe the fungal infection effects on insect population dynamics, and to analyze the performance of the biopesticide device in vector biological control. CONCLUSIONS: The pheromone-containing infective box is a promising new tool against indoor populations of this Chagas disease vector, with the number of boxes per house being the main driver of the reduction of the total domestic bug population. This ecologically safe approach is the first proven alternative to chemical insecticides in the control of T. infestans. The advantageous reduction in vector population by delayed-action fungal biopesticides in a contained environment is here shown supported by mathematical modeling.

In vivo antileishmanial efficacy of miltefosine against Leishmania (Leishmania) amazonensis.

Leishmaniasis, a disease caused by parasites of the Leishmania genus, constitutes a significant health and social problem in many countries and is increasing worldwide. The conventional treatment, meglumine antimoniate (MA), presents numerous disadvantages, including invasiveness, toxicity, and frequent therapeutic failure, justifying the attempts at finding alternatives to the first-line therapy. We have studied the comparative long-term efficacy of MA against miltefosine (MF) in Leishmania infection in experimental mice. The criteria for efficacy evaluation were footpad lesion size, anti-Leishmania antibodies level, histopathology of the site of inoculation (right footpad, RFP), splenic index (SI), and the presence of parasites in RFP, spleen, and liver, determined by polymerase chain reaction (PCR). Swiss mice, infected with Leishmania (Leishmania) amazonensis were treated, at different time points (5 and 40 days after infection) with either MA or MF. The efficacy of MF was better than that of MA for inhibiting lesions and for reducing tissue damage and presence/load of amastigotes in spleen and liver. Moreover, early administration of MF produced a clear reduction in splenomegaly and was equal in reducing antibody titles in comparison with MA. Our results demonstrated that MF is an effective and safe therapeutic alternative for leishmaniasis by L. (L.) amazonensis and is more efficacious than MA.

A monoallelic deletion of the TcCRT gene increases the attenuation of a cultured Trypanosoma cruzi strain, protecting against an in vivo virulent challenge.

Trypanosoma cruzi calreticulin (TcCRT) is a virulence factor that binds complement C1, thus inhibiting the activation of the classical complement pathway and generating pro-phagocytic signals that increase parasite infectivity. In a previous work, we characterized a clonal cell line lacking one TcCRT allele (TcCRT+/-) and another overexpressing it (TcCRT+), both derived from the attenuated TCC T. cruzi strain. The TcCRT+/- mutant was highly susceptible to killing by the complement machinery and presented a remarkable reduced propagation and differentiation rate both in vitro and in vivo. In this report, we have extended these studies to assess, in a mouse model of disease, the virulence, immunogenicity and safety of the mutant as an experimental vaccine. Balb/c mice were inoculated with TcCRT+/- parasites and followed-up during a 6-month period. Mutant parasites were not detected by sensitive techniques, even after mice immune suppression. Total anti-T. cruzi IgG levels were undetectable in TcCRT+/- inoculated mice and the genetic alteration was stable after long-term infection and it did not revert back to wild type form. Most importantly, immunization with TcCRT+/- parasites induces a highly protective response after challenge with a virulent T. cruzi strain, as evidenced by lower parasite density, mortality, spleen index and tissue inflammatory response. TcCRT+/- clones are restricted in two important properties conferred by TcCRT and indirectly by C1q: their ability to evade the host immune response and their virulence. Therefore, deletion of one copy of the TcCRT gene in the attenuated TCC strain generated a safe and irreversibly gene-deleted live attenuated parasite with high immunoprotective properties. Our results also contribute to endorse the important role of TcCRT as a T. cruzi virulence factor.

Control of pyrethroid-resistant Chagas disease vectors with entomopathogenic fungi.

BACKGROUND: Triatoma infestans-mediated transmission of Tripanosoma cruzi, the causative agent of Chagas disease, remains as a major health issue in southern South America. Key factors of T. infestans prevalence in specific areas of the geographic Gran Chaco region-which extends through northern Argentina, Bolivia, and Paraguay-are both recurrent reinfestations after insecticide spraying and emerging pyrethroid-resistance over the past ten years. Among alternative control tools, the pathogenicity of entomopathogenic fungi against triatomines is already known; furthermore, these fungi have the ability to fully degrade hydrocarbons from T. infestans cuticle and to utilize them as fuel and for incorporation into cellular components. METHODOLOGY AND FINDINGS: Here we provide evidence of resistance-related cuticle differences; capillary gas chromatography coupled to mass spectrometry analyses revealed that pyrethroid-resistant bugs have significantly larger amounts of surface hydrocarbons, peaking 56.2+/-6.4% higher than susceptible specimens. Also, a thicker cuticle was detected by scanning electron microscopy (32.1+/-5.9 microm and 17.8+/-5.4 microm for pyrethroid-resistant and pyrethroid-susceptible, respectively). In laboratory bioassays, we showed that the virulence of the entomopathogenic fungi Beauveria bassiana against T. infestans was significantly enhanced after fungal adaptation to grow on a medium containing insect-like hydrocarbons as the carbon source, regardless of bug susceptibility to pyrethroids. We designed an attraction-infection trap based on manipulating T. infestans behavior in order to facilitate close contact with B. bassiana. Field assays performed in rural village houses infested with pyrethroid-resistant insects showed 52.4% bug mortality. Using available mathematical models, we predicted that further fungal applications could eventually halt infection transmission. CONCLUSIONS: This low cost, low tech, ecologically friendly methodology could help in controlling the spread of pyrethroid-resistant bugs.

Impairment of infectivity and immunoprotective effect of a LYT1 null mutant of Trypanosoma cruzi.

Trypanosoma cruzi infection of host cells is a complex process in which many proteins participate but only a few of these proteins have been identified experimentally. One parasite factor likely to be involved is the protein product of LYT1, a single-copy gene cloned, sequenced, and characterized by Manning-Cela et al. (Infect. Immun. 69:3916-3923, 2001). This gene was potentially associated with infectivity, since the deletion of both LYT1 alleles in the CL Brenner strain (the wild type [WT]) resulted in a null mutant T. cruzi clone (L16) that shows an attenuated phenotype in cell culture models. The aim of this work was to characterize the infective behavior of L16 in the insect vector and murine models. The infection of adult Swiss mice with 10(3) trypomastigotes of both clones revealed a significant reduction in infective behavior of L16, as shown by direct parasitemia, spleen index, and quantitation of tissue parasite burden, suggesting the loss of virulence in the null mutant clone. Although L16 blood counts were almost undetectable, blood-based PCRs indicated the presence of latent and persistent infection during all of the study period and epimastigotes were reisolated from hemocultures until 12 months postinfection. Nevertheless, virulence was not restored in L16 by serial passages in mice, and reisolated parasites lacking the LYT1 gene and bearing the antibiotic resistance genes revealed the stability of the genetic manipulation. Histopathological studies showed a strong diminution in the muscle inflammatory response triggered by L16 compared to that triggered by the WT group, consistent with a lower tissue parasite load. A strong protection against a virulent challenge in both L16- and WT-infected mice was observed; however, the immunizing infection by the genetically modified parasite was highly attenuated.

Multilocus enzyme electrophoresis analysis of Trypanosoma cruzi isolates from a geographically restricted endemic area for Chagas' disease in Argentina.

A set of 65 Trypanosoma cruzi stocks from dogs, opossums, insect vectors and humans was isolated in a geographically restricted endemic area for Chagas' disease in Argentina and was analysed by multilocus enzyme electrophoresis for 15 loci. The results show that at least five multilocus genotypes (clonets) circulate in the study area, one belonging to T. cruzi IIe, one to T. cruzi IId and three clonets belonging to T. cruzi I; and they confirm the presence of these lineages in the country. The three clonets attributed to T. cruzi I were identical to each other for all loci except for Sod-2, where three different patterns were identified. These patterns suggest the presence of two homozygous genotypes and one heterozygous genotype. Our results also suggest association of clonet IIe with dogs, clonet IId with humans and the three T. cruzi I clonets with Didelphis albiventris. On the other hand, there was no significant association between Triatoma infestans and any particular clonet circulating in the area. These findings are consistent with the hypothesis of natural selection, from mixed populations of T. cruzi in vectors, toward more restricted populations in mammals. The epidemiological implications of the possible selection of different clonets by different mammal hosts and the significance of two homozygous genotypes and one heterozygous genotype for the Sod-2 locus are discussed.