Estandarización de la técnica Dot-ELISA para la detección de anticuerpos anti-Trypanosoma cruzi y su comparación con ELISA y Western blot

Introduction

Chagas disease is considered endemic of Latin America. Because of migration of people from this region to non-endemic areas, such as the United States, Canada and Europe, it has become a major health problem. There are parasitology and serology tests for its diagnosis, but only the latter are useful during the chronic phase. Most of these tests require expensive equipment, which make them also inaccessible for laboratories in endemic areas. In the present work we standardize Dot-ELISA as a diagnostic test for Trypanosoma cruzi infection, since it is an easy, inexpensive and an accessible test.

Methods

A total of 360 samples were tested: 96 sera from Chagas patients and 153 from healthy people; 40 blood samples spots collected and eluted from filter paper were also tested, as well as 71 serum samples of patients with non-related infections. Sensitivity, specificity and kappa index of Dot-ELISA test were calculated, in order to determine a correlation value of this technique compared to ELISA and Western blot that are already being used for diagnosis.

Results

Dot-ELISA obtained 97% sensitivity and 89% specificity, since it showed cross-reaction mainly with Leishmania spp., and a kappa index of 0,79.

Conclusions

Dot-ELISA results correlate well with other tests that are already being used for diagnosis of Chagas disease. As it is easy and inexpensive, it may be useful as an additional diagnostic test or for field studies.     

Cribado de Chagas en mujeres gestantes latinoamericanas. Experiencia en el Poniente Almeriense

Introduction

The transmission of Chagas disease is a public health problem in non-endemic countries.

Methods

Chagas screening was performed by two serological tests in pregnant women from endemic areas for 4 years.

Results

We studied 261 pregnant women from 13 Latin American countries, making a confirmatory diagnosis (two positive tests) in 4 cases. There was no case of vertical transmission.

Conclusion

Although Chagas disease has a low prevalence in the province of Almeria, the screening is necessary for the detection and treatment of infants with the disease.     

Free-roaming Kissing Bugs,Vectors of Chagas Disease,Feed Often on Humans in the Southwest

Background

Kissing bugs, vectors of Trypanosoma cruzi, the parasite that causes Chagas disease, are common in the desert Southwest. After a dispersal flight in summer, adult kissing bugs occasionally gain access to houses where they remain feeding on humans and pets. How often wild, free-roaming kissing bugs feed on humans outside their homes has not been studied. This is important because contact of kissing bugs with humans is one means of gauging the risk for acquisition of Chagas disease.

Methods

We captured kissing bugs in a zoological park near Tucson, Arizona, where many potential vertebrate hosts are on display, as well as being visited by more than 300,000 humans annually. Cloacal contents of the bugs were investigated for sources of blood meals and infection with T. cruzi.

Results

Eight of 134 captured bugs were randomly selected and investigated. All 8 (100%) had human blood in their cloacae, and 7 of 8 (88%) had fed on various vertebrates on display or feral in the park. Three bugs (38%) were infected with T. cruzi. Three specimens of the largest species of kissing bug in the United States (Triatoma recurva) were captured in a cave and walking on a road; 2 of 3 (67%) had fed on humans. No T. recurva harbored T. cruzi.

Conclusions

This study establishes that free-roaming kissing bugs, given the opportunity, frequently feed on humans outside the confines of their homes in the desert Southwest and that some harbored T. cruzi. This could represent a hitherto unrecognized potential for transmission of Chagas disease in the United States.     

Comparación entre técnicas inmunológicas y moleculares para el diagnóstico de la enfermedad de Chagas

Introduction

Chagas disease is caused by the parasite Trypanosoma cruzi. The disease involves an acute and chronic phases. The diagnosis has limitations, both in parasitological and immunological techniques. Molecular assays are an alternative, but these must be evaluated to determine its diagnostic usefulness. The aim of this study was to compare the effectiveness of immunological techniques with molecular assays in the diagnosis of Chagas disease in its different phases.

Methods

The immunological techniques used were ELISA, HAI and IFI and the molecular techniques used were PCR for amplification of kinetoplast minicircles, and satellite DNA of T. cruzi. Thirty-nine blood samples from patients in the acute phase of Chagas disease, and 42 samples from patients in the chronic phase were evaluated. In addition, 20 samples from healthy individuals and 10 patients with other diseases were also studied.

Results

With immunological techniques were positive, 69.2% of samples from patients in the acute phase, while in the chronic phase were positive 95.2%. Using molecular techniques 79.5% of samples from patients in the acute phase were positive, while 23.8% of the samples from patients in the chronic phase were positive. None of the samples from healthy individuals was positive for any technique, while two samples from patients with other diseases were positive by the immunological assays.

Conclusions

The diagnostic efficacy of molecular techniques is high in the acute phase of Chagas disease, while in the chronic phase the immunological techniques are more effective.     

Valoración de anticuerpos con reactividad cruzada patógeno-huésped en pacientes con diferentes estadios de cardiopatía chagásica crónica

Introduction and objectives

Trypanosoma cruzi infection has been shown to induce humoral autoimmune responses against host antigens tissues. Particularly, antibodies cross-reacting with myocardial antigens may play a role in the development of the severe forms of chronic Chagas disease. The aim of this study was to determine the association between clinical stage of the disease and the presence of autoantibodies in patients with chronic Chagasic disease.

Methods

We performed a cross-sectional study in T. cruzi-seropositive patients divided into 3 groups according to the classic classification of chronic Chagas heart of Storino et al. All participants underwent complete clinical examination and their sera were used to measure autoantibody levels.

Results

All patients had detectable levels of anti-p2β and anti-B13 autoantibodies but none had anti-Na-K-ATPase antibodies. No association was observed between electrocardiographic conduction disturbances and autoantibody levels. Patients with chronic Chagas disease stage III had the highest levels of anti-B13 antibodies and a high risk of mortality score, showing a clear association between disease stage and this score.

Conclusions

Anti-B13 antibodies were significantly higher in chronic Chagas disease stage III patients, suggesting that these antibodies may be involved in disease progression and that they might be a useful marker of poor prognosis in terms of heart compromise. Our results also reveal an important correlation between the level of anti-B13 autoantibodies and symptomatic heart failure and/or dilated cardiomyopathy.Full English text available from:www.revespcardiol.org/en     

Trypanosoma cruzi strains cause different myocarditis patterns in infected mice

Aims

Chagas disease pathology is dependent on the infecting Trypanosoma cruzi strain. However, the relationship between the extent and type of myocarditis caused by different T. cruzi strains in the acute and chronic phases of infection has not been studied in detail. To address this, we infected mice with three genetically distant T. cruzi strains as well as infected in vitro different cell types.

Methods and Results

Parasitemia was detected in mice infected with the Y and VFRA strains, but not with the Sc43 strain; however, only the Y strain was lethal. When infected with VFRA, mice showed higher inflammation and parasitism in the heart than with Sc43 strain. Y and VFRA caused homogeneous pancarditis with inflammatory infiltrates along the epicardium, whereas Sc43 caused inflammation preferentially in the auricles in association with intracellular parasite localization. We observed intramyocardic perivasculitis in mice infected with the VFRA and Y strains, but not with Sc43, during the acute phase, which suggests that endothelial cells may be involved in heart colonization by these more virulent strains. In in vitro infection assays, the Y strain had the highest parasite–cell ratio in epithelial, macrophage and endothelial cell lines, but Y and VFRA strains were higher than Sc43 in cardiomyocytes.

Conclusions

This study supports parasite variability as a cause for the diverse cardiac outcomes observed in Chagas disease, and suggests that endothelial cells could be involved in heart infection during the acute phase.     

La maladie de Behçet chez la femme

Purpose

Behçet's disease (BD) is a multisystemic inflammatory disease characterized, on the one hand, by the frequency of benign mucocutaneous and articular manifestations, and on the other hand by the severity of ocular, neurological, vascular and digestive manifestations which may threaten functional or vital prognosis. The male BD predominance is obvious in many retrospective studies and a few studies only have focused on BD in women.

Methods

In this study, we report the epidemiological, clinical, outcome and therapeutic data of a series of 71 female BD compared to a series of 111 male BD. This retrospective study was conducted in the internal medicine department of Monastir university hospital over a 19-year period (1990 to 2008), including all patients followed-up and treated for BD.

Results

The comparison of clinical manifestations of BD between men and women showed the predominance of erythema nodosum (P = 0.016), necrotic pseudofolliculitis (P = 0.001), and joint involvement (P = 0.009) in women, while genital ulcers (P = 0.039), ocular involvement (P = 0.003) and vascular (P = 0.002) involvement were more common in men.

Conclusion

Our results confirmed the results of previous studies regarding the benign nature of BD in women compared to men.     

Perfil serológico en gestantes extranjeras frente a VIH,VHB, VHC,virus de la rubéola, Toxoplasma gondii,Treponema pallidum, y Trypanosoma cruzi

Introduction

The increase in immigration is changing the prevalence of mother to child infectious diseases. Our aim is to determine the serological profile of foreign pregnant women against these infections.

Methods

A retrospective cross sectional study was performed in a tertiary hospital from Madrid between August 2007 and October 2008. The seroprevalence against HIV, HBV, HCV, rubeola, T. gondii, T. pallidum and T. cruzi was determined in every pregnant immigrant, as well as in a representative group of Spanish pregnant women.

Results

A total of 2526 immigrant and 157 Spanish pregnant women were studied. None of the Spanish and 0.5% of the foreigners showed antibodies against HIV; 18.9% of them were Sub-Saharan women. Antigen HBs was detected in 2% of the immigrant women and in 1.1% of the Spanish women. Asian women had the highest rate of type B Hepatitis (10.9%). There was 0.9% of type C Hepatitis among the immigrants and 1% among the Spanish. Within the cases with RPR ≥ 1/8, 1.6% were immigrants, most of whom were Latin American. Thirty-one per cent of the immigrants showed antibodies against T. gondii (37.5% from Central America, 2.5% from the Far East). More than 95% of the Spanish women had antibodies against Rubella, this being lower in the rest of the areas (75.5% in Sub-Saharan Africa). T. cruzi infection was detected in 12.1% of the Bolivian women studied.

Conclusion

The prevalence of mother-to-child transmitted infections depends on the origin of pregnant women. Knowledge of these differences may lead to improved control these diseases.     

Evaluación inicial del programa de prevención de la transmisión materno-infantil de la infección por el virus de la inmunodeficiencia humana en Guinea Ecuatorial

Background

The prevalence of human immunodeficiency virus (HIV)-infected pregnant women in Equatorial Guinea (EG) has been reported as 7.3%. In 2008 an updated version of the PMTCT protocol was accepted according to the current WHO guidelines. The aim of this study was to describe the characteristics and outcome of children exposed to HIV after the introduction of the protocol.

Methods

A retrospective review was conducted on the clinical characteristics of the infants born to HIV-infected mothers in the Hospital Regional de Bata and Primary Health Care Centre Maria Rafols in Bata (EG) between June 2008 and November 2011. The diagnosis of HIV infection in children was based on rapid serology tests.

Results

A total of 103 children were included, of which 47 were males. Fifty three patients (51%) completed the follow-up (51%). Fourteen children (26%) were diagnosed with HIV infection (11 presumptive diagnosis, 3 due to persistence of antibodies at 18 months). Six children (12%) died before a definitive diagnosis. Just over than half (52%) of mothers received antiretroviral therapy (ART) during pregnancy. The transmission rate in children whose mothers received ART was 16% (3/19), compared with 43% (10/23) in children whose mothers did not receive it. Only one child was infected (8%) when the mother received ART, and child received postnatal prophylaxis.

Conclusions

The PMTCT protocol compliance was still very low. Antiretroviral therapy in pregnant women decreased the rate of vertical transmission, but the rate still remains very high. Many children were lost to follow-up. Strategies to prevent loss to follow-up and methods for earlier virological diagnostic are needed.     

Oesophageal mucosal intercellular space diameter and reflux pattern in childhood erosive and non-erosive reflux disease

Background and aims

We sought to compare intercellular space diameter in children with non-erosive and erosive reflux disease, and a control group. We also aimed to characterize the reflux pattern in erosive and non-erosive reflux disease patients, and to explore the relationship between intercellular space diameter values and reflux parameters.

Methods

Twenty-four children with non-erosive reflux disease, 20 with erosive reflux disease, and 10 controls were prospectively studied. All patients and controls underwent upper endoscopy. Biopsies were taken at 2–3 cm above the Z-line, and intercellular space diameter was measured using transmission electron microscopy. Non-erosive and erosive reflux disease patients underwent impedance-pH monitoring.

Results

Mean intercellular space diameter values were significantly higher in both non-erosive (0.9 ± 0.2 μm) and erosive reflux disease (1 ± 0.2 μm) compared to controls (0.5 ± 0.2 μm, p < 0.01). No difference was found between the two patient groups. Acid exposure time, the number of acid, weakly acidic and weakly alkaline reflux events did not differ between the two patient groups. No difference was found in the mean intercellular space diameter between non-erosive reflux disease children with and without abnormal acid exposure time (1 ± 0.3 vs. 0.9 ± 0.2 μm). No correlation was found between any reflux parameter and intercellular space diameter values.

Conclusions

Dilated intercellular space diameter seems to be a useful and objective marker of oesophageal damage in paediatric gastro-oesophageal reflux disease, regardless of acid exposure. In childhood, different gastro-oesophageal reflux disease phenotypes cannot be discriminated on the basis of reflux pattern.     

Pratique médicale dans la prise en charge de l’hypertension artérielle comme facteur de risque rénal en pratique médicale générale,et en prévention primaire,chez l’enfant en milieu scolaire et la femme enceinte dans la région d’Annaba (Algérie)

Objective

To study medical practice in the management of hypertension as a factor in renal risk in general medical practice and primary prevention in children at school, and pregnant women under prenatal monitoring.

Method

The longitudinal study, observational over a year, focused on medical practice in schools, maternal health and medical practice among 100 physicians (general practitioner and specialist practitioner) in Annaba (Algeria).

Results

In children in schools, measurement of blood pressure is never done on the grounds because this gesture is considered unnecessary in 100% of cases. In pregnant women, the measurement of blood pressure is not performed in more than 26% of pregnant women because it is deemed unnecessary by the midwife in 89% of pregnant women and default material in 11% of they. In current medical practice, 69% of doctors routinely take blood pressure. For the rest, represented mainly by specialists, it is the patient who does not justify. Sixty-two percent of physicians, that is hypertension, above 140/90 mmHg, and 15% of physicians that is hypertension, above 145/95 mmHg. Among the physicians, 58.7% did not use urinary strip, either, because they think that this review should be done in a laboratory (64.8%), or because the urinary strip are not available at even consulting (35.2%).

Conclusion

Inadequacies in the coverage (care) of the HTA are real. Their effects on the progress of prevalence of the renal insufficiency chronic terminal treated are possibly important.     

Frecuencia del polimorfismo -262 C/T en el gen de la catalasa y lesión oxidativa en niños eslovacos con asma bronquial

Introduction

Bronchial asthma is a complex disease in which genetic factors, environmental factors and oxidative damage are responsible for the initiation and modulation of disease progression. If antioxidant mechanisms fail, reactive oxygen species damage the biomolecules followed by progression of the disease. Catalase is one of the most important endogenous enzymatic antioxidants. In the present study, we examined the hypothesis that increased oxidative damage and polymorphism in the CAT gene (-262 promoter region, C/T) are associated with childhood bronchial asthma.

Patients and methods

Genotyping of the polymorphisms in the CAT gene in healthy (249) and asthmatic children (248) was performed using polymerase chain reaction–restriction fragment length polymorphism. Markers of oxidative damage: content of sulfhydryl groups and thiobarbituric acid-reactive substances were determined by spectrophotometry in children.

Results

The TT genotype of catalase was more frequent among the asthmatic patients (22.6%) than in healthy children (4.8%) (odds ratio = 5.63; 95% confidence interval = 2.93–10.81, P < .001). The amount of sulfhydryl groups decreased significantly and conversely, the content of thiobarbituric acid-reactive substances increased significantly in bronchial asthma and in catalase TT genotype compared to other catalase genotypes of this gene.

Conclusions

These results suggest that catalase polymorphism might participate in development of bronchial asthma and in enhanced oxidative damage in asthmatic children. Genetic variation of enzymatic antioxidants may modulate disease risk.     

La pancréatite lupique : une série de six cas

Purpose

The occurrence of acute pancreatitis in systemic lupus erythematosus (SLE) is known but rare, and is exceptionally the presenting manifestation. Its pathogenesis is multifactorial, and it is difficult to separate what belongs to vasculitis, thrombotic phenomena in the context of an associated antiphospholipid syndrome, or iatrogenic complications. We report on six cases of lupus pancreatitis.

Methods

This is a retrospective monocenter study of 110 patients with SLE. The diagnosis of lupus pancreatitis was established after exclusion of other causes of pancreatitis.

Results

Five women and one man (5.4%) with a mean age of 36.3 years presented with lupus pancreatitis. In four patients the pancreatitis was concurrent with the diagnosis of SLE and it occurred later during an exacerbation of the disease in the two remaining patients. In all patients, pancreatic manifestations were associated with other organ involvement. Clinical manifestations were: abdominal pain (n = 6), vomiting (n = 3), and fever (n = 3). Elevated pancreatic enzyme was noted in all cases. All patients were treated by high doses of glucocorticoids. The outcome was favorable in five patients, and one patient died.

Conclusion

Pancreatitis may be the presenting manifestation of SLE. Its pathogenesis is often multifactorial. The outcome is usually favorable with corticosteroids.     

Maternal serum and fetal cord blood irisin levels in gestational diabetes mellitus

Aim

To investigate the relationship between maternal and cord blood irisin in gestational diabetes mellitus (GDM).

Methods

Twenty women with GDM and 20 pregnant women with uncomplicated pregnancies were recruited for this case–control study. Maternal serum irisin and cord blood irisin levels were measured by enzyme-linked immunosorbent assay kit at the time of birth. The association of maternal serum and cord blood irisin levels with metabolic parameters was analyzed.

Results

Women with GDM had significantly lower mean serum irisin levels compared to control group (258.3 ± 127.9 vs. 393 ± 178.9 ng/ml, p < 0.05). Mean cord blood irisin levels for GDM and control groups were not significantly different (357.2 ± 248.0 vs. 333.2 ± 173.4 ng/ml, p > 0.05). No significant differences were found in terms of maternal age, gestational week at birth, BMI at birth, birth weight, neonatal height, systolic and diastolic blood pressure between the groups as well (p > 0.05). Serum irisin level was negatively correlated with BMI at birth and HOMA-IR (r = −0.401, p = 0.010; r = −0.395, p = 0.012, respectively). No correlations between irisin levels and others parameters were found in both groups.

Conclusions

Maternal serum irisin levels of patients with GDM are significantly lower compared with non-GDM controls. However, no significant difference was found between cord blood irisin levels of patients with GDM and healthy pregnant women.     

Sclérites,aspects cliniques, étiologiques et thérapeutiques : à propos d’une série de 32 observations

Purpose

To report on the various clinical presentations, etiological diagnosis, prognosis and treatment of patients with scleritis evaluated at a tertiary care eye center.

Methods

Retrospective, monocentric study on a series of 32 patients in a tertiary center.

Results

The mean age of included patients with scleritis was 46.8 years (range, 22 to 77 years). Nineteen patients were women and 13 were men. Twenty-six patients (81%) had anterior scleritis (15 nodular, 8 diffuse and 3 necrotizing), six (19%) had posterior scleritis. Unilateral inflammation was present in 24 patients (75%). Twelve out of the 32 patients (37.5%) had an underlying systemic disease: granulomatosis with polyangiitis (n = 3), Behçet's disease (n = 2), unspecified inflammatory arthritis (n = 2), psoriatic arthritis (n = 1), ankylosing spondylitis (n = 1), sarcoidosis (n = 1), Cogan's syndrome (n = 1) and ulcerative colitis (n = 1). Six patients (18.8%) were suspected of having infectious disease with herpes virus: clinical context and positive treatment response with oral valacyclovir. Systemic agents and topical agents were required in 28 patients (87.5%). The first line therapy was mainly oral non-steroidal anti-inflammatory drugs in 15 patients (47%) and oral corticosteroids in 8 (25%). Immunosuppressive drugs were required in 6 patients. The mean follow-up was 16.3 months. Six patients (19%) had a decrease in visual acuity.

Conclusion

The number of systemic disease in our series is similar to the main series in the literature. Treatment with valaciclovir might be effective in patients with suspected herpes simplex scleritis.     

Rangos de referencia en niños preescolares mexicanos con el empleo de la técnica de oscilación forzada

Introduction

Recently, multi-ethnic reference ranges for spirometry have been created for use worldwide. In comparison, forced oscillation technique (FOT) reference values are limited to specific equipment and study populations, with current FOT reference ranges created in a Caucasian population. We aimed to develop FOT reference ranges for preschool-aged Mexican children and to compare these with current FOT reference ranges.

Patients and methods

Respiratory resistance (Rrs) and reactance (Xrs) was measured in healthy Mexican children three to five years of age using commercial FOT equipment. The relationship between height and Rrs and Xrs was determined using regression analyses, taking into account age, weight, sex, and exposure to tobacco smoke. Reference equations were calculated for the Mexican children and Z-scores determined for Rrs and Xrs at 6 and 8 Hz. A paired t-test assessed the difference in Z-scores between the Australian reference values and those created for the Mexican cohort.

Results

FOT was successfully measured in 584 children. Height was a significant predictor of Rrs and Xrs at 6 and 8 Hz (P < .05). Z-scores calculated using the Australian reference equations overestimated lung function in Mexican children for both Rrs and Xrs at 6 and 8 Hz (P < .001).

Conclusion

The development of FOT reference ranges specific to Mexican preschool-aged children will allow for the correct interpretation of FOT measurements. This study also showed that current FOT reference ranges overestimate lung function in Mexican children. Highlighting, the importance of using ethnic appropriate reference ranges for interpreting lung function.