Parasitological versus molecular diagnosis of strongyloidiasis in serial stool samples: how many?

Strongyloidiasis is usually an asymptomatic disease in immunocompetent patients, caused by Strongyloides stercoralis. However, in immunocompromised patients it can produce a severe clinical profile. Therefore, a correct diagnosis is necessary in these cases and in those chronic asymptomatic patients. The low sensitivity of classical parasitological techniques requires the analysis of multiple serial stool samples. Molecular diagnostic techniques represent an improvement in the detection of the parasite. The objective of this study was to evaluate the minimum number of samples necessary to achieve maximum sensitivity by real-time polymerase chain reaction (PCR). A total of 116 stool samples from 39 patients were analysed by direct microscopic observation, agar culture, Harada-Mori and real-time PCR, in one, two, three and four or more consecutive samples. After two serial samples, 6 out of 39 patients were positive by parasitological and molecular techniques, while 16 of them were real-time PCR positive, and all the patients detected by parasitology were also detected by the molecular technique, reaching 100.00% sensitivity versus 83.00% when analysing a single sample. These data also reflect apparently low specificity (51.52%) and positive predictive value (PPV) (27.27 %) values, due to the high number of cases detected by real-time PCR and not by parasitological techniques. These cases were confirmed as true positives when analysing three, four or more samples from the same patient. In conclusion, the application of molecular techniques decreases the number of serial stool samples necessary to give a diagnosis with the maximum sensitivity.

Peritoneal tuberculosis due to Mycobacterium caprae.

The incidence of tuberculosis in humans due to Mycobacterium caprae is very low and is almost confined to Europe. We report a case of a previously healthy 41-year-old Moroccan with a 6 month history of abdominal pain, weight loss, fatigue and diarrhea. A diagnosis of peritoneal tuberculosis due to M. caprae was made.

[Airway pressure monitoring by the continuous flow method in paediatric thoracoscopic surgery. A study in an animal model]. / Monitorización de las presiones de la vía aérea con la modalidad de flujo continuo en cirugía toracoscópica pediátrica. Estudio en modelo animal.

OBJECTIVE: To compare the airway pressures obtained before the endotracheal tube with the intratracheal ones in the continuous flow ventilation mode, in thoracoscopic surgery for one lung ventilation, in a paediatric model in animals. MATERIAL AND METHODS: A simple prospective observational study was conducted. Ten Large White pigs weighing 4.6 ± 0.8 kg were used. The animals were ventilated in neonatal mode (continuous flow) with a Temel Supra ventilator. Using tracheotomy, we completely sealed the respiratory system in order to use tubes without special endotracheal cuffs, which would enable tracheal pressures to be registered without interfering with ventilation. Collapse of the right lung was performed by videothoracoscopy and was maintained for 120 min. The variables were measured at 10 time periods: start and 5 min with both lungs, after collapse at 5, 15, 30, 60, 90 and 120 min, and 5 and 15 min after lung re-expansion. We recorded the baseline, peak, plateau and positive end expiratory pressure in the mouth of the animal and intratracheal. RESULTS: The mean peak pressure in the mouth of the animal in one lung ventilation was 23.38 mmHg and tracheal ventilation was 21.24 mmHg, while the mean plateau pressure in the mouth of the animal in one lung ventilation it was 21.88 mmHg and tracheal was 21.39 mmHg, respectively, with significant differences in all of them (P<.05). We found statistically significant differences (P<.05) for peak and plateau pressure on comparing the record in the animal mouth with the tracheal record. The difference in absolute value was higher for the peak pressure record. CONCLUSIONS: The pressure parameters recorded in the animal mouth were acceptable for surgery, with a suitable respiratory and haemodynamic stability being maintained. We can state that the continuous flow mode according to the pressures study may be suitable for this type of surgery, and that the mouth of the animal (patient) record for the peak pressure does not reflect what really happens in the alveoli, but we can give a suitable clinical estimate for the plateau pressure.

[Update on the current role of plasma cholinesterase]. / Papel de las colinesterasas plasmáticas. Actualización.

The antagonism of steroidal nondepolarizing neuromuscular blockers (NDMBs) moved forward recently with the introduction of sugammadex, the only drug able to immediately reverse the effects of curarization produced by NDMBs. This advance has necessitated reflection on the future role of pseudocholinesterase. In spite of the side effects of succinylcholine and published opinions on its use, this NDMB continues to be used in clinical anesthesia. Pseudocholinesterase is mainly found in the liver, plasma, and nervous system. The enzyme is synthesized in the liver in greater amounts than required although certain conditions lead to deficiency, which is usually asymptomatic. The only clinical expression is the apnea which develops after administration of succinycholine because this NDMB cannot be metabolized. In some patients, slight reductions in the antagonism of succinylcholine lead to rising neuromuscular concentrations of the drug in accordance with the degree and duration of the blockade. We review the various forms of pseudocholinesterase deficiency, including a discussion of genetic variants, clinical manifestations, and management. In addition to discussing the diagnosis of this condition and the clinical implications, we highlight the importance of practice protocols and access to a referral laboratory if one is not available within the immediate hospital.

[Proposed experimental model to provide training in the management of anesthesia in liver transplantation]. / Propuesta de un programa de formación usando un modelo experimental para el manejo anestésico del trasplante hepático.

OBJECTIVE: To propose and evaluate the use of a porcine model for training in how to manage and improve the quality of anesthesia during liver transplantation. MATERIAL AND METHODS: Five trained anesthesiologists who had no previous experience in managing anesthesia during liver transplantation and who did not work in hospitals where the procedure was performed volunteered for the training course and evaluated it. Each trainee anesthetized 5 animals. Surgery was performed under total balanced anesthesia with monitoring of hemodynamics, ventilation, biochemistry, arterial blood gases, and coagulation. Previously set criteria were used to evaluate the trainees' skill in maintaining patient stability. Their work was assessed 7 times: at baseline, 15 minutes into the preanhepatic phase, at the end of the preanhepatic stage, 15 minutes into the anhepatic phase, at the end of the anhepatic phase, 15 minutes into the postanhepatic phase, and at the end of the postanhepatic phase. After completing the course, the trainees filled in a questionnaire to evaluate its usefulness. Analysis of variance was applied to score changes in anesthetic quality criteria. RESULTS: After implantation, changes in metabolic (acidosis) and cardiac (hypotension and bradycardia) status were the most critical abnormalities the trainees faced. Their skill in coping with hemodynamic and metabolic changes improved significantly (P<.05). All participants expressed a preference for receiving training in a porcine model before providing anesthesia in this surgical setting. CONCLUSIONS: Under this training model, the anesthesiologists understood and were able to manage the hemodynamic and physiologic changes that develop during a liver transplant procedure. We believe that training using a porcine model allows an anesthesiologist to acquire experience and skill in this setting.

Human tuberculosis due to Mycobacterium bovis and M. caprae in Spain, 2004-2007.

OBJECTIVE: To identify the characteristics associated with human tuberculosis (TB) caused by Mycobacterium bovis and M. caprae in Spain. DESIGN: Retrospective study covering all M. bovis and M. caprae isolates identified at the National Mycobacterial Reference Laboratory (NRL) from 2004 to 2007. We studied the microbiological and epidemiological characteristics of patients and performed a genetic analysis of isolates. RESULTS: The study covered 110 isolates (89 M. bovis and 21 M. caprae) that accounted for respectively 1.9% and 0.3% of the M. tuberculosis complex isolates available at the NRL. Data on risk of exposure to M. bovis or to M. caprae were available in 82 (74%) of the 110 cases, with 60 (73%) registering a probable or possible risk of exposure and 22 (27%) registering no risk. Probable exposure mainly included crop and livestock farmers, and possible exposure included patients born in countries with a high prevalence of bovine TB. Spoligotyping of strains yielded 36 different patterns, with SB0121, SB0134 and SB0157 being predominant. CONCLUSIONS: In Spain, cases of human TB due to M. bovis and M. caprae represent a small proportion of all TB cases, and for a high percentage of cases this is linked to occupational exposure and coming from countries endemic for bovine TB.

Population-based contact investigation of a cluster of tuberculosis cases in a small village.

A cluster of five cases of tuberculosis (TB) in persons aged 19-23 years who were not close contacts was detected in a small village in Spain in 2006. All culture isolates had the same chromosomal-DNA restriction pattern. Contact investigations of family members, friends, workmates and schoolmates were complemented with tuberculin screening offered to the resident population born between 1976 and 1995. Expanded contact tracing detected two new cases of TB, 27 tuberculin conversions and an excess of latent tuberculosis infections (LTI) in persons born between 1978 and 1990. The contacts of two cases had a significantly elevated prevalence of LTI. Two secondary cases of TB, 33.3% of those diagnosed with LTI and 47.8% of the converters were unaware of any contact with the TB cases, but had frequented some of the same bars. This study suggests that a considerable percentage of the episodes of TB transmission in young people may escape detection in conventional contact studies.

Effects of premedication with tiletamine/zolazepam/medetomidine during general anesthesia using sevoflurane/fentanyl in swine undergoing pancreas transplantation.

OBJECTIVE: To assess cardiac and hemodynamic responses and body temperature during long-term general anesthesia using sevoflurane/fentanyl after premedication with a tiletamine/zolazepam/medetomidine combination in swine undergoing experimental pancreas transplantation. MATERIALS AND METHODS: Twelve Landrace female pigs of means weight 46.4 +/- 5.1 kg were premedicated by intramuscular administration of tiletamine/zolazepam (3.5 mg/kg), medetomidine (0.03 mg/kg), and atropine (0.02 mg/kg), before anesthesia with 0.75 minimum alveolar concentration sevoflurane and continuous intravenous fentanyl infusion (5.7 +/- 0.7 microg/kg/h). Assessment of heart rate, arterial blood pressure, and temperature in pigs undergoing allogenic pancreas transplant surgery were registered at the start of anesthesia (T0), as well as at 60 (T60), 120 (T120), and 180 (T180) minutes after T0, and finally at the end of anesthesia (T anesthesia end), when we switched off the sevoflurane vaporizer. Analysis of variance was used to determine differences between times with P < .05 considered significant. Results are given as mean values +/- standard deviations. RESULTS: Arterial blood pressure significantly decreased from T120 to the end of anesthesia, while a significantly decreased heart rate was only evident at T60. Body temperature decreased significantly from T60 to the end of anesthesia. These decreases, however, lacked clinical relevance; all parameters were within normal range. No major anesthetic complications were observed in this study. CONCLUSIONS: The administration of a tiletamine/zolazepam/medetomidine combination as premedication in swine subjected to pancreas transplantation allowed for a safe reduction of sevoflurane/fentanyl requirements during long-term general anesthesia. Despite arterial blood pressure and body temperature evidencing a decrease during anesthetic maintenance, all parameters remained within normal range values.

Short- and long-term modulation of the lutein epoxide and violaxanthin cycles in two species of the Lauraceae: sweet bay laurel (Laurus nobilis L.) and avocado (Persea americana Mill.).

Short- and long-term responses of the violaxanthin (V) and lutein epoxide (Lx) cycles were studied in two species of Lauraceae: sweet bay laurel (Laurus nobilis L.) and avocado (Persea americana L.). The Lx content exceeded the V content in shade leaves of both species. Both Lx and V were de-epoxidised on illumination, but only V was fully restored by epoxidation in low light. Violaxanthin was preferentially de-epoxidised in low light in L. nobilis. This suggests that Lx accumulates with leaf ageing, partly because its conversion to lutein is limited in shade. After exposure to strong light, shade leaves of avocado readjusted the total pools of alpha- and beta-xanthophyll cycles by de novo synthesis of antheraxanthin, zeaxanthin and lutein. This occurred in parallel with a sustained depression of F(v)/F(m). In Persea indica, a closely related but low Lx species, F(v)/F(m) recovered faster after a similar light treatment, suggesting the involvement of the Lx cycle in sustained energy dissipation. Furthermore, the seasonal correlation between non-reversible Lx and V photoconversions and pre-dawn F(v)/F(m) in sun leaves of sweet bay supported the conclusion that the Lx cycle is involved in a slowly reversible downregulation of photosynthesis analogous to the V cycle.

Comparison of GenoType MTBC with RFLP-PCR and multiplex PCR to identify Mycobacterium tuberculosis complex species.

The aims of the work presented here were to evaluate a commercial system based on DNA hybridization technology on nitrocellulose strips (GenoType MTBC; Hain Diagnostika, Nehren, Germany) for identifying Mycobacterium tuberculosis complex isolates to the species level and to compare the results with those obtained using the RFLP-PCR and multiplex PCR molecular techniques, biochemical tests and susceptibility testing. The commercial system correctly identified 102 of 103 (99.03%) strains studied, indicating it is capable of discriminating among the tuberculosis complex species.

Relationship of bispectral index values, haemodynamic changes and recovery times during sevoflurane or propofol anaesthesia in rabbits.

The aim of this study was to determine and compare the degree of hypnosis achieved during propofol or sevoflurane anaesthesia in rabbits using bispectral index (BIS), and to evaluate its usefulness as a predictor of both haemodynamic changes during anaesthesia and recovery times. Twenty adult male New Zealand White rabbits, average weight 4.4 +/- 0.4 kg, were used for this study. Animals were randomly allocated to one of two groups with 10 rabbits/group. An electroencephalographic recording was obtained from each conscious rabbit prior to drug administration. All animals received buprenorphine as a preanaesthetic medication (0.05 mg/kg, intravenous [i.v.]). Anaesthesia was induced with propofol (8 mg/kg, i.v.) in all animals; 10 rabbits were maintained with sevoflurane via inhalation (1 minimum alveolar concentration--end-tidal sevoflurane concentration of 3.7%--at a fresh gas flow rate of 3 L/min; group I), and 10 were maintained with i.v. propofol (0.6 mg/kg/min; group II). The rabbits were orotracheally intubated and spontaneous ventilation was maintained throughout the study (100% oxygen). After abdominal surgery through a ventral midline laparotomy, rabbits were allowed to recover from anaesthesia. Cardiovascular variables and BIS values were recorded at intervals throughout the procedure, as was the duration of recovery from anaesthesia. In both groups, mean BIS values were significantly decreased immediately after induction, compared with baseline values obtained during consciousness. Anaesthetic depth (evaluated by clinical observation) was similar in both groups; however, group II rabbits had significantly higher (P<0.001) BIS values from 30 s before incision until anaesthesia was discontinued. There was no significant difference in BIS recorded 1 and 5 min after incision as compared with values obtained 30 s before incision in either group. During sevoflurane or propofol administration, correlations were found between BIS values and mean arterial blood pressure (MABP), and between BIS values and heart rate (HR). Mean BIS values at discontinuation of administration of the anaesthetic agent were greater in group II (69.1 +/- 6.0) than in group I (49.3 +/- 2.2). However, recovery from anaesthesia was significantly longer in group II (38.4 +/- 7.2 min) than in group I (11.5 +/- 2.5 min). In conclusion, BIS can be used to differentiate between conscious and unconscious states during anaesthesia in rabbits. BIS values derived from an electroencephalogram at the end of anaesthesia were not useful for predicting the speed of anaesthetic recovery in sevoflurane or propofol-anaesthetized rabbits undergoing abdominal surgery. Despite the correlation found between BIS and haemodynamic parameters, its usefulness as a predictor of clinically important changes in arterial blood pressure and HR in anaesthetized rabbits was limited.

Systematic molecular characterization of multidrug-resistant Mycobacterium tuberculosis complex isolates from Spain.

We used spoligotyping and restriction fragment length polymorphism (RFLP) of the IS6110-insertion sequence to study the molecular epidemiology of multidrug-resistant (MDR) tuberculosis in Spain. We analyzed 180 Mycobacterium tuberculosis complex isolates collected between January 1998 and December 2000. Consecutive isolates from the same patients (n = 23) always had identical genotypes, meaning that no cases of reinfection occurred. A total of 105 isolates (58.3%) had unique RFLP patterns, whereas 75 isolates (41.7%) were in 20 different RFLP clusters. Characterization of the katG and rpoB genes showed that 14 strains included in the RFLP clusters did not actually cluster. Only 33.8% of the strains isolated were suggestive of MDR transmission, a frequency lower than that for susceptible strains in Spain (46.6%). We found that the Beijing/W genotype, which is prevalent worldwide, was significantly associated with immigrants. The 22 isolates in the largest cluster corresponded to the Mycobacterium bovis strain responsible for two nosocomial MDR outbreaks in Spain.

Gas exchange characteristics of a Canarian laurel forest tree species (Laurus azorica) in relation to environmental conditions and leaf canopy position.

Diurnal courses of gas exchange were measured over a 1-year period in fully expanded current-year leaves in the upper (sun-exposed, 18 m above ground) and the lower (shaded, 12 m above ground) canopy of Laurus azorica (Seub.) Franco, a major canopy species of the Canarian laurel forest in Tenerife, Canary Islands, Spain. Laurus azorica exhibited high leaf plasticity in gas exchange characteristics, with a maximum carbon assimilation rate (Amax) of shade leaves about 50% that of sun leaves. This difference reflects the high leaf area index (LAI) of the stand and the correspondingly sharp light attenuation with increasing canopy depth. In sun leaves, Amax peaked at about 11 micromol m-2 s-1 and maximum transpiration (E) was about 8 mmol m-2 s-1, which corresponded with a maximum stomatal conductance (gs) of about 650 mmol m-2 s-1. Mean maximum instantaneous water-use efficiency (WUE) was 1.5 mmol mol-1 and the mean maximum A/gs was 20-35 micromol mol-1. Mean minimum internal CO2 concentration (Ci) was 225 micromol mol-1. Although high air vapor pressure deficit (VPD) caused a small decrease in gs, it remained high enough to maintain relatively high A and E. These gas exchange characteristics indicate a non-conservative use of water, which is appropriate for a species subject to droughts that are mild or of short duration. In this respect, Laurus azorica differs from its congener, L. nobilis L., of the Mediterranean region and other shrubs growing in Mediterranean-type climates in California and Chile that have to withstand more severe or more prolonged droughts.

[Cognitive disorders in patients with Huntington's disease]. / Trastornos cogitivos en pacientes con enfermedad de Huntington.

INTRODUCTION: Huntington s disease has been clearly recognized since 1872. It is characterized by the appearance of a motor disorder (chorea) accompanied by selective cognitive deterioration which is not interfered with by aging. DEVELOPMENT: Since the genetic defect causing it has been identified (expansion of CAG triplets on the IT 15 gene of chromosome 4) it has been possible to study families from the preclinical stage (asymptomatic persons who carried the mutation) to the stage of full development of the clinical syndrome. The behaviour disorders most often seen in these patients are depression, mania, schizophrenia, paranoia, anxiety, obsessive and obsessive compulsive disorders although other disorders may also occur. Different clinical forms of motor disorders and dementia have been reported in relation to the age of onset of the symptoms. The commonest cognitive symptoms are defects of attention, memory, planning, sequencing and visuo spatial deficits, as occurs in subcortical dementia. Our objective is to present the different clinical forms of the disorder according to the age of presentation, implication of the symptoms, severity of the genetic defect (number of CAG triplets) and to describe the study made of asymptomatic carriers so as to be able to detect incipient cognitive deterioration in these persons.

[Dementia in progressive supranuclear paralysis patients]. / Demencia en pacientes con parálisis supranuclear progresiva.

INTRODUCTION: Progressive supranuclear paralysis is difficult to detect in its initial stages. Its symptoms are not specific and often the patients are mistaken as Parkinson s disease patients, or even Alzheimer s ones. DEVELOPMENT: Initial features in progressive supranuclear paralysis are typically a gait disorder with frequent falls, behavioral disorder and often dysarthria. The gaze disorder, showing voluntary conjugate gase paralysis is characteristic, but it can appear late in the course of disease. Other motor signs are axial rigidity, bradykinesia, stiffness, and rarely chorea, ataxia, muscle weakness or myoclonus. Pseudobulbar paralysis is the more remarkable clinical finding. These motor symptoms are accompanied by cognitive disturbances, the typical ones of subcortical dementia, with mind slowness, apathy, depression, and, more often that in other primary dementias, psychotic features and relatively early behavioral disorders. A useful feature to distinguish the mental changes of progressive supranuclear paralysis with other primary subcortical dementias is a more remarkable impairment in visuospatial function, because of the need of a good gaze function to accomplish it. Progressive supranuclear paralysis patients work better in verbal tests that in visuospatial test. We try to describe clinical data and evolutive profile of this entity, whose cognitive disturbances as described by Albert in 1974 strongly stabilized the concept of subcortical dementia.

[Amusias]. / Las amusias.

INTRODUCTION: We review the definition of the amusias and the cultural components involved in musical experience. We review the characteristics of musical language, perception and performance of it together with reading and writing it. DEVELOPMENT: We analyze the above data and significant clinical cases. We discuss whether in evaluation of the amusias it may be relevant to have had been taught music, since in this condition the functional specialization of the cerebral cortex has different topography of the lesions in persons who have or have not had musical education. CONCLUSIONS: We consider that in persons who have studied musical language, amusia should be evaluated as a second language, and its pathology as aphasia for musical language. In persons without musical education the dysperceptive amusias are a purely agnostic phenomenon with neuropsyschological characteristics which are different to those seen in persons who have had an education in music.

rpoB mutations as an epidemiologic marker in rifampin-resistant Mycobacterium tuberculosis.

SETTING: Cases of rifampin-resistant Mycobacterium tuberculosis from the prison population in Madrid and from the general population in Spain. OBJECTIVE: To identify the rpoB mutations associated with resistance to rifampin and to investigate rpoB genotyping as an epidemiological marker in rifampin-resistant M. tuberculosis. DESIGN: Twenty-nine rifampin-resistant clinical isolates of M. tuberculosis, 15 obtained from the prison population in Madrid and 14 from the general population in Spain, were characterized by sequence analysis of the 81-bp core region of the rpoB gene and IS6110 DNA fingerprinting. RESULTS: All the isolates had mutations in rpoB, with those in codon 531 accounting for 41% of the total. Twenty-three (79%) isolates were highly resistant to rifampin (minimum inhibitory concentration > or = 64 mg/L). Nineteen different IS6110 fingerprints were observed: one was shared by seven isolates, one by three, two by two, and 15 were unique. Two IS6110 clusters could be divided into subclusters on the basis of rpoB analysis. Epidemiologic links were identified among patients whose isolates had identical IS6110 patterns and rpoB genotypes, but not between those with identical IS6110 patterns and different rpoB genotypes. CONCLUSION: Characterization of rpoB mutations can provide information about susceptibility to rifampin and be a useful epidemiological tool for discrimination of rifampin-resistant strains of M. tuberculosis with identical IS6110 fingerprints.