[Analysis of the failures of a cemented constrained liner model in patients with a high dislocation risk]

OBJECTIVE

To evaluate the short-term results of an ultra high molecular weight polyethylene retentive cup in patients at high risk of dislocation, either primary or revision surgery.

MATERIAL AND METHOD

Retrospective review of 38 cases in order to determine the rate of survival and failure analysis of a constrained cemented cup, with a mean follow-up of 27 months. We studied demographic data, complications, especially re-dislocations of the prosthesis and, also the likely causes of system failure analyzed.

RESULTS

In 21.05% (8 cases) were primary surgery and 78.95% were revision surgery (30 cases). The overall survival rate by Kaplan-Meier method was 70.7 months. During follow-up 3 patients died due to causes unrelated to surgery and 2 infections occurred. 12 hips had at least two previous surgeries done. It wasn't any case of aseptic loosening. Four patients presented dislocation, all with a 22 mm head (P=.008). Our statistical analysis didn't found relationship between the abduction cup angle and implant failure (P=.22).

CONCLUSIONS

The ultra high molecular weight polyethylene retentive cup evaluated in this series has provided satisfactory short-term results in hip arthroplasty patients at high risk of dislocation.

[Asterixis in focal brain lesions]

Asterixis is a motor control disorder characterized by the presence of abnormal movements of the lower limbs in the vertical plane during posture maintenance. Asterixis is usually bilateral and associated with toxic-metabolic metabolic encephalopathies. Unilateral asterixis is less frequent and it normally indicates focal brain damage. We report the cases of four patients (two males/two females), aged 57 to 83 years, suffering from uni or bilateral asterixis associated with focal brain damage. All patients underwent CT brain scan and a neurophysiological study (parietal EMG and/or PES). In addition, any toxic-metabolic cause that could be produced by this clinical phenomenon was ruled out with the appropriate testing. Unilateral asterixis is a clinical symptom that may indicate the presence of focal brain damage. Often, it is ignored or overlooked during routine neurological examinations. On the other hand, the presence of a bilateral asterixis is not always indicative of a toxic-metabolic encephalopathy.Rarely, such as in one of the cases herein presented, bilateral asterixis can also appear associated with structural brain lesions. Although asterixis diagnosis is fundamentally clinical, the neurophysiological study contributes to verify the diagnosis.

Antibodies to human recombinant tissue transglutaminase may detect coeliac disease patients undiagnosed by endomysial antibodies

BACKGROUND

The screening and diagnosis of coeliac disease have been simplified by the advent of new serological tools.

AIM

To assess the clinical utility of a newly developed kit for antibodies to human recombinant tissue transglutaminase (hu-anti-tTG) in a large population of patients undergoing intestinal biopsy for suspected intestinal disorders.

METHODS

We evaluated 426 serum samples from consecutive adult patients (250 from untreated coeliac disease patients and 176 from individuals in whom a diagnosis of coeliac disease had been excluded), obtained at the time of intestinal biopsy. Samples were tested for immunoglobulin A (IgA) hu-anti-tTG by enzyme-linked immunoabsorbent assay, IgA endomysial antibodies (EmA) by indirect immunofluorescence and IgA and IgG antigliadin antibodies by enzyme-linked immunoabsorbent assay. A sub-group of samples was also assessed for a guinea-pig-based anti-tissue transglutaminase.

RESULTS

According to the cut-off for hu-anti-tTG, the sensitivity, specificity and positive and negative predictive values were 91%, 96%, 97% and 87%, respectively. Simultaneous determination of EmA showed values of 86%, 100%, 100% and 83% for the same parameters. Although 19 coeliac disease patients (7.6%) were negative for EmA and hu-anti-tTG, both tests rendered superior statistical values to antigliadin antibody tests. At diagnosis, IgA deficiency was detected in 11 patients, but both assays were able to detect samples with mild to moderate deficiency. The comparison of hu-anti-tTG with EmA showed excellent concordance between the tests (kappa statistic, 0.85). Discordance was observed in 20 samples from coeliac disease patients (8%) and in nine samples from controls (5%). Fifteen samples had an EmA-negative but hu-anti-tTG-positive serology, and five showed the converse pattern. Comparison of human recombinant and guinea-pig tests showed concordant results in 96% of cases.

CONCLUSIONS

The quantitative determination of hu-anti-tTG type IgA using a commercial enzyme-linked immunoabsorbent assay kit was highly sensitive and specific for the detection of coeliac disease. Our results in a large population of patients with a clinical condition suggestive of the disorder demonstrated that the test can be used to detect a substantial number of patients otherwise unrecognized by IgA EmA.

Is it necessary to screen for celiac disease in postmenopausal osteoporotic women?

Decreased bone mass is a frequent finding in celiac patients, and subclinical celiac disease (CD) appears to be unusually overrepresented among patients with idiopathic osteoporosis. Since silent CD may be more common than previously believed, it has been suggested that all osteoporotic patients should be checked for occult CD. The aim of this study was to explore the prevalence of CD in a well-defined population of postmenopausal osteoporotic women. We evaluated 127 consecutive postmenopausal patients (mean age: 68 years; range: 50-82 years) with verified osteoporosis. The observed prevalence of CD in this group was compared to that observed in a group of 747 women recruited for a population-based study. The screening algorithm used to diagnose CD was based on a 3-level screening using type IgA and IgG antigliadin antibodies (AGA) in all the patients (1st level) followed by antiendomysial antibodies (EmA) and total IgA (2nd level) of samples testing positive, and intestinal biopsy of positive cases (3rd level). At the end of the serological screening, only 1 of 127 osteoporotic women was eligible for jejunal biopsy showing a characteristic celiac flat mucosa (prevalence 7.9 x 1,000; 95% CI 0.2-43.1). In addition, CD was diagnosed in 6 of 747 women of the population-based study (prevalence: 8.0 x 1,000; 95% CI 3.3-18.3). There was no significant difference between the two groups. Therefore, our study showed that the prevalence of CD in postmenopausal osteoporotic women was lower than that reported in previous studies and similar to that of the general population. In conclusion, although the relatively small size of the group tested does not allow us to be conclusive, the results suggest that a case finding policy in postmenopausal osteoporosis would have a high cost/benefit ratio except for patients not responding to conventional therapies, or presenting borderline laboratory results.

[Frequency of retinal changes in myopia in a black population]

PURPOSE

Retinal detachment is the main complication of peripheral retinal lesions in myopia but seems rare in black people. We analysed peripheral retinal changes in myopia in a black population.

MATERIAL AND METHODS

This study was conducted by a single ophthalmologist. The tests included a refraction, a retinal biomicroscopy (with a Volk lens and a 3-mirror Goldmann lens) and an indirect ophthalmoscopy. The results were compared by a chi square test.

RESULTS

50 people (100 eyes) were available for examination. The mean age was 28.21 years, the two extremes being at 11 and 54 years, with 68% females and 32% males. In 50 eyes the spheric equivalent was between -1 and -5.75 diopters (group I). In 50 eyes the spheric equivalent was greater than or equal to -6 diopters (group II). Snow was found in 16% of cases in group I and 34% of cases in group II (p = 0.0366). Tears were found in 2% of cases in group I and 12% of cases in group II (p = 0.116). Lattice degeneration was found only in group II.

CONCLUSION

Retinal tear frequency was similar to the results of other authors. Comparative studies are necessary to evaluate the risk of retinal detachment in black populations.

Prevalence of celiac disease in Argentina: screening of an adult population in the La Plata area

OBJECTIVES

Up to now, the epidemiological characteristic of celiac disease among adults in South America remains unknown. The present prospective screening was designed to determine the prevalence of celiac disease in adults from the general population in an urban area of Argentina.

METHODS

Between January. 1998, and May, 2000, all couples attending a centralized laboratory for an obligatory prenuptial examination in the La Plata area were offered participation in a screening program for celiac disease. The study included 2000 subjects (996 women; median age 29 yr, range 16-79 yr). All individuals completed a clinical questionnaire at the time that serum samples were obtained. A three-step screening protocol was used, as follows: 1) all samples were tested for antigliadin antibodies (AGAs) (type IgA and IgG); 2) samples that were IgA AGA positive were tested for antiendomysial antibody (EmA type IgA); samples that were positive for AGA-G but negative for IgA AGAs were tested for total IgA serum levels and EmA type IgG; and 3) subjects who were EmA-positive were referred for intestinal biopsy.

RESULTS

At the end of the screening we detected 10 subjects who were EmA-A positive and two others who were IgA-deficient (both were EmA-G positive). Up to now, 11 of the 12 subjects (including nine EmA-positive and two IgA-deficient subjects) had endoscopic intestinal biopsies showing the characteristic celiac histology. The remaining EmA-positive individual was considered to be affected by celiac disease. The overall prevalence assessed was 1:167 (6.0 x 1000 subjects; 95% CI = 3.1-10.5). Eight of the 12 (67%) subjects were female (1:124; 8.0 x 1000; 95% CI = 3.5-15.8) and four (33%) were male (1:251; 4.0 x 1000; 95% Cl = 1.1-10.2). Although eight new patients were considered to be asymptomatic, three presented with a subclinical course and one was classically symptomatic. Only one patient had been previously diagnosed with celiac disease.

CONCLUSIONS

Our screening protocol showed a very high prevalence of celiac disease for an urban area of Argentina that is ethnically similar to 90% of the general population of the country. The prevalence among women was double that for men, and the heterogeneous clinical picture of new patients showed predominance of asymptomatic cases.

Superior efficacy of olanzapine over haloperidol: analysis of patients with schizophrenia from a multicenter international trial

BACKGROUND

Previously, a double-blind, 6-week, parallel-group trial compared the therapeutic profiles of olanzapine (5-20 mg/day; N = 1,336) and haloperidol (5-20 mg/day; N = 660) in 1996 patients with DSM-III-R schizophrenia (83.1%) or schizophreniform (1.9%) or schizoaffective disorders (15.0%) and showed olanzapine to have a superior, broader spectrum of efficacy as well as a more favorable adverse event profile. The present post hoc analysis examined the efficacy of olanzapine compared with haloperidol in the schizophrenic cohort of that study and in subgroups of schizophrenic patients defined by baseline symptom profile and course of illness.

METHOD

A total of 1,658 patients were included. Patients were included in analyses of change if they had both a baseline and at least 1 postbaseline measurement (N = 1,622; 1,096 olanzapine-treated patients, 526 haloperidol-treated patients). An analysis of variance was used to compare treatment effects on efficacy measurements including the Brief Psychiatric Rating Scale (BPRS; scored 0-6) and the Positive and Negative Syndrome Scale (total, positive subscale, and negative subscale scores).

RESULTS

Olanzapine-treated patients exhibited statistically significantly greater improvements from baseline (last observation carried forward) on all efficacy measurements. Olanzapine-treated patients with predominantly positive, predominantly negative, or mixed symptoms had statistically significantly greater improvements in BPRS total scores compared with similar haloperidol-treated patients. Patients with primarily chronic negative symptoms and patients with chronic or subchronic courses of illness had statistically significantly greater mean improvements from baseline on the BPRS total with olanzapine compared with haloperidol. Furthermore, within the olanzapine treatment group, patients with a subchronic course of illness had greater mean improvements than patients with a chronic course of illness.

CONCLUSION

Olanzapine was more effective than haloperidol in treating a varied spectrum of patients with schizophrenia, including patients with positive, negative, or mixed symptom profiles and either a chronic or subchronic course of illness.

Tissue transglutaminase antibodies in celiac disease: assessment of a commercial kit

OBJECTIVE

Tissue transglutaminase was identified as the autoantigen eliciting endomysial antibody. A homemade enzyme-linked immunosorbent assay (ELISA)-based test was recently developed to determine quantitative titers of IgA antitissue transglutaminase antibody. Our objective in this study was to assess the suitability of a newly developed commercial kit for quantitative determination of antibody in patients with untreated celiac disease.

MATERIALS

We tested serum samples from 79 untreated celiac patients, 42 healthy blood donors, and 18 patients with nonceliac intestinal disorders evaluated in two different centers. Samples were tested for antitissue transglutaminase, and antiendomysial and antigliadin antibodies in the center where diagnosis was performed. To assess interlaboratory variability of methods, 24 samples randomly selected were blindly tested in both centers. Antitissue transglutaminase antibodies were determined using a commercial kit (INOVA Diagnostics, Inc., San Diego, CA).

RESULTS

Untreated celiac patients had significantly higher titers of antitissue transglutaminase than healthy and disease controls (p < 0.00001). According to the cut-off provided by the manufacturers (20 AU/mL), overall sensitivity was 92% (85% for one center and 100% for the other) and specificity was 98% (100% and 95%, respectively). Antiendomysial antibody was 86% sensitive and 100% specific. Discordance between antitissue transglutaminase and antiendomysial antibodies was detected in 13% of patients. Although two antitissue transglutaminase-negative cases had a positive antiendomysial antibody, the inverse situation was found in eight cases. A blind determination of antitissue transglutaminase on the same samples evidenced a good agreement (kappa statistic: 0.66) between both centers when assessment was qualitative (based on the decision of positive or negative). Although correlation of titers for both determinations was highly significant (r: 0.902, p < 0.00001), a very wide interlaboratory variability (median: 50%) was detected when absolute values were considered.

CONCLUSIONS

The quantitative determination of antitissue transglutaminase using a commercial kit was highly sensitive and specific for detection of celiac disease. We observed an incomplete overlapping with antiendomysial antibody. The very high variability of values between laboratories still remains to be solved so as to propose the commercial ELISA assay for the screening of celiac disease.

Imitative learning of artificial fruit processing in children (Homo sapiens) and chimpanzees (Pan troglodytes)

Observational learning in chimpanzees and young children was investigated using an artificial fruit designed as an analog of natural foraging problems faced by primates. Each of 3 principal components could be removed in 2 alternative ways, demonstration of only one of which was watched by each subject. This permitted subsequent imitation by subjects to be distinguished from stimulus enhancement. Children aged 2-4 years evidenced imitation for 2 components, but also achieved demonstrated outcomes through their own techniques. Chimpanzees relied even more on their own techniques, but they did imitate elements of 1 component of the task. To our knowledge, this is the first experimental evidence of chimpanzee imitation in a functional task designed to simulate foraging behavior hypothesized to be transmitted culturally in the wild.

What's inside someone's head? Conceiving of the mind as a camera helps children with autism acquire an alternative to a theory of mind

A group of children with autism were taught a specific strategy to help them solve a series of theory of mind problems. We focused our teaching on the false-belief task and taught them the analogy that people have photos in their heads. This strategy draws on a domain of intact cognition in autism (understanding photographic representations) to bypass a cognitive impairment in a certain domain (understanding mental state representations). All the children were able to understand photographic misrepresentation during teaching and, following specific teaching, they could use the strategy of visualising photos in characters' heads to predict the character's behaviour. In contrast, none of the children could use the photo strategy to predict a character's mental states. The educational and theoretical implications of this study are discussed.

Cytological, immunocytochemical and ultrastructural study of the adenohypophyseal pars distalis of the kid (Capra hircus): the TSH cell

The structure and ultrastructure of the adenohypophyseal pars distalis in kids of the Murciano-granadiana breed (18 males and 12 females), aged 2-3 months and with an average carcass weight of 8 kg has been studied. Techniques of staining (Tetrachrome Herlant's, and Cleveland-Wolfe) and histochemistry (PAS, PAS-OG and BA-PAS-OG) contrasted with immunolabelling (PAP) have been used. In addition an ultrastructural study has been made and nucleus and cytoplasm, secretory granules, mitochondria and lysosomes have been measured with a semiautomatic image analyzer (IBAS-1). TSH cells are found in sagittal section in the anterior area and in an antero-caudodorsal band, and transversally in the ventral and medial region; they are 6% and their average size is 14.15 microns. Ultrastructurally they are a single cellular type with spherical granules whose size is 195 nm in males and 149 in females; these granules are characterized by a clear halo and a variable electronic density. The rough endoplasmic reticulum is found as slightly enlarged vesicles with a homogeneous and moderately electro-dense content or in concentric stratifications.

Injection of collagenase in the treatment of herniated lumbar disk. Initial clinical report

Twenty-nine patients with persistent, low back and sciatic pain received intradiscal collagenase at a single abnormal disk space after two months of conservative therapy and two weeks of additional bed rest. Complete pain relief was achieved in six patients (21%), notable relief in 12 (42%), moderate in six (21%), and slight in one. Four patients (14%) who obtained no improvement by enzyme injection recovered after extruded disk fragments were removed from the spinal canal during a later operation. Pain relief after collagenase injection took place gradually over a two- to three-week period and was associated with some early backache. Improvement then continued at a slower rate for two to three months. There were no adverse effects of enzyme therapy. Injected disk spaces usually showed radiological narrowing.