Evaluation of the immunochromatographic CORIS Giardia-Strip test for rapid diagnosis of Giardia lamblia.

The aim of this study was to evaluate the performance of the CORIS Giardia-Strip test (CORIS Bioconcept, Gembloux, Belgium) as a rapid initial method for the routine diagnosis of giardiasis. Compared to a commercial ELISA-coproantigen test (ProSpect Giardia-ELISA-microplate assay; Remel, Lenexa, KS, USA), the commercial strip test had a sensitivity of 58%, a specificity of 99%, a positive predictive value of 93% and a negative predictive value of 93% (n=158). These results are comparable to those obtained using microscopy of direct wet-mounted stool. Since the CORIS Giardia-Strip test is simpler to perform, it can replace direct wet-mounted stool microscopy for the rapid diagnosis of giardiasis; however, its sensitivity is inferior to that of other immunochromatographic antigen detection tests and fresh stool samples are required for its use. Nevertheless, the results suggest that a positive CORIS Giardia-Strip test outcome does not need confirmation, while samples with negative results should be re-examined using another, more sensitive, test.

The seroprevalence of cystic hydatidosis in Oman.

The presence of antibodies against Echinococcus granulosus in sera from 306 humans and 390 camels in Oman was investigated by indirect haemagglutination assays. Only one of the human and five of the camel sera gave positive reactions. The reactivities of the human sera were confirmed by ELISA. These results, together with isolated reports of hydatid cysts, indicate that E. granulosus is endemic in Oman, although with a low prevalence.

Circumscribed intestinal protein loss with deficiency in CD4+ lymphocytes after the Fontan procedure.

UNLABELLED: Protein-losing enteropathy is an important complication after right heart bypass operations (Fontan procedure). Laboratory examinations usually reveal hypoalbuminaemia, hypoproteinaemia, elevated alpha(1)-antitrypsin clearance, and lymphocytopenia. A case of protein-losing enteropathy after Fontan procedure is reported with a circumscribed protein loss in the region of the terminal ileum despite good haemodynamics. The patient developed only mild hypoalbuminaemia and no diarrhoea but severe cellular and humoral immune abnormalities, namely a markedly decreased proportion of CD4+ lymphocytes but normal proportion of CD8+ lymphocytes (CD4+ 14%, CD8+ 23%) and decreased serum levels of immunoglobulin G. Intestinal biopsies revealed normal mucosa. This report is unique as it is the first to describe a ratio of CD4+ to CD8+ lymphocytes <1 due to an almost selective loss of CD4+ lymphocytes and a circumscribed intestinal protein loss in a patient who developed protein-losing enteropathy after Fontan operation. CONCLUSION: There is a severe decrease of CD4+ lymphocytes of unknown origin in a patient with circumscribed intestinal protein loss after Fontan operation. Passive leakage of lymph fluid due to abnormal systemic venous pressure is not a sufficient explanation of the almost selective loss of CD4+ lymphocytes. Primary or secondary activation of the immune system may influence structural integrity and permeability of the intestinal wall and may play a triggering role in protein-losing enteropathy after the Fontan procedure.

Cardiac sympathetic denervation in early stages of amyotrophic lateral sclerosis demonstrated by 123I-MIBG-SPECT.

Involvement of the autonomic cardiac nervous system in early stages of amyotrophic lateral sclerosis (ALS) was evaluated in 40 patients. I-123-metaiodobenzylguanidine-single photon emission computed tomography (MIBG-SPECT) and heart rate variability (HRV) yielded information about sympathetic and parasympathetic innervation of the heart. MIBG-SPECT is a sensitive diagnostic method for demonstration of early cardiac sympathetic denervation. Both sympathetic and parasympathetic dysfunction was observed in 16 (40%) out of 40 patients. Mean cardiac MIBG uptake as demonstrated by the heart/mediastinum ratio was significantly reduced in all ALS patients in comparison with controls (P<0.01). The global MIBG-SPECT score was clearly abnormal in 29% and slightly abnormal in 22% of patients. HRV was diminished in 6 of 38 patients, 4 of whom having an abnormal MIBG-SPECT score as well. The presented results indicate that ALS patients with mild to moderate impairment may have evidence of postganglionic sympathetic adrenergic cardiac or cardiovagal denervation. To our knowledge, this is the first study indicating possible postganglionic sympathetic denervation in ALS. The original concept of ALS as an isolated degeneration of motor neurons seems to extend to a more widespread understanding of the disease which possibly represents different entities.

[Ictal syncopes. Cardiac sympathetic innervation disorder as the etiology?]. / Iktuale Synkopen. Kardiale sympathische Innervationsstörung als Ursache?

We report 3 cases of an ictal sinus arrest. All patients suffered from temporal lobe epilepsy (TLE). Seizures were monitored with simultaneous video-eeg during preoperative epilepsy diagnosis. One patient with cortical dysplasia, who frequently suffered from long lasting syncopes, had a nearly completely missing cardiac sympathetic innervation in MIBG-SPECT (=Meta-Iodide-Benzyle-Guanidine-single-photon-emission tomography). Cardiac investigation including long-term ECG and echocardiography had shown normal findings. After epilepsy surgery the syncopal events in all patients disappeared. A dominant parasympathetic ictal stimulus following excitation of the reticular formation might cause the ictal bradycardia and sinus arrest. A missing sympathetic innervation, possibly occurring as fehlbildung together with cortical dysplasia, which makes autoregulation impossible, might then be the explanation for sudden cardiac ictal death.

Positive I-123-MIBG-scintigraphy in osteosarcoma.

I-123-MIBG scintigraphy has become a standard imaging technique in the detection of neuroendocrine or neurocrest derived tumors, especially neuroblastoma and pheochromocytoma. We report on a positive I-123-MIBG uptake in a pediatric osteosarcoma patient and demonstrate, that unusual results still occur with this established imaging method.

[Changes in regional CNS perfusion in obstructive sleep apnea syndrome: initial SPECT studies with injected nocturnal 99mTc-HMPAO]. / Veränderungen der regionalen ZNS-Perfusion beim obstruktiven Schlafapnoe-Syndrom: Erste SPECT-Untersuchungen mit nächtlich injiziertem 99mTc-HMPAO.

Some of the clinical features of obstructive sleep apnoea syndrome (OSA) are suggestive of impaired cerebral blood flow. Cerebral blood flow alterations might, for example, be responsible for headaches, which are frequent complaints in patients with OSA. Even the high frequency of ischaemic cerebral complications in patients with OSA might be caused in part by sleep apnoea-associated impairment of cerebral perfusion. Previous studies have demonstrated reduced total cerebral blood flow in patients with OSA, but regional changes of cerebral perfusion have not been studied up to now. We performed SPECT studies using 99mTc-(d,l)-hexamethyl-propylenaminoxim (HMPAO) as a tracer in 14 adult patients with moderate to severe OSA (AHI > 30/h; mean AHI 59.2 +/- 4.3). The injection of the tracer took place between 2:00 and 4:00 a.m. while repeated episodes of obstructive apnoea were detected by polysomnography during stage II sleep. Data acquisition took place at 7:30 a.m. All measurements were repeated some nights later under effective treatment with nCPAP. Visual analysis showed marked frontal hyperperfusion in 5 patients. When regional perfusion indices were calculated for 32 regions of interest statistical analysis showed reduced perfusion of the left parietal region. These changes were completely reversed by effective nCPAP therapy. These data suggest that OSA is associated with reversible changes of regional cerebral perfusion. The underlying pathophysiologic mechanisms are matter of speculation so far. There might be an apnoea-associated effect of local vascular autoregulation mechanisms acting to compensate systemic blood flow alterations or blood gas changes in OSA. The observed frontal hyperperfusion might be caused by activation of the frontal lobe by repetitive cortical arousals.

Myocardial damage assessed by indium-111-antimyosin: correlation with persistent enteroviral ribonucleic acid in dilated cardiomyopathy.

The persistence of enteroviral ribonucleic acid (RNA) in the myocardium has been implicated as a pathogenetic factor in idiopathic dilated cardiomyopathy. Enteroviral persistence may lead to myocardial cell membrane damage, resulting in increased uptake of antimyosin antibodies. To further evaluate this hypothesis, a direct comparison of myocardial antimyosin uptake with the presence of enteroviral RNA was performed in ten patients (one female, nine male; 53+/-8 years) with chronic dilated cardiomyopathy. Planar antimyosin images were obtained 48 h after the injection of indium-111-labelled antimyosin Fab. Using a region of interest technique, the heart to lung uptake ratio (HLR) was calculated as a semiquantitative parameter of myocardial tracer uptake. Cardiac catheterization was performed to assess left ventricular function and to obtain myocardial biopsy samples. In the biopsy samples, gene amplification by polymerase chain reaction (PCR) was used to specifically detect enteroviral RNA. In the ten patients, the left ventricular ejection fraction was 39%+/-11% and the end-diastolic volume 131+/-46 ml/m2. The HLR was 1.72+/-0.21 and showed no correlation with functional parameters. In two patients with a positive PCR consistent with persisting enteroviral RNA, the HLR was not higher than that in eight patients with a negative PCR (1.46+/-0. 18 vs 1.78+/-0.18, respectively). These results suggest that increased uptake of 111In-antimyosin in chronic idiopathic dilated cardiomyopathy cannot be explained by pure persistence of enteroviral RNA. Other pathogenetic factors such as myocardial autoantibodies or microvascular spasm may be responsible for myocyte membrane damage detected by antimyosin.

Distribution of radiolabelled anti-CA125 monoclonal antibody OC125-F(ab)2-fragment following resection guided by antibodies (REGAJ) in ovarian cancer patients.

Ovarian cancer is a highly malignant tumor of mainly postmenopausal women. The long-term prognosis of this malignancy is largely determined by micrometastasis present at the time of second-look surgery. In general, patients face a poor outcome. New radio-immunoscintigraphic methods to target tumor tissue specifically via antigen-antibody binding were developed. However, few studies so far investigated the pattern of in vivo distribution of radiolabelled mAbs and/ or the specificity of antigen-antibody interaction. In this study we examined the immunological interaction and distribution of 131l-OC125-F(ab')2-fragment, an anti-CA-125 mAb, in patients with CA-125 positive ovarian malignancies. Sixteen patients with primarily CA-125 positive gynecological tumors underwent REGAJ surgery. Biopsies of tumor tissue and not tumor infiltrated tissue, serum, and ascites were sampled during or prior to REGAJ surgery, respectively. After preparation of tissue cytosols, samples were assessed for CA-125 and radioactive uptake. By radiochromatography immunological analysis for presence of the target antigen CA-125, the mAb 131l-OC125-F(ab')2-fragment, and immune complexes was performed on different specimen. CA-125 concentrations were higher in serum samples, ascites, and malignant tissue biopsies of malignoma patients compared to those without signs of malignant disease. CA-125 was higher in the tissue cytosol than in the cell membrane fraction. Gel filtration revealed CA-125 with moieties of 75,000 to > 600,000 d. Accumulation of radioactivity was more frequently associated with the presence of unbound 131l-OC125-F(ab')2-fragment or high molecular weight immune complexes. Radioactive uptake, however, was not confined to tissue of high CA-125 expression. Moreover, both immune complex as well as 131l-OC125-F(ab')2-fragment could be isolated from cytosols of tissue not infiltrated by tumor cells as well. Our study demonstrates that the majority of CA-125 is located intracellularly and thus inaccessible to 131l-OC125-F(ab')2-fragment per se. The uptake of 131l-OC125-F(ab')2-fragment into the cytosol of tumor-free and malignant tissue samples prompts us to speculate that certain mechanisms for antigen-specific and nonspecific cellular trafficking of mAbs do exist. We present a model to explain our observations.

Dopamine and depression--striatal dopamine D2 receptor SPECT before and after antidepressant therapy.

Ten unmedicated and ten medicated patients with major depression and ten controls were investigated with IBZM-SPECT. The ten unmedicated patients were reinvestigated after treatment with tricyclic antidepressants. Dopamine D2 receptor occupancy was not different between patients and controls, or medicated and unmedicated patients. IBZM binding was increased in four patients with psychomotor retardation. Antidepressant therapy led to a decrease in IBZM binding in the five improved patients. Dopamine D2 receptor binding remained unchanged in nonresponders. It is concluded that striatal dopamine D2 receptor binding is not changed in depression or by tricyclic antidepressants; however, it is affected by psychomotor activity. The changes observed might be the result of increased tonic dopamine release in the basal ganglia, but several other explanations exist.

99m-Tc-HMPAO-SPECT in diagnosis of early cerebral vasculitis.

The objective of this study was to evaluate whether mild neurological symptoms suggestive of neuropsychiatric involvement may be associated with cerebral perfusion defects as detected by functional brain imaging with 99m-Tc-HMPAO-SPECT (single photon emission computed tomography). SPECT analysis for the early detection of central nervous system (CNS) involvement was evaluated in 40 consecutive patients with systemic vasculitis or with Sneddon's syndrome. Of these, 18 patients showed overt neuropsychiatric symptoms, so-called major symptoms (e.g. motoric or sensible defects); 6 had mild symptoms like headache or cognitive disorders, so-called minor symptoms: 16 patients did not present with any of these symptoms. SPECT abnormalities were detected in 16 of the 18 patients with overt neuropsychiatric symptoms (89%). Five of the 6 patients with minor symptoms (83%) and 5 of the 16 patients without neurological symptoms (31%) also had SPECT abnormalities. There was no relation to disease activity or duration. We concluded that the high sensitivity of SPECT (87.5%) in detecting perfusion abnormalities among the evaluated group of patients indicates its suitability for early diagnosis of vasculitic CNS involvement.

Reduced benzodiazepine receptor binding in panic disorders measured by iomazenil SPECT.

We compared a group of nine patients with panic disorder (DSM-III-R) and depression with a matched control group of nine dysthymic patients without a previous or actual history of panic attacks or anxiety with iomazenil SPECT (single photon emission computed tomography) to evaluate panic-related abnormalities of the benzodiazepine receptor complex. The panic group had a significant decrease (p < .05, U-tests) in the regional activity index (RAI) in the following regions after 2 h: lateral inferior temporal lobes, right and left, medial inferior temporal lobes, left, inferior frontal lobes, right and left. All other regions investigated were not significantly different. The findings may be due to either regional blood flow differences or benzodiazepine receptor effects. The hypothesis that the effects are due to altered blood flow is confirmed to some extent by similar findings in the scans acquired after 10 min. Only the hypoactivity in the left lateral temporal region seemed to be independent of reduced blood flow in panic disorders.

Single photon emission computerized tomography assessment of cerebral dopamine D2 receptor blockade in depression before and after sleep deprivation--preliminary results.

The antidepressant properties of total sleep deprivation (TSD) have been well established. There is some evidence that TSD may improve depression by altering central dopamine (DA) function. We therefore studied five depressed TSD responders and five TSD nonresponders after sleep and after TSD and five controls after sleep with IBZM single photon emission computerized tomography (SPECT). Responders showed a significant decrease (Wilcoxon--test p < 0.05) of relative basal ganglia D2 receptor occupancy after TSD compared to nonresponders (change score responders versus nonresponders p < 0.05, U-test). The data are interpreted as a sign of an enhanced DA release in responders. The results confirm previous hypotheses of dopaminergic involvement in the therapeutic action of TSD and indirectly support a dopamine hypotheses of depression.

Investigation of parasympathetic and sympathetic cardiac innervation in diabetic neuropathy: heart rate variation versus meta-iodo-benzylguanidine measured by single photon emission computed tomography.

In diabetic neuropathy disturbed autonomic cardiac innervation is associated with shortened life expectancy. Sympathetic dysfunction is likely to play a role in cases of cardiac death. The quantitative uptake of the radiopharmaceutical iodine-123-meta-iodo-benzylguanidine (MIBG) can be measured by single photon emission computed tomography (SPECT). It is an index of the functional integrity of sympathetic neurones in the heart. The respiratory heart rate variation--as assessed by a computerized device--reflects mainly parasympathetic cardiac innervation. In 25 diabetic patients and 19 healthy subjects MIBG-SPECT and heart rate variation tests were carried out. MIBG scans in all normal subjects showed homogeneous uptake of activity. In 12 out of 25 patients at least two heart rate variation tests were abnormal. MIBG-SPECT was more sensitive (abnormal in 17 out of 25). The lack of correlation between MIBG-SPECT results and spectral analysis of heart rate variation suggest that spectral analysis alone should not be regarded as an indicator of sympathetic cardiac innervation.

Increased limbic blood flow and total sleep deprivation in major depression with melancholia.

Single photon emission computed tomography (SPECT) with technetium-99m-d,l-hexamethyl-propylene amine oxime (99Tcm-HMPAO) was carried out in 20 melancholic patients before and after total sleep deprivation. Findings in 11 responders to total sleep deprivation (defined by > or = 40% improvement on the Hamilton Rating Scale for Depression) were compared with findings in nine nonresponders. On the basis of a semiquantitative evaluation of SPECT findings, responders showed relative hyperperfusion before sleep deprivation in the right anterior cingulate cortex and in the right and left fronto-orbital cortex and basal cingulate gyrus. Responders who showed > or = 50% improvement also showed hippocampal overactivation before sleep deprivation. It is possible that limbic overactivation may characterize depressed responders to total sleep deprivation as a distinct subtype. Another possibility is that the pattern of limbic hyperactivation reflects the increased number of bipolar patients in the responder group, with response to total sleep deprivation being only a covariate of this bipolar-unipolar distinction.

R peak time prolongation and R peak delay in leads I, V5, or V6. Diagnostic values as signs of myocardial dysfunction in chronic mitral incompetence.

On the assumption that maximum R peak time prolongation in the left-sided leads I, V5, or V6 and its time relationship to the S peak time of the maximum S amplitude in leads V1, V2, or V3 (representing dorsally directed forces of ventricular depolarization) could indicate the extent of left ventricular volume overloading and possibly left ventricular systolic function, these variables and the preoperative findings of angiocardiography were compared between patients with chronic mitral incompetence who, late after corrective valve surgery, had either well-preserved radionuclide left ventricular ejection fraction (group 1, n = 36) or radionuclide left ventricular ejection fraction below 50% (group 2, n = 30). Before surgery, group 2 patients had a highly significant lower mean left ventricular ejection fraction, a highly significant greater mean end-systolic volume index, a significantly greater mean end-diastolic volume index, a significantly greater mean maximum R peak time in leads I, V5, or V6, and a significantly greater prolongation of the maximum R peak time above the S peak time in the right precordial leads, as compared with group 1. R peak times greater than 50 ms or the presence of R peak delay (maximum R peak time greater than the S peak time of the maximum right precordial S amplitude) yields less sensitive but highly reliable results in predicting radionuclide left ventricular ejection fraction below 50% with both specificity and positive predictive values of 100%. Thus, in chronic mitral regurgitation surgery should not be delayed if patients present these signs because they are specific markers of irreversibly impaired chamber function.