2D-echocardiography vs cardiac MRI strain using deep learning: a prospective cohort study in patients with HER2-positive breast cancer undergoing trastuzumab

Funding Acknowledgements

Type of funding sources: Private hospital(s). Main funding source(s): Promotiefonds Albert Schweitzer Hospital

Background

Subclinical cardiotoxicity due to trastuzumab could be recognized by repeated measurements of global longitudinal/radial strain (GLS/GRS) which could be performed with cardiac magnetic resonance (CMR) or two-dimensional speckle tracking echocardiography (2DE-ST). Although CMR is the gold standard for cardiac function evaluation, it is not used for cardiac monitoring. 2DE-ST might be a reasonable alternative. 

Purpose

To study the predictive value of early 2DE-ST for left ventricular ejection fraction (LVEF) changes during trastuzumab for HER2-positive breast cancer.

Methods

HER2-positive breast cancer patients receiving trastuzumab, with or without anthracycline, underwent 2DE-ST at baseline and after 3 and 6 months (m) trastuzumab. Cardiac magnetic resonance (CMR) imaging (with ST) was performed at baseline and 6m. We studied the correlation between 2DE-ST- and CMR-derived GLS and GRS. We then associated baseline and 3m 2DE-ST with later CMR-LVEF, and with cardiotoxicity, defined as CMR-LVEF <45% and/or absolute decline >10% during trastuzumab.

Results

47 patients were included. GLS measurements based on 2DE-ST and CMR showed weak correlation (Pearson’s r = 0.33; P = 0.041); GRS measurements were uncorrelated (r = 0.09; P = 0.979). 2DE-LVEF at baseline and 3m, and 2DE-STE-GLS at 3m were predictive of CMR-LVEF at 6m (Table 1). In contrast, the change in 2DE-ST-GLS at 3m was predictive of the change in CMR-LVEF at 6m, whereas the change in 2DE-LVEF was not. Importantly, the 11 patients (28%) who developed cardiotoxicity had larger 2DE-ST-GLS change at 3m than those who did not (median 5.2% versus 1.7%; odds ratio 1.81, 95% confidence interval 1.11–2.93; P = 0.016).

Conclusion

Although correlations between 2DE-ST and CMR are weak, ST-measurements appeared useful to improve the performance of 2DE in predicting LVEF changes after 6m of trastuzumab.

Table 1 2DE CMR-LVEF after 6m TZT Mean difference (95% CI) Change in CMR-LVEF after 6m TZT Mean difference (95% CI) Cardiotoxicity OR (95% CI) Before TZT LVEF, % 0.85 (0.42, 1.27)* 0.32 (-0.16, 0.80) 0.88 (0.75, 1.02) ST-GLS, % -0.42 (-1.31, 0.46) -0.28 (-1.14, 0.58) 1.13 (0.87, 1.46) 3 Months TZT LVEF, % 0.59 (0.30, 0.88)* 0.29 (-0.04, 0.61) 0.85 (0.74, 0.98)* ST-GLS, % -1.14 (-2.07, -0.19)* -0.62 (-1.54, 0.30) 1.36 (0.94, 1.84) Change at 3 months TZT LVEF, % 0.30 (-0.11, -0.71) 0.21 (-0.19, 0.61) 0.90 (0.80, 1.01) ST-GLS, % -1.17 (-2.14, -0.20)* -1.10 (-2.02, -0.18)* 1.81 (1.11, 2.93)* * P-value <0.05

A new diagnostic work-up for defining anemia etiologies: a cohort study in patients ≥ 50 years in general practices

Background

To study etiologies of anemia using an extensive laboratory analysis in general practices.

Method

An extensive laboratory analysis was performed in blood of newly diagnosed anemia patients aged ≥50 years from the general population in the city of Dordrecht area, the Netherlands. Eight laboratory-orientated etiologies of anemia were defined. Patients were assigned one or more of these etiologies on the basis of their test results.

Results

Blood of 4152 patients (median age 75 years; 49% male) was analyzed. The anemia etiology was unclear in 20%; a single etiology was established in 59%; and multiple etiologies in 22% of the patients. The most common etiologies were anemia of chronic disease (ACD) (54.5%), iron deficiency anemia (IDA) (19.1%) and renal anemia (13.8%). The most common single etiologies were IDA (82%) and ACD (68%), while the multiple etiologies most commonly included folic acid deficiency (94%) and suspected bone marrow disease (88%). Older age was associated with a lower incidence of IDA and a higher incidence of renal anemia. Mild anemia was more often associated with ACD and uncertain anemia, while severe anemia was mainly seen in patients with IDA.

Conclusion

Extensive laboratory analysis in anemic patients from the general population helped clarify the etiology of anemia and revealed many various combinations of etiologies in a significant proportion of patients. Age, sex and the severity of anemia are predictive of the underlying etiology.

Abstract P6-17-19: What to do with trastuzumab therapy after achieving radiological complete remission (rCR) in HER2+ metastatic breast cancer (MBC)?

Intro MBC is generally considered incurable, but patients with HER2+ disease treated with trastuzumab do relatively well and some have an exceptional durable response and survive over 10 years. We analyzed the clinical-pathological characteristics associated with long-term survival in patients with HER2+ MBC treated with trastuzumab. In addition, we studied the effect of stopping trastuzumab in case of rCR.

Methods We included all patients with HER2+ MBC treated with first- or second-line trastuzumab-based palliative therapy between January 2000 and December 2014 in 8 Dutch hospitals (Netherlands Cancer Institute, Erasmus Medical Center, Albert Schweitzer Hospital, Reinier de Graaf Hospital, Amphia Hospital, St. Antonius Hospital, Ikazia Hospital, Haga Hospital). Patients were identified through the Netherlands Cancer Registry and linkage with the institutes' tumor registries. Data was collected from medical records using case record forms. Primary endpoint was overall survival (OS), defined as first-date of MBC until death due to any cause. Kaplan-Meier survival estimates were calculated and multivariable Cox-regression models used to identify prognostic factors for improved survival. Time to progression (TTP) after achieving rCR for patients who continued and stopped trastuzumab and breast cancer specific survival were secondary outcomes.

Results We included 744 patients (median age 53, range 24-87). Median follow-up (FU) was 109 months (range 0-178). Clinical factors associated with improved survival in multivariable analyses were single-organ metastases, ER-positivity, no skin or liver metastases, no prior trastuzumab, local therapy of metastatic disease and achievement of rCR. In line with our first single center analyses1, achievement of rCR was the strongest predictor of improved survival (multivariable HR 0.30, 95%CI 0.20-0.46). RCR was observed in 71 patients (10%), of whom 60 had been treated with trastuzumab and chemotherapy, 9 with trastuzumab and hormonal therapy, and 2 with hormonal therapy. In patients with rCR the estimated 10-year OS was 53% versus 7% in patients who did not achieve rCR (p<0.001).

Thirty patients stopped trastuzumab after achieving rCR. Median time between onset of rCR and last gift of trastuzumab in these patients was 6 months (0-132). Twenty-one patients (70%) remain in complete remission after a median FU of 75 months (range 54-90) since onset of rCR. Nine patients experienced disease progression after a median time of 14 months (range 9-62) since last gift of trastuzumab. Of these, 8 patients died due to MBC and one again achieved an ongoing rCR. Out of 39 patients who continued trastuzumab after achieving rCR, 12 are in ongoing remission after a median FU of 71 months (range 51-91). In this group median TTP was 14 months (range 5-23).

Conclusion Achieving rCR is strongly associated with long-term survival in patients with HER2+ MBC. Seventy percent of patients who stopped trastuzumab after achieving rCR remained in remission, suggesting this can be an attractive approach in selected patients. External validation of these findings is required, however, as well as additional analyses to characterize the patients -and their tumors- who achieved rCR.

1 Steenbruggen, CancerRes 2017

Citation Format: Steenbruggen TG, Bouwer NI, Smorenburg CH, Rier HN, Jager A, Beelen KJ, ten Tije AJ, de Jong PC, Drooger JC, Holterhues C, Horlings HM, Sanders J, Levin M-D, Sonke GS. What to do with trastuzumab therapy after achieving radiological complete remission (rCR) in HER2+ metastatic breast cancer (MBC)? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-19.

Microbiological outcomes and antibiotic overuse in Emergency Department patients with suspected sepsis

OBJECTIVE

To study the presence of bacterial disease and antibiotic use in patients in the emergency department (ED) included in the local sepsis protocol.

METHODS

An observational retrospective cohort study. Adults aged > 18 years, presenting to the ED of a large teaching hospital, from 1 January to 1 June 2011, with more than two SIRS criteria and a clinical suspicion of sepsis were included.

RESULTS

Bacterial disease was suspected or confirmed in only 71% of all the patients with suspected sepsis (2008 definition) and consequently treated with antibiotics. Most of these patients (58%) suffered from systemic inflammatory response syndrome (SIRS) without signs of organ dysfunction, hypotension or hypoperfusion. Despite absence of bacterial disease in 29% of the patients after rigorous diagnostics, median antibiotic treatment in this group was still seven days (IQR 4-10).

CONCLUSIONS

Standard sepsis detection using SIRS criteria and clinical suspicion identified patients with suspected or confirmed bacterial disease in 71% of the cases. A significant proportion of patients were exposed to prolonged antibiotic use without proof of bacterial disease. This study illustrates the difficulties in correctly identifying bacterial disease and sepsis, and shows that overuse of antibiotics may be the consequence.

[Sphincter Ochsner dyskinesia as a cause of superior mesenteric artery syndrome]

OBJECTIVE

to investigate the pathological physiology of superior mesenteric artery syndrome (SMAS).

MATERIAL AND METHODS

We selected 35 articles devoted to SMAS, which were published from 1990 to 2014, and performed radiometric analysis of X-rays, CT scans and MRI slices found in these articles. In pictures the narrowing in the third part of the duodenum was measured from the boundary of the expanded segment to the level of the superior mesenteric artery (SMA).

RESULTS

Only in 6 (17%) of 35 cases the narrowing portion of duodenum was located directly between aorta and SMA, and its length was about 1 cm. In the remaining 29 cases, the beginning of the narrow segment was 2.5-4.6 cm (average 3.30 ± 0.15 cm) proximal to SMA, ie, most of the narrowed duodenum was out of aortomesenteric angle. Location and length of the narrowed segment of duodenum corresponded to the location and length (3.2 ± 0.15 cm) (P > 0.2) of the functional Ochsner sphincter.

CONCLUSION

These data indicate that in most cases of SMAS the sphincter Oclisner dyskinesia causes the disease. It is likely that the disease is triggered by heavy stressful conditions that cause a sharp and sustained reduction in the pH of gastric secretions, which in turn leads to the spasms of the sphincter Ochsner. With time this condition progresses to hypertrophy of the contracted wall of the duodenum with subsequent replacement of the muscle fibers by connective tissue. This can lead to the rigidity of the wall.

PATHOGENETIC SIGNIFICANCE OF DYSKINESIA OF THE SPHINCTER OF OKSNER IN THE DEVELOPMENT OF THE SYNDROME OF THE SUPERIOR MESENTERIC ARTERY

The goal of this study is to investigate the pathological physiology of superior mesenteric artery syndrome (SMAS).

MATERIALS AND METHODS

We selected 35 articles devoted to SMAS, which were published from 1990 to 2014, and performed radiometric analysis of X-rays, CT scans and MRI slices found in these articles. In pictures the narrowing in the third part of the duodenum was measured from the boundary of the expanded segment to the level of the superior mesenteric artery (SMA).

RESULTS

Only in 6 (17%) of. 35 cases the narrowing portion of duodenum was located directly between aorta and SMA, and its length was about 1cm. In the remaining 29 cases, the beginning of the narrow segment was 2.5-4.6 cm (average 3.30 ±0.15 cm) proximal to SMA, ie, most of the narrowed duodenum was out of aortomesenteric angle. Location and length of the narrowed segment of duodenum corresponded to the location and length (3.2 ± 0.15 cm) (P> 0.2) of the functional Ochsner sphincter.

CONCLUSION

These data indicate that in most cases of SMAS the sphincter Ochsner dyskinesia causes the disease. It is likely that the disease is triggered by heavy stressful conditions that cause a sharp and sustained reduction in the pH of gastric secretions, which in turn leads to the spasms of the sphincter Ochsner. With time this condition progresses to hypertrophy of the contracted wall of the duodenum with subsequent replacement of the muscle fibers by connective tissue. This can lead to the rigidity of the wall.

[Duodenal motility in norm and in some diseases. Hypothesis]

AIM

to investigate the duodenal motility on the basis of radiological studies.

PATIENTS AND METHODS

We tested our hypothesis that sphincters of Kapandji and Ochsner are contracted in response to stimulation of duodenum by hydrochloric acid. These sphincters are not found in standard X-ray studies because barium does not contain hydrochloric acid when it coming from the stomach into the duodenum. The retrospective analysis of radiological studies of the upper digestive tract of 116 patients aged 55 to 92 years was done. The first group consisted of 83 patients in whom the study was conducted using conventional barium suspension. The second group consisted of 8 patients who received 200 ml of barium with the addition of 3 grams of vitamin C. The third group was comprised of 25 patients with primary duodenal diverticula. The fourth group included radiographs from 35 articles devoted to the superior mesenteric artery syndrome (SMAS). We measured the width of the duodenum and the length of the sphincters on these radiographs.

RESULTS AND CONCLUSION

We found an important role of the sphincters (bulbo-duodenal, Kapandji, Ochsner) in the duodenal physiology. On this basis, we proposed the hypothesis defining basic patterns of the duodenal motor function. Proposed hypothesis allows us to understand how the duodenum performs important functions and provides new avenues for understanding the pathogenesis of acquired diseases of the upper gastrointestinal tract. The different forms dyskinesia of these sphincters play an important role in the pathogenesis of the SMAS, primary duodenal diverticula and sphincter Oddi dyskinesia.

GASTRIC MOTILITY HYPOTESIS

The publication is based on a retrospective analysis of 344 radiological studies of the upper digestive tract and analysis of the literature. We propose the hypothesis of the gastric motility, based on the following points: 1) The gastric cardia is the intra-abdominal portion of the lower esophageal sphincter (LES). Its tone increases in response to the increasing pressure in the stomach. 2) in gastroesophageal reflux disease (GERD), the cardia cannot withstand the pressure and subsequently opens. Depending on the degree of insufficiency of the LES and the force applied during provocative test, angular deformity of the stomach appears, due to the shortening of LES as well as a downsizing of the gas bubble in the stomach; 3) Pyloric sphincter (PS) is a true sphincter. Evacuation from the stomach is the result of the opening of the PS due to increase of antral pressure above the "threshold" level; 4) The evacuation starts in the upright position, when the liquid chyme above PS creates hydrostatic pressure above the threshold; 5) When hydrostatic pressure is reduced below the threshold level or in the recumbent position the antral pressure is created by the clamping of deep peristaltic wave and formation of the closed antral cavity; 6) The portioned evacuation is provided in two ways; a) the volume of antral cavity corresponds to the volume of duodenal bulb; b) in upright position after filling of the duodenal bulb the postbulbar sphincter is closed, whereby the pressure in the bulb rises, which leads to a reflex contraction of the PS and cessation of the e stomach emptying.

THE PATHOGENESIS OF ACUTE APPENDICITIS. THE NON-SPECIFIC RESPONSE OF THE DIGESTIVE TRACT IN ACUTE INFLAMMATION IN THE ABDOMEN

Based on the analysis of literature and our own studies we propose hypothesis of the pathogenesis of acute appendicitis (AA), which differs from the following generally accepted provisions. Acute appendidtis develops as a result of immunological reaction and hyperplasia of the mucous membrane of the appendix. Frequency peaks related to age, sex, and seasonal changes of AA are due to increased excretion of sex hormones. Only a small percentage of cases of primary hyperplasia causes a complete occlusion of the lumen and destructive AA. Usually it is exposed to regression without causing the typical symptoms, but leaving the damaged nervous system and / or sclerotic changes that violate the peristalsis of the appendix. Faeces, lingering in appendix eventually harden, increasing in size and often get saturated with salts. In the next fit of hyperplasia, the walls are stretched over fecolithe, causing obstruction of the lumen, the formation of a closed cavity and the known mechanisms of inflammation. Inflammation leads to increased tone of the stomach and colon, but strong in the segments of intestine lay next to the A. This is accompanied by increased of the anal canal pressure. Increased tone of the digestive tract is a nonspecific response to acute inflammation. We can assume that the same reaction is observed at any localization of acute and chronic inflammation.

[Descending perineum syndrome in children: Pathophysiology and diagnosis]

OBJECTIVE

To propose a safer, simpler, and more exact method for the diagnosis of descending perineum syndrome (DPS).

MATERIAL AND METHODS

A total of 194 patients aged 5 days to 15 years were examined and divided into 2 groups: Group 1 consisted of 65 patients without anorectal anomalies (AA); Group 2 comprised 129 patients, including 66 children with functional constipation, 55 with AA and visible fistulas, who were preoperatively examined, and 8 patients with anorectal angle (ARA), who were postoperatively examined. All the patients underwent irrigoscopy that was different from standard examination in the presence of X-ray CT contrast marker near the anus.

RESULTS AND CONCLUSION

DPS is caused by puborectalis muscle dysfunction. A method was proposed to evaluate the status of the puborectalis muscle from the distance between the position of the ARA and the marker near the anus. This not only promotes an exacter estimate of DPS, but also allows refusal of defecography. The use of a barium enema with the minimum number of X-ray films decreases dose of ionizing radiation hazard and permits the use of this procedure not only in adults, but also in children with chronic constipation, fecal incontinence, and in AA for both pre- and postoperatively assessment of the causes of complications.

[Schatzki ring as a symptom of gastroesophageal reflux disease]

OBJECTIVE

To determine the importance of a symptom of Schatzki ring.

MATERIAL AND METHODS

The results of examining 95 patients aged 62-92 years with the symptoms of dyspepsia in the Netanya State Geriatric Center (Israel) in 1994-2004 were analyzed. Standard X-ray study of the upper digestive tract was complemented by provocation tests. The length of an X-ray-negative area (XNA) between barium in the esophagus and stomach and the width in the lower esophagus were measured.

RESULTS

Only 2 (2%) of the 95 patients were found to have normal function of the gastroesophageal junction (GEJ). Two patients with a drastic esophageal narrowing due to reflux esophagitis were excluded. The remaining (91) patients were divided into 2 groups. The width of the esophagus was less than 2 cm and 2 cm or more in 64 (70%) and 27 (30%) patients, respectively. In weak GEJ, there was esophageal dilatation above the XNA. When in a horizontal position, this portion of the esophagus evacuates its contents into the stomach as a result of ampullary function. It is proximally closed by contracting the functional proximal sphincter (PS). When the ampulla contracts, its pressure increases up to the threshold. This causes the XNA to be closed and the ampulla to inject its contents into the stomach. The wider was the ampulla, the shorter the XNA was. Schatzki ring was detected in 20 (22%) of the 91 patients with gastroesophageal reflux disease (GERD). It was always at the level of the PS.

CONCLUSION

The so-called sliding esophageal hernia is an esophageal ampulla measuring more than 2 cm in wide. The presence of the esophageal ampulla despite its size suggests that the GEJ is incompetent and GERD is present. Schatzki ring occurs at the level of the PS due to reflux esophagitis.

[The pathological physiology of the anorectal defects, from the new concept to the new treatment]

PURPOSE

To determine physiology of anorectal zone in norm and anorectal malformations (ARM) to optimize the surgical treatment.

MATERIAL AND METHODS

Examination of 119 patients were selected, including 65 children without anorectal pathology and 54 patients with ARM. We performed barium enema with radiopaque marker placed near the anus. The manometric study of anorectal area was done using intubation tube with an inflatable cuff.

RESULTS

The anal canal was detected in all of ARM patients with perineal and vestibular fistulas, as well as in most of the newborns without fistula. The well innervated internal anal sphincter (IAS) was located in the loop of the puborectal muscle (PRM) and connected to the levator ani muscle (LAM) which opens the anal canal during defecation. Anterior and posterior sagittal approaches use IAS excision, with PRM damage and cutting off the LAM from IAS, which leads to incontinence and/or chronic constipation.

CONCLUSION

We describe two surgical approaches that allow preservation of all elements of the anal canal resulting in a normal post-operative continence and defecation.

[Pathological physiology of gastroesophageal reflux disease. Hypothesis (Literature review)]

Currently prolonged pH-monitoring is considered as Gold standard for diagnosis of Gastro Esophageal Reflux Disease (GERD). Criteria and norms based on prolonged pH-monitoring were the basic concepts of pathophysiology of GERD. For example, it is accepted that esophageal hernia (EG) can be present without GERD, as well as GERD without EG. X-ray diagnosis compared to the pH- monitoring has a low sensitivity (70%) and specificity (74%). Meanwhile, in recent decades, it has been found that the pH-metry is not effective in a non-erosive reflux disease. We figured that the criteria and norms of pH-monitoring are not accurate. The purpose of this study is to determine the radiological norms of gastroesophageal junction (EGJ) and, to clarify the pathological physiology of GERD according to the new criteria and analysis of the literature.

MATERIAL AND METHOD

The analysis of the survey of 452 patients was done. Among them were 263 children aged from 1 day to 15 years who have applied to the Belarusian Center of Pediatric Surgery (BCPS) in 1983-1987 and 189 patients aged 15-92 years surveyed in the BCPC, as well as in the Government Geriatric Center (Israel) in 1994-2004. The standard radiography of the upper digestive tract was supplemented by provocative tests. In 21 children and 36 adults survey was carried out to locate space-occupying lesions of the chest or abdomen. Other patients had symptoms of GERD.

RESULTS

The 21 children and 17 of 34 adult patients without of GERD symptoms had the same radiographic picture, indicating of the normal LES function: the width of the esophagus was the same all over and no more than 1.5 cm; in a horizontal position a peristaltic wave opens the LES and pushes its contents into the stomach without delay, despite the provocative tests. In 15 out of 34 adults with no symptoms of GERD radiographic findings show signs of LES weakness. In these patients, with a mild GERD, abdominal compression caused contraction of the GEJ with length of (3.60 +/- 0.8 cm) in adults which corresponds to the length of the LES, according to the manometric studies. A rounded cavity (phrenic ampoule) is formed above the contracted LES when the functional'proximal sphincter' (PS) is closed cranially. When, during the am ampoule contraction the pressure in it reaches a threshold level, LES is opened, and the ampoule injects its contents into the stomach. Inflammation of the esophageal wall leads to the gradual ampoule expansion. With a width of the ampulla 2 cm and more we found no evidence of the displacement of the stomach into the chest cavity. The radiological symptoms of GERD are described, the identification of which at rest and during provocation, can be used for grading the antireflux function impairment of LES.

CONCLUSION

1. In GERD the last peristaltic wave expands, forming a phrenic ampoule, which is closed cranially by the PS. 2. The width of the ampoule is proportional to the stages of GERD. This means that ampoule as well as the so-called esophageal hernia are symptoms of GERD. 3. During the ampoule formation the inner surface of it increases by at least to 11 cm2. The deficit of the mucosa is compensated by the motion of the mucosa from GEJ. The shortening of the longitudinal muscle during the ampulla contraction does not significantly affect the length of the esophagus. 4. Transient LES relaxation is caused by a deficiency of the LES capacity.

[The method of radiographic examination anorectal area]

PURPOSE

Puborectal muscle (PRM) plays an important role in the continence. Its function is impaired in chronic constipation, fecal incontinence, especially after anorectal surgery. Assessment of PRM condition by the measurement of anorectal angle is not precise, the defecography requires special equipment and is associated with high doses of radiation. The purpose of this study is to propose another method of evaluation of anorectal function free of the above mentioned disadvantages.

MATERIAL AND METHODS

The analysis of 475 studies of patients of all ages, including 79 without pathology anorectal area and 396 patients with different pathologies was done. They were examined by a method that differs from the usual barium enema by placing of radiopaque marker near the anus.

RESULTS AND DISCUSSION

The weakness of PRM manifested by penetration of barium into the anal canal behind the tip of the enema. The prominent shortening of the anal canal, compared to age-related normal figures indicates the PRM failure. The finding of the anal canal shortening has the same diagnostic value as the perineum distendion revealed by defecography. The proposed method is simple, accurate, and does not apply large dose of radiation.

Enteroviral encephalitis in a patient with a marginal zone lymphomatreated with rituximab

A 64-year-old woman with a progressive marginal zone lymphoma for which she had received induction therapy with six courses of rituximab and fludarabine presented with fever while receiving maintenance therapy with rituximab. In addition to the fever she complained of nausea, vomiting, weight loss and fatigue. After an extensive diagnostic procedure no cause was found for the fever. Finally, additional testing showed a positive polymerase chain reaction (PCR) for enterovirus in the cerebrospinal fluid and faeces. Because the immunoglobulin G level of our patient was 4.06 g/l (normal values 5.2 to 16 g/l), she was treated with intravenous immunoglobulins (IVI g) weekly with the goal to maintain an IgG level above 10 g/l. This resulted in a significant rise in anti-enteroviral antibodies from 10 IE /ml to 106 IE /ml. One month after treatment with IVI g, while withholding the rituximab, the PCR for enterovirus on faeces was negative and antibodies to the enterovirus in the serum had returned to normal levels. Rituximab can cause a prolonged B-cell deficiency resulting in hypogammaglobulinaemia. We believe that treatment with ritxumab may have played a significant role in the development of this rare central nervous system infection.

Disseminated intravascular coagulation and a negative D-dimer test

The diagnosis of disseminated intravascular coagulation (DIC) requires the presence of a fibrin-related marker. D-dimer is frequently used in clinical practice as a fibrin-related marker. We present a case of paraneoplastic DIC with a false-negative D-dimer test. Repeating the test using a different D-dimer assay as well as the measurement of other fibrinolysis markers confirmed the diagnosis of DIC.

The value of crossmatch tests and panel tests as a screening tool to predict the outcome of platelet transfusion in a non-selected haematological population of patients

BACKGROUND AND OBJECTIVES

Alloantibodies against platelets can be detected by using different laboratory tests. Most of these tests, which use panel cells or antigens as a target, perform poorly in non-selected haematological patients. In relation to these tests, a crossmatch test of transfused platelets and patient's serum may be viewed as the standard and may be superior in predicting donor platelet destruction by alloimmunization.

MATERIALS AND METHODS

In 95 randomly selected thrombocytopenic patients with haematological malignancies, who were receiving leucodepleted blood products, 184 serum samples were studied in an in vitro crossmatch test by using the technique of the platelet immunofluorescence test (crossmatch-PIFT), in an in vivo crossmatch test detecting in vivo binding of immunoglobulins to transfused platelets according to the PIFT technique (in vivo-PIFT), in the indirect PIFT using five random donors as a target (panel-PIFT) and in an enzyme linked immunosorbent assay using immobilized human leucocyte antigens (HLAs) of 100 standardized donors (ELIHLA). The results of all these methods were related to the recovery at 1 and 16 h post-transfusion.

RESULTS

The results of the crossmatch-PIFT were not associated with platelet recovery at 1 and 16 h after transfusion. Even in a subgroup of patients, in whom predefined clinical factors were excluded, no association with platelet recovery was found. The results of the crossmatch-PIFT correlated with those of the in vivo-PIFT (P = 0.02); however, 35 (19%) discrepant results were identified between these tests. The results of the crossmatch-PIFT were not related to the panel-PIFT (P = 0.25), but did relate to those of the ELIHLA (P = 0.02), still revealing 36 (20%) discrepant results. None of the in vivo-PIFT, the panel-PIFT or the ELIHLA was associated with platelet recovery after 1 h, whilst only a positive panel-PIFT was associated with poor platelet recovery at 16 h after transfusion (P = 0.03).

CONCLUSIONS

In a population at low risk for alloimmunization, the correlation of test outcome and platelet recovery is poor. None of these crossmatch tests or screening tests was identified as superior to any other in this population.

Noise in gene expression as the source of non-genetic individuality in the chemotactic response of Escherichia coli

A deterministic computer model of the signal transduction pathway mediating bacterial chemotaxis was used to examine the variation in both unstimulated swimming behaviour and adaptation time to stimuli in clonal populations of cells. Copy numbers of proteins in the pathway were computed from a simplified model of transcription and translation that predicts greater-than-Poissonian statistics. Simulated and experimental individuality data could be brought into good agreement on varying the noise strength of the protein copy number distributions. In the simulations, all the proteins in the pathway are involved to a significant degree in the appearance of phenotypic diversity, although there is a modest decrease in influence with increasing copy number.

Two patients with acute thrombocytopenia following gold administration and five-year follow-up

Thrombocytopenia is a well-known side effect following intramuscular gold therapy in patients with rheumatoid arthritis. Thrombocytopenia may occur at any time and it can be irreversible and sometimes fatal despite cytotoxic or immunosuppressive therapy. We describe two patients who presented with haemorrhagic diathesis on the day after the administration of aurothioglucose. The thrombocytopenia in these patients was caused by aurothioglucose-induced antibody-mediated platelet destruction. Both patients made an uneventful recovery and the platelet count returned to normal within several weeks without further treatment. Antibody-detecting tests were repeated five years later and could not demonstrate the presence of antibodies. Also after incubation with aurothioglucose no antibodies could be demonstrated.

Immune and nonimmune causes of low recovery from leukodepleted platelet transfusions: a prospective study

Alloantibodies against HLA antigens can be reduced by applying leukodepletion to transfusions. Because the importance of immunological and nonimmunological causes of poor platelet transfusion results using leukodepleted transfusions is not clear, we conducted a prospective study in an unselected patient population receiving leukodepleted transfusions. In 97 patients with hematological malignancies, 181 random leukodepleted platelet transfusions were studied for immunological causes of poor platelet transfusion results by calculating the odds ratio of four different screening tests for a low platelet recovery. Nonimmune causes were also studied by calculating the odds ratio of the most prevalent nonimmune causes for a low platelet recovery. No single screening test showed an association with recovery after 1 and 16 h following a platelet transfusion. The combination of a positive enzyme-linked immunosorbent assay (ELISA) and platelet immunofluorescence test (PIFT) or a combination of a positive lymphocyte immunofluorescence test (LIFT) and PIFT, demonstrating an association with a low platelet recovery after 16 h, was present in 2% of all platelet transfusions. Of nonimmune causes, splenomegaly and storage time of platelets for more than 3 days were associated with low platelet recovery after 1 h and 16 h of being present in 29% and 47% of all platelet transfusions, respectively. Immunological causes account for a small proportion of poor platelet transfusion results compared to nonimmunological causes in a nonselected patient population receiving leukodepleted transfusions.

Visual scoring versus histogram subtraction of in vivo binding of immunoglobulins against platelets after transfusion

BACKGROUND

We developed a technique, in vivo binding of immunoglobulins in the platelet immunofluorescence test (IVBI-PIFT), that detects immunoglobulins bound in vivo to transfused platelets. The visually scored results of this technique, however, are susceptible to interobserver variation. We describe a more objective method to generate results in IVBI-PIFT.

METHODS

We studied 201 samples in 120 patients with hematologic malignancies in the IVBI-PIFT. Histogram subtraction, i.e., fluorescence (anti-immunoglobulin G and fluorescein isothiocyanate) histogram before platelet transfusion subtracted from the histogram after platelet transfusion, was compared with visual scoring (pattern 1: no enhanced fluorescence before and after transfusion; pattern 2: enhanced fluorescence before and after platelet transfusion; pattern 3: enhanced fluorescence before transfusion; pattern 4: enhanced fluorescence after transfusion, interpreted as alloimmunization). After histogram subtraction, the number of remaining events (events post substraction, EPS) and the mean amount of fluorescence of these remaining events (mean channel post substraction, MCPS) were used and compared with the visual scoring and with platelet survival after transfusion.

RESULTS

In 26 (13%) of the 201 samples studied in the IVBI-PIFT, fewer than three of five observers agreed on the visually scored pattern. In the 175 (87%) remaining samples, histogram subtraction showed a significant differentiation between pattern 4 and patterns 1 and 2 by using EPS, whereas patterns 4 and 3 were distinguished by using MCPS. The combination of EPS and MCPS differentiated best between pattern 4 and patterns 1, 2, and 3 (73% sensitivity, 96% specificity, 79% positive predictive value, and 95% negative predictive value). In contrast, the predictive value for platelet recovery after 1 and 16 h of pattern 4 from the visual scoring method and the results of histogram subtraction were poor.

CONCLUSION

This objective method of histogram subtraction correlated well with the visual scoring method of IVBI-PIFT.

Partially bridge-fluorinated dimethyl bicyclo[1.1.1]pentane-1,3-dicarboxylates: preparation and NMR spectra

Direct fluorination of dimethyl bicyclo[1.1.1]pentane-1,3-dicarboxylate, obtained from [1.1.1]propellane prepared by an improved synthetic procedure, furnished esters of 14 of the 15 possible bridge-fluorinated bicyclo[1.1.1]pentane-1,3-dicarboxylic acids, isolated by preparative GC. Calculated geometries reflect the substitution pattern in a regular fashion compatible with Bent's rules. Considerable additional strain is introduced into the bicyclo[1.1.1]pentane cage by polyfluorination; it is calculated to be as high as 33-35 kcal/mol for hexasubstitution. Three arrangements of the fluorine substituents are especially strain-rich: geminal, proximate, and W-related. The (1)H, (13)C, and (19)F NMR spectra exhibit a striking variety of chemical shifts and long-range coupling constants. These are in good agreement with results calculated with neglect of the bridgehead substituents for all of the chemical shifts by the GIAO-RHF/6-31G//RHF/6-31G and GIAO-RHF/6-31G//MP2/6-31G methods and for many of the coupling constants by the EOM-CCSD/6-311G//MP2/6-311G method. The proximate (4)J(FF) constants are particularly large (50-100 Hz) and show an inverse linear dependence on the calculated F-F distance in the range 2.43-2.58 A.

Molecular model of a lattice of signalling proteins involved in bacterial chemotaxis

Coliform bacteria detect chemical attractants by means of a membrane-associated cluster of receptors and signalling molecules. We have used recently determined molecular structures, in conjunction with plastic models generated by three-dimensional printer technology, to predict how the proteins of the complex are arranged in relation to the plasma membrane. The proposed structure is a regular two-dimensional lattice in which the cytoplasmic ends of chemotactic-receptor dimers are inserted into a hexagonal array of CheA and CheW molecules. This structure creates separate compartments for adaptation and downstream signalling, and indicates a possible basis for the spread of activity within the cluster.

Myocarditis and primary Sjögren's syndrome

We describe congestive heart failure caused by autoimmune myocarditis in a patient with primary Sjögren's syndrome. Only after corticosteroids were given did the symptoms and laboratory abnormalities disappear.

Platelet-bound immunogloblins before and after platelet transfusion: measurement of in vivo binding

In routine tests to investigate immunological mechanisms as a cause for enhanced destruction of transfused platelets; serum from the patient is tested against a panel of donor lymphocytes and platelets to demonstrate the presence of antibodies against HLA or platelet specific antibodies. Here we describe a flow cytometric technique in which in vivo binding of immunoglobulins (Ig) is measured. By comparing the histograms of the platelet suspensions before and after transfusion, four different patterns were obtained: no Ig binding before and after transfusion (pattern 1), pre-existent Ig binding (patterns 2 and 3) or preferential Ig binding to the transfused platelets (pattern 4). This technique was tested in 164 random platelet transfusions and 34 HLA-matched platelet transfusions. A statistically significant association was found between pattern 1 and a negative result of the indirect platelet immunofluorescence test for the detection of antibodies in the serum taken before the transfusion studied or a good platelet recovery and between pattern 4 and a positive indirect platelet immunofluorescence test or a low platelet recovery.

Design of organic molecules with large two-photon absorption cross sections

A strategy for the design of molecules with large two-photon absorption cross sections, delta, was developed, on the basis of the concept that symmetric charge transfer, from the ends of a conjugated system to the middle, or vice versa, upon excitation is correlated to enhanced values of delta. Synthesized bis(styryl)benzene derivatives with donor-pi-donor, donor-acceptor-donor, and acceptor-donor-acceptor structural motifs exhibit exceptionally large values of delta, up to about 400 times that of trans-stilbene. Quantum chemical calculations performed on these molecules indicate that substantial symmetric charge redistribution occurs upon excitation and provide delta values in good agreement with experimental values. The combination of large delta and high fluorescence quantum yield or triplet yield exhibited by molecules developed here offers potential for unprecedented brightness in two-photon fluorescent imaging or enhanced photosensitivity in two-photon sensitization, respectively.

Receptor clustering as a cellular mechanism to control sensitivity

Chemotactic bacteria such as Escherichia coli can detect and respond to extremely low concentrations of attractants, concentrations of less than 5 nM in the case of aspartate. They also sense gradients of attractants extending over five orders of magnitude in concentration (up to 1 mM aspartate). Here we consider the possibility that this combination of sensitivity and range of response depends on the clustering of chemotactic receptors on the surface of the bacterium. We examine what will happen if ligand binding changes the activity of a receptor, propagating this change in activity to neighbouring receptors in a cluster. Calculations based on these assumptions show that sensitivity to extracellular ligands increases with the extent of spread of activity through an array of receptors, but that the range of concentrations over which the array works is severely diminished. However, a combination of low threshold of response and wide dynamic range can be attained if the cell has both clusters and single receptors on its surface, particularly if the extent of activity spread can adapt to external conditions. A mechanism of this kind can account quantitatively for the sensitivity and response range of E. coli to aspartate.

Origins of individual swimming behavior in bacteria

Cells in a cloned population of coliform bacteria exhibit a wide range of swimming behaviors--a form of non-genetic individuality. We used computer models to examine the proposition that these variations are due to differences in the number of chemotaxis signaling molecules from one cell to the next. Simulations were run in which the concentrations of seven gene products in the chemotaxis pathway were changed either deterministically or stochastically, with the changes derived from independent normal distributions. Computer models with two adaptation mechanisms were compared with experimental results from observations on individuals drawn from genetically identical populations. The range of swimming behavior predicted for cells with a standard deviation of protein copy number per cell of 10% of the mean was found to match closely the experimental range of the wild-type population. We also make predictions for the swimming behaviors of mutant strains lacking the adaptational mechanism that can be tested experimentally.

Localization of AMPA-selective glutamate receptors in the auditory brainstem of the barn owl

AMPA receptor subunit-specific antibodies were used to determine if the distribution of excitatory amino acid receptors in the owl's auditory brainstem and midbrain nuclei reflected specializations for temporal processing. Each auditory nucleus displays characteristic levels of immunostaining for the AMPA receptor subunits GluR1-4, with high levels of the subtypes which exhibit rapid desensitization (GluR4 and 2/3). In the auditory brainstem, levels of GluR2/3 and GluR4 were very high in the cochlear nucleus magnocellularis and the nucleus laminaris. The different cell types of the cochlear nucleus angularis and the superior olive were characterized by heterogeneous GluR2/3 and 4 immunostaining. GluR1 levels were very low or undetectable. In the lemniscal nuclei, most neurons contained low levels of GluR1, and dense GluR2/3 and GluR4 immunoreactivity, with high levels of GluR4 in the dendrites. Levels of GluR4 were higher in the anterior portion of the ventral nucleus of the lateral lemniscus. The divisions of the inferior colliculus could be distinguished on the basis of GluR1-4 immunoreactivity, with high levels of GluR4 and moderate levels of GluR1 in the external nucleus. No major differences were observed between the pathways for encoding time and sound level cues.

[Diagnosis and treatment of ectopy of the anal canal]

An analysis of findings of clinical and ++roentgenological examinations of 55 patients with ectopy of the anal canal prior to operation and 68 patients after correction of the defect has shown that secondary megacolon developed in proportion with the age and degree of the outlet opening stenosis and there appeared injuries of elements of the normally formed anal canal. The authors described their original many-steps operation of the formation of the anus which allows all elements of retaining feces to be preserved. The amount of good long-term results increased from 22-26% up to 75% as compared with those of operations after Stone.

[Roentgeno-functional studies in ectopia of the anal canal in children]

Analysis of x-ray data on 70 pediatric patients aged one day-15 yrs, was performed. In 55 cases the investigation was conducted before the correction of ectopia of the anal canal, in 11 cases after the previously described operation for forming the anal orifice (FAO), in 4 cases there was stenosis of the anal orifice without ectopia. Radiograms performed during irrigoscopy and (or) with a Foley catheter were assessed. Weakening and then complete incompetence of the puborectal muscle, determining incontinence of feces, were shown to be proportional to age and a degree of stenosis of the colon orifice. A necessity of radical operation in the second half-year of the life or measures to ensure adequate bowel evacuation were shown.

[Diagnosis and surgical treatment of gastroesophageal reflux in children]

Results of observations examination and treatment of 115 children with gastroesophageal reflux aged from 3 days to 14 years are described. Great importance of special methods of examination was shown. Results of using the roentgenological method, fibroesophagogastroscopy with biopsy of the esophagus, manometry and electromyography of the esophagus are presented. Specific features and results of the surgical treatment of the disease are described.