MRI of cystic fibrosis lung manifestations: sequence evaluation and clinical outcome analysis

AIM

To evaluate different magnetic resonance imaging (MRI) sequences for diagnosis of pulmonary manifestations of cystic fibrosis (CF) in comparison to chest computed tomography (CT), including an extended outcome analysis.

MATERIALS AND METHODS

Twenty-eight patients with CF (15 male, 13 female, mean age 30.5±9.4 years) underwent CT and MRI of the lung. MRI (1.5 T) included different T2- and T1-weighted sequences: breath-hold HASTE (half Fourier acquisition single shot turbo spin echo) and VIBE (volumetric interpolated breath-hold examination, before and after contrast medium administration) sequences and respiratory-triggered PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences with and without fat signal suppression, and perfusion imaging. CT and MRI images were evaluated by the modified Helbich and the Eichinger scoring systems. The clinical follow-up analysis assessed pulmonary exacerbations within 24 months.

RESULTS

The highest concordance to CT was achieved for the PROPELLER sequences without fat signal suppression (concordance correlation coefficient CCC of the overall modified Helbich score 0.93 and of the overall Eichinger score 0.93). The other sequences had the following concordance: PROPELLER with fat signal suppression (CCCs 0.91 and 0.92), HASTE (CCCs 0.87 and 0.89), VIBE (CCCs 0.84 and 0.85) sequences. In the outcome analysis, the combined MRI analysis of all five sequences and a specific MRI protocol (PROPELLER without fast signal suppression, VIBE sequences, perfusion imaging) reached similar correlations to the number of pulmonary exacerbations as the CT examinations.

CONCLUSION

An optimum lung MRI protocol in patients with CF consists of PROPELLER sequences without fat signal suppression, VIBE sequences, and lung perfusion analysis to enable high diagnostic efficacy and outcome prediction.

Impact of ultrasound examination shortly after kidney transplantation

Background

Ultrasound is routinely performed at our transplant unit within the first 48 h of kidney transplantation (KTX). The objective of this study was to evaluate the association of ultrasound results and, in particular, elevated resistance indices (RIs) with the occurrence of surgical complications and allograft outcomes.

Methods

The study included all kidney allograft recipients undergoing transplantation at our center between January 2010 and December 2011 (N = 329). Ultrasound examination was performed on 315 recipients (95.7%).

Results

Delayed graft function was more common in subjects with a high RI (≥0.7) than in patients with an RI < 0.7 (47.2 vs. 28.2%; p = 0.032). A lack of arterial signal was detected in eight patients (2.5%), of whom five had a vascular complication that required surgical therapy. In 12 patients (3.8%), RI was 1 without any other signs of vascular impairment. Even though such values can be a sign of venous thrombosis, no case was observed in any of these patients.

Conclusions

The results of our study suggest that ultrasound evaluation of the transplanted kidney shortly after transplantation is a valuable tool not only for detecting vascular complications but also as a predictor of graft outcome regarding delayed graft function.

"Bowel prep hyponatremia" - a state of acute water intoxication facilitated by low dietary solute intake: case report and literature review

Background

Symptomatic hyponatremia is considered a rare complication of oral bowel preparation for colonoscopy. The pathophysiology underlying this phenomenon has been widely regarded as a mere sequela of excessive arginine vasopressin (AVP) release.

Case presentation

This case describes a 61-year old woman who developed acute hyponatremic encephalopathy when preparing for elective outpatient lower endoscopy. She had had negligible oral solute intake for two days and ingested four liters of clear fluid within two hours. On admission, the patient was agitated and had slurred speech. Treatment with hypertonic saline lead to full recovery. A brisk aquaresis confirmed acute dilutional hyponatremia.

Conclusion

Apart from elevated AVP-levels, the amount and speed of fluid intake and concomitant low-solute intake constitute important risk factors in the development of clinically relevant hyponatremias in patients undergoing colonoscopies. Understanding that the cause of sodium imbalance in this scenario is multifactorial and complex is pivotal to recognizing and ideally preventing this complication, for which we propose the term “bowel prep hyponatremia”.

The Immunosuppressive Effect of CTLA4 Immunoglobulin Is Dependent on Regulatory T Cells at Low But Not High Doses

B7.1/2-targeted costimulation blockade (CTLA4 immunoglobulin [CTLA4-Ig]) is available for immunosuppression after kidney transplantation, but its potentially detrimental impact on regulatory T cells (Tregs) is of concern. We investigated the effects of CTLA4-Ig monotherapy in a fully mismatched heart transplant model (BALB/c onto C57BL/6). CTLA4-Ig was injected chronically (on days 0, 4, 14, and 28 and every 4 weeks thereafter) in dosing regimens paralleling clinical use, shown per mouse: low dose (LD), 0.25 mg (≈10 mg/kg body weight); high dose (HD), 1.25 mg (≈50 mg/kg body weight); and very high dose (VHD), 6.25 mg (≈250 mg/kg body weight). Chronic CTLA4-Ig therapy showed dose-dependent efficacy, with the LD regimen prolonging graft survival and with the HD and VHD regimens leading to >95% long-term graft survival and preserved histology. CTLA4-Ig's effect was immunosuppressive rather than tolerogenic because treatment cessation after ≈3 mo led to rejection. FoxP3-positive Tregs were reduced in naïve mice to a similar degree, independent of the CTLA4-Ig dose, but recovered to normal values in heart recipients under chronic CTLA4-Ig therapy. Treg depletion (anti-CD25) resulted in an impaired outcome under LD therapy but had no detectable effect under HD therapy. Consequently, the immunosuppressive effect of partially effective LD CTLA4-Ig therapy is impaired when Tregs are removed, whereas CTLA4-Ig monotherapy at higher doses effectively maintains graft survival independent of Tregs.

Impact of Neoadjuvant Chemotherapy on Clinical Risk Scores and Survival in Patients with Colorectal Liver Metastases

BACKGROUND

Several clinical risk scores for patients with colorectal liver metastases (CLM) were established in cohorts of patients undergoing liver resection (LR) without neoadjuvant chemotherapy (NAC). The purpose of the study was to evaluate the predictive values of four common risk scores in the setting of NAC and the impact of score changes during NAC.

METHODS

Risk scores (Fong, Nordlinger, Nagashima, and Konopke) were retrospectively calculated for 336 patients undergoing LR for CLM, including 109 patients without and 227 patients with NAC. In patients with NAC, the scores were calculated before and after NAC.

RESULTS

In patients without NAC (n = 109), all risk scores except the Konopke score showed a significant correlation with disease-free survival (DFS). Only the Nagashima score also was predictive for overall survival (OS). In patients with NAC (n = 227), all scores except the Konopke score were predictive for DFS and OS before and after NAC. Score changes in the Fong and the Nagashima score showed a significant correlation with DFS and OS.

CONCLUSIONS

Nagashima score was the most universally applicable score and predicted prognosis in all tested scenarios.

Incomplete clonal deletion as prerequisite for tissue-specific minor antigen tolerization

Central clonal deletion has been considered the critical factor responsible for the robust state of tolerance achieved by chimerism-based experimental protocols, but split-tolerance models and the clinical experience are calling this assumption into question. Although clone-size reduction through deletion has been shown to be universally required for achieving allotolerance, it remains undetermined whether it is sufficient by itself. Therapeutic Treg treatment induces chimerism and tolerance in a stringent murine BM transplantation model devoid of myelosuppressive recipient treatment. In contrast to irradiation chimeras, chronic rejection (CR) of skin and heart allografts in Treg chimeras was permanently prevented, even in the absence of complete clonal deletion of donor MHC-reactive T cells. We show that minor histocompatibility antigen mismatches account for CR in irradiation chimeras without global T cell depletion. Furthermore, we show that Treg therapy-induced tolerance prevents CR in a linked suppression-like fashion, which is maintained by active regulatory mechanisms involving recruitment of thymus-derived Tregs to the graft. These data suggest that highly efficient intrathymic and peripheral deletion of donor-reactive T cells for specificities expressed on hematopoietic cells preclude the expansion of donor-specific Tregs and, hence, do not allow for spreading of tolerance to minor specificities that are not expressed by donor BM.

IL-2/α-IL-2 Complex Treatment Cannot Be Substituted for the Adoptive Transfer of Regulatory T cells to Promote Bone Marrow Engraftment

Cell therapy with recipient Tregs achieves engraftment of allogeneic bone marrow (BM) without the need for cytoreductive conditioning (i.e., without irradiation or cytotoxic drugs). Thereby mixed chimerism and transplantation tolerance are established in recipients conditioned solely with costimulation blockade and rapamycin. However, clinical translation would be substantially facilitated if Treg-stimulating pharmaceutical agents could be used instead of individualized cell therapy. Recently, it was shown that interleukin-2 (IL-2) complexed with a monoclonal antibody (mAb) (clone JES6-1A12) against IL-2 (IL-2 complexes) potently expands and activates Tregs in vivo. Therefore, we investigated whether IL-2 complexes can replace Treg therapy in a costimulation blockade-based and irradiation-free BM transplantation (BMT) model. Unexpectedly, the administration of IL-2 complexes at the time of BMT (instead of Tregs) failed to induce BM engraftment in non-irradiated recipients (0/6 with IL-2 complexes vs. 3/4 with Tregs, p<0.05). Adding IL-2 complexes to an otherwise effective regimen involving recipient irradiation (1Gy) but no Treg transfer indeed actively triggered donor BM rejection at higher doses (0/8 with IL-2 complexes vs. 9/11 without, p<0.01) and had no detectable effect at two lower doses (3/5 vs. 9/11, p>0.05). CD8 T cells and NK cells of IL-2 complex-treated naïve mice showed an enhanced proliferative response towards donor antigens in vitro despite the marked expansion of Tregs. However, IL-2 complexes also expanded conventional CD4 T cells, CD8 T cells, NK cells, NKT cells and notably even B cells, albeit to a lesser extent. Notably, IL-2 complex expanded Tregs featured less potent suppressive functions than in vitro activated Tregs in terms of T cell suppression in vitro and BM engraftment in vivo. In conclusion, these data suggest that IL-2 complexes are less effective than recipient Tregs in promoting BM engraftment and in contrast actually trigger BM rejection, as their effect is not sufficiently restricted to Tregs but rather extends to several other lymphocyte populations.

A comparison of Frailty Indexes Based on a Comprehensive Geriatric Assessment for the Prediction of Adverse Outcomes

OBJECTIVE

To compare the ability of different frailty indexes based on a standardized comprehensive geriatric assessment (FI-CGAs) for predicting adverse outcomes.

DESIGN AND SETTING

Prospective cohort study. Geriatric wards of a general hospital.

PARTICIPANTS

307 hospitalized patients ≥ 65 years.

MEASUREMENTS

The FI-CGA-10D (potential health deficits in ten functional domains), the FI-CGA-10D+CM (aforementioned potential health deficits and co-morbidity burden) and the FI-CGA-MIHD (multiple, individual potential health deficits, including functional deficits, co-morbid diseases, amongst others) were assessed at baseline during the patients` hospital stay. The FI-CGAs were analyzed as categorical (according to a FI-CGA score < and ≥ 0.25) and continuous variables. Patients were followed up over 6 months.

RESULTS

The FI-CGA-10D, FI-CGA-10+CM and the FI-CGA-MIHD predicted 6-month mortality when expressed as categorical (area under the receiver operating characteristic curve (AUC): AUC = 0.611, AUC = 0.637, AUC = 0.616, all p < 0.050, respectively) or continuous variables (AUC = 0.769, AUC = 0.837, AUC = 0.834, all p < 0.001, respectively). AUC comparisons showed that all three FI-CGAs exhibited a comparable ability to predict 6-month mortality when the FI-CGAs were expressed as categorical variables (all p > 0.200) and the FI-CGA-10D+CM and the FI-CGA-MIHD showed a better ability to predict 6-month mortality than the FI-CGA-10D, when the FI-CGAs were expressed as continuous variables (p < 0.001 and p = 0.007, respectively). None of the FI-CGAs predicted any of the other outcomes, i.e., unplanned re-admission to hospital and a fall during follow-up, irrespective of whether the FI-CGAs were expressed as categorical or continuous variables (all p ≥ 0.050).

CONCLUSIONS

The more complex FI-CGAs, i.e., the FI-CGA-10D+CM and the FI-CGA-MIHD, revealed better ability to predict 6 month mortality than the more simple FI-CGA, i.e., the FI-CGA-10D.

Analysis of Rockwood et Al's Clinical Frailty Scale and Fried et Al's Frailty Phenotype as Predictors of Mortality and Other Clinical Outcomes in Older Patients Who Were Admitted to a Geriatric Ward

OBJECTIVES

There are few data regarding the accuracy of short frailty tools as predictors of mortality and other clinical outcomes of older patients admitted to a geriatric ward. We therefore analyzed the accuracy of Rockwood et al's Clinical Frailty Scale and an easy and quick to perform operationalization of Fried et al's frailty phenotype, as predictors of mortality and other clinical outcomes in our cohort of patients.

DESIGN

Prospective analysis with a follow-up period of 6 months.

SETTING AND PARTICIPANTS

307 patients who were 65 years of age or older were included in the study. The patients were assessed in terms of the two frailty measures during their stay in a geriatric ward.

RESULTS

The Clinical Frailty Scale and the frailty phenotype were both suitable for differentiating between patients who died due to any cause from those who survived during follow-up (primary outcome) (area under the ROC curves (AUC) values 0.867 (95% CI 0.807-0.926), p<0.001 and 0.754 (95% CI 0.688-0.821), p<0.001, respectively). Regarding the secondary outcomes: 1. unplanned admission to hospital and 2. a fall during follow-up, the Clinical Frailty Scale discriminated or tended to discriminate between patients to whom these criteria applied and those to whom they did not (AUC=0.569 (95% CI 0.502-0.636), p=0.046 and AUC=0.574 (95% CI 0.501-0.647), p=0.071, respectively). The frailty phenotype did not show such a differentiation when applied to secondary outcomes (AUC=0.500 (95% CI 0.432-0.568), p=0.994 and AUC=0.518 (95% CI 0.439-0.598), p=0.658, respectively).

CONCLUSIONS

Both short frailty instruments are suitable predictors of mortality in older patients who were admitted to a geriatric ward. The Clinical Frailty Scale, but not the frailty phenotype, predicted at least some of the secondary outcomes, i.e., the outcome unplanned admission to hospital during follow-up.

[Cystic fibrosis and associated complications]

Cystic fibrosis (CF) is an autosomal recessive inherited metabolic disease. The mutation is located on the long arm of chromosome 7. Due to a defect in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, chloride ion transport is reduced across the cell membrane. As a result, the disease can be described as an exocrinopathy. In all organs with exocrine glands, disorders occur in association with the defective chloride transport. The main impact of this defect is manifested in the lungs. Therefore, the most common cause of death is pulmonary disease with respiratory insufficiency due to recurrent infections. Unfortunately, a cure for the disease is still not available. However, new therapies that may affect the CFTR mutation more specifically give new hope for better therapeutic options in the future. The long-term goal of therapy is to develop a causal therapy for all six different mutation classes and thus for about 2000 mutations.

Abdominal drainage after liver transplantation from deceased donors

PURPOSE

Traditionally, abdominal drainage (AD) is routinely inserted in patients after liver transplantation (LT) to drain ascites and to detect postoperative hemorrhage and bile leakage. However, the benefit of this surgical practice remains a matter of debate regarding potential drainage-associated morbidities.

METHODS

In a retrospective pair-matched analysis in a 1:1 ratio, 116 patients after LT were assessed with regards to benefits and risks of abdominal drainage under immunosuppression, respecting model for end-stage liver disease (MELD), age, and gender.

RESULTS

The indications for LT were comparable between the drain and the no-drain group. There was an increased rate of early bile leakage in patients with abdominal drainage (13.8 vs. 1.7%, p = 0.032). In addition, a significantly higher incidence of infections requiring antibiotic therapy was observed in the drain group (63.8 vs. 39.7%, p = 0.015). The contribution of drains as a diagnostic tool was marginal, as in the drain group, other diagnostic tools than the drain itself confirmed 50% of all early bile leakages and 60% of postoperative hemorrhages. Overall, there was no difference regarding the incidence of incisional hernia after LT (8.6 vs. 10.3%, p = 1.000), length of hospital stay (22.9 ± 18.7 vs. 18.6 ± 18.6 days, p = 0.215), and 1- and 5-year patient (p = 0.981) and graft survival (p = 0.092).

CONCLUSIONS

Equal results can be achieved with or without an abdominal drain in recipients with whole-liver grafts in spite of an increased risk of postoperative infection and biliary leakage in the former group. A benefit of AD as a diagnostic tool could not be demonstrated.