Peritoneal Dialysis Technique Survival: A Cohort Study

RATIONALE & OBJECTIVE

Reasons for transfer from peritoneal dialysis (PD) to hemodialysis (HD) remain incompletely understood. Among incident and prevalent patients receiving PD, we evaluated the association between prior treatment with HD and PD technique survival.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults who initiated PD at a Dialysis Clinic, Inc. (DCI) outpatient facility between January 1, 2010 and September 30, 2019.

EXPOSURES

The primary exposure of interest was timing of PD start, categorized as PD-first, PD-early, or PD-late. Other covariates included demographics, clinical characteristics, and routine laboratory results.

OUTCOMES

Modality switch from PD to HD sustained for more than 90 days.

ANALYTICAL APPROACH

Multivariable Fine-Gray models with competing risks and time-varying covariates, stratified at 9 months to account for lack of proportionality.

RESULTS

Among 5224 patients who initiated PD at a DCI facility, 3174 initiated dialysis with PD ("PD-first"), 942 transitioned from HD to PD within 90 days ("PD-early"), and 1108 transitioned beyond 90 days ("PD-late"); 1472 (28%) subsequently transferred from PD to HD. PD-early and PD-late patients had higher risk of transfer to HD as compared to PD-first patients [adjusted hazard ratio (aHR) 1.51 (95% CI: 1.17-1.96) and 2.41 (1.94-3.00), respectively, in the first 9 months and aHR 1.16 (0.99-1.35) and 1.43 (1.24-1.65), respectively, after 9 months]. More peritonitis episodes, fewer home visits, lower serum albumin, lower residual kidney function, and lower peritoneal clearance calculated with weekly Kt/V were additional risk factors for PD-to-HD transfer.

LIMITATIONS

Missing data on dialysis adequacy and residual kidney function, confounded by short PD technique survival.

CONCLUSIONS

Initiating dialysis with PD is associated with greater PD technique survival, though many of those who initiate PD late in their dialysis course still experience substantial time on PD. Peritonitis, lower serum albumin, and lower Kt/V are risk factors for PD-to-HD transfer that may be amenable to intervention.

Current approach to hepatobiliary manifestations in inflammatory bowel disease

Inflammatory bowel disease (IBD), including the two main subtypes - Crohn's disease (CD) and ulcerative colitis (UC) - has a wide range of extra-intestinal manifestations (EIMs) that are major causes of morbidity and disability. The following EIMs can be classified as IBD-associated: mucocutaneous, ocular, pulmonary, renal, genitourinary, hematological, neurological, psychiatric, cardiac and hepatobiliary. The latter include primary sclerosing cholangitis (PSC), cholelithiasis, IgG4 associated cholangiopathy (IAC), autoimmune hepatitis (AIH), non-alcoholic fatty liver disease (NAFLD), hepatitis B and C, and drug-induced hepatotoxicity. The aim of this review is to examine our current knowledge of IBD - associated hepatobiliary EIMs and their treatment.

Significance of Screening Tests and the Incidence of New Delhi Metallo-beta-lactamase-Producing Gram-negative Bacilli in the Surgery and Transplantation Wards of a Warsaw Medical Center During the Period From April 2014 to May 2017

BACKGROUND

The first New Delhi metallo-beta-lactamase (NDM)-producing bacteria were isolated in 2008 in the world, and in 2011 in Poland. Due to the high clonal diversity (17 types) of their blaNDM gene, encoded on (Tn125-like) mobile genetic elements, these strains usually exhibit resistance to nearly all available antibiotics, which is particularly dangerous for organ transplant recipients.

PURPOSE

To assess of the prevalence of Gram-negative NDM-positive bacilli in surgery/transplantation wards of a teaching hospital in Warsaw and to ascertain the significance of screening tests on the rates and nature of colonization.

MATERIALS AND METHODS

The evaluated strains were isolated from 30 patients (between April 2014 and May 2017). The species were identified with VITEK-MS, antibiotic susceptibility was determined with VITEK 2, disk-diffusion, and/or E-test methods, according to EUCAST guidelines. The presence of the blaNDM-1 gene was confirmed using the polymerase chain reaction technique.

RESULTS AND CONCLUSIONS

There were 77 blaNDM-1-positive Klebsiella pneumoniae strains isolated from 30 patients. Cultures from individual patients, mainly from rectal swabs (53.9%) and urine samples (39.8%), yielded 1-11 isolates. Fifteen patients were already colonized on admission, and the other 15 developed a symptomatic infection. In total, 24 (80%) patients were carriers, and their colonizations persisted for <1-20 months. Most isolates were susceptible only to colistin, gentamicin, amikacin, tigecycline, and/or sulfamethoxazole/trimethoprim. Gastrointestinal-tract-colonizing K pneumoniae are the main reservoir of the blaNDM-1 gene. Following the introduction of on-admission mandatory screening for carbapenem-resistant strains, the rates of NDM-producing K pneumoniae isolation increased (7.5-fold), while the rates of isolation from patients with symptomatic infections considerably decreased (2.8-fold).

Effect of Selective Antibiotic Pressure on the MLS-B Phenotype in Methicillin-Resistant Staphylococcus aureus Strains Originating From Patients From Transplantation Wards: 24 Years of Observations

INTRODUCTION

Staphylococcus aureus infection, and health care-associated-methicillin resistant S aureus (HA-MRSA) in particular, is a serious risk for patients treated with organ transplantation. The frequent combined resistance of these bacteria to macrolides, lincosamides, and streptogramin-B (MLS-B) limits the use of these drugs in therapy.

AIM

Evaluation of the mechanism of MLS-B resistance among HA-MRSA strains derived from patients treated in surgical-transplantation wards, over a 24-year period, and assessment of correlation of clindamycin use and resistance phenotype.

MATERIALS AND METHODS

One hundred and twelve HA-MRSA strains from patients in surgical-transplantation wards (clinical hospital, Warsaw), hospitalized in the period from 1991 to 2014. Methicillin-resistance was determined using phenotypic and genetic methods by detecting the mecA gene. Erythromycin/clindamycin resistance was determined by E-test, the iMLS-B (inductive) and cMLS-B (constitutive) phenotypes by the D-test method. The number of defined daily doses (DDD), statistically per 1000 person-days, was calculated in accordance with the WHO guidelines.

RESULTS

Resistance to erythromycin/clindamycin in MRSA strains increased from 1991 to 2004-2007 from 64.7/11.8% to 100/76.9%, respectively. The frequency of the cMLS-B phenotype in the years 1991/2010-2011/2012 was 5.9%/76.9%/69.7%, respectively, and correlated with the increased use of clindamycin in the examined wards. In 2012, the percentage of MLS-B-sensitive isolates increased from 3.9 to 21.7%, while constitutive resistance decreased to 69.7%, which correlated with a decrease in the use of clindamycin.

CONCLUSIONS

The proportion of cMLS-B to iMLS-B phenotypes in HA-MRSA is related to the amount of clindamycin used in hospital wards. Limiting the selection pressure of antibiotics can lead to complete loss of resistance or return to the inductive mechanism of its regulation.

Comparison of Staphylococcal Flora in Denture Plaque and the Surface of the Pharyngeal Mucous Membrane in Kidney Transplant Recipients

BACKGROUND

Biofilm occurring on removable prostheses is a reservoir of bacterial flora, consisting of both physiological and pathogenic multidrug-resistant microorganisms. Patients undergoing dialysis and organ transplantation are particularly prone to bacterial infections, which can have its source in denture plaque. This study was a comparison of the composition of staphylococcal flora within the surface of the pharyngeal mucous membrane as well as denture plaque in kidney transplant recipients.

METHODS

The study included 44 subjects with removable prostheses who reported for a kidney transplant procedure. Swab samples were collected from prostheses and the pharyngeal wall. Isolated strains were identified and investigated for drug resistance.

RESULTS

A total of 72 strains of Staphylococcus were isolated from the denture plaque and 53 from the pharynx. In the pharynx, the following species prevailed: Staphylococcus epidermidis, Staphylococcus warneri, and Staphylococcus aureus. The following species prevailed in denture plaque: S epidermidis, S aureus, and Staphylococcus haemolyticus. Among the pharyngeal strains, antibiotic resistance most commonly referred to natural penicillin (77%), constitutive macrolide-lincosamide-streptogramin B resistance (28%), and tetracycline (26.4%). In case of denture plaque, the highest percentage of strains demonstrated resistance to natural penicillin (60%), fosfomycin (32%), and cefoxitin (25%). In 10 subjects (48%), Staphylococcus-induced infections occurred in the first year after transplantation, 5 of which had the same bacterial strain as cultured previously from dentures.

CONCLUSIONS

The denture biofilm and surface of the pharynx differ in terms of bacterial composition and bacterial drug resistance profiles. Denture plaque constitutes a considerable reservoir of staphylococcal flora, which can be a potential source of infection in organ transplant recipients.

Tumour-associated macrophages influence canine mammary cancer stem-like cells enhancing their pro-angiogenic properties

Cancer stem-like cells as cells with ability to self-renewal and potential to differentiate into various types of cells are known to be responsible for tumour initiation, recurrence and drug resistance. Hence a comprehensive research is concentrated on discovering cancer stem-like cells biology and interdependence between them and other cells. The aim of our study was to evaluate the impact of macrophages on cancer stem-like cells in canine mammary carcinomas. As recent studies indicated presence of macrophages in cancer environment stimulates cancer cells into more motile and invasive cells by acquisition of macrophage phenotypes. From two canine mammary tumour cell lines, CMT-U27 and P114 cancer stem-like cells were stained with Sca1, CD44 and EpCAM monoclonal antibodies and isolated. Those cells were next co-cultured with macrophages for 5 days and used for further experiments. Canine Gene Expression Microarray revealed 29 different expressed transcripts in cancer stem-like cells co-cultured with macrophages compared to those in mono-culture. Up-regulation of C-C motif chemokine 2 was considered as the most interesting for further investigation. Additionally, those cells showed overexpression of genes involved in non-canonical Wnt pathway. The results of 3D tubule formation in endothelial cells induced by cancer stem-like cells co-cultured with macrophages compared to cancer stem-like cells from mono-cultures and with addition of Recombinant Canine CCL2/MCP-1 revealed the same stimulating effect. Based on those results we can conclude that macrophages have an impact on cancer stem-like cells increasing secretion of pro-angiogenic factors.

Ergocalciferol Supplementation in Hemodialysis Patients With Vitamin D Deficiency: A Randomized Clinical Trial

Locally produced 1,25-dihydroxyvitamin D3 may have pleiotropic effects outside of bone. Experimental and observational studies suggest that nutritional vitamin D may enhance erythropoiesis in settings of 25-hydroxy vitamin D (25(OH)D) deficiency. We conducted a double-blind, placebo-controlled, randomized clinical trial to assess the effects of supplementation with ergocalciferol on epoetin utilization and other secondary outcomes in patients on hemodialysis with serum 25(OH)D <30 ng/ml. In all, 276 patients were randomized to 6 months of ergocalciferol or placebo. Mean±SD serum 25(OH)D increased from 16.0±5.9 ng/ml at baseline to 39.2±14.9 ng/ml in the ergocalciferol arm and did not change (16.9±6.4 ng/ml and 17.5±7.4 ng/ml, respectively) in the placebo arm. There was no significant change in epoetin dose over 6 months in the ergocalciferol or placebo arms (geometric mean rate 0.98 [95% confidence interval (95% CI), 0.94 to 1.02] versus 0.99 [95% CI, 0.95 to 1.03], respectively) and no difference across arms (P=0.78). No change occurred in serum calcium, phosphorus, intact parathyroid hormone, or C-reactive protein levels, cinacalcet use, or phosphate binder or calcitriol dose in either study arm. Rates of all-cause, cardiovascular, and infection-related hospitalizations did not differ by study arm, although statistical power was limited for these outcomes. In conclusion, 6 months of supplementation with ergocalciferol increased serum 25(OH)D levels in patients on hemodialysis with vitamin D insufficiency or deficiency, but had no effect on epoetin utilization or secondary biochemical and clinical outcomes.

Analysis of microRNA expression in canine mammary cancer stem-like cells indicates epigenetic regulation of transforming growth factor-beta signaling

Cancer stem cells (CSCs) display both unique self-renewal ability as well as the ability to differentiate into many kinds of cancer cells. They are supposed to be responsible for cancer initiation, recurrence and drug resistance. Despite the fact that a variety of methods are currently employed in order to target CSCs, little is known about the regulation of their phenotype and biology by miRNAs. The aim of our study was to assess miRNA expression in canine mammary cancer stem-like cells (expressing stem cell antigen 1, Sca-1; CD44 and EpCAM) sorted from canine mammary tumour cell lines (CMT-U27, CMT-309 and P114). In order to prove their stem-like phenotype, we conducted a colony formation assay that confirmed their ability to form colonies from a single cell. Profiles of miRNA expression were investigated using Agilent custom-designed microarrays. The results were further validated by real-time rt-PCR analysis of expression of randomly selected miRNAs. Target genes were indicated and analysed using Kioto Encyclopedia of Genes and Genomes (KEGG) and BioCarta databases. The results revealed 24 down-regulated and nine up-regulated miRNAs in cancer stem-like cells compared to differentiated tumour cells. According to KEGG and BioCarta databases, target genes (n=240) of significantly down-regulated miRNAs were involved in transforming growth factor-beta signaling, mitogen-activated protein kinases (MAPK) signaling pathway, anaplastic lymphoma receptor tyrosine kinase (ALK) and peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC1A) pathways. The analysis of single-gene overlapping with different pathways showed that the most important genes were: TGFBR1, TGFBR2, SOS1, CHUK, PDGFRA, SMAD2, MEF2A, MEF2C and MEF2D. All of them are involved in tumor necrosis factor-beta signaling and may indicate its important role in cancer stem cell biology. Increased expression of TGFBR2, SMAD2, MEF2A and MEF2D in canine mammary cancer stem-like cells was further confirmed by real-time-qPCR. The results of our study point at epigenetic differences between cancer stem-like cells and differentiated tumour cells, which may be important not only for veterinary medicine but also for comparative oncology.

Expression of inflammation-mediated cluster of genes as a new marker of canine mammary malignancy

Because canine mammary tumours constitute a serious clinical problem and there are no good prognostic markers (only histopathological variables are used), the aim of the presented study was to find new malignancy markers as well as to identify intracellular pathways and biological processes characteristic for canine mammary malignancy. We compared gene expression of the most malignant mammary tumours (poorly differentiated cancers of the 3rd grade of malignancy) with less malignant tumours (well differentiated cancers of the 1st grade of malignancy). The results of our study indicated that in dogs the number of tumour-infiltrating myeloid cells or expression of myeloid-specific antigens by cancer cells is related to the cancer progression and may constitute a new marker of malignancy, however further studies in this field are required.

Why chemotherapy can fail?

There are many reasons that lead to failure of cancer chemotherapy. Cancer has the ability to become resistant to many different types of drugs. Increased efflux of drug, enhanced repair/increased tolerance to DNA damage, high antiapoptotic potential, decreased permeability and enzymatic deactivation allow cancer cell survive the chemotherapy. Treatment can lead to the death of most tumor cells (drug-sensitive), but some of them (drug-resistant) survive and grow again. These tumor cells may arise from stem cells. There are many studies describing human experiments with multidrug resistance, especially in breast cancer. Unfortunately, studies of canine or feline ABC super family members are not as extensive as in human or mice and they are limited to several papers describing PGP in mammary cancer, cutaneous mast cell tumors and lymphoma. Multidrug resistance is one of the most significant problems in oncology today. The involvement of many different, not fully recognized, mechanisms in multidrug resistance of cancer cells makes the development of effective methods of therapy very difficult. Understanding the mechanisms of drug resistance in cancer cells may improve the results of treatment. This review article provides a synopsis of all aspects that refer to cancer cell resistance to antitumor drugs.

Surgical treatment of the tentorial and falco-tentorial junction meningiomas

INTRODUCTION

Tentorial meningiomas account for 3-7.7% of all meningiomas in surgically treated patients. In this group, the falco-tentorial meningiomas are considered to be the rarest.

CASE REPORT

The paper presents three cases of the tentorial and falco-tentorial junction meningiomas. Two of the meningiomas were of major size and with an attachment at the falco-tentorial junction, while the other was attached to the inferior notch of the tentorium. The lesions manifested as headaches and disequilibrium that persisted for many years. The Parinaud syndrome and diplopia were observed in the patient with the meningioma attachment at the inferior notch of the tentorium. One of the lesions was resected completely using an occipital bitranstentorial/falcine approach. In the second case an occipito-transtentorial approach was used. However, during the surgery problems arose with resecting the lesion on the other side. The meningioma of the inferior notch of the tentorium was vascularized through the tentorial artery stemming from the meningo-hypophyseal trunk of the intracavitary section of the internal carotid artery on the right side. This meningioma required a two-stage operation. The surgical treatment was satisfactory and depended on the patient's condition at the time of the surgery.

CONCLUSION

The presented rare cases of tentorial and falco-tentorial junction meningiomas seem to suggest that their treatment should be surgical and launched promptly after making a diagnosis. The results of the treatment might then be favourable.

Predicting energy expenditure of physical activity using hip- and wrist-worn accelerometers

To investigate the association between physical activity and health, we need accurate and detailed free-living physical activity measurements. The determination of energy expenditure of activity (EEACT) may also be useful in the treatment and maintenance of nutritional diseases such as diabetes mellitus. Minute-to-minute energy expenditure during a 24-h period was measured in 60 sedentary normal female volunteers (35.4 +/- 9.0 years, body mass index 30.0 +/- 5.9 kg/m2), using a state-of-the-art whole-room indirect calorimeter. The activities ranged from sedentary deskwork to walking and stepping at different intensities. Body movements were simultaneously measured using a hip-worn triaxial accelerometer (Tritrac-R3D, Hemokentics, Inc., Madison, Wisconsin) and a wrist-worn uniaxial accelerometer (ActiWatch AW64, MiniMitter Co., Sunriver, Oregon) on the dominant arm. Movement data from the accelerometers were used to develop nonlinear prediction models (separately and combined) to estimate EEACT and compared for accuracy. In a subgroup (n=12), a second 24-h study period was repeated for cross-validation of the combined model. The combined model, using Tritrac-R3D and ActiWatch, accurately estimated total EEACT (97.7 +/- 3.2% of the measured values, p=0.781), as compared with using ActiWatch (86.0 +/- 4.7%, p<0.001) or Tritrac-R3D (90.0 +/- 4.6%, p<0.001) alone. This model was also accurate for all intensity categories during various physical activities. The subgroup cross-validation also showed accurate and reproducible predictions by the combination model. In this study, we demonstrated that movement measured using accelerometers at the hip and wrist could be used to accurately predict EEACT of various types and intensity of activities. This concept can be extended to develop valid models for the accurate measurement of free-living energy metabolism in clinical populations.

[Surgical treatment of pineal and tectal tumors from the subtentorial and supracerebellar approach]

The results of operative treatment of pineal and tectal tumours by infratentorial, supracerebellar approach were presented. There were 15 patients with pineal and 2 with tectal tumours. Clinical symptoms of the disease were as follows: signs of intracranial hypertension, tectal lesion, impairment of gait and hypoacusis. Diagnostic procedure included CT, MRI, and panangiography investigation. Application of infratentorial, supracerebellar approach enabled total resection of tumours in 14 patients (82.3%) and subtotal in 2 patients (11.8%) In 1 patient we managed to do only diagnostic biopsy (5.9%). This approach makes possible removal of pineal and tectal tumours growing in the midline toward the anterior part of III ventricle and also posterior fossa. The advantage of this approach is fact that the operation takes place below the vein of Galen. Drooping by gravity cerebellum creates enough places for microsurgical operation. During control investigation 13 patients (76%) had no announce any complaints and were without neurological disorders.

[Therapeutic management of massive hemorrhage caused by gastroduodenal ulcer]

Based on 103 patients the authors discussed policy of therapeutic management in gastric and duodenal ulcer disease complicated by massive hemorrhage. In the surgical treatment of such patients the authors prefer resection procedures aimed at simultaneous control of bleeding, prevention of its relapse and radical treatment of peptic ulcer disease.

[Experimental gluing of the pleural cavity]

In experimental research on rabbits the authors assessed the usefulness of tissue adhesive-GRF in obtaining tissue union in the pleural cavity to replace aspiration drainage after thoracosurgical operations. The experiments were carried out on rabbits under general anaesthesia in two groups. First group had thoracotomy and after expansion of the lungs the chest was closed tightly. In second group after thoracotomy the lungs were stabilized with gelatin-resorcin-formaldehyde glue. Aspiration drainage was not used. The observation included: radiologic examination, measurements of pulmonary ventilation using Wright's volumometer and gasometric determination. Moreover the alveolar-capillary oxygen difference and the percent of lung shunt were determined. The authors underline good function glued lungs.