Acute kidney injury following orthotopic liver transplantation: incidence, risk factors, and effects on patient and graft outcomes

BACKGROUND

Liver transplant recipients frequently develop acute kidney injury (AKI), but the predisposing factors and long-term consequences of AKI are not well understood. The aims of this study were to identify predisposing factors for early post-transplant AKI and the impact of AKI on patient and graft survival and to construct a model to predict AKI using clinical variables.

METHODS

In this 5-year retrospective study, we analysed clinical and laboratory data from 424 liver transplant recipients from our centre.

RESULTS

By 72 h post-transplant, 221 patients (52%) had developed AKI [according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria]. Predisposing factors for development of AKI were female sex, weight (>100 kg), severity of liver disease (Child-Pugh score), pre-existing diabetes mellitus, number of units of blood or fresh frozen plasma transfused during surgery, and non-alcoholic steatohepatitis as the aetiology of end-stage liver disease (P≤0.05). Notably, preoperative serum creatinine (SCr) was not a significant predisposing factor. After fitting a forward stepwise regression model, female sex, weight >100 kg, high Child-Pugh score, and diabetes remained significantly associated with the development of AKI within 72 h (P≤0.05). The area under the receiver operator characteristic curve for the final model was 0.71. The incidence of new chronic kidney disease and requirement for dialysis at 3 months and 1 yr post-transplant were significantly higher among patients who developed AKI.

CONCLUSIONS

Development of AKI within the first 72 h after transplant impacted short-term and long-term graft survival.

Acute hemodynamic changes after rapid intravenous bolus dosing of dexmedetomidine in pediatric heart transplant patients undergoing routine cardiac catheterization

BACKGROUND

Dexmedetomidine is a highly selective α(2)-adrenoceptor agonist with sedative, anxiolytic, and analgesic properties that has minimal effects on respiratory drive. Its sedative and hypotensive effects are mediated via central α(2A) and imidazoline type 1 receptors while activation of peripheral α(2B)-adrenoceptors result in an increase in arterial blood pressure and systemic vascular resistance. In this randomized, prospective, clinical study, we attempted to quantify the short-term hemodynamic effects resulting from a rapid i.v. bolus administration of dexmedetomidine in pediatric cardiac transplant patients.

METHODS

Twelve patients, aged 10 years or younger, weighing ≤40 kg, presenting for routine surveillance of right and left heart cardiac catheterization after cardiac transplantation were enrolled. After an inhaled or i.v. induction, the tracheas were intubated and anesthesia was maintained with 1 minimum alveolar concentration of isoflurane in room air, fentanyl (1 μg/kg), and rocuronium (1 mg/kg). At the completion of the planned cardiac catheterization, 100% oxygen was administered. After recording a set of baseline values that included heart rate (HR), systolic blood pressure, diastolic blood pressure, central venous pressure, systolic pulmonary artery pressure, diastolic pulmonary artery pressure, pulmonary artery wedge pressure, and thermodilution-based cardiac output, a rapid i.v. dexmedetomidine bolus of either 0.25 or 0.5 μg/kg was administered over 5 seconds. The hemodynamic measurements were repeated at 1 minute and 5 minutes.

RESULTS

There were 6 patients in each group. Investigation suggested that systolic blood pressure, diastolic blood pressure, systolic pulmonary artery pressure, diastolic pulmonary artery pressure, pulmonary artery wedge pressure, and systemic vascular resistance all increased at 1 minute after rapid i.v. bolus for both doses and decreased significantly to near baseline for both doses by 5 minutes. The transient increase in pressures was more pronounced in the systemic system than in the pulmonary system. In the systemic system, there was a larger percent increase in the diastolic pressures than the systolic pressures. Cardiac output, central venous pressure, and pulmonary vascular resistance did not change significantly. HR decreased at 1 minute for both doses and was, within the 0.5 μg/kg group, the only hemodynamic variable still changed from baseline at the 5-minute time point.

CONCLUSION

Rapid i.v. bolus administration of dexmedetomidine in this small sample of children having undergone heart transplants was clinically well tolerated, although it resulted in a transient but significant increase in systemic and pulmonary pressure and a decrease in HR. In the systemic system, there is a larger percent increase in the diastolic pressures than the systolic pressures and, furthermore, these transient increases in pressures were more pronounced in the systemic system than in the pulmonary system.

Radical prostatectomy in the treatment of prostate cancer. The experience of the Urology Clinic of Prof. Dr. Th. Burghele Clinical Hospital

INTRODUCTION

radical prostatectomy remains a real challenge for most of the urologists. Our study's objective is bringing into discussion the main aspects related to the technique we use, the intra and post-operatory complications, as well as the short-term analysis of the results in PC treatment using RP in the Prof. Dr. Th. Burghele Clinical Hospital - Clinic of Urology.

MATERIAL AND METHODS

between 1999 and 2007, 59 patients with PC, aged 48-74, were operated in our clinic. We began to recommend prostate biopsy (PB) to all patients with PSA higher than 4 ng/ml and, in the last years, higher than 2,5 ng/ml. A change in our attitude is related to the PB. At the beginning, we tried to perform "targeted" punctions, ultrasound guided especially in suspect zones, afterwards, we performed randomised punctions at all the patients, no matter the aspect of TRUS and we have increased the number of punctions accordingly to the prostate volume (minimum 6 punctions, maximum 12). The most used was the 10 core punction. The T classification, according to the clinical diagnosis, of the 59 operated patients: T1 cT1 a-b--4 cases; cT1 c--39 cases; T2 cT2 a--12 cases; cT2 b-c--4 cases. The RP surgical technique was the classic one, described by P.C. Walsh--the first surgical step, in all cases was lymphadenectomy.

RESULTS

of all the patients that went through RP, 56 cases are still in our records. We can consider healed 24 patients with PC, followed for 3 years post-surgery, because they had no need of therapy and the PSA is maintained below 0.02 ng/ml. The Gleason score--between the pre-operatory established diagnosis by punction and the anatomic-pathological examination of the piece, there were some differences: the concordance was in 48% of the cases; in 39% of the patients, the biopsy specimen had a lower Gleason score than the surgery specimen, and in 13% a higher score, the most common error was caused by sampling. The correlation between the pre-operatory evaluated clinical stage and the pathological clinical stage was of 57%. The most important late postoperative complications of RP were: urinary incontinence and erectile dysfunction. In our study, we have recorded late postoperative: complete urinary incontinence in 4 cases (6.7%), erection was maintained after bilateral preservation of neurovascular bandelets in 90% of cases and after unilateral preservation in 71% of cases. Due to the short following period, we can't say if the operated patients by us had a benefit regarding the general surviving period; The personalized interpretation of the increase of serum PSA levels after surgery represents a possible problem regarding the indication of complementary treatment.

Small cell carcinoma of the urinary bladder--a new case report

Primary pure small cell carcinoma of the urinary bladder is an extremely rare and highly aggressive tumor with an average five-year survival rate of less than 10% as cited by multiple case reports. It accounts for about 0.5-1% of all bladder tumors. We present the case of a 44-years-old man, smoker (10 cigarettes/day) hospitalized in the Department of Urology, from the "Prof. dr. Th. Burghele" Hospital, Bucharest, for one month intermittent hematuria. Ultrasonography showed a sessile tumoral mass, sized 37/30mm. Transurethral resection of the tumor mass was performed and tissue fragments were sent to the pathologic lab to establish the histologic type, the degree of differentiation and invasion. Fragments of the tumor were fixed in 10% formaldehyde, paraffin embedded and processed as standard technique; the sections were stained with HE, VG and immunohistochemically with: CROMO, EMA, NSE, CD56, NK1, p53 and betaHCG. The microscopic examination reveled a tumor proliferation composed of two distinct components: extensive small cells areas and foci of typical low grade (G2) papillary urothelial carcinoma. The small cell are uniformly, round, with increased nucleo-cytoplasmic ratio, eosinophyl cytoplasm, hyperchromatic nuclei, finely granular chromatin and inconspicuous nucleoli. Immunohistochemical stains showed diffuse positive staining of the small cell component for CROMO, EMA, NSE, CD56, NK1 and urothelial carcinoma component stained focally for betaHCG. The rate of cell proliferation was increased (p53 - 80% positive reaction). Conclusions. A diagnosis of small cell carcinoma coexisting with low-grade urothelial carcinoma was established. Because of aggressive behavior and distinct treatment, the pathologist should watch out for the presence of small cell carcinoma component.

Reproductive and offspring developmental effects following maternal inhalation exposure to methanol in nonhuman primates

INTRODUCTION

In an effort to improve air quality and decrease dependence on petroleum, the federal government, industry, and other groups have encouraged development of alternative fuels such as methanol to substitute for gasoline or diesel fuel. Methanol is also a candidate to provide the hydrogen for fuel cells, which are being developed for a variety of power sources (including motor vehicle engines). Before people are exposed to increased concentrations of methanol, the potential health effects of such exposures require study. Methanol, a simple alcohol containing one carbon atom, occurs naturally in plants and animals and participates in human metabolism. People regularly consume low doses of methanol in fruits, vegetables, and fermented beverages as well as soft drinks and foods sweetened with aspartame (which breaks down to methanol in the gastrointestinal tract). Despite its ubiquitous presence, methanol can be highly toxic if sufficient quantities are consumed. Ingestion of methanol (usually in the form of wood alcohol or tainted alcoholic beverages) can result in metabolic acidosis, blindness, and even death. Although the body has the capacity to metabolize the low doses of methanol to which people are regularly exposed, it cannot handle high doses because too much methanol overwhelms the body's ability to remove a toxic metabolite (formate). When formate accumulates, methanol poisoning occurs. One factor that regulates the rate at which formate is removed is the liver level of a derivative of the vitamin folic acid. People who are deficient in folic acid (including 15% to 30% of pregnant women) may be particularly susceptible to the toxic effects of methanol. If methanol were to be widely adopted as a fuel, environmental exposures would increase through ingestion of contaminated drinking water, inhalation of vapors from evaporative and other emissions, and dermal contact. Current concentrations of methanol in ambient air are very low, 1 to 30 parts per billion (ppb). If all motor vehicles in the United States were converted to 100% methanol fuel, methanol levels in ambient air are estimated to increase approximately 1,000-fold (to 1 to 10 ppm in cities) and in a worst-case situation could occasionally reach concentrations as high as 200 ppm in enclosed spaces (HEI 1987). Inhaling these concentrations of methanol for short periods of time is not predicted to affect formate production and thus should not present a health risk. However, little is known about the consequences of long-term inhalation of methanol vapors, especially in susceptible populations of pregnant women and developing fetuses. HEI, therefore, developed a research program to address this information gap.

APPROACH

Dr. Thomas Burbacher and colleagues of the University of Washington studied the effects of long-term exposure to methanol vapors on metabolism and reproduction in adult female monkeys (Macaca fascicularis) and developmental effects in their offspring, who were exposed prenatally to methanol. The investigators exposed adult female monkeys (11 to 12 animals/group) to one of four concentrations of methanol vapors (0, 200, 600, and 1,800 ppm) for 2.5 hours a day, seven days a week during the following periods: (1) before breeding, (2) during breeding, and (3) during pregnancy. They collected blood from the adults at regular intervals to monitor methanol levels (which served as a marker of internal dose) and formate concentrations. They also conducted pharmacokinetic studies to determine whether methanol disposition (which includes absorption, distribution, metabolism, and excretion) was altered as a result of repeated methanol exposures and to assess pregnancy-related changes. Because high doses of methanol damage the central nervous system, the infants (8 to 9 animals/group) were examined at regular intervals during the first nine months of life to assess their growth and neurobehavioral development.

RESULTS

Exposure to methanol vapors did n

Evaluation of apoptosis of tumor and of apparently normal cells in human renal carcinoma

Apoptosis of tumor cells and of apparently normal renal cells (ANRC) isolated from the same kidney in 42 untreated patients with renal carcinomas (RC) was evaluated. Thirty five of the investigated tumors were of Grawitz type in different grades of differentiation. The intensity of the apoptotic process was routinely assessed by propidium iodide staining and flow-cytometry analysis. Similar results were obtained in the same cases by using TUNEL assay, by staining with annexin V and by DNA electrophoresis. In 85% of Grawitz carcinomas the proportion of apoptotic tumor cells was quite high, with mean% +/- SD of 57.7+/-27.3, whereas in transitional cell carcinoma of the bladder (TCC), the mean percentage of cells in apoptosis was of 22.3+/-13.9. Unexpectedly, in ANRC displaying normal morphology and normal DNA content (diploidy), the mean% +/- SD of apoptotic cells were found to exceed that of apoptotic tumor cells, 79.2+/-21.6. The percentages of cells expressing Fas receptor and/or Fas ligand varied between large ranges in both tumor and ANRC, thus suggesting that other mechanisms are also involved in the activation of apoptosis. Immunohistochemical studies showed that the intensity of apoptosis correlated well with high p-53 and low bcl-2 expression. The intensity of apoptosis was generally not correlated with the cell proliferation index (S phase fraction), suggesting that in RC apoptosis can be activated in any stage of the cell cycle. Further investigations are necessary to understand the peculiar behaviour of tumor cells as well as of ANRC in renal carcinomas as compared to other types of malignancies.

Letters to patients: improving communication in cancer care

Numerous studies have shown that patients are usually dissatisfied with the information they receive during clinical consultations with medical specialists. Therefore, a randomised study design has been used to assess the role of personal letters to patients outlining their cancer consultation. Compared with the control group, patients receiving letters were more satisfied with the amount of information given, and tended to have greater and more accurate recall of the consultation. A survey of referring doctors revealed general support for the idea of sending to cancer patients letters that outline the substance of their consultations. The study shows that letters to patients are a useful method of improving patient satisfaction and recall in clinical consultations. They also provide a permanent record of the consultation, which can be kept for future reference, and encourage greater patient involvement in their care.