Amr El-Husseini

Can Cystatin C Replace Creatinine to Estimate Glomerular Filtration Rate? A Literature Review

Background: With the increasing knowledge that estimation of glomerular filtration rate (GFR) from serum creatinine (Scr) has limited value, researchers have developed new equations based on serum cystatin C (Cys C). Aim: To compare the performance of serum Cys C and Cys C-based GFR equations to Scr and Scr-based GFR equations. Methods: A Medline literature search for studies in English. Results: Fourteen studies in kidney transplant patients and 29 in patients with native kidney disease were identified. 70% of studies on transplants favored Cys C over Scr while 60% favored serum Cys C over Scr in patients with native kidney disease. Three studies in transplant patients and 6 in patients with native kidney disease compared the performances of Cys C- and Scr-based equations. 70% of the studies performed on transplantation favored Cys C, while 85% the studies performed in native kidney diseases showed superiority of Cys C-based equations. Conclusion: A large number of studies favor Cys C over Scr for the estimation of GFR. Still, many reports show no superiority of Cys C over Scr. Consistent with this, more studies are needed to study the performance of Cys C-based GFR equations.

Preventing Bone Loss in Renal Transplant Recipients with Vitamin D

Very rapid bone loss, osteopenia, and osteoporosis have been documented in the first 6 to 12 mo after renal transplantation. Investigated was the effect of treatment with active vitamin D on the prevention of posttransplantation bone loss. Forty adult men who were recent renal transplant recipients were enrolled onto the study. Patients were randomized into two groups: group 1 received daily alfacalcidol 0.5 micro g by mouth, and group 2 (control) received placebo. Every patient in both groups received daily 500-mg calcium carbonate supplements. Parameters of bone metabolism and bone mineral density measured at three sites were assessed before and after the study period. Bone mineral density was increased by 2.1%, 1.8%, and 3.2% at lumbar spine, femoral neck, and forearm, respectively, in group 1, whereas it decreased by 3.2%, 3.8%, and 1.8% at the same sites in the control group (P < 0.05). Serum intact parathyroid hormone level decreased significantly in group 1 compared with the control group (P = 0.003). Early bone loss that occurs during the first 1 yr after renal transplantation could be prevented by alfacalcidol. Use of alfacalcidol early after transplantation is safe and well tolerated.

Treatment of osteopenia and osteoporosis in renal transplant children and adolescents

Abstract:  Successful renal transplantation corrects many of the metabolic abnormalities associated with the development of renal osteodystrophy, but despite a well‐functioning graft osteopenia, growth failure, spontaneous fractures, and avascular necrosis remain prevalent in adult and pediatric kidney recipients. A paucity of information exists regarding the effects of different therapies to prevent and treat bone loss in the renal transplant recipients. We constructed a design to study the effect of different modalities of treatment on bone mass in our renal transplant children. Among 93 patients who underwent renal transplantation at the age of 17 yr or less and were subjected to dual‐energy X‐ray absorptiometry (DEXA), we blindly randomized 60 patients who had osteopenia or osteoporosis (T‐score = −1 by DEXA) in a prospective study. Their mean age at time of transplantation was 13.4 ± 4.3 yr. The mean duration after transplantation was 48 ± 34 months. The patients were classified randomly into four groups. Each group consisted of 15 patients: group 1 was the control group, group 2 received oral alfacalcidol 0.25 μg daily, group 3 received oral alendronate 5 mg daily, and group 4 received 200 IU/day nasal spray calcitonin. Parameters of bone turnover, calcium metabolism, and DEXA were measured before and after 12 months of treatment duration. The characteristics of all groups were comparable at the beginning of the study. At the lumber spine, bone mass density decreased from −2.4 to −2.8 in group 1, increased from −2.3 to −0.5 in group 2, from −2.3 to −1.9 in group 3, and from −2.3 to −1.0 in group 4. The four groups had similar patient profiles, serum creatinine, intact parathyroid hormone, osteocalcin, and deoxypyridinoline. This study confirmed the value of alfacalcidol and antiresorptive agents in the treatment of osteopenia and osteoporosis in young renal transplant recipients .These therapies were safe, tolerable, simple to administer and potentially applicable to other renal transplant patients.

Echocardiographic changes and risk factors for left ventricular hypertrophy in children and adolescents after renal transplantation

Abstract:  Long‐term consequences of cardiac alteration in children with chronic renal failure and after renal transplantation are largely unknown. In chronic uremia, cardiomyopathy manifests itself as systolic dysfunction, concentric left ventricular hypertrophy (LVH) or left ventricular dilatation. The correction of uremic state by renal transplantation leads to normalization of left ventricular contractility, regression of LVH and improvement of cavity volume and so dialysis patients with uremic cardiomyopathy would benefit from renal transplantation. We studied 73 patients, aged 17 yr or less, who underwent renal transplantation in our center. This cross‐sectional study was performed 4.6 yr (median) after transplantation. Of the total, 48 were males and 25 were females. Transthoracic echocardiographic examination was performed for all cases. The effects of clinical, demographic, biochemical and therapeutic data on echocardiographic parameters were assessed. Multivariate analysis was used to assess the relation between the risk factors and the left ventricular muscle mass index. The most common echocardiographic abnormalities were the LVH (47.9%), left atrial enlargement (31.5%) and left ventricular dilatation and systolic dysfunction (13.7% for each). The pretransplant dialysis, arteriovenous fistula, acute rejection, cumulative steroid dose per square meter surface area, post‐transplant hypertension, anemia and graft dysfunction were significant risk factors for LVH by univariate analysis. The significant factors by multivariate analysis were pretransplant dialysis, post‐transplant hypertension and anemia. From this study we may conclude that LVH is a common problem among renal transplant children and adolescents. Early transplantation, control of hypertension and correction of anemia may be beneficial regarding left ventricular function and structure.

Determinants of graft survival in pediatric and adolescent live donor kidney transplant recipients: a single center experience.

Abstract:  To study the independent determinants of graft survival among pediatric and adolescent live donor kidney transplant recipients. Between March 1976 and March 2004, 1600 live donor kidney transplants were carried out in our center. Of them 284 were 20 yr old or younger (mean age 13.1 yr, ranging from 5 to 20 yr). Evaluation of the possible variables that may affect graft survival were carried out using univariate and multivariate analyses. Studied factors included age, gender, relation between donor and recipient, original kidney disease, ABO blood group, pretransplant blood transfusion, human leukocyte antigen (HLA) matching, pretransplant dialysis, height standard deviation score (SDS), pretransplant hypertension, cold ischemia time, number of renal arteries, ureteral anastomosis, time to diuresis, time of transplantation, occurrence of acute tubular necrosis (ATN), primary and secondary immunosuppression, total dose of steroids in the first 3 months, development of acute rejection and post‐transplant hypertension. Using univariate analysis, the significant predictors for graft survival were HLA matching, type of primary urinary recontinuity, time to diuresis, ATN, acute rejection and post‐transplant hypertension. The multivariate analysis restricted the significance to acute rejection and post‐transplant hypertension. The independent determinants of graft survival in live‐donor pediatric and adolescent renal transplant recipients are acute rejection and post‐transplant hypertension.

Can Donor Implantation Renal Biopsy Predict Long-Term Renal Allograft Outcome?

Background: Donor kidney implantation biopsy (IB) is performed on a regular basis, particularly as part of clinical studies. Objective: To determine the utility of donor implantation renal biopsy to predict the long-term renal allograft outcome. Methods: A Medline search for studies in English was performed with the following key words: implantation biopsy, renal transplantation and long-term outcome. Results: Sixteen trials involving 8,122 kidney transplants were identified, of which 6 were prospective studies. The histological abnormalities were scored mainly by the Banff schema and the graft outcome was defined either by delineating the delta changes in the pathology score or glomerular filtration rate. Normal histology with a well-functioning renal allograft had a favorable outcome. The extent to which the baseline tubular atrophy, interstitial fibrosis, glomerulosclerosis and vascular changes had on the long-term outcome varied from one study to another. Conclusion: Abnormal IB has a better chance of predicting early graft outcome. The review questions the current wisdom for routine IB on all donors. In some donor kidneys, a biopsy provides significant prognostic information, such as older donor kidney, those with history of hypertension, diabetes, cardiovascular disease, and kidneys with abnormal creatinine. Future research on IB is necessary to find a more useful method to predict the long-term transplant outcome.

Surgical complications in live‐donor pediatric and adolescent renal transplantation: Study of risk factors

Abstract:  To report the surgical complications among our pediatric and adolescent renal transplants and to analyze the different factors that may influence the occurrence of such complications. Methods: A total of 250 pediatric and adolescent renal transplants were included in this study. Of these patients, there were 154 boys and 96 girls with a mean age of 15.4±3.7 yr (range 5–20 yr). All patients received their kidneys from living donors. Four patients underwent renal retransplantation. Surgical complications were reported and their incidence was correlated with several pretransplant, technical and post‐transplant risk factors by both univariate and multivariate analyses. The impact of surgical complications on graft and patient survival was computed using the Kaplan–Meier technique. Results: Among the 250 patients, 35 surgical complications were encountered in 33 patients. These complications included urinary leakage in 10 patients, ureteric stricture in 11 patients, complicated lymphocele in eight patients, hematoma necessitating surgical exploration in two patients, wound dehiscence in one patient, stone of the graft ureter in one patient and renal artery stenosis in two patients. The incidence of urological complications (ureteral stenosis, urinary leakage and stone disease) was 8.8% and vascular complications 0.8%. Small ureteric leakage (four patients) was treated by endourologic techniques, whereas leaks associated with ureteral necrosis required open revision. Endourologic treatment was attempted in early and mild cases of ureteric obstruction. In late and severe cases, surgery was performed. On univariate analysis, the factors that significantly affected the incidence of surgical complications were recipients age, lower urinary tract abnormalities, the type of primary urinary recontinuity, the time to diuresis, and height and weight of the patients. On multivariate analysis, the type of primary urinary continuity was the only factor that sustained statistical significance. Neither patient nor graft survival was affected by the occurrence of surgical complications. Conclusion: Primary urinary continuity is the only risk factor that affects the incidence of surgical complications among pediatric and adolescent live donor renal transplants, with the extravesical technique of Lich‐Gregoir providing the best results. Surgical complications in pediatric and adolescent renal transplantation can be minimized if basic principles of careful transplant techniques are used. Prompt identification and treatment of any complication is paramount to graft and patient survival.

A Prospective Randomized Study for the Treatment of Bone Loss with Vitamin D During Kidney Transplantion in Children and Adolescents

The effect of treatment with alfacalcidol on post‐transplantation bone loss in children and adolescents was investigated.

Acute postinfectious crescentic glomerulonephritis: clinicopathologic presentation and risk factors.

Background: Glomerular crescent formation is a feature of the most severe forms of human glomerulonephritis. The postinfectious form of rapidly progressive glomerulonephritis with crescents is a form of immune complex glomerulonephritis which seem to have a better prognosis. A relatively poorer prognosis for crescentic postinfectious glomerulonephritis in South Africa has been reported. In the present study, we have tried to determine the mode of presentation, and the prognostic factors for renal and patient outcome for cases with postinfectious crescentic glomerulonephritis (CGN). Methods:Between 1990 and 2000 a total number of 128 patients with CGN were managed at our center, among them 23 cases were diagnosed as postinfectious CGN. They were followed-up for a mean period of 40.1 ± 28.9 months. Among them 12 were males and 11 were females. The median age was 12.35 years (range 4–55 years). The median serum creatinine at presentation was 7.24 mg/dl (range 1.3–14.5 mg/dl). We studied the clinical, laboratory and histopathological data .of our cases and their impact on the renal and patient outcome. Results:By univariate study the risk factors for renal dysfunction were the age, hypertension, and nephrotic range proteinuria during the follow-up period. By multivariate analysis only the, hypertension, and presence of nephrotic range proteinuria during the follow-up period were the significant risk factors. The risk factors that significantly affected patient mortality were hypertension and serum creatinine at last follow-up. Conclusion: postinfectious CGN is a severe form of glomerulonephritis that usually presents with rapidly progressive renal failure. The persistence of hypertension and nephrotic range proteinuria during the follow-up are major bad prognostic predictors for renal dysfunction.

Is threshold for treatment of methemoglobinemia the same for all? A case report and literature review.

Acquired methemoglobinemia (MetHb) is a rare complication of exposure to toxic chemicals or drugs, most commonly topical anesthetic agents. This condition occurs when the rate of methemoglobin production exceeds the rate of methemoglobin reduction. Topical anesthetics have been reported to cause MetHb, but this adverse event is extremely rare and is not usually listed as one of the possible complications of transesophageal echocardiography (TEE). However, the number of published case reports of TEE-associated MetHb has recently increased. Benzocaine (ethyl aminobenzoate) is a topical anesthetic widely used for oropharyngeal anesthesia before TEE. Health care providers who are not familiar with the association of TEE and benzocaine-induced MetHb may not recognize the idiosyncratic and often nonspecific characteristics of this condition. Recognition is critical, as clinically important symptoms may occur at relatively low MetHb levels. If left untreated, MetHb can lead to cardiopulmonary compromise, severe neurologic impairment, and even death. The current report documents a case of TEE-associated MetHb from a high-volume (3000 cases per year including 300-350 TEEs per year) echo laboratory. Our patient was symptomatic and severely distressed, despite a MetHb level of only 10.8%. This case report emphasizes the importance of early recognition and treatment of MetHb, as it represents a medical emergency and can be severely symptomatic, especially in young children and the elderly, even with low MetHb levels.