The prevalence of BK polyomavirus infection in outpatient kidney transplant recipients followed in a single center.

BACKGROUND: BK polyomavirus (BKV) infection has emerged as an important cause of renal allograft loss. There is no proven therapy, and much basic clinical information is still lacking. METHODS: We serially enrolled 95 outpatient renal transplant recipients (43% of whom were African American) in a single center cross-sectional screening study to determine the prevalence of BKV infection by whole blood polymerase chain reaction, and the prevalence of decoy cells by urinalysis and cytology. We also investigated the demographic and clinical factors associated with BKV infection, and the performance of urinalysis for decoy cells as a screening test for BKV infection. RESULTS: The point prevalence of active BKV viremia was 7.4%. When subjects without active viremia but with a history of viremia and/or nephropathy were included, the overall prevalence was 15.8%. Urinary decoy cells were common, present in 50% of subjects at study entry. Urinalysis for decoy cells as a screen for BKV viremia had a sensitivity of 86%, specificity of 52%, positive predictive value of 13% and negative predictive value of 98%. CONCLUSIONS: Decoy cells on urinalysis were the only factor independently associated with an increased risk of BKV infection on multivariate analysis. Although associated with BKV infection on univariate analysis, thymoglobulin, mycophenolate mofetil, and tacrolimus use were not independently associated with BKV infection on multivariate analysis, neither were history of acute rejection, gender, race, nor cause of end-stage renal disease.

Parathyroidectomy versus cinacalcet hydrochloride-based medical therapy in the management of hyperparathyroidism in ESRD: a cost utility analysis.

BACKGROUND: Previously, patients with end-stage renal disease (ESRD) with uncontrolled hyperparathyroidism had few options other than parathyroidectomy, which was reserved for patients refractory to medical therapy. Newer calcimimetic agents, such as cinacalcet, may be an alternative, but raise the possibility of indefinite medical treatment that also would increase costs. STUDY DESIGN: Cost utility analysis. SETTING & POPULATION: Base case consisted of prevalent adult US patients with ESRD refractory to management with standard medical therapy. Characteristics were obtained from patients who underwent parathyroidectomy in 2001, and, for purposes of comparison, patients in whom cinacalcet was used were assigned similar characteristics. All data came from preexisting literature and trials or from US Renal Data System analysis files. INTERVENTION: Use of cinacalcet hydrochloride versus parathyroidectomy. PERSPECTIVE & TIME FRAME: Medicare and societal costs and quality-adjusted life-years from the date of parathyroidectomy or use of cinacalcet followed up for 2 years, respectively. MODEL & OUTCOMES: Primary outcomes were cost (measured in US dollars) and cost utility measured using cost per quality-adjusted life-years. RESULTS: At base-case surgical and drug costs, surgical and drug success rates, complication rates/costs, and benefit from correction of hyperparathyroidism, parathyroidectomy was found to be both less expensive and more cost-effective at 7.25 +/- 0.25 months. Parathyroidectomy became more cost-effective at 15.28 to 16.32 months at the upper limit of sensitivity analysis, when drug/surgical costs and success/complication rates/costs were maximally weighted to favor cinacalcet-based medical therapy. LIMITATIONS: We assumed current costs of both cinacalcet and parathyroidectomy and assumed cinacalcet use would be indefinite. CONCLUSIONS: For patients with ESRD with uncontrolled hyperparathyroidism who are good candidates for either drug therapy or surgery, cinacalcet hydrochloride is the most cost-effective modality if the patient is to remain on dialysis therapy for 7.25 +/- 0.25 months. Cinacalcet may be more optimal if used in patients who have high risk of mortality or who would expect to receive a kidney transplant quickly. For other subgroups, parathyroidectomy dominated.

Secondary Hypertension, Erythrocytosis, and Unilateral Renal Cystic Disease in a Submariner: A Case Report.

Erythrocytosis, or increased red blood cell mass, may be primary as in the case of polycythemia vera (PV), or secondary due to a variety of causes related to erythropoietin (EPO) secretion and hypoxia. Chronic pulmonary disease and certain EPO-secreting tumors should be addressed and excluded early during the course of evaluation for a patient presenting with increased red blood cell mass. Inclusion of the JAK2 V617F gene mutation in the recent World Health Organization criteria for the diagnosis of PV allows for facilitated diagnosis and guides therapy. EPO levels can be helpful in diagnosis and guiding therapy, but in the case of cystic renal diseases, EPO levels are often not elevated, creating diagnostic uncertainty. This report describes a case of symptoms directly attributable to erythrocytosis in the setting of negative JAK2 mutation and normal EPO levels. The subsequent discovery of a large cystic renal kidney and PV were the leading diagnostic considerations.

Cardiovascular risk in stage 4 and 5 nephropathy.

Severity of heart disease of almost all types, as well as mortality risk associated with heart disease, increases in step with severity of kidney disease, although not necessarily in a linear fashion. Heart failure is more common and just as lethal as ischemic heart disease in patients with severe chronic kidney disease (CKD). The incidence of nonfatal heart disease in dialysis and transplant populations has now been described in detail. Although standard risk factors for heart disease that are more common among patients with CKD than in the general population do not adequately explain the greatly increased risk of heart disease in patients with severe CKD, neither do as yet identified "nontraditional" risk factors. However, in addition to the factors not common in the general population, such as anemia, hyperphosphatemia, and markers of systemic inflammation, patients with CKD in the modern era may also exhibit excessive thrombotic tendencies. Screening for heart disease in this population relies mainly on dobutamine stress echocardiography or nuclear scintigraphy. The role of electron beam CT (EBCT) scanning is currently controversial. The indications for coronary angiography are the same for patients with CKD as for the general population, but patients with CKD are at greatly increased risk for contrast-associated nephropathy, the least controversial preventive therapy, which consists of isotonic saline and N-acetylcysteine. Finally, patients with CKD do not currently receive adequate medical therapy for prevention and treatment of heart disease.

Blastocystis and schistosomiasis coinfection in a patient with chronic kidney disease.

Chronic kidney disease (CKD) and end-stage renal disease (ESRD) represent a spectrum of impaired immunity with effects on cellular immunity, soluble immune factors, and inflammation. As a result, infections due to impaired immune system responses are responsible for significant morbidity in patients with kidney disease. Because of immune dysfunction in CKD, these patients have reduced probability to clear infections and are susceptible to pathogenic effects of common organisms. We present a case of a patient with CKD coinfected with Schistosoma mansoni and Blastocystis spp. This appears to be the first reported association of Schistosoma mansoni and Blastocystis spp. in a patient with CKD.

Cystinuria in a patient with polycystic kidney disease.

Cystinuria is a rare autosomal recessive metabolic disorder of renal and intestinal cystine transport. Cystine stones are found in only 1-2% of all stone formers. Patients with cystinuria are at high risk for nephrolithiasis and subsequent morbidity. Our patient is a 37-year-old male who presented for routine follow-up for polycystic kidney disease (PKD). He denied any history of passing nephroliths. He had no family history of PKD or personal history of kidney stones. Serum creatinine was 1.2 mg%. On routine urine microscopy, he was found to have multiple hexagonal cystine crystals. Urine pH was 7.5. Renal CT scan revealed enlarged polycystic kidneys and scattered bilateral intra-renal calculi. Urinary quantification of cystine was 1645 mg/day (normal excretion rate 30 mg/day). Patients with PKD are at increased risk for nephrolithiasis for a number of reasons including urinary acidification, concentrating defects and hypocitraturia. The molecular, cellular and genetic basis for cystinuria is distinctly different and presumably unrelated to the genetic defects in PKD. We suspect that the occurrence of these two unrelated genetic diseases in the same patient is a coincidental finding. Even after a thorough review of the published literature, we were unable to find a genetic relationship between cystinuria and cystic renal diseases. To our knowledge, this is the first report of a finding of cystinuria in an adult with PKD.

Therapeutic plasma exchange as a nephrological procedure: a single-center experience.

In the United States, therapeutic plasma exchange (TPE) is both performed and requested by a wide range of services, often on an empiric basis (before a diagnosis is established). Whether empiric therapy is beneficial has not been established. Patients were identified from an electronic procedure log that included those patients who received plasmapheresis at Walter Reed Army Medical Center from 1996 to 2003. The clinical indications, referring service, and outcomes (including deaths) that occurred were tabulated. Between March 1997 and August 2003, 568 TPE treatments were performed in 54 patients. The majority of the diagnoses were either neurologic (48%) or hematologic (37%). Thirty-three patients (61%) received TPE for a Category I indication. Twelve cases were performed empirically (without an established diagnosis) at the request of the referring service, most (7) performed for presumed thrombotic thrombocytopenic purpura (TTP). Almost 80% of patients required central venous catheters for treatment. Twelve patients (22%) experienced a major complication including death, and six patients (11%) died. Of the patients who died, 5 (83%) were treated empirically versus one death (17%) among patients not treated empirically, P < 0.001 by Chi Square. Only one of the seven patients treated empirically for TTP died, however. In logistic regression analysis, empiric treatment was the only factor independently associated with death, adjusted odds ratio, 34.2, 95% CI, 3.4, 334.8, P = 0.003. The most common indication for TPE was neurological disease, which also accounted for the highest proportion of complications. With the exception of presumed TTP, performing TPE in the absence of a confirmed diagnosis was not beneficial.