Morton Kleiner

Diagnosis of iron deficiency anemia in renal failure patients during the post-erythropoietin era

The purpose of this study was to evaluate the sensitivity and specificity of laboratory methods in the diagnosis of posterythropoietin-era, iron-deficient, chronic renal failure patients. The patient population comprised 25 anemic (hemoglobin < 11 g/dL) patients with creatinine greater than 3 mg/dL; 20 were dialysis patients, two were transplant patients, and three patients had renal failure from other causes. Criteria for study inclusion were as follows: bone marrow iron was the reference standard and was graded 0 to +4, ranging from absent to diffuse homogeneous iron staining; serum ferritin concentration and serum transferrin saturation were tested in terms of sensitivity and specificity. The reference standard indicated that iron deficiency existed in 40% of patients. Neither serum ferritin nor transferrin saturation were completely adequate diagnostic tools. Serum ferritin levels less than 200 ng/dL were 100% specific for the diagnosis but only 41% sensitive. Transferrin saturation of less than 20% was 88% sensitive, but only 63% specific. By excluding patients with hypoproteinemia (transferrin values of < 150 mg/dL), the sensitivity of the test increased to 100% and the specificity to 80%. We conclude that transferrin saturation is an adequate screening tool in anemic chronic renal failure patients, provided that hypoproteinemia is not present. By determining both the serum ferritin concentration and the transferrin saturation, a high sensitivity and specificity can be achieved, even in patients with hypoproteinemia. Furthermore, we believe that on this basis, iron therapy in patients with renal insufficiency can be improved.

Heavy chain deposition disease: The disease spectrum

A 45-year-old white woman was found to have microscopic hematuria during her annual physical examination. After a negative urologic workup, she returned 5 months later with nephrotic syndrome, renal insufficiency, and hypocomplementemia. Renal biopsy showed a nodular sclerosing glomerulopathy that could not be further characterized because of inadequate tissue for immunofluorescence. The patient returned 8 months later with chronic renal failure. A repeat renal biopsy showed deposits composed of immunoglobulin G (IgG) heavy chain and complement components C3 and C1 along glomerular, tubular, and vascular basement membranes, with negativity for kappa and lambda light chains, findings consistent with heavy chain deposition disease (HCDD). The heavy chain subclass was exclusively IgG3. Staining with monoclonal antibodies to epitopes of the constant domains of IgG heavy chain showed a CH1 deletion, indicating a truncated heavy chain. On review of the previously reported cases of HCDD, common clinical presentations include nephrotic syndrome, renal insufficiency, hematuria, and, in some cases, hypocomplementemia. In most patients, the hematologic disorder is mild, without overt myeloma. Light microscopy shows a nodular sclerosing glomerulopathy, and heavy chain deposits are detectable within basement membranes throughout the kidney by immunofluorescence and electron microscopy. There is no effective treatment for this condition, and virtually all patients progress to chronic renal failure.

Effect of hemodialysis on the signal-averaged electrocardiogram

The presence of late potentials (LPs) on signal-averaged electrocardiography (SAECG) is predictive of ventricular tachycardia. The effect of hemodialysis (HD) on SAECG has not been well studied. SAECG was evaluated in 28 patients with chronic renal failure immediately before and after HD. In each SAECG, QRS duration, low-amplitude signal duration (LASd), and root-mean-square voltage of the terminal 40 milliseconds of the QRS (RMS40) were measured. To evaluate the effect of fluid removal on SAECG, the last 12 patients were studied during two different HD sessions, one with and one without fluid removal. Two-dimensional echocardiography was performed before and after HD on these 12 patients. At baseline, four patients met the criteria for LPs on SAECG. Only one patient met the criteria for LPs on SAECG after HD. After HD, the mean LASd decreased (28.3 +/- 12.9 to 24.9 +/- 10.1 milliseconds; P = 0.041) and RMS40 increased (63.0 +/- 56.9 to 79.0 +/- 59.2 microV; P = 0. 006). Among the 12 patients who underwent HD with and without fluid removal, left ventricular end-diastolic dimension decreased with (5. 4 +/- 0.6 to 5.1 +/- 0.6 cm; P = 0.024) but not without fluid removal (5.2 +/- 0.3 to 5.1 +/- 0.4 cm; P = not significant [NS]). RMS40 improved with (43.8 +/- 23.1 to 53.2 +/- 22.6 microV; P = 0. 03) but not without fluid removal (51.0 +/- 26.5 to 51.5 +/- 24.2 microV; P = NS). A significant negative correlation was found between change in body weight and change in RMS40 parameter (r = 0. 456; P = 0.0381). SAECG parameters are abnormal in a significant proportion of patients with chronic renal failure and improve with HD despite electrolyte and other proarrhythmic changes. Decreased left ventricular dimension because of fluid removal during HD is one possible explanation for this improvement.

Breast cancer screening in women with chronic kidney disease: the unrecognized effects of metastatic soft-tissue calcification

Patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD) are known to develop metastatic soft-tissue calcification, secondary to hyperparathyroidism, in tissues including the breast. Such calcifications in women could pose a problem for interpretation of mammograms, since they are thought to mimic malignant lesions and interfere with differentiation of benign from malignant disease. Investigation of this issue is important to provide high-quality, accurate breast care to women with CKD or ESRD, but little evidence is so far available. In a systematic review of the literature on the types and patterns of breast calcifications, we found only three studies that examined metastatic soft-tissue calcifications of the breast. The studies did, however, confirm that women with CKD or ESRD have a higher frequency of breast calcification than women with normal kidney function. The two older studies reported that these breast calcifications are not associated with malignancy, but the later study reported a raised rate of suspicious breast calcification among women with ESRD receiving hemodialysis, leading to an increased biopsy referral rate. In this Review we discuss the strengths and limitations of the available data and whether mammography is recommended in women with CKD or ESRD.

Association Between Coronary Artery Disease Diagnosed by Coronary Angiography and Breast Arterial Calcifications on Mammography: Meta-Analysis of the Data

BACKGROUND Previous studies evaluating breast arterial calcifications (BAC) as a risk marker for coronary artery disease (CAD) have been limited by sample size and have yielded mixed results. Our objective was to evaluate the association of BAC and CAD. METHODS Data sources included Medline (1970-2010), the Cochrane Controlled Trials Register electronic database (1970-2010), and CINAHL (1970-2010). The search strategy included the keywords, breast artery calcification, vascular calcification on mammogram, coronary angiography, and meta-analysis. Eligible studies included female patients who had undergone coronary angiography, the gold standard for diagnosing CAD, and had screening mammograms that revealed the presence or absence of BAC. Information on eligibility criteria, baseline characteristics, results, and methodologic quality was extracted by two reviewers. Disagreements were resolved by consensus. RESULTS A total of 927 patients were enrolled in the five studies. There was a 1.59 (95% confidence interval [CI] 1-21-2.09) increased odds of angiographically defined CAD in patients with BAC seen on mammography. CONCLUSIONS The presence of BAC on mammography appears to increase the risk of having obstructive CAD on coronary angiography; thus, BAC may not be a benign finding.

Severe hyperkalemia in a geriatric patient receiving standard doses of trimethoprim-sulfamethoxazole

A case is reported of a 96-year-old woman with congestive heart failure, hypertension, and chronic obstructive pulmonary disease who presented with altered mental status and severe hyperkalemia, a serum potassium 9.3 meq/L, and electrocardiograph changes. The patient was discharged 1 week prior, with a normal serum potassium, receiving trimethoprim-sulfamethoxazole for urinary tract infection and pneumonia. Serum potassium measurements returned to normal after discontinuation of the drug. Other causes of hyperkalemia were ruled out. Mild hyperkalemia due to trimethoprim-sulfamethoxazole was first reported in 1983 in a 69-year-old woman in whom leukemia with leukopenia developed. In literature to date, mild hyperkalemia in younger geriatric patients has been described. Trimethoprim is thought to act by inhibiting amiloride sensitive sodium channels in the distal nephron and impairing renal potassium secretion in a dose dependent manner. The authors report the case, review the literature, and discuss age-related reduction in renal function as a possible etiology.

Erythropoietin and Abnormal Hair Growth in Hemodialysis Patients

To the Editor: The use of recombinant human erythropoietin (r-HuEPO) in chronic renal failure has offered considerable improvements in quality of life, but has also caused some adverse reactions. 1-3 It can cause an increase in blood pressure, headaches, and seizure activity, and an increased rate of clotted vascular accesses.2,4 We found that in our initial 37 patients on hemodialysis receiving r-HuEPO (Epogen, Amgen, Thousand Oaks, CAl, five (13%) had evidence of abnormal hair growth. The patients had received 2,000 to 4,000 U of Epogen intravenous push three times weekly for an average of 8 months. All five of our patients experienced moderate hair growth on some or all of their extremities. None had increased hair on the face or trunk, and the hair was of terminal type. The four women in the group showed no other signs of virilization. Along with the usual medications of the end-stage renal disease patient, some of our patients were also taking insulin, famotidine, nortriptyline, lactulose, ranitidine, and lorazepam. These medications are not known for causing hirsutism. Hair growth is influenced both by the levels of circulating androgens and the peripheral conversion of weaker androgens to testosterone or dihydrotestosterone by 5a-reductase. In addition, the target tissue, the hair follicle, must have androgen receptors to mediate the action of the hormone.s The effect of erythropoietin on androgen levels. or androgen receptors has not been reported. Erythropoietin has been shown to lower the levels of cortisol,6 and high levels of cortisol have been shown to inhibit follicular activity. 5 It would be interesting to investigate whether the erythropoietin-induced decrease in cortisol levels leads to increased hair growth by removing cortisols inhibition of follicular activity. In addition, a decrease in cortisol level may stimulate a compensatory increase in androgens as occurs in congenital adrenal hyperplasia. However, the distribution of hair growth in our patients was not of the classical excess androgen type. The growth on the extremities was moderate and there was none on the face or trunk. Longer follow-up will be required to see if these signs of androgen-induced hirsutism do appear. It may be reasonable to consider that the correction of anemia with r-HuEPO may afford greater blood flow to the follicles, resulting in increased hair growth. However, it has been shown that treatment with r-HuEPO does not increase cutaneous blood flow,? and that the correction of anemia actually causes decreased blood flow to the extremities via vasoconstriction: The mechanism underlying the effect ofr-HuEPO on hair growth needs further elucidation.

Curcumin Potentiates The Ability of Sunitinib to Eliminate the VHL-lacking Renal Cancer Cells 786-O: Rapid Inhibition of Rb Phosphorylation as a Preamble to Cyclin D1 Inhibition

Curcumin, an important component of the culinary spice turmeric, has been shown to harbor anticancer properties against a wide range of cancer cells with minimal toxicity toward normal cells. Two general tyrosine kinase inhibitors (TKIs) sunitinib and sorafenib are currently used in treating renal cancer. Though the use of these TKIs has significantly improved survival, both elicit distressing side effects, limiting their long-term use. We tested the activity of sunitinib and sorafenib to eliminate 786-O renal cancer cells and the efficacy of curcumin to enhance this process. A four-fold decrease in the IC50 of sunitinib, from 4.5 μM to 1.2 μM, was observed in the presence of 20-μM curcumin. However, curcumin did not potentiate the activity of sorafenib. The sunitinib-curcumin (SunC) combination sharply inhibited hyperphosphorylation of the tumor suppressor protein Rb within 8 hours of SunC treatment. Although the levels of cyclin D1 did not change in 8 hours, its expression was dramatically inhibited after 24 hours of SunC exposure. Since curcumin is known to inhibit the cyclin D1-dependent G1/S-phase kinase CDK4 and the cyclin B-dependent G2/M-phase kinase CDK1 that catalyze phosphorylation-mediated inactivation of Rb, our results indicate that SunC containing a lower dose of sunitinib would be effective in restoring the tumor suppressor activity of Rb, thereby truncating cell cycle and triggering cell death. Our results submit the possibility of using SunC as an effective antitumor formulation to reduce the dose and risk of adverse effects of sunitinib.

Effect of hepatitis C virus infection on erythropoiesis in patients on hemodialysis

Background Erythropoietin is a hormone that regulates erythropoiesis and is mainly produced by the kidneys. Several animal studies as well as a few case reports and case series have demonstrated that regenerating hepatic tissue can produce more erythropoietin than normal hepatic tissue. The purpose of the study was to examine the difference in hemoglobin and hematocrit levels as well as epoetin dosage in patients on hemodialysis with and without hepatitis C (HCV). Methods A retrospective chart review was performed. Seventy-six patients were included in the study (19 with HCV and 57 without HCV) at a ratio of 1:3. Exclusion criteria were a history of gastrointestinal bleeding or blood transfusion over the previous six months, polycystic kidney disease, and pregnancy. Variables examined included gender, age, duration of hemodialysis, hemoglobin, hematocrit, epoetin dose, aspartate transaminase, and ferritin levels over a three-month period. Results The patients were divided into two groups. The first consisted of patients with HCV on hemodialysis and the second of patients on hemodialysis without HCV. Mean hemoglobin was 12.6 ± 1.2 g/dL for the HCV-positive group and 11.9 ± 1.1 g/dL for the HCV-negative group. The difference was statistically significant (P = 0.03). Mean hematocrit was higher in the HCV-positive group, but was not significantly different at 39.08% ± 4.06% versus 37.43% ± 3.4% in the HCV-negative group (t-test, P = 0.11). Further, the HCV-positive group required less epoetin, but this was not significantly different from that required in the HCV-negative group at 6258 ± 5208 IU versus 7596 ± 7056 IU, respectively (t-test, P = 0.38). Conclusion In our study, patients with HCV infection were found to have higher hemoglobin and hematocrit levels and lower epoetin requirements than those without HCV. Although the findings were not statistically significant, the computed values between these two groups of patients did follow a general trend. Further investigation with more patients, a longer duration of follow-up, and incorporation of additional medical variables is needed to clarify the role of HCV on erythropoiesis in hemodialysis patients.

Male human papillomavirus infection post-kidney transplant: an overlooked disease

While immunosuppressive regimens improve the overall survival of renal transplant recipients, they also contribute to the long-term complications of post-transplant malignancies. Chronic immune suppression in renal transplant recipients (RTR) increases the risk of viral-associated cancers. In male RTR, human papillomavirus (HPV) is implicated in the development of penile, anal, oropharyngeal, and non-melanoma skin carcinomas. Despite the significance of this virus in RTR, there is an overall deficiency in the understanding of the natural history of HPV infection in male RTR. In the next 20 years, it is believed that cancers will be the leading cause of death in kidney transplant recipients. HPV-associated carcinomas are of particular interest since they are sexually transmitted and in theory may be preventable diseases. This commentary highlights some of the progress made in understanding how HPV is transmitted amongst couples in the general population. It also summarizes the current knowledge of HPV infection in male RTR and describes the deficiencies in published medical literature.