Pseudohyponatremia: Mechanism, Diagnosis, Clinical Associations and Management

Pseudohyponatremia remains a problem for clinical laboratories. In this study, we analyzed the mechanisms, diagnosis, clinical consequences, and conditions associated with pseudohyponatremia, and future developments for its elimination. The two methods involved assess the serum sodium concentration ([Na]_S) using sodium ion-specific electrodes: (a) a direct ion-specific electrode (ISE), and (b) an indirect ISE. A direct ISE does not require dilution of a sample prior to its measurement, whereas an indirect ISE needs pre-measurement sample dilution. [Na]_S measurements using an indirect ISE are influenced by abnormal concentrations of serum proteins or lipids. Pseudohyponatremia occurs when the [Na]_S is measured with an indirect ISE and the serum solid content concentrations are elevated, resulting in reciprocal depressions in serum water and [Na]_S values. Pseudonormonatremia or pseudohypernatremia are encountered in hypoproteinemic patients who have a decreased plasma solids content. Three mechanisms are responsible for pseudohyponatremia: (a) a reduction in the [Na]_S due to lower serum water and sodium concentrations, the electrolyte exclusion effect; (b) an increase in the measured sample's water concentration post-dilution to a greater extent when compared to normal serum, lowering the [Na] in this sample; (c) when serum hyperviscosity reduces serum delivery to the device that apportions serum and diluent. Patients with pseudohyponatremia and a normal [Na]_S do not develop water movement across cell membranes and clinical manifestations of hypotonic hyponatremia. Pseudohyponatremia does not require treatment to address the [Na]_S, making any inadvertent correction treatment potentially detrimental.

Combinations of grape seed procyanidin extract and milk thistle silymarin extract against lung cancer - The role of MiR-663a and FHIT

AIMS

Grape seed procyanidin extract (GSE), and milk thistle silymarin extract (MTE) contain structurally distinct polyphenols, and each agent has been shown to exert antineoplastic effects against lung cancer. We hypothesize that combinations of GSE and MTE will additively enhance their anticancer effects against lung cancer.

MATERIALS AND METHODS

The anti-proliferative effects of GSE, MTE and combinations were evaluated in lung neoplastic cell lines. A dose range finding (DRF) study to determine safety, bioavailability and bioactivity, followed by human lung cancer xenograft efficacy studies were conducted in female nude mice with once daily gavage of leucoselect phytosome (LP), a standardized GSE, and/or siliphos, a standardized MTE. The roles of tumor suppressors miR-663a and its predicted target FHIT in mediating the additive, anti-proliferative effecs of GSE/MTE were also assessed.

KEY FINDINGS

GSE with MTE additively inhibited lung preneoplastic and cancer cell proliferations. Mice tolerated all dosing regimens in the DRF study without signs of clinical toxicity nor histologic abnormalities in the lungs, livers and kidneys. Eight weeks of LP and siliphos additively inhibited lung tumor xenograft growth. Plasma GSE/metabolites and MTE/metabolites showed that the combinations did not decrease systemic bioavailabilities of each agent. GSE and MTE additively upregulated miR-663a and FHIT in lung cancer cell lines; transfection of antisense-miR-663a significantly abrogated the anti-proliferative effects of GSE/MTE, upregulation of FHIT mRNA and protein. LP and siliphos also additively increased miR-663a and FHIT protein in lung tumor xenografts.

SIGNIFICANCE

Our findings support clinical translations of combinations of GSE and MTE against lung cancer.

Leucoselect Phytosome Modulates Serum Eicosapentaenoic Acid, Docosahexaenoic Acid, and Prostaglandin E3 in a Phase I Lung Cancer Chemoprevention Study

Grape seed procyanidin extract (GSE) has been shown to exert antineoplastic properties in preclinical studies. Recently, we reported findings from a modified phase I, open-label, dose escalation clinical study conducted to evaluate the safety, tolerability, MTD, and potential chemopreventive effects of leucoselect phytosome, a standardized GSE complexed with soy phospholipids to enhance bioavailability, in heavy active and former smokers. Three months of leucoselect phytosome treatment significantly decreased bronchial Ki-67 labeling index (LI), a marker of cell proliferation on the bronchial epithelium. Because GSE is widely used as a supplement to support cardiovascular health, we evaluate the impact of oral leucoselect phytosome on the fasting serum complex lipid metabolomics profiles in our participants. One month of leucoselect phytosome treatment significantly increased eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the omega-3 polyunsaturated fatty acids (n-3 PUFA) with well-established anticancer properties. Leucoselect phytosome also significantly increased unsaturated phosphatidylcholines (PC), likely from soy phospolipids in the phytosome and functioning as transporters for these PUFAs. Furthermore, 3-month leucoselect phytosome treatment significantly increased serum prostaglandin (PG) E₃ (PGE₃), a metabolite of EPA with anti-inflammatory and antineoplastic properties. Such increases in PGE₃ correlated with reductions of bronchial Ki-67 LI (r = -0.9; P = 0.0374). Moreover, posttreatment plasma samples from trial participants significantly inhibited proliferation of human lung cancer cell lines A549 (adenocarcinoma), H520 (squamous cell carcinoma), DMS114 (small cell carcinoma), and 1198 (preneoplastic cell line). Our findings further support the potential utility of leucoselect phytosome in reducing cardiovascular and neoplastic risks in heavy former and active smokers. PREVENTION RELEVANCE: In this correlative study of leucoselect phytosome for lung cancer chemoprevention in heavy active and former smokers, we demonstrate for the first time, favorable modulations of n-3PUFA and downstream PGE₃ in fasting serum, further supporting the chemopreventive potential of leucoselect phytosome against lung cancer.

A Pilot Study of a Grape Seed Procyanidin Extract for Lung Cancer Chemoprevention

Grape seed procyanidin extract (GSE) had been reported to exert antineoplastic properties in preclinical studies. A modified phase I, open-label, dose-escalation clinical study was conducted to evaluate the safety, tolerability, MTD, and potential chemopreventive effects of leucoselect phytosome (LP), a standardized GSE complexed with soy phospholipids to enhance bioavailability, in heavy active and former smokers. Eight subjects ages 46-68 years were enrolled into the study and treated with escalating oral doses of LP for 3 months. Bronchoscopies with bronchoalveolar lavage and bronchial biopsies were performed before and after 3 months of LP treatment. Hematoxylin and eosin stain for histopathology grading and IHC examination for Ki-67 proliferative labeling index (Ki-67 LI) were carried out on serially matched bronchial biopsy samples from each subject to determine responses to treatment. Two subjects were withdrawn due to issues unrelated to the study medication, and a total of 6 subjects completed the full study course. In general, 3 months of LP, reaching the highest dose per study protocol was well tolerated and no dosing adjustment was necessary. Such a treatment regimen significantly decreased bronchial Ki-67 LI by an average of 55% (P = 0.041), with concomitant decreases in serum miR-19a, -19b, and -106b, which were oncomirs previously reported to be downregulated by GSE, including LP, in preclinical studies. In spite of not reaching the original enrollment goal of 20, our findings nonetheless support the continued clinical translation of GSE as an antineoplastic and chemopreventive agent against lung cancer.

Grape seed procyanidin extract against lung cancer: the role of microrna-106b, bioavailability, and bioactivity

MiR-106b is an oncomir and a potential target for anti-cancer therapy. We hypothesize that grape seed procyanidin extract (GSE) exerts antineoplastic effects on lung cancer through modulations of miR-106b and its downstream target. We found that GSE significantly down-regulated miR-106b in a variety of lung neoplastic cells and increased cyclin-dependent kinase inhibitor 1A (CDKN1A) mRNA and protein (p21) levels. Transfection of miR-106b mimics reversed the up-regulations of CDKN1A mRNA and p21, abrogated the GSE induced anti-proliferative and anti-invasive properties in lung cancer cells. Oral gavage of leucoselect phytosome (LP), a standardized GSE to athymic nude mice down-regulated MIR106B mRNA and miR-106b expressions, and increased CDKN1A mRNA expression in tumor xenografts, correlating to significant reduction of tumor growth. To assess bioavailability, GSE and metabolites in plasma levels, between 60-90 minutes after gavage of LP were measured by LC/MS at treatment week 4 and 8. A novel bioactivity assay was also developed using lung homogenates from treated mice co-cultured with human lung cancer cells. LP-treated mouse lung homogenates significantly reduced proliferations of various lung cancer cells. Our findings reveal novel antineoplastic mechanisms by GSE, further define the pharmacokinetics and pharmacodynamics of LP, and support the continued investigation of LP against lung cancer.

Chronic Nephropathy from Dietary Hyperoxaluria: Sustained Improvement of Renal Function after Dietary Intervention

A 56-year-old man with stable chronic kidney disease (CKD) for two years following a single episode of calcium oxalate urolithiasis developed progressive elevation of his serum creatinine concentration. Urinalysis revealed pyuria and white cell casts, a few red blood cells, minimal proteinuria, and no crystals. Urine culture was sterile. Gallium scintigraphy was consistent with interstitial nephritis. Proton pump inhibitor intake was discontinued, and a short course of oral corticosteroids was initiated. Percutaneous kidney biopsy, performed because of the continued deterioration of renal function to a minimum estimated glomerular filtration rate (eGFR) value of 15 mL/min per 1.73 m² and persistent pyuria, revealed deposition of oxalate crystals in the tubules and interstitium, pronounced tubular changes, and interstitial nephritis and fibrosis. Urinary oxalate excretion was very high, in the range usually associated with primary hyperoxaluria. However, investigations for primary or enteric hyperoxaluria were negative. He reported a diet based on various nuts high in oxalate content. Estimated oxalate content in the diet was, for years, approximately four times higher than that in the average American diet. The institution of a diet low in oxalates resulted in the rapid normalization of urinary oxalate excretion and urinary sediment and in the slow, continuous improvement of renal function to near normal levels (eGFR 59 mL/min/1.73 m²) before his death from a brain malignancy 3.5 years later. The manifestations of nephropathy secondary to dietary hyperoxaluria, including the urine findings, can be indistinguishable from other types of interstitial nephritis. The diagnosis of dietary hyperoxaluria requires careful dietary history and a kidney biopsy. Identifying dietary hyperoxaluria as the cause of CKD is important because the decrease in dietary oxalate intake without any other measures can lead to sustained improvement in renal function.

Physician Satisfaction With Clinical Laboratory Services: A College of American Pathologists Q-Probes Study of 81 Institutions

CONTEXT

-Assessment of customer satisfaction is a vital component of the laboratory quality improvement program.

OBJECTIVE

-To survey the level of physician satisfaction with hospital clinical laboratory services.

DESIGN

-Participating institutions provided demographic information and survey results of physician satisfaction, with specific features of clinical laboratory services individually rated on a scale of 5 (excellent) to 1 (poor).

RESULTS

-Eighty-one institutions submitted 2425 surveys. The median overall satisfaction score was 4.2 (10th percentile, 3.6; 90th percentile, 4.6). Of the 16 surveyed areas receiving the highest percentage of excellent/good ratings (combined scores of 4 and 5), quality of results was highest along with test menu adequacy, staff courtesy, and overall satisfaction. Of the 4 categories receiving the lowest percentage values of excellent/good ratings, 3 were related to turnaround time for inpatient "STAT" (tests performed immediately), outpatient STAT, and esoteric tests. The fourth was a new category presented in this survey: ease of electronic order entry. Here, 11.4% (241 of 2121) of physicians assigned below-average (2) or poor (1) scores. The 5 categories deemed most important to physicians included quality of results, turnaround times for inpatient STAT, routine, and outpatient STAT tests, and clinical report format. Overall satisfaction as measured by physician willingness to recommend their laboratory to another physician remains high at 94.5% (2160 of 2286 respondents).

CONCLUSIONS

-There is a continued trend of high physician satisfaction and loyalty with clinical laboratory services. Physician dissatisfaction with ease of electronic order entry represents a new challenge. Test turnaround times are persistent areas of dissatisfaction, representing areas for improvement.

MicroRNA-19a/b mediates grape seed procyanidin extract-induced anti-neoplastic effects against lung cancer

Oncomirs are microRNAs (miRNA) associated with carcinogenesis and malignant transformation. They have emerged as potential molecular targets for anti-cancer therapy. We hypothesize that grape seed procyanidin extract (GSE) exerts antineoplastic effects through modulations of oncomirs and their downstream targets. We found that GSE significantly down-regulated oncomirs miR-19a and -19b in a variety of lung neoplastic cells. GSE also increased mRNA and protein levels of insulin-like growth factor II receptor (IGF-2R) and phosphatase and tensin homolog (PTEN), both predicted targets of miR-19a and -19b. Furthermore, GSE significantly increased PTEN activity and decreased AKT phosphorylation in A549 cells. Transfection of miR-19a and -19b mimics reversed the up-regulations of IGF2R and PTEN gene expression and abrogated the GSE induced anti-proliferative response. Additionally, oral administration of leucoselect phytosome, comprised of standardized grape seed oligomeric procyanidins complexed with soy phospholipids, to athymic nude mice via gavage, significantly down-regulated miR-19a, -19b and the miR-17-92 cluster host gene (MIR17HG) expressions, increased IGF-2R, PTEN, decreased phosphorylated-AKT in A549 xenograft tumors, and markedly inhibited tumor growth. To confirm the absorption of orally administered GSE, plasma procyanidin B1 levels, between 60 and 90 min after gavage of leucoselect phytosome (400 mg/kg), were measured by LC/MS at week 2 and 8 of treatment; the estimated concentration that was associated with 50% growth inhibition (IC50) (1.3 μg/mL) in vitro was much higher than the IC50 (0.032-0.13 μg/ml) observed in vivo. Our findings reveal novel antineoplastic mechanisms by GSE and support the clinical translation of leucoselect phytosome as an anti-neoplastic and chemopreventive agent for lung cancer.

Discrepancy between Measured Serum Total Carbon Dioxide Content and Bicarbonate Concentration Calculated from Arterial Blood Gases

Large differences between the concentrations of serum total carbon dioxide (TCO2) and blood gas bicarbonate (HCO3 (-)) were observed in two consecutive simultaneously drawn sets of samples of serum and arterial blood gases in a patient who presented with severe carbon dioxide retention and profound acidemia. These differences could not be explained by the effect of the high partial pressure of carbon dioxide on TCO2, by variations in the dissociation constant of the carbonic acid/bicarbonate system or by faults caused by the algorithms of the blood gas apparatus that calculate HCO3 (-). A recalculation using the Henderson-Hasselbach equation revealed arterial blood gas HCO3 (-) values close to the corresponding serum TCO2 values and clarified the diagnosis of the acid-base disorder, which had been placed in doubt by the large differences between the reported TCO2 and HCO3 (-) values. Human error in the calculation of HCO3 (-) was identified as the source of these differences. Recalculation of blood gas HCO3 (-) should be the first step in identifying the source of large differences between serum TCO2 and blood gas HCO3 (-).

Nephropathy in dietary hyperoxaluria: A potentially preventable acute or chronic kidney disease

Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis, but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma, profound tubular damage and interstitial inflammation and fibrosis. Hyperoxaluric nephropathy presents clinically as acute or chronic renal failure that may progress to end-stage renal disease (ESRD). This sequence of events, well recognized in the past in primary and enteric hyperoxalurias, has also been documented in a few cases of dietary hyperoxaluria. Estimates of oxalate intake in patients with chronic dietary hyperoxaluria who developed chronic kidney disease or ESRD were comparable to the reported average oxalate content of the diets of certain populations worldwide, thus raising the question whether dietary hyperoxaluria is a primary cause of ESRD in these regions. Studies addressing this question have the potential of improving population health and should be undertaken, alongside ongoing studies which are yielding fresh insights into the mechanisms of intestinal absorption and renal excretion of oxalate, and into the mechanisms of development of oxalate-induced renal parenchymal disease. Novel preventive and therapeutic strategies for treating all types of hyperoxaluria are expected to develop from these studies.

Favorable outcome of Fournier gangrene in two patients with diabetes mellitus on continuous peritoneal dialysis

Fournier gangrene (FG), a form of necrotizing fasciitis of the perineum and genitals, with high morbidity and mortality in the general population, carries the additional risk of involvement of the peritoneal catheter tunnel and peritoneal cavity in patients on chronic peritoneal dialysis (PD). We describe two men with diabetes who developed FG in the course of PD. Computed tomography showed no extension of FG to the abdominal wall, and spent peritoneal dialysate was clear in both patients. Broad-spectrum antibiotic therapy with anaerobic coverage and early aggressive debridement followed by negative-pressure wound therapy and repeated debridement led to improvements in clinical status in both cases. Surgical closure and healing of the wound was achieved in one patient; the wound of the second patient is healing, but remains open. Both patients experienced prolonged hospitalization, with a serious decline in nutrition status. In patients on PD, FG can be treated successfully. However, additional measures are required to evaluate for potential involvement of the PD apparatus and the peritoneal cavity in the infectious process; and prolonged hospitalization, worsening nutrition, and multiple surgical interventions can result.

Sternal osteomyelitis caused by Aspergillus fumigatus following cardiac surgery: Case and review

Postsurgical sternal wound infection is a serious post-operative complication of cardiac surgery. Aspergillus infection of the sternum is extremely rare. We describe a case of sternal infection due to Aspergillus in an immunocompetent patient following aortic valve replacement.

Acute subdural hematoma following halo pin tightening in a patient with bilateral vertebral artery dissection

We report the first case of acute subdural hematoma (SDH) developing after tightening the halo of an osteoporotic 61-year-old woman on warfarin therapy for bilateral traumatic vertebral artery dissection. We discuss literature relevant to this case with an emphasis on identifying warning signs, including recurrent pin loosening, especially in patients with compromised bone structure and high risk of bleeding. Our 61-year-old patient presented to neurosurgery clinic for a 2-month follow-up of a type-III odontoid fracture sustained in a motor vehicle accident. The patient had repeatedly loosened halo pins, and shortly after the pins were tightened, the patient had a syncopal event and struck her head. An emergent computed tomography scan revealed acute SDH requiring emergent craniotomy and evacuation. SDH following pin penetration in a patient with bilateral vertebral artery dissection, osteoporosis, and anticoagulation has not been reported as a complication of the use of the halo vest for stabilization of the cervical spine. The risk of this serious complication can be minimized by giving special consideration to patients with comorbidities and by repositioning problematic pins. This case demonstrates the importance of special attention to bone strength, bleeding risk, and recurrent minor complaints with use of the halo vest.

Early Aspergillus pacemaker pocket infection: Case and review

We report the first case to our knowledge of an early pacemaker pocket infection due to Aspergillus fumigatus. Several cases of late pacemaker pocket infection by Aspergillus have been reported, but it remains exceedingly rare. Recognition of Aspergillus infection as a potential early or late complication of placement of pacemakers or implantable cardioverter defibrillator devices may help clinicians diagnose and treat future cases of this potentially devastating infection.

Fatal disseminated Cryptococcus gattii infection in New Mexico

We report a case of fatal disseminated infection with Cryptococcus gattii in a patient from New Mexico. The patient had no history of recent travel to known C. gattii-endemic areas. Multilocus sequence typing revealed that the isolate belonged to the major molecular type VGIII. Virulence studies in a mouse pulmonary model of infection demonstrated that the strain was less virulent than other C. gattii strains. This represents the first documented case of C. gattii likely acquired in New Mexico.

A system-based intervention to improve colorectal cancer screening uptake

OBJECTIVE

To determine whether mailing guaiac-based fecal occult blood tests (gFOBTs) directly to patients who are due for colorectal cancer screening would achieve higher screening uptake than using visit-based screening.

STUDY DESIGN

Comparative effectiveness analysis.

METHODS

We used an electronic medical record to identify 7053 New Mexico Veterans Affairs Health Care System patients aged 50 to 80 years who were due for screening in 2008. We invited 3869 randomly selected patients to participate in a randomized controlled trial comparing adherence with different fecal blood tests; 202 intervention patients were assigned to receive mailed gFOBTs. We identified the following 3 control groups who could receive only visit-based colorectal cancer screening: 3184 individuals who were not invited for the randomized controlled trial (control group 1), 2525 individuals who did not respond to invitations to participate in the randomized controlled trial (control group 2), and 255 individuals who could not be contacted (control group 3). We measured gFOBT screening within 3 months after enrollment in the intervention group, as well as gFOBT or colonoscopy screening within 6 months of identification as a control subject. We compared screening across groups using multivariate logistic regression analysis to adjust for sex, race/ethnicity, clinic site, previous gFOBT, and comorbidities.

RESULTS

Colorectal screening occurred less often in each of the control groups (in 18.6% of control group 1, in 14.3% of control group 2, and in 18.8% of control group 3) than among patients mailed a gFOBT (48.5%). Adjusted odds ratios for screening among the control groups were all less than in the intervention group (adjusted odds ratios, 0.25, 0.19, and 0.23, respectively; all, P <.001).

CONCLUSION

Using an electronic medical record to identify screening-eligible patients and mailing them gFOBT cards achieved higher colorectal screening uptake than performing visit-based screening.

Colorectal cancer screening adherence is higher with fecal immunochemical tests than guaiac-based fecal occult blood tests: a randomized, controlled trial

OBJECTIVES

Determine whether colorectal cancer screening adherence is greater with fecal immunochemical tests (FIT) or guaiac-based fecal occult blood tests (gFOBT).

METHODS

We used electronic health records to identify 3869 New Mexico Veterans Affairs Health Care System primary care patients due for screening in 2008 for whom fecal blood testing was appropriate. We invited randomly selected patients by mail to participate in a study comparing FIT and gFOBT. We randomly allocated 404 subjects to receive FIT (n=202) or gFOBT (n=202) by mail. We determined the proportion of subjects completing testing within 90days of agreeing to participate in the study. We also used multivariate logistic regression to evaluate screening completion, adjusting for age, gender, race/ethnicity, clinic site, previous gFOBT testing, and co-morbidity.

RESULTS

Screening adherence was higher with FIT than gFOBT (61.4% vs. 50.5%, P=0.03). The adjusted odds ratio for completing FIT vs. gFOBT was 1.56, 95% CI 1.04, 2.32.

CONCLUSION

In a clinic setting of patients who were due for colorectal cancer screening, adherence was significantly higher with FIT than gFOBT.

Severe proximal myopathy in advanced renal failure. Diagnosis and management

Myopathies encountered in uremic patients may have different pathogenetic mechanisms and treatment. Secondary hyperparathyroidism may cause uremic myopathy responding to specific treatment. This study aimed at presenting a case illustrative of the clinical features, diagnosis and management of uremic parathyroid myopathy. A 66-year old man with renal failure from membranous nephropathy developed sensory signs of uremic neuropathy and progressive painless weakness of the pelvic girdle muscles bilaterally. Motor nerve conduction velocity was normal, electromyogram was consistent with a myopathic pattern, while muscle biopsy showed a pattern of atrophy more consistent with a neuropathic pattern. Serological tests for collagen vascular diseases and hyperthyroidism were negative, while serum muscle enzymes were not elevated and serum phosphate levels were not low. Serum parathyroid hormone level was grossly elevated, while serum calcium was mildly elevated in a small fraction of the measurements, serum alkaline phosphatase showed a progressive rise and skeletal bone survey did not disclose osteopenia or signs of parathyroid bone disease. A course of calcitriol failed to improve the myopathy, which responded promptly and dramatically to parathyroidectomy. Uremic parathyroid myopathy, which has a characteristic clinical picture, must be differentiated from other neuropathic or myopathic conditions that require specific treatments. Progressive parathyroid myopathy is, by itself, an indication for parathyroidectomy, which is curative in this case.

The role of women in mental health care in 19th century England

The history of women's role in the care of mentally ill people is relatively unchartered territory. Women were involved in mental health care in a variety of ways and at the beginning of the 19th century they could operate in capacities equal in status to those of men. Social policies which gave legal backing to medical authority; the rise of medical professionalism, which until the last quarter of the century excluded women; the Victorian ideology which fixed women in a subservient role, all served to ensure that their contribution to the care of mentally ill people was subordinate to that of men. This was reflected in the duties they undertook and their rates of pay, which were always less than those of men.