Challenges of implementing point-of-care testing (POCT) glucose meters in a pediatric acute care setting

OBJECTIVES: To investigate factors contributing to analytical bias in POCT glucose values generated by the NICU versus the core laboratory. METHODS: The LifeScan Flexx hospital system glucose meters (SureStep) were used in precision and comparison studies between the NICU and laboratory (ABL715 and Vitros 950). RESULTS: Analysis of 40 neonatal blood samples revealed a positive bias between the NICU glucose meters versus either the laboratory glucose meter or instrument (mean difference of 0.28 and 0.21 mmol/L, respectively). Linear regression analysis (R2 = 0.0584) of the difference in glucose results versus time elapsed between measurements indicated that the bias observed between the NICU and laboratory glucose meters was not due to in vitro glycolysis for samples transported on ice. Further analysis indicated that the bias appeared to be mostly operator driven, with different NICU operators exhibiting different mean biases. Increasing the amount of blood applied to the SureStep Pro test strip (e.g., 60 vs. 20 microL), led to higher values for glucose concentration for the same blood. Nearly 50% of all glucose values reported for the NICU were obtained by the SureStep Flexx glucose meters in a 3-month period following the introduction of POCT, yet the number of laboratory-reported glucose results for the same period increased by 21% as compared to the previous year. CONCLUSIONS: Operator error appears to be a source of bias present between the NICU and laboratory, and despite glucose meter utilization in the NICU, the number of glucose measurements by the central laboratory increased after POCT introduction.     

Hemocompatibility of high strength oxide ceramic materials: an in vitro study

High strength oxide ceramic materials like alumina and zirconia are frequently used for artificial joints because of their biocompatibility and high wear resistance. Their suitability as materials for implants and biomedical devices with direct blood contact, such as cardiovascular implants or components for blood pumps and dialyzers, has not been confirmed to date. The objective of this study was to investigate whether oxide ceramics show sufficient hemocompatibility. Dense specimens were made out of alumina, zirconia, titanium oxide, and aluminum titanate. Polyvinylchloride and silicone were additionally tested as reference materials. Interactions of human blood with the surfaces were studied by investigating partial thromboplastin time (PTT), thrombin antithrombin III complex (TAT), free plasma hemoglobin concentration, complete blood count, complement factor 5a, and protein adsorption. The results from the PTT and TAT tests clearly indicated higher blood activation by the ceramic materials when compared to the two polymer materials. However, alumina and zirconia showed lower C5a concentrations and less protein adsorption than the reference materials. Our results revealed that oxide ceramic materials alone cannot be used for implants in direct blood contact without modification of the ceramic surface, for example, by made-to-measure inert nanocoatings.     

Two-stage revision surgery for infected total knee replacements: reasonable function and high success rate with the use of primary knee replacement implants as temporary spacers

Two-stage revision surgery for infected total knee replacements remains the gold standard treatment. Articulating spacers are preferred to static spacers for improved functional outcome. Articulating spacers made of cement can be prone to fracture, may not be suitable for full weight bearing, create abrasion debris and necessitate second-stage revision surgery. An alternative is the use of primary knee replacement implants as temporary spacers. With this technique, implants are loosely cemented into place at time of revision, allow the patient reasonable mobility and an ability to fully weight bear and can obviate the need for second-stage surgery. A retrospective review of all patients undergoing revision for infection over two years was conducted. Patients were clinically assigned to single- or two-stage revision. Patients who had a temporary knee replacement, that is, a primary knee replacement used as an articulating spacer, were identified and contacted to complete an Oxford Knee Score. Time to second stage and recurrence was identified from the notes 23 patients received temporary knee replacements. Of these, one patient died, 13 proceeded to a second-stage revision and nine remain in situ. Median time to second-stage revision was 19 weeks [range 11–27]. No patients had re-infection. Median follow-up for ongoing temporary knee replacements was 43 weeks [range 24–90]. Four temporary implants had survived for longer than 1 year. Median Oxford Knee Score was 26 [23–32] and satisfaction score was 8 out of 10 [8–8]. These early results show that knee replacement implants used as spacers provide a good alternative to cement-based articulating spacers with low re-infection rates. Their additional cost when compared with cement spacers is offset by the fact that many patients achieve adequate function and frail patients can avoid a revision procedure. Level of evidence Case series, Level IV.     

The PUVA-induced pigmented macule: A lentiginous proliferation of large,sometimes cytologically atypical,melanocytes

Eleven PUVA-induced pigmented macules (PM) obtained from seven psoriatic adults 4 to 6 years after starting PUVA therapy were compared to eight sun-induced pigmented macules (SM) and five specimens of light-protected skin (LPS) from twelve nonpsoriatic control subjects who had not received ultraviolet radiation therapy. Unlike SM, many PM were darkly or irregularly pigmented. In a blind histologic assessment using routine and l-dihydroxyphenylalanine (dopa)-incubated tissue sections, both PM and SM were lentigines. Three of eleven PM had slight melanocytic atypism, compared to none of eight SM. When compared to SM and LPS, PM had a significantly increased proportion of hypertrophic melanocytes. These observations demonstrate that chronic PUVA induces pigmented macules characterized by a lentiginous proliferation of large melanocytes which, in some cases, may be slightly atypical. PUVA-treated individuals require continual monitoring for atypical melanocytic lesions.     

The ��Golden Keys�� to health �C a healthy lifestyle intervention with randomized individual mentorship for overweight and obesity in adolescents

OBJECTIVE:

To conduct a pilot study designed to measure the impact of a healthy lifestyle intervention with or without individualized mentorship on adiposity, metabolic profile, nutrition and physical activity in overweight teens.

METHODS:

A total of 38 overweight adolescents (body mass index above the 85th percentile) 12 to 16 years of age, who were enrolled in a healthy lifestyle intervention program for six months, were randomly assigned to a nonmentored or individualized mentored intervention.

RESULTS:

For the entire cohort (final n=32), there was a nonstatistically significant reduction in mean (± SD) body mass index z score (2.08±0.38 to 2.01±0.47, P=0.07) and waist circumference (98±10 cm to 96±11 cm, P=0.08), and significant improvements in high-density lipoprotein level (1.08±0.24 mmol/L to 1.20±0.26 mmol/L, P<0.001), and low-density lipoprotein/high-density lipoprotein ratio (2.55±0.84 to 2.26±0.87, P<0.001) from baseline to the end of the intervention. Subjects consumed fewer high-calorie foods (3.9±1.9 to 3.0±1.5 servings/day, P=0.01) and snacks (9.7±5.5 to 6.8±4.0 servings/day, P=0.02), made fewer fast food restaurant visits (1.4±1.3 to 0.8±0.9 visits/week, P=0.02), and had less screen time (8.3±3.8 to 6.9±3.6 h/day, P=0.01). In addition, mentorship was found to be a feasible approach to supporting weight management in obese teens. Our study was underpowered to determine treatment effect, but promising modifications to lifestyle were observed despite the absence of statistically significant improvements in outcomes.

CONCLUSIONS:

The healthy lifestyle intervention improved subjects’ lifestyles and lipid profiles, and the addition of mentorship in this context is feasible. A larger study with a longer intervention time is required to determine whether behavioural changes are associated with clinical improvement and to determine the role of mentorship in promoting lifestyle change.     

Reactive angioendotheliomatosis with underlying hepatopathy and hypertensive portal gastropathy

A 64-year-old Caucasian man, with a long history of alcohol abuse complicated by hepatic cirrhosis and hypertensive portal gastropathy, presented with slightly painful progressive right forearm swelling. His only medication was spironolactone. He had no known allergies, no history of abnormal bleeding, and an otherwise noncontributory family and social history. A portal hepatic shunt had been inserted 9 months prior to presentation. Physical examination revealed a warm, indurated right forearm with purple–red macules extending circumferentially from the antecubital crease to the proximal wrist crease (Fig. 1). The right mid-forearm circumference was 2.5 cm greater than that on the left. The surface was irregularly studded with round, violaceous, nonblanching papules of 2–4 mm in diameter. No thrill or audible bruit was present. All pulses were intact and symmetric. He also had hepatomegaly, bilateral gynecomastia, palmar erythema, and numerous spider telangiectasias on the chest and abdomen. Ultrasonography of the area showed no clot; the swelling was entirely due to a fivefold expansion of the skin and subcutis. Two 4-mm punch biopsy specimens were obtained, one from a macule and one from a papule. Both specimens exhibited similar morphologic appearances. The superficial and mid-dermal plexus was filled with discrete lobular proliferations of endothelial-lined vascular spaces (Fig. 2). The endothelial cells were relatively uniform and large; their nuclei contained finely dispersed chromatin and inconspicuous nucleoli. Few mitotic figures were identified. There was no significant erythrocyte extravasation. Other areas assumed an epithelioid morphology, distinguished by large, plump endothelial cells that protruded into irregularly sized lumina. In these areas, an additional population of large cells had scattered cytoplasmic periodic acid–Schiff (PAS)-positive hyaline globules. These cells either surrounded the endothelial cells or merged imperceptibly with irregular vascular spaces containing delicate cytoplasmic projections. This proliferation was not confined to a strictly intravascular position, as demonstrated by extension outside the vascular basement membrane zone with PAS and reticulin stains. There were abundant mitotic figures (Fig. 3). Occasional lumina had fibrin thrombi. A scant infiltrate of mature, small lymphocytes surrounded the affected vascular spaces. The proliferating endothelial cells, as well as most of the stromal cells, were reactive with Ulex europaeus antigen-1 and antibodies directed against Factor VIII-related antigen, CD31, and CD34, and failed to express leukocyte common antigen (LCA), cytokeratin, or muscle specific (MSA) or smooth muscle specific (SMA) actin. The pericytic cuffs around affected vascular spaces were reactive for MSA and SMA, but negative for the above endothelial-associated antigens. Because of the lesion’s vascular nature, the patient was treated with a 585 nm flashlamp-pumped pulsed dye laser (Candela Laser, Wayland, MA). Two adjacent circular areas, each measuring 5 cm in diameter, were treated with a spot size of 5.0 mm at a fluence of 9 J/cm². One area received nonoverlapping pulses, while the second received pulses overlapping by 50%. A moderate degree of lightening was seen by 4 weeks and, according to his family members, dramatic improvement was seen in both areas by 8 weeks. Unfortunately, the patient expired due to bleeding esophageal varices, and no additional treatment or follow-up was possible.     

New insights into how the intestine can regulate lipid homeostasis and impact vascular disease: frontiers for new pharmaceutical therapies to lower cardiovascular disease risk

In recent years, evidence has emerged that the intestine is a significant regulator of systemic cholesterol homeostasis and can contribute to raised plasma cholesterol concentration. In this review we provide a context for the role the intestine may have in cardiovascular disease during conditions of chronic disease (insulin resistance, obesity). In particular, we highlight the physiological role of the intestine in lipid absorption, identify novel elements in enterocyte molecular biology, review the concept that chylomicrons and their remnants contribute to atherogenesis during chronic disease, and address new principles of chylomicron overproduction during conditions of insulin resistance including the associated hormonal control of the intestine during these conditions. Finally, we raise the issue of a growing need for novel lipid-lowering pharmaceutical therapies that target intestinal lipid metabolism.