Permanent Spacers Are a Reliable Solution for Peri-prosthetic Shoulder Infection: A Systematic Review

HSS Journal ® - Peri-prosthetic shoulder infection (PSI), a highly disabling complication of shoulder arthroplasty, often requires additional surgery and prolonged antibiotic therapy. Of...     

Streptococcal infection as possible trigger for dense deposit disease (C3 glomerulopathy)

Dense deposit disease (DDD, formerly known as membranoproliferative glomerulonephritis (MPGN) type II) is a subtype of C3 glomerulopathy (C3G). Electron-dense deposits in the glomerular basement membrane characterize this glomerulonephritis. DDD typically presents with a nephritic syndrome that progresses to end-stage renal failure in 50 % of patients despite treatment. The pathogenic basis of DDD is uncontrolled activation of the alternative complement cascade although the potential triggering events that precipitate the development of complement dysregulation are typically unknown. There are isolated reports of an apparent association between streptococcal infection and DDD, as well as with MPGN types I and III. However, this association has not been deemed compelling, perhaps because so few cases have been reported or because of a current lack of evidence for a plausible hypothesis to connect a streptococcal infection with subsequent disease. In this report, we describe two patients with DDD who definitely had an antecedent streptococcal infection with the phenotype of acute post-streptococcal glomerulonephritis and whose initial kidney biopsy findings on light microscopy were indistinguishable from acute post-streptococcal glomerulonephritis. These patients had additional points of interest: recurrence of gross hematuria with recurrent streptococcal infections, slowly progressive course, persistently low serum C3 concentration, positive C3 nephritic factor, and positive risk alleles in the complement factor H (CFH) gene. Conclusion: We suggest that streptococcal infection may trigger DDD in individuals genetically predisposed by virtue of a disorder in complement regulation.     

Bicarbonate transport along the loop of Henle. II. Effects of acid-base, dietary, and neurohumoral determinants.

The loop of Henle contributes to renal acidification by reabsorbing about 15% of filtered bicarbonate. To study the effects on loop of Henle bicarbonate transport (JHCO3) of acid-base disturbances and of several factors known to modulate sodium transport, these in vivo microperfusion studies were carried out in rats during: (a) acute and chronic metabolic acidosis, (b) acute and chronic (hypokalemic) metabolic alkalosis, (c) a control sodium diet, (d) a high-sodium diet, (e) angiotensin II (AII) intravenous infusion, (f) simultaneously intravenous infusion of both AII and the AT1 receptor antagonist DuP 753, (g) acute ipsilateral mechanicochemical renal denervation. Acute and chronic metabolic acidosis increased JHCO3; acute metabolic alkalosis significantly reduced JHCO3, whereas chronic hypokalemic alkalosis did not alter JHCO3. Bicarbonate transport increased in animals on a high-sodium intake and following AII administration, and the latter was inhibited by the AII (AT1) receptor antagonist DuP 753; acute renal denervation lowered bicarbonate transport. These data indicate that bicarbonate reabsorption along the loop of Henle in vivo is closely linked to systemic acid-base status and to several factors known to modulate sodium transport.     

Relationship Styles and Mortality in Patients With Diabetes

OBJECTIVE

Prior research has shown that less social support is associated with increased mortality in individuals with chronic illnesses. We set out to determine whether lower propensity to seek support as indicated by relationship style, based on attachment theory, is associated with mortality in patients with diabetes.

RESEARCH DESIGN AND METHODS

A total of 3,535 nondepressed adult patients with type 1 and type 2 diabetes enrolled in a health maintenance organization in Washington State were surveyed at baseline and followed for 5 years. Relationship style was assessed at baseline. Patients with a greater propensity to seek support were classified as having an interactive relationship style and those less inclined to seek support as having an independent relationship style. We collected Washington State mortality data and used Cox proportional hazards models to estimate relative risk (RR) of death for relationship style groups.

RESULTS

The rate of death in the independent and interactive relationship style groups was 39 and 29 per 1,000 individuals, respectively. Unadjusted RR of death was 1.33 (95% CI 1.12–1.58), indicating an increased risk of death among individuals with an independent relationship style. After adjustment for demographic and clinical covariates, those with an independent relationship style still had a greater risk of death compared with those with an interactive relationship style (hazard ratio 1.20 [95% CI 1.01–1.43]).

CONCLUSIONS

In a large sample of adult patients with diabetes, a lower propensity to reach out to others is associated with higher mortality over 5 years. Further research is needed to examine possible mechanisms for this relationship and to develop appropriate interventions.The presence of a supportive social network positively affects health by increasing access to instrumental, informational, and emotional support (1). In patients with diabetes, a higher level of social support is associated with improved treatment adherence, better glycemic control, and greater diabetes knowledge (2). Conversely, lower social support has been associated with higher mortality in patients with various chronic conditions (3,4), including patients with diabetes (5).Clinicians treating patients with chronic conditions generally understand these associations and attempt to encourage patients to seek and receive greater support from patients'' family, friends, peers, and social agencies. Clinicians may also encourage greater collaboration in the patient-provider relationship. Although many patients are receptive to such suggestions and efforts, a significant proportion is less receptive or not receptive at all. For example, regardless of the ready availability of a social network, many patients do not benefit from their support at times of need. Among patients who do not collaborate well with others, many have long-term patterns of not doing so, suggesting the influence of stable characteristics. If there are measurable patient characteristics that predict an individual''s capacity to use supports over time, such information may be useful for shaping approaches and recommendations that providers make in clinical settings.Attachment theory provides a theoretical, evidence-based model for understanding the propensity and ability of individuals to reach out to others for support. This theory posits that all individuals develop a cognitive map based on prior experiences that determines one''s comfort and ability to interact with or reach out to others, particularly at times of distress (6). On the basis of empirical research in infants, children, and adults over the past 30 years, distinct relationship styles arising from these cognitive maps have been identified (7) and demonstrate high levels of stability and continuity between early childhood and adulthood (8). Two of the styles, “dismissing” and “fearful” attachment style, are characterized by difficulty reaching out for support or trusting others, and patients with these styles and characteristics have been described as having an independent relationship style (9). Among clinical populations with diabetes, 48% of patients are typically found to have an independent relationship style (10). The remainder have an interactive relationship style, comprising those with “secure” and “preoccupied” attachment styles. Patients with an interactive relationship style have greater comfort reaching out to others, although individuals with a preoccupied style are often characterized as being highly dependent on others (11).In a large sample of primary care patients with diabetes (9,12), an independent relationship style has been associated with more missed primary care visits, lower satisfaction with care, higher A1C levels, and decreased adherence to exercise, quitting smoking, foot care, diet, and oral hypoglycemic medications. Another study showed that having a relationship style characterized by difficulty trusting or reaching out to others is associated with decreased adherence to glucose monitoring and insulin injections among patients with diabetes (13).In a recent article, we demonstrated that patients with major depression in this epidemiological sample were more likely to die over a 5-year period (hazard ratio [HR] 1.53) (14). In the current study, we set out to determine whether relationship styles are associated with mortality in patients with diabetes. Because depression status is associated with poorer collaboration as measured by relationship style (15), we conducted our analyses in nondepressed patients. In the current study, we hypothesized that among nondepressed patients with diabetes, those with an independent relationship style would have higher mortality over a 5-year period than patients with an interactive relationship style.