Hyponatraemia in patients with community-acquired pneumonia; prevalence and aetiology, and natural history of SIAD.

OBJECTIVE: Hyponatraemia is common in community-acquired pneumonia (CAP) and is associated with increased mortality. The mechanism of hyponatraemia in CAP is not completely understood and treatment is therefore ill-defined. We aimed to define the causation of hyponatraemia in CAP. DESIGN: Prospective, single-centre, observational study of all patients with CAP and hyponatraemia (≤ 130 mmol/L) during a 9-month period. PATIENTS: The prevalence of each subtype of hyponatraemia, and the associated mortality, was determined in 143 admissions with CAP (Study 1). A sub-cohort of patients with SIAD (n = 10) was prospectively followed, to document the natural history of SIAD associated with CAP (Study 2). MEASUREMENTS: In Study 2, blood and urine were collected on day 1, 3, 5 and 7 following admission for measurement of plasma vasopressin, sodium, osmolality and urine osmolality. RESULTS: In study 1, 143/1723(8.3%) of CAP patients had hyponatraemia (≤130 mmol/L). About 66 had SIAD (46%), 60(42%) had hypovolaemic hyponatraemia (HON), 13(9%) had hypervolaemic hyponatraemia (HEN) and 4(3%) patients had hyponatraemia due to glucocorticoid hormone deficiency. Mortality was higher in the HEN than in the HON, SIAD or normonatraemic groups (P < 0.01). In Study 2, plasma sodium concentration normalized in 8/10 (80%) by day 7. Two patients with persistent hyponatraemia were discovered to have underlying bronchiectasis. CONCLUSIONS: Hyponatraemia in CAP is most commonly secondary to SIAD or hypovolaemia. HEN is less common, but has worse prognosis. Prospective observation demonstrates that in SIAD, plasma AVP and sodium concentrations normalize with antimicrobials; failure of reversal of suggests underlying lung disease, such as bronchiectasis.

Multiple Vertebral Compression Fractures Secondary to Pregnancy-induced Osteoporosis: A Case Report.

Introduction: Although rare in incidence, pregnancy-induced osteoporosis (PIO)-associated OVCFs represent a significant cause of morbidity for the young, peri-partum female population. Case Report: We present the case of a 27-year-old nulliparous lady who suffered seven osteoporosis vertebral compression fractures (OVCFs) with associated sagittal imbalance, the challenges posed to the attending physician or surgeon in treating this rare condition, as well as an in-depth discussion of previous literature reported on pregnancy-induced osteoporosis (PLIO) to date. Although rare in incidence, PLIO-associated OVCFs represent a significant cause of morbidity for the young, peripartum female. Conclusion: This case demonstrates how multiple PLIO-associated OVCFs may be managed successfully, with careful consideration of sagittal imbalance, using a combination of medical and non-operative orthopedic therapies at medium-term follow-up.

Increased SRF transcriptional activity in human and mouse skeletal muscle is a signature of insulin resistance.

Insulin resistance in skeletal muscle is a key phenotype associated with type 2 diabetes (T2D) for which the molecular mediators remain unclear. We therefore conducted an expression analysis of human muscle biopsies from patients with T2D; normoglycemic but insulin-resistant subjects with a parental family history (FH(+)) of T2D; and family history-negative control individuals (FH(­)). Actin cytoskeleton genes regulated by serum response factor (SRF) and its coactivator megakaryoblastic leukemia 1 (MKL1) had increased expression in T2D and FH(+) groups. Furthermore, striated muscle activator of Rho signaling (STARS), an activator of SRF, was upregulated in T2D and FH(+) and was inversely correlated with insulin sensitivity. Skeletal muscle from insulin-resistant mice recapitulated this gene expression pattern and showed reduced G-actin and increased nuclear localization of MKL1, each of which regulates SRF activity. Overexpression of MKL1 or reduction in G-actin decreased insulin-stimulated Akt phosphorylation, whereas reduction of STARS expression increased insulin signaling and glucose uptake. Pharmacological SRF inhibition by CCG-1423 reduced nuclear MKL1 and improved glucose uptake and tolerance in insulin-resistant mice in vivo. Thus, SRF pathway alterations are linked to insulin resistance, may contribute to T2D pathogenesis, and could represent therapeutic targets.

Use of salsalate to target inflammation in the treatment of insulin resistance and type 2 diabetes.

OBJECTIVES: Chronic subacute inflammation is implicated in the pathogenesis of insulin resistance and type 2 diabetes. Salicylates were shown years ago to lower glucose and more recently to inhibit NF-kappaB activity. Salsalate, a prodrug form of salicylate, has seen extensive clinical use and has a favorable safety profile. We studied the efficacy of salsalate in reducing glycemia and insulin resistance and potential mechanisms of action to validate NF-kappaB as a potential pharmacologic target in diabetes. METHODS AND RESULTS: In open label studies, both high (4.5 g/d) and standard (3.0 g/d) doses of salsalate reduced fasting and postchallenge glucose levels after 2 weeks of treatment. Salsalate increased glucose utilization during euglycemic hyperinsulinemic clamps, by approximately 50% and 15% at the high and standard doses, respectively, and insulin clearance was decreased. Dose-limiting tinnitus occurred only at the higher dose. In a third, double-masked, placebo-controlled trial, 1 month of salsalate at maximum tolerable dose (no tinnitus) improved fasting and postchallenge glucose levels. Circulating free fatty acids were reduced and adiponectin increased in all treated subjects. CONCLUSIONS: These data demonstrate that salsalate improves in vivo glucose and lipid homeostasis, and support targeting of inflammation and NF-kappaB as a therapeutic approach in type 2 diabetes.