Novel Colorimetric and Light Scatter Methods to Identify and Manage Peritoneal Dialysis-Associated Peritonitis at the Point-of-Care.

Introduction: Peritoneal dialysis (PD)-related peritonitis (PDRP) is a common cause of transfer to hemodialysis, patient morbidity, and is a risk factor for mortality. Associated patient anxiety can deter selection of PD for renal replacement therapy. Diagnosis relies on hospital laboratory tests; however, this might be achieved earlier if such information was available at the point-of-care (POC), thereby significantly improving outcomes. The presence of culturable microbes and the concentration of leukocytes in effluent both aid peritonitis diagnosis, as specified in the International Society for Peritoneal Dialysis (ISPD) diagnostic guidelines. Here, we report the development of 2 new methods providing such information in simple POC tests. Methods: One approach uses a tetrazolium-based chemical reporting system, primarily focused on detecting bacterial contamination and associated vancomycin-sensitivity. The second approach uses a novel forward light-scatter device (QuickCheck) to provide an instant quantitative cell count directly from PD patient effluent. Results: The tetrazolium approach detected and correctly distinguished laboratory isolates, taking 10 hours to provide non-quantitative results. We compared the technical performance of the light scatter leukocyte counting approach with spectrophotometry, hemocytometer counting and flow cytometry (Sysmex) using patient effluent samples. QuickCheck had high accuracy (94%) and was the most precise (coefficient of variation <4%), showing minimal bias, overall performing similarly to flow cytometry. Conclusion: These complementary new approaches provide a simple means to obtain information to assist diagnosis at the POC. The first provides antibiotic sensitivity following 10 hours incubation, whereas the second optical approach (QuickCheck), provides instant accurate total leukocyte count.

Acute peritoneal dialysis in a Jehovah's Witness post laparotomy.

A 56-year-old man who was a Jehovah's Witness with an advanced directive against autologous procedures developed acute kidney injury needing renal replacement therapy while he was intubated and ventilated on the intensive care unit. He was being treated for hyperosmolar hyperglycaemic state. He also had a healing laparotomy wound, having undergone a splenectomy less than a month ago following a road traffic accident. His hyperkalaemia and metabolic acidosis were refractory to medical treatment. As he became oligoanuric, decision was taken to carry out acute peritoneal dialysis (PD) by inserting a Tenckhoff catheter in his abdomen using peritoneoscopic technique. The patient was started on automated PD without any complications. His urine output gradually improved, and his renal function eventually recovered. On discharge from hospital, his renal function was within normal range, and he had no abdominal complications from the acute PD.

Cathasept Line Lock and Microbial Colonization of Tunneled Hemodialysis Catheters: A Multicenter Randomized Controlled Trial.

BACKGROUND: Catheter-related bloodstream infections (CRBSIs) cause morbidity and mortality in hemodialysis (HD) patients. Cathasept (tetra-sodium EDTA) solution has antimicrobial and anticoagulant activities. STUDY DESIGN: Multicenter prospective randomized controlled study. SETTING & PARTICIPANTS: 117 maintenance HD patients with confirmed uncolonized tunneled HD catheters from 4 HD centers. INTERVENTION: Patients were randomly assigned to receive Cathasept 4% locks (Cathasept group) or stayed with heparin 5,000 U/mL locks (heparin group), filled thrice weekly according to catheter lumen volume until the catheter was removed or for a maximum of 8 months. OUTCOMES: Primary outcome was clinically significant microbial colonization of the catheter, defined as a through-catheter quantitative blood culture yielding ≥ 1,000 colony-forming units/mL of bacteria or yeast. Secondary outcomes included CRBSI rate, catheter patency, and biomarkers of inflammation and anemia. MEASUREMENTS: Weekly through-catheter quantitative blood culture, high-sensitivity C-reactive protein fortnightly, and full blood count and ferritin monthly. RESULTS: Incidence rates of catheter colonization were 0.14/1,000 catheter-days in the Cathasept group and 1.08/1,000 catheter-days in the heparin group (incidence rate ratio [IRR], 0.13; 95% CI, 0.003-0.94; P=0.02). CRBSI rates were 0.28/1,000 catheter-days in the Cathasept group and 0.68/1,000 catheter days in the heparin group (IRR, 0.40; 95% CI, 0.08-2.09; P=0.3). The proportion of dialysis sessions with achieved prescribed blood flow rate was significantly lower in the Cathasept group (66.8% vs 75.3%; P<0.001), with more patients requiring thrombolytic locks or infusions to maintain catheter patency (22 vs 9; P=0.01). Mean high-sensitivity C-reactive protein level was 11.6±5.3 (SE) mg/L lower for patients in the heparin group (P=0.03). Anemia marker levels were similar in both groups. LIMITATIONS: Study was underpowered to assess effect on CRBSI, terminated early due to slow recruitment, and not double blinded. CONCLUSIONS: Cathasept significantly reduced tunneled hemodialysis catheter colonization, but the reduction in CRBSIs was not statistically significant, and it was associated with more thrombotic complications. Its safety profile was comparable to heparin lock solution.

Spontaneous perirenal haemorrhage in polyarteritis nodosa.

Patients presenting with flank pain are likely to have urological pathology but when features of hypotension are present high index of suspicion is needed to reach the cause such as perirenal haemorrhage. Spontaneous perirenal haemorrhage (SPH) is an uncommon presentation of vasculitis, autoimmune disease or malignancy. It is common in males in the age group between 30 and 60 years. Polyarteritis nodosa (PAN) is one of the commonest vascular diseases associated with SPH. Angiography adds valuable information to the diagnosis and management and can prevent unnecessary nephrectomy. We report a case of SPH that was successfully managed with angioembolization.

Spontaneous cholesterol embolisation causing acute renal failure.

We present a case of true spontaneous cholesterol embolisation causing acute renal failure. There was no history of vascular procedural interventions or thrombolytic therapy prior to her presentation, but the patient did have a history of difficult hypercholesterolemia and atherosclerosis. This case highlights the importance of remembering cholesterol embolisation as a potential cause of acute renal failure despite no apparent precipitant, especially with the presence of unexplained eosinophilia.

The relationship between serum albumin and hydration status in hemodialysis patients.

OBJECTIVE: A decreased serum albumin level predicts poor survival in end-stage renal failure. Hypoalbuminemia is multifactorial and related to poor nutrition, inflammation, and comorbid disease. Overhydration is also common in renal replacement therapy patients, and hemodilution may also contribute to a low serum albumin level. DESIGN: Crosssectional observational study. SETTING: Outpatient hemodialysis unit of a district general hospital. SUBJECTS: We investigated the relationship of serum albumin to C-reactive protein (CRP) and hydration state in 49 unselected hemodialysis patients (28 men). METHODS: Patients were assessed predialysis and postdialysis at their clinical dry weight. Extracellular fluid volume (Vecf) and total body water (Vtbw) were estimated by whole-body bioelectric impedance. Vecf was expressed as a percentage of Vtbw (Vecf%Vtbw). Predialysis CRP, predialysis and postdialysis serum albumin, and body weight were measured. Normalized protein catabolic rate (nPCR) and KT/V urea were calculated. RESULTS: Predialysis and postdialysis serum albumin levels were 36.9 g/L (95% CI, 35.7 and 38.1) and 41.4 g/L (95% CI, 39.7 and 43.3), respectively (P <.0001). Mean weight change was 2.0 +/- 1.2 kg. Predialysis and postdialysis serum albumin levels were negatively correlated with CRP (before: r = -0.393, P <.005; after: r = -0.445, P =.001) and positively with nPCR (before: r = 0.336, P =.018; after: r = 0.353, P =.013). Predialysis serum albumin level correlated with predialysis Vecf%Vtbw (r = -0.384, P =.006) and postdialysis serum albumin level with postdialysis Vecf%Vtbw (r = -0.654, P <.0001). In multivariate analysis, predialysis albumin was dependent on nPCR (P =.04), CRP (P <.0001), and predialysis Vecf%Vtbw (P =.002), and postdialysis albumin was dependent on nPCR (P =.01), CRP (P =.002), and postdialysis Vecf%Vtbw (both P <.0001). The increase in albumin was strongly correlated with both change in actual weight (r = -0.651, P <.0001) and change in Vecf%Vtbw (r = -0.684, P <.0001). CONCLUSION: In unselected hemodialysis patients, serum albumin level is dependent on nPCR, CRP, and extracellular fluid volume. This relationship persists after dialysis, suggesting that many patients remain fluid overloaded at their postdialysis dry weight.