How should procalcitonin and C-reactive protein levels be interpreted in haemodialysis patients?

BACKGROUND: Procalcitonin (PCT) and C-reactive protein (CRP) are used most widely in the diagnosis/treatment of bacterial infections. These are not infection-specific and may also show increases in other inflammation-causing cases. AIM: To establish a new cut-off value for PCT and CRP to eliminate confusion in the diagnosis and treatment of bacterial infections in haemodialysis (HD) patients. METHODS: A total of 1110 patients, 802 with undocumented infection and 308 with documented infection, was included in the study. RESULTS: A total of 802 patients with undocumented infection had a mean CRP value of 12.2 ± 9.6 mg/dL and a mean PCT value of 0.51 ± 0.96 ng/mL and the 308 patients with documented infection had a mean CRP value of 125.9 ± 83.3 mg/dL and a mean PCT value of 13.9 ± 26.9 ng/mL at the time of admittance. In HD patients, the cut-off values for CRP was determined as 19.15 mg/dL and for PCT as 0.685 ng/mL in the presence of infection. The use of these two parameters in combination (CRP ≥19.15 mg/dL and PCT ≥ 0.685 ng/mL) was found to have 95% positive predictive value (PPV) and 93% negative predictive value (NPV) for the diagnosis of infectious diseases in HD patients. When CRP ≥100 mg/dL and PCT ≥5 ng/mL, this was found to have 100% PPV and 94% NPV for the diagnosis of sepsis in HD patients. CONCLUSION: We specified PCT and CRP cut-off values with high PPV and NPV for revealing the presence of bacterial infection and sepsis in HD patients.

Effect of nepafenac eye drops on pain associated with pterygium surgery.

OBJECTIVE: To assess the effects of nepafenac ophthalmic suspension 0.1% for control of pain in patients undergoing pterygium surgery. METHODS: This randomized, double-masked placebo-controlled study included 62 adults undergoing pterygium surgery. Patients were randomly assigned to receive nepafenac ophthalmic suspension 0.1% or balanced salt solution placebo. They were asked to assess the level of pain using an 11-point numeric rating scale at 6, 12, 24, 48, and 72 hr after surgery. Patients also were evaluated daily for the progression of corneal epithelial healing until complete closure was observed. RESULTS: Except at 72 hr after surgery, the patients reported significantly less pain in eyes receiving nepafenac than in eyes receiving placebo. There was no statistical difference between the two groups in corneal epithelial healing. CONCLUSIONS: Treatment with nepafenac ophthalmic suspension 0.1% significantly reduced postoperative pain compared with placebo after pterygium surgery.

The effect of rebreathing and hyperventilation on retinal and choroidal vessels measured by spectral domain optical coherence tomography.

OBJECTIVE: The purpose of this study was to examine the vasoreactivity in retina and choroid of the healthy eyes in response to experimentally altered partial arterial pressure of carbon dioxide (PaCO(2)) using a non-invasive technique, spectral domain optical coherence tomography (SD-OCT). MATERIALS AND METHODS: The study included non-smoking participants between 18 and 35 years of age, having visual acuity of 20/20 and with no systemic and ocular diseases. At baseline, the participants breathed room air (normocapnia). Hypocapnia was created with the help of hyperventilation; for this, the participants were instructed to draw deep and quick breaths, resulting one breathing cycle per 2 s. To create hypercapnia subjects rebreathed from a 5 l bag at least 3 min. Choroidal thickness and retinal artery diameter were measured at baseline, and hyperventilation and rebreathing conditions by SD-OCT. RESULTS: Twenty eyes of 20 healthy subjects were included in this study. Their mean age was 24.90 ± 5.32 years. Hyperventilation caused a significant reduction in choroidal thickness, compared with baseline, at all points; whereas rebreathing caused no significant change at all points. The mean diameters of the arteries were 151.80 ± 7.88 µm, with a significant decline to 148.90 ± 7.25 µm at hyperventilation condition and a significant increase to 153.50 ± 7.88 µm at rebreathing condition (p = 0.018, p = 0.043, respectively). CONCLUSION: This study demonstrated that, SD-OCT was a useful tool in measuring the ocular vascular response under hypercapnia and hypocapnia conditions. These findings may be helpful for further understanding the physiological nature of ocular blood flow and this preliminary study provides a basis for future studies.