Efficiency of prostate-specific antigen and digital rectal examination in screening, using 4.0 ng/ml and age-specific reference range as a cutoff for abnormal values

BACKGROUND: The purpose of this study was to examine the diagnostic efficiency of prostate-specific antigen (PSA) and digital rectal examination (DRE) testing when using either 4.0 ng/ml or an age-specific reference range (ASRR) as an abnormal cutoff PSA value. METHODS: Between 1992-1995, 116,073 men, aged 40-79 years, were screened during Prostate Cancer Awareness Week. When using a 4.0-ng/ml cutoff PSA value, 22,014 had either an abnormal PSA, an abnormal DRE, or both. When using an ASRR cutoff PSA value, 17,561 had either an abnormal PSA, an abnormal DRE, or both. The positive predictive value (PPV), sensitivity, and specificity of PSA, DRE, and combined PSA and DRE tests were evaluated. RESULTS: When using a 4.0-ng/ml cutoff PSA value, the PPVs of abnormal PSA alone, abnormal DRE alone, and combined abnormal PSA and DRE tests were 27.7%, 17.7%, and 56.0%, respectively. Sensitivities were 34.9%, 27.1%, and 38.0%, respectively. Specificities were 63.1%, 49.0%, and 87.9%, respectively. When using an ASRR cutoff PSA value, the PPVs of each category were 31.8%, 20.8%, and 63.7%, respectively. Sensitivities were 27.1%, 41.0%, and 31.8%, respectively. Specificities were 75.0%, 32.8%, and 92.2%, respectively. The PPVs of the PSA test were higher than those of the DRE. The PPVs of combined tests were highest when using either a 4.0-ng/ml cutoff PSA value or an ASRR cutoff PSA value (all P < 0.001). When using an ASRR, the PPVs of PSA, DRE, and combined tests were higher than those when using a 4.0-ng/ml without statistical significance (all P > 0.05). Sensitivity of PSA when using an ASRR was lower than when using 4.0 ng/ml. CONCLUSIONS: Significantly higher PPVs indicated that utilizing both a PSA test and a DRE is most effective in screening for the early detection of prostate cancer. Although higher PPVs when using an ASRR cutoff PSA value suggested fewer unnecessary biopsies, lower sensitivities resulted in fewer cancers detected. Thus, we recommend that the combination of a PSA test with a cutoff value of 4.0 ng/ml and a DRE should continue to be utilized in the screening programs.     

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 (PaCO₂) 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.     

Decreased Activity and Genetic Polymorphisms of CYP2C19 in Behçet's Disease

Behçet's disease (BD) is a systemic autoimmune disorder. Cytochrome P450 enzymes (CYPs) are responsible for various drug metabolism reactions as well as those of endogenous substances which may be associated with autoimmune disease susceptibility. Recently, we reported that in patients with BD, CYP2C9 seems to be down‐regulated due to inflammation. In the same Turkish patients with BD, we investigated whether also CYP2C19 activity is decreased. Lansoprazole (30 mg) was given as a probe drug to evaluate CYP2C19 activity in 59 patients with BD and 27 healthy control volunteers. An HPLC method was used to determine plasma lansoprazole and its metabolite, 5‐hydroxy lansoprazole, concentrations. The genotyping for CYP2C19 *2, *3 and *17 polymorphisms was made using PCR‐RFLP. The median lansoprazole/5‐hydroxy lansoprazole metabolic ratio (MR) in patients with BD was 2.6‐fold higher as compared to the healthy control group (p = 0.001, 22.6 (1.3–26) and 8.8 (0.5–140) as median and range, respectively). The CYP2C19*17*17 genotype frequency was found to be significantly less in the BD group as compared to the healthy controls (1.7% versus 14.8% in controls, p = 0.01). Additionally, colchicine treatment did not affect the CYP2C19 enzyme activity in six patients (p = 0.43). In conclusion, the patients with BD had lower CYP2C19 enzyme activity and lower frequency of the CYP2C19*17 allele as compared to those of the healthy controls. Further studies are warranted on the mechanisms underlying this relation. This study should also be applied to other autoimmune diseases similarly characterized by local or systemic inflammation.     

The comparison of in the vitro effect of imipenem or meropenem combined with ciprofloxacin or levofloxacin against multidrug-resistant Pseudomonas aeruginosa strains

This study evaluated the in vitro effects of the combination of a carbapenem (imipenem or meropenem) with a quinolone (ciprofloxacin or levofloxacin) using a microbroth dilution chequerboard technique and multidrug-resistant Pseudomonas aeruginosa strains. The ciprofloxacin and meropenem combination was only synergistic against 2 strains (6.2%) and ciprofloxacin and imipenem against 1 strain (3.1%). Levofloxacin and imipenem or meropenem were not synergistic for against any strain. None of the combinations showed an antagonistic effect.     

Bilateral narrow duplicated internal auditory canal

Internal auditory canal (IAC) anomalies are rare malformations that may include alterations of shape, size or orientation of the IAC. Bilateral duplication of IAC is a very rare malformation and only one case has been described in literature. We report a case of bilateral duplicated IAC together with other inner ear anomalies.