Hepatitis C prevalence in injecting drug users in Europe, 1990-2007: impact of study recruitment setting.

Monitoring injecting drug users' (IDUs) health is challenging because IDUs form a difficult to reach population. We examined the impact of recruitment setting on hepatitis C prevalence. Individual datasets from 12 studies were merged. Predictors of HCV positivity were sought through a multilevel analysis using a mixed-effects logistic model, with study identifier as random intercept. HCV prevalence ranged from 21% to 86% across the studies. Overall, HCV prevalence was higher in IDUs recruited in drug treatment centres compared to those recruited in low-threshold settings (74% and 42%, respectively, P < 0·001). Recruitment setting remained significantly associated with HCV prevalence after adjustment for duration of injecting and recent injection (adjusted odds ratio 0·7, 95% confidence interval 0·6-0·8, P = 0·05). Recruitment setting may have an impact on HCV prevalence estimates of IDUs in Europe. Assessing the impact of mixed recruitment strategies, including respondent-driven sampling, on HCV prevalence estimates, would be valuable.

Misleading results from immunoassays of serum free thyroxine in the presence of rheumatoid factor.

A novel interference with measurements of serum free thyroxine (FT4) caused by rheumatoid factor (RhF) is described. We found misleading, sometimes gross, increases of FT4 results in 5 clinically euthyroid elderly female patients with high RhF concentrations. All 5 patients had high FT4 on Abbott AxSYM or IMx analyzers. "NETRIA" immunoassays gave misleading results in 4 of the 5 patients; Amerlex-MAB in 2 of 4 patients; AutoDELFIA in 2 of the 5; and Corning ACS-180 and Bayer Diagnostics Immuno 1 in 1 of the 5. BM-ES700 system results for FT4 in these women remained within the reference range. Results for serum T4, thyroid-stimulating hormone, free triiodothyronine, thyroid-hormone-binding globulin, and FT4 measured by equilibrium dialysis were normal in all 5 patients. Drugs, albumin-binding variants, and anti-thyroid-hormone antibodies were excluded as interferences. Addition to normal serum of the RhF isolated from each of the 5 patients increased the apparent FT4 (Abbott AxSYM). Screening of 83 unselected patients demonstrated a highly significant positive correlation between FT4 (Abbott AxSYM) and RhF concentrations. Discrepant, apparently increased FT4 with a normal result for thyroid-stimulating hormone should lead to measurement of the patient's RhF concentration.

The Council on Clinical Optometric Care (CCOC): The American Optometric Association's Institutional-Practice Reviewer 1967-1993.

BACKGROUND: For 26 years the CCOC served professional optometry as its institutional-practice reviewer. METHODS: The council used nine standards for accrediting clinical institutions. RESULTS: The benefits of the accreditation process were many, with improved patient care as its cornerstone. CONCLUSION: During its 26 year existence, the Council on Clinical Optometric Care (CCOC) had a major influence on the quality of optometric care.

Swedish adolescents' knowledge of sexually transmitted diseases and their attitudes to the condom.

In an attempt to assess the risk of AIDS infection in teenagers in Sweden a survey of adolescent sexual behaviour was conducted in Uppsala. Two hundred and nine students in the first form of an upper secondary school completed a questionnaire at the beginning of a lesson on family life. Half the female and 45% of the male students reported having had sexual intercourse. Forty per cent had not used contraception at their first intercourse and 23% reported no use of contraceptive at their most recent intercourse. The students considered that they had only a low risk of contracting a sexually transmitted disease. The use of condoms was relatively low and this has implications for the students' potential to contract a sexually transmitted disease.

PIP: In an attempt to assess the risk of AIDS infection in teens in Sweden, a survey of adolescent sexual behavior was conducted in Uppsala. 209 students in the 1st form of an upper secondary school completed a questionnaire at the beginning of a lesson on family life. 1/2 of the female and 45% of the male students reported having had sexual intercourse. 40% had not used contraception at their 1st intercourse and 23% reported they had not used contraception at their most recent intercourse. The students considered that they had only low risk of contracting a sexually transmitted disease (STD). Condom use was relatively low and this had implications for the students' potential to contact an STD.

Reliability in perimetry.

As perimetric instrumentation becomes more sophisticated, patient reliability emerges as an important limiting factor in testing. Modern instrumentation for threshold and suprathreshold perimetry incorporate up to five separate indicators of patient reliability. For these perimetric methods, patient reliability is enhanced with specific techniques such as refractive correction, control of pupil size, and actively monitoring patient responses. With the manual (Goldmann) perimeter and the tangent screen, special statokinetic techniques help in both assessment and enhancement of patient reliability. In screening perimetry, reliability is assessed by analyzing the relative number, relative location, and repeatability of misses. Reliability in confrontation perimetry is both assessed and enhanced by using finger-counting and color-naming techniques. Review of the ophthalmic literature on perimetry shows how the various methods of patient reliability assessment and enhancement can be applied in the clinic.

A geriatric optometry residency.

Increasing demands for vision care for the elderly will result in increasing needs for specialty skills in optometry. Examples of such skills include management of degenerative eye disease, rehabilitation of impaired visual functions, assessment of psychosocial dysfunction, and interdisciplinary health team participation. This article shows how a geriatric optometry residency differs from the general optometric curriculum, and from other types of residencies, in preparing the optometrist to meet the special needs of the geriatric population.

The geriatric evaluation unit: optometry's role.

The geriatric evaluation unit (GEU), or geriatric assessment unit (GAU), is an increasingly popular component of the health care system. Interdisciplinary assessment and management by GEU teams is an effective way to lower the cost of long-term care for frail elderly hospital patients. Optometry can play a very important role on the GEU team because of the importance of vision assessment and care for the elderly.

The blue field entoptic test with normal patients.

One hundred normal patients were evaluated with the Blue Field Entoptoscope test. Of those one hundred patients, ninety-nine were able to describe the appearance of their own leukocytes. The methodology did not permit encouraging or coaching patients to see their leukocytes. Of the ninety-nine who could perceive their own leukocytes, nineteen 19.19%) were unable to perceive an approximately equal number in each of the four quadrants of the blue field of light which is divided by a reticle. These patients who did not see an equal number of leukocytes in all four quadrants were generally older than those who saw an equal number of leukocytes. The results indicate that if the Blue Field Entoptoscope is to be used in clinical practice or research, it is useful to standardize the instrument for the population studied. In particular, the instrument should be standardized for age.

Visual fields: simplified screening and recording procedures.

In some cases, visual field screening must be greatly simplified in order to obtain clinically useful information. This becomes possible when specific techniques are used for anomalies such as relative central scotoma, hemianopsia, and glaucomatous field defects. A working knowledge of visual pathway anatomy and function enables the optometrist to efficiently screen for these disorders by confrontation with red test objects, with pseudoisochromatic plates, and with the tangent screen. After the type of field defect has been determined by initial screening, recording its parameters with the tangent screen follows easily.

Calibration of the ERG photostimulus with standard photometer and photodiode.

A method for quantifying the ERG photostimulus is presented. The units of measure are reasonably straightforward and yet consistent with laws of photochemistry and psychophysics. Application of these laws facilitates measurement with readily available photometric instrumentation.

The electroretinogram: concepts and clinical applications.

This paper describes the clinical applications of the electroretinogram (ERG). Its purpose is to familiarize the practitioner with the capabilities, and limitations, of the ERG. This discussion includes ERG theory, test procedures, and interpretation of results.

Cone-rod dystrophy: a case report.

Cone-rod dystrophy is considered one of the rarer hereditary retinal degenerations. This disease can be easily mistaken for a number of other conditions because of its unusual characteristics. This paper discusses these characteristics and presents a case report to illustrate how the optometrist can effectively manage patients with this disease.

Angioid streaks: a case report.

A case of vision loss in a patient with angioid streaks and pseudoxanthoma elasticum is described. Discussion includes the natural course and clinical appearance of the disease, the role of trauma, and recommended optometric management.

Adverse reactions to topical ocular anesthetics.

The purpose of this article is to clarify some of the misunderstanding about adverse reactions to topical ocular anesthetics. Discussion will include: types of adverse reactions that are theoretically and practically possible; advice on handling the reactions that can occur; and precautions for minimizing their occurrence.