Skin cancers and precancerous lesions in Parkinson's disease patients.

Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.     

Ribavirin disposition in high-risk patients for acquired immunodeficiency syndrome

Ribavirin is a broad-spectrum antiviral drug that has in vitro activity against human immunodeficiency virus. To determine the kinetics of ribavirin, 17 symptom-free homosexual men with lymphadenopathy were studied. Single doses of ribavirin, 600, 1200, or 2400 mg, were given orally or intravenously. The plasma ribavirin concentration-time profiles were well fitted by a three-compartment open model. Ribavirin followed linear kinetics over the dose range studied. The mean 1-hour postinfusion concentrations after intravenous ribavirin, 600, 1200, and 2400 mg, were 8.0, 19.7, and 37.1 mumol/L, respectively. The mean +/- SD plasma beta-phase half-life, terminal-phase (gamma) half-life, and volume of distribution at steady state were 2.0 +/- 1.1 hours, 35.5 +/- 14.0 hours, and 647 +/- 258 L, respectively. The mean ribavirin renal clearance and total body clearance were 99 +/- 30 and 283 +/- 37 ml/min, respectively. After an oral dose of 600, 1200, and 2400 mg, the mean peak plasma ribavirin concentrations (which occurred 1.5 hours after administration) were 5.1, 9.9, and 12.6 mumol/L, respectively. The mean absorption half-life and bioavailability of ribavirin were 0.5 hour and 45%. Ribavirin had no plasma protein binding and the drug accumulated within red blood cells. In conclusion, ribavirin is incompletely absorbed from the gastrointestinal tract, its renal excretion accounts for approximately one third of the drug's elimination, and drug accumulation (greater than threefold) will result with repetitive dosing at the 6- to 8-hour dosing interval currently used.     

Predictive testing for Huntington's disease: I. Predictors of uptake in South Wales

In Wales, predictive testing for Huntington's disease (HD) has not been offered proactively to families and uptake of testing is low in comparison to other centres. Little is known of those not requesting testing, particularly those not in direct contact with the genetics service. This study examined differences between a cohort of 22 test applicants and a random group of 32 'non-requesters', drawn from the South Wales HD register. Respondents were interviewed by means of a semi-structured schedule in their own homes. The study groups differed significantly on a number of variables including: knowledge of the availability of testing; perceived attitudes of family members and significant others to testing; length of knowledge and perceived stressfulness of being at risk; and perceived ability to cope with an unfavourable result. Overall, knowledge of testing procedures was poor and at-risk individuals' understanding of genetic terminology was at odds with scientific distinctions. Discussion focuses on the organisational and psychological factors associated with lack of knowledge of the availability of testing and the interpretation of reported coping capacities.     

Paranoid states: classification and management

In terms of both nosology and treatment the paranoid states have long proved a thorny but irresistible enigma to psychiatrists. Recent evidence suggests that at least one of these conditions, paranoia, not only may be eminently treatable, but also merits serious consideration as a clinical entity distinct from other functional psychoses.