Hepatitis C virus (HCV) infection is common among intravenous drug users, and because of the long latent period, HCV liver disease is set to increase.

We sought to examine practice guidelines regarding treatment of HCV in drug users and to review the evidence for current practices.

A structured search of the Pubmed database, websites of the National Institute for Clinical Excellence and national and international expert groups and opinion of independent experts in the field.

All those infected with HCV need to be assessed to ascertain whether they have active ongoing viral replication and the extent of liver damage. HCV-infected individuals should be educated about the modes of transmission and means of reducing the risk of infecting others. They should also be advised to avoid cofactors (especially alcohol) that accelerate the progression of liver disease. Specific treatment with antivirals can cause viral clearance and prevent the progression of liver disease. Therapy is effective in those on opiate-replacement treatments and also in motivated individuals who continue to use intravenous drugs. The decision whether to treat drug users should be made jointly by specialists in the management of viral hepatitis and addiction on a case-by-case basis. Current combination drug regimens are expensive but are claimed to be cost-effective, and are certainly much less costly than managing end-stage liver disease. In addition to satisfactory sustained viral response rates, other benefits such as a beneficial effect on drug habit, self-esteem and rehabilitation have been reported. Encouraging suitable drug users to take-up and comply with treatment seems to be more easily achieved in supportive drug dependency unit settings (rather than the more formal surroundings of a hospital clinic).

New evidence is emerging regarding abnormalities of hypothalamic-pituitary-adrenal (HPA) axis function in subtypes of affective disorders. Adverse effects of HPA axis dysregulation may include dysfunction of monoaminergic transmitter systems, cognitive impairment and peripheral effects. Newer treatments specifically targeting the HPA axis are being developed.

To review these developments focusing particularly on the glucocorticoid receptor (GR) antagonist mifepristone.

A selective review of the literature.

The function of GRs is increasingly being defined. The role of corticotrophin-releasing hormone (CRH) and dehydroepiandrosterone (DHEA) in the brain is also increasingly understood. HPA axis function is particularly likely to be abnormal in psychotic depression and bipolar disorder, and it is in these conditions that trials of the GR antagonist mifepristone are being focused. CRH antagonists and DHEA are also being investigated as potential treatments.

Initial studies of mifepristone and other HPA-axis-targeting agents in psychotic depression and bipolar disorder are encouraging and confirmatory studies are awaited.

Double depression, the combination of major depression and dysthymia, is associated with poor health-related quality of life (HRQoL) and increased health service utilization.

To determine the prevalence of double depression, its associated morbidity and use of health services and antidepressants.

A random and representative sample of the South Australian general population was interviewed. The mood module of the Primary Care Evaluation of Mental Disorders (PRIME-MD), the Short-Form Health Status Questionnaire (SF-36) and Assessment of Quality of Life (AQoL) instruments were administered, and data relating to health service utilization, antidepressant use and role functioning were collected.

Double depression was present in 3.3% of the population. The use of health services was significantly higher in this group than those with no depression, or dysthymia or major depression alone. Only 15.2% had attended a community health service, 18.2% had seen a psychiatrist, 10.1% a psychologist, 16.2% a social worker and 9.1% any other counsellor in the last month. While 41.4% were currently taking an antidepressant, the average doses of the two most commonly prescribed antidepressants were below the maximum recommended doses, and the use of antidepressant augmentation strategies was also minimal.

While double depression is associated with increased morbidity and use of health services, the optimum use of both pharmacological and nonpharmacological treatments is clearly lacking in this community sample.

Individuals with traumatic brain injury (TBI) often suffer from a number of enduring cognitive impairments such as in attention, memory, speed of processing information and dual-task performance.

The aim of this study was to assess the patterns of regional brain activation in response to the Tower of London (ToL) task in a group of patients suffering from chronic TBI using functional magnetic resonance imaging (fMRI).

fMRI was performed during performance of the ToL planning task in 10 patients suffering from severe TBI and in 10 age- and sex-matched controls using a 3 T magnetic resonance scanner.

Performance data showed no difference in response accuracy between the TBI group and the healthy control group. Statistical parametric brain maps showed that the TBI group activates larger and additional areas of the cerebral cortex than the healthy control group both for tasks and for a subtraction contrast between the tasks.

The results of this study are interpreted as a cortical reorganization inside the executive system of vigilance and working memory in patients with TBI. Both parietal and frontal areas are recruited to compensate for damaged brain tissue.

Previous studies on substance-dependent populations have shown that age of first use and duration of use are associated with alterations in regional brain volumes. However, it is not clear whether such alterations are factors that predispose young people to use, and so are also present in recreational users, or are a consequence of chronic exposure to substances and/or comorbid psychopathology.

To investigate relationships between key brain structures and parameters of alcohol and cannabis use, in otherwise healthy male recreational users.

High-resolution magnetic resonance imaging was used to measure hippocampal, amygdala, whole-brain and intracranial cavity (ICC) volumes in 22 young men with a history of both alcohol and cannabis use.

Linear regression analyses with hippocampal, amygdala and whole-brain volumes as the dependent variables and age and ICC as covariates were performed. Findings showed that use of cannabis and alcohol at an earlier age were independently predictive of larger amygdala volumes, whereas longer duration of cannabis use was predictive of smaller hippocampal volumes.

Our findings offer preliminary support for a relationship between patterns of substance use and regional brain volumes in recreational users. It is speculative, but possible that this relationship is an evidence of a neurobiological vulnerability to drug-taking behaviour.

Peduncular hallucinosis is a rare stroke-related phenomenon that may occur in cases of ischemic lesions localized in the cerebral peduncles, the pons, the upper midbrain or the thalamus and is mostly characterized by transient visual hallucinations.

We report the case of an insufficiently treated hypertensive patient who presented with constantly elevated blood pressure values and persistent visual hallucinations, which ceased a few hours later after medically achieved blood pressure normalization. Magnetic resonance imaging (MRI) revealed a symmetric paramedian ischemic lesion of the upper pons, which seems to be the cause of this case of peduncular hallucinosis.

Although uncommon, this entity needs to be differential diagnostically considered in cases of transient visual hallucinations in persons with known vascular risk profile. MRI can be a useful diagnostic tool.