Hepatitis C virus (HCV) infection results in chronic liver disease in a substantial proportion of those infected. Most new cases of HCV infection in the UK are associated with intravenous drug use. It is important to identify these infections because of the implications for the future health of the individuals concerned and for the control of further spread of infection. However, as hepatitis C infection is characterised by a relatively long asymptomatic period of seronegative viraemia, a laboratory diagnostic protocol that does not test HCV seronegative samples for the presence of HCV RNA may wrongly designate HCV viraemic seronegative individuals as uninfected. Amongst 424 injecting drug users whose serum was sent to our diagnostic laboratory for "HCV screening" over a 14-month period, the prevalence of HCV seropositivity was 48.4%. We retrospectively identified seven individuals for whom there was evidence of recent acquisition of HCV infection. Three of these infections were identified using our routine diagnostic protocol: testing for the presence of HCV-specific antibody and performing HCV RNA testing only on seropositive and seroindeterminate specimens. However, four cases were only identified by HCV RNA testing of HCV seronegative serum. On the basis of these observations, we estimate the incidence of HCV infection amongst London injecting drug users as being 14.3 per 100 person-years. We advocate that all HCV seronegative blood samples obtained from injecting drug users should be tested for the presence of HCV RNA, and suggest that this could be done efficiently by nucleic acid testing the specimens in small pools. .
Plasma growth hormone levels were studied in 15 patients with Cushing's syndrome using several stimuli. All tests except one, were performed before treatment. No change occurred in 6 patients during acute hypoglycaemia and in 11 out of 13 after a glucose load. Arginine given intravenously to 11 subjects elicited a rise in 7 out of 8 females and 1 out of 3 males. From patients who responded to arginine infusion, 6 were insensitive to one or two of the above mentioned stimuli. A selective inhibition of the releasing mechanisms might account for the partial somatotrophin insufficiency found in Cushing's syndrome.
SUMMARY Previous studies on the serological diagnosis of rotavirus infection have utilised locally produced antibodies. In this study we have compared two commercially produced assays, an ELISA (Rotazyme, Abbott) and a newly developed assay-solid phase aggregation of coupled erythrocytes (SPACE) (Wellcome Research Laboratories), with electron microscopy (EM).The SPACE test appeared less sensitive than EM. The ELISA was shown to be as sensitive as EM but more versatile. Our experience suggests that the ELISA could be successfully incorporated into the routine of any diagnostic laboratory.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.