Objective. To establish the point prevalence of systemic lupus erythematosus (SLE) on January 1, 1992, and the incidence of SLE during 1991, in Birmingham, England, a large city with a broad ethnic mix.Methods. Six sources were used to ascertain patients with diagnosed SLE, including notification by attending and primary care physicians, the lupus patient support group, and hospital inpatient and laboratory data.Results. There were 242 SLE patients (227 females, 15 males) identified: prevalence rate 27.71100,OOO (95% confidence interval 24.2-31.2/100,000) in the population and 206.0/100,000 in Afro-Caribbean females. No significant differences in female ethnic prevalence rates by place of birth were observed. Thirty-three patients developed SLE in 1991: incidence rate 3.81 100,00O/year (95% confidence interval 2.5-5.1/100,000/ year).Conclusion. This study illustrates dramatic differences in incidence and prevalence rates in the UK, depending on ethnic group and irrespective of place of birth.Previous research from the United States has suggested that ethnicity, country of birth and of residence, socioeconomic status, sex, and age may all play a role in the etiology of systemic lupus erythem-

Acyclovir is a potent antiviral drug, of proven efficacy in the treatment of herpes simplex virus infection. Since this virus has been implicated in the aetiology of Behçet's syndrome, the effect of acyclovir on orogenital ulceration in this condition was determined in a randomized, double-blind, placebo-controlled, crossover trial. Eighteen of 22 patients entering the study completed the trial. Treatment with acyclovir failed to alleviate the frequency and severity of orogenital ulceration or other disease features.

Plasma progesterone levels were determined in 16 Beagle bitches undergoing a normal oestrous cycle. The mean concentration rose during oestrus and a peak of 20.3 ng/ml was attained early in metoestrus. Considerable variation was noted between animals in respect of the magnitude and timing of the progesterone peak. The time of the highest progesterone values ranged from three days before the end of oestrus to Day 21 of metoestrus. The mean hormone levels remained elevated throughout metoestrus. On the basis of the time of the initial rise in progesterone levels during oestrus and the oestrogen peak values in three animals, it is suggested that ovulation occurs on the first or second day of oestrus.

A 75-year-old man with a short history of cutaneous lesions of multicentric reticulohistiocytosis, preceded by a few months of a symmetrical polyarthritis is described. Within 5 months of onset of symptoms, he developed congestive cardiac failure secondary to pericardial involvement by the disease and succumbed despite therapy with cyclophosphamide and methylprednisolone. Post-mortem revealed the true extent of the disease, with nodules seen in the epiglottis and aryepiglottic folds, duodenal mesentery, pleura, pericardium and myocardium. Although the hallmarks of the disease are the papulonodular skin lesions, together with a severe, sometimes mutilating polyarthropathy, its widespread systemic nature is not often appreciated. We review five other cases in the literature with pericardial involvement and discuss aids to earlier diagnosis by synovial fluid cytology; gallium scanning is discussed as a potentially useful means of detecting the extent of systemic involvement in multicentric reticulohistiocytosis.

Sister chromatid exchanges (SCEs), a sensitive measure of chromosome damage, were counted in peripheral-blood lymphocytes from 10 patients with Behcet's syndrome receiving chlorambucil. All patients had abnormal counts. Damage was related to both daily dose and duration of therapy and was occurring at a greater rate than its repair. The patient who had been treated the longest and had received the highest total dose also had the highest SCE count. He died from acute leukaemia. SCE analysis may provide a method for detecting patients at risk from oncogenic effects of cytotoxic drugs.