Searching for chronic hepatitis B patients in a low prevalence area--role of racial origin.

BACKGROUND: Clinical studies for testing new drugs against hepatitis B ought to be carried out in low prevalence areas despite difficulties on patient recruitment. In such areas, relatives of chronic hepatitis B patients are considered to be at risk of acquiring the hepatitis B virus (HBV). The aim of this study was to evaluate the prevalence of HBV markers (anti-HBc, HBsAg and anti-HBs) in familial members of chronic hepatitis B (CHB) patients according to their origin (Asian or Western) in a low prevalence area, the city of São Paulo, Brazil. METHODS: Twenty three Asian CHB probands and their 313 relatives plus 31 CHB probands of Western origin and their 211 relatives were screened for HBV serological markers; the study was carried out in the outpatient clinic of the University of São Paulo School of Medicine. RESULTS: Mother to child transmission was greater in the Asian group whereas sexual transmission was more frequent in the Western group (p < 0.0001). Anti-HBc was positive in 90% and 57% of the Asian and Western parents (p = 0.0432) and in 97% and 33% of the Asian and Western brothers (p = 0.0001), respectively. HBsAg was more frequent among the Asian (66%) than the Western (15%) mothers (p = 0.0260) as well as among the Asian (81%) than the Western (19%) brothers (p = 0.0001). We could detect 110 new HBsAg-positive subjects related to the 54 index patients, being the majority (81%) of Asian origin. CONCLUSION: In low prevalence area of hepatitis B, family members and household contacts of chronic HBV carriers are at high risk for acquiring hepatitis B.

Hepatitis B virus infection in Haemodialysis Centres from Santa Catarina State, Southern Brazil. Predictive risk factors for infection and molecular epidemiology.

BACKGROUND: Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil. METHODS: This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units. RESULTS: Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection. CONCLUSIONS: Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters > or = 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.

Influência da operaçäo de Cox no tratamento da fibrilaçäo atrial em valvopatia mitral reumática: análise comparativa de resultados imediatos e tardios / Influence of Cox's surgery in the treatment of atrial fibrillation in rheumatic mitral disease: comparative analysis of immediate and long term results

Este estudo visa avaliar a operaçao de Cox no tratamento da fibrilaçao atrial (FA) de etiologia reumática em pacientes (pts) portadores de valvopatia mitral. No período de julho 1991 a junho 1994, 55 pts valvopatas mitrais reumáticos (35 dupla lesao e 19 estenose) e FA associada foram operados. A média de idades era de 51,5 anos (16 a 74 a), 47 femininos. Todos se encontravam no pré-operatório em ICC CF III ou IV. Segundo o tipo de operaçao, foram identificados dois grupos: G I-20 pts submetidos a operaçao da valva mitral e operaçao de Cox para tratamento da FA e G II - 35 pts operados apenas da valva mitral. Eco pré-operatório mostrou diâmetro de átrio esquerdo semelhante em G I e G II (5,35 e 5,57 mm; p = 0,779). Em 24 pts a valva mitral foi substituída por bioprótese de pericárdio bovino e preservada em 31. Observaram-se 3 óbitos hospitalares, sendo 1 no G I. Detectou-se FA na UTI em 82,4 por cento dos pts do G II, mantida em 76,5 por cento em período de evoluçao de 37,7 meses; no G I, 21,1 por cento pts apresentaram FA na UTI, mantida em 5,3 por cento em período de evoluçao de 37,7 meses (p = 0,0001). Seis (20,6 por cento) pts do G II apresentaram no pós-operatório episódios de embolia sistêmica (em FA) e um paciente apresentou episódio de embolia pulmonar, contra nenhum episódio detectado nos pacientes do G I (p = 0,041). Em conclusao, a operaçao de Cox mostrou-se eficaz no controle tardio da FA e prevençao de embolia, com baixa morbimortalidade, devendo ser considerada como opçao nos portadores de FA associada à valvopatia mitral.