Hyperglucagonaemia in cirrhotic patients and its relationship to the severity of cirrhosis and haemodynamic values

Plasma glucagon concentrations were measured in 160 cirrhotic patients (Pugh's grade A in 52 patients, Pugh's grade B in 64 patients and Pugh's grade C in 44 patients). These values were compared with plasma glucagon concentrations in 57 age and sex-matched healthy subjects. Systemic and portal haemodynamic measurements, effective renal plasma flow and creatinine clearance were recorded for each patient. Plasma glucagon levels were significantly increased in cirrhotic patients compared with healthy subjects. In addition, plasma glucagon levels were higher in cirrhotic patients with ascites than in those without ascites and were increased in relation to the severity of cirrhosis as assessed by Pugh's score. Multiple linear regression found that only Child-Pugh's score was estimated to be an independent predictor of hyperglucagonaemia in cirrhotic patients. However, in patients with different degrees of oesophageal varices and in patients without oesophageal varices, plasma glucagon concentrations were no different among the different groups of patients, but were still higher than plasma glucagon concentrations in healthy subjects. In contrast, plasma glucagon levels were negatively correlated with mean arterial pressure and systemic vascular resistance. The results of the present study suggest that impairment of liver function plays, in part, a role in increased plasma glucagon levels observed in patients with cirrhosis. In addition, these data support the hypothesis that hyperglucagonaemia may contribute, at least in part, to the pathogenesis of peripheral arterial vasodilatation in cirrhosis with portal hypertension.

Prenatal and postnatal changes of the human tonsillar crypt epithelium

The tonsillar crypt shows infiltration of lymphoid cells in the epithelium and the highly porous or discontinuous basement membrane. However, the relationship between developmental period and the significance of the disrupted epithelial basement membrane and infiltration of lymphoid cells within the human tonsillar crypt epithelium is still obscure. The present study was designed to determine the prenatal and postnatal changes of the human tonsillar crypt epithelium in 4 fetuses, 4 neonates, 1 infant, 5 children and 4 adults using immunohistochemical stains with polyclonal anti-laminin and monoclonal anti-type IV collagen antibody, and transmission electron microscope. The tonsillar crypt epithelium from all fetuses and neonates showed infiltration of many lymphoid cells and an intact basement membrane by immunohistochemistry. Transmission electron microscope revealed pores in the basement membrane through which lymphocytes passed. Tonsils from a 4-month-old infant showed focal disruption of the basement membrane by immunohistochemical staining. The tonsils from children and adults showed that there was massive disruption of the basement membrane with lymphoid cell infiltration in the tonsillar crypt epithelium by immunohistochemical staining and transmission electron microscopy. In conclusion, lymphoid cell infiltration and holes of the basement membrane of the tonsillar crypt epithelium are normal developmental findings, whereas disruption of the basement membrane of the tonsillar crypt epithelium is pathological.

Prevalence of gastric ulcer in cirrhotic patients and its relation to portal hypertension

The prevalence of gastric ulcer and its relationship to the severity of cirrhosis and degree of portal hypertension was evaluated in 245 cirrhotic patients, and compared with 245 age- and sex-matched healthy subjects. Portal and systemic haemodynamic studies were performed in cirrhotic patients. The prevalence of gastric ulcer in cirrhotic patients was 20.8%, which was significantly higher than the 4.0% found in healthy controls. Using a multivariate logistic regression model, the hepatic venous pressure gradient was found to be the only predictor of the prevalence of gastric ulcer in cirrhotic patients to present with gastric ulcer. The hepatic venous pressure gradient was significantly higher in cirrhotic patients with gastric ulcer than in those without (17.3 +/- 4.4 vs 15.5 +/- 5.0 mmHg, P = 0.01). Other variables, including sex, smoking, cardiac output and severity or aetiology of cirrhosis did not show significant differences between the two patient groups. The prevalence of gastric ulcer in cirrhotic patients whose hepatic venous pressure gradient was below 12 mmHg (4.5%) was similar to that observed in the healthy controls (4.0%). However, when the hepatic venous pressure gradient was > 12 mmHg, the prevalence of gastric ulcer (24.4%) was significantly higher than that in control subjects. However, the incidence of gastric ulcer was not related to the degree of portal hypertension. In conclusion, the prevalence of gastric ulcer in cirrhotic patients was found to be significantly higher than in the age- and sex-matched healthy subjects. Portal hypertension with a hepatic venous pressure gradient > 12 mmHg may be an important factor contributing to the increased prevalence of gastric ulcer observed in patients with liver cirrhosis.

Behavioral changes with alterations of choline acetyltransferase immunoreactivities induced by N-butyl benzenesulfonamide

N-butyl benzenesulfonamide (NBBS), one of the sulfonamide plasticizers, induced characteristic effects to Wistar rats after acute repeated exposures (300 mg/kg body weight, ip every 6 h). The signs were pica, staggering gait with hindlimb-paresis and splaying, teeth-grinding, self paw-biting and coma. The motor activity parameters showed generalized decreased mobility. The gait and hindlimb abnormalities coexisted with changes of lower motoneuron activity, ie decreased immunoreactivity of choline acetyltransferase in the lumbar spinal cord. The effects became more overt with repeated exposure to NBBS and the severity was increased. These effects were short-lived and the animals soon recovered.

Efficacy of ursodeoxycholic acid in the treatment of patients with chronic hepatitis C

A case-control study was conducted to evaluate the efficacy of ursodeoxycholic acid (UDCA) in the treatment of Chinese patients with chronic hepatitis C. Patients who failed to have sustained responses to interferon (IFN) therapy, refused to take IFN or were unsuitable for IFN treatment were enrolled into this study. The treatment group had 15 patients and they received UDCA 600 mg orally per day for 6 months. Another 15 patients with matched sex, age and initial serum alanine aminotransferase (ALT) levels were chosen as the control group. Three parameters (i.e. serum ALT levels, serum hepatitis C virus (HCV) RNA and serum cytokines) were measured before and after UDCA treatment. After the treatment period, the mean serum ALT levels in both groups were not significantly different (153.8 +/- 111.0 U/L vs 112.1 +/- 53.8 U/L, P > 0.05) and mean serum ALT level in the UDCA-treated group did not decrease after the treatment (pre-treatment vs post-treatment value: 139.1 +/- 73.1 U/L vs 153.8 +/- 111.0 U/L, P > 0.05). In addition, all of the patients with positive HCV RNA before treatment still had active HCV viraemia after the UDCA treatment. Also, the serum levels of interleukin-6 (IL-6) and the tumour necrosis factor-alpha (TNF-alpha) were not significantly different between the two groups before and after the treatment period. In conclusion, a regimen of UDCA as prescribed in the present study did not show obvious benefits in the treatment of Chinese patients with chronic hepatitis C.

Randomized controlled trial of recombinant interferon-alpha 2b in the treatment of Chinese patients with chronic hepatitis C

To evaluate the efficacy of recombinant interferon (IFN) alpha 2b in the treatment of Chinese patients with chronic hepatitis C, a randomized controlled trial was conducted in 50 chronic hepatitis C patients: 25 patients received 3 million units of subcutaneously injected recombinant IFN-alpha 2b three times per week for 6 months, and 25 patients received no specific treatment were used as controls. At the end of the IFN treatment, 19 patients (76%) in the IFN-treated group normalized serum ALT compared with only 6 patients (24%) in the control group (p < 0.01). Relapse within 6 months after the completion of treatment occurred in 13 IFN-treated patients (68%). Normalized serum ALT was seen in 6 patients (24%) in the IFN-treated group and 1 patient (4%) in the control group 6 months after discontinuation of IFN therapy (p = 0.10). The presence of serum hepatitis C virus (HCV) RNA measured by reverse transcription-polymerase chain reaction was detected at the end of the IFN treatment in all 13 patients who relapsed after cessation of therapy. In only 3 of 25 IFN-treated patients (12%) was the presence of serum HCV RNA not detectable at the end of the IFN treatment or 6 months after cessation of therapy. No patient in the control group had undetectable serum HCV RNA during the study period. Using multivariate logistic regression analysis, the low pretreatment levels of HCV RNA, measured by a quantitative branched DNA amplification assay, was the only independent predictor of a sustained response to IFN therapy (p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Injection with nondisposable needles as an important route for transmission of acute community-acquired hepatitis C virus infection in Taiwan

A prospective case-controlled study was conducted in order to determine the transmission route of community-acquired hepatitis C virus (HCV) infection in Taiwan. Thirty-eight consecutive patients (25 men and 13 women) with acute community-acquired HCV infection and 76 age (within 3 years)- and sex-matched healthy control subjects without HCV infection were enrolled. Serum anti-HCV was tested by second generation immunoassay. The sera of 26 family members from 12 families of index patients were also tested for anti-HCV. A questionnaire covering the history of blood transfusion, surgery, intravenous drug abuse, prostitute contact, dental procedures, injection, acupuncture, tattooing, and ear-piercing was conducted among patients and control subjects. Univariate analysis revealed injection with nondisposable needles was an independent risk factor (P = 0.02, odds ratio = 4.17, 95% confidence interval = 1.24-14.47) associated with HCV infection. Other risk factors were not significant. Only 2 (7.7%) family members of index patients had an anti-HCV. In conclusion, more vigorous effort to prohibit the use of nondisposable needles should be promoted to interrupt the spread of community-acquired HCV infection in Taiwan. Of note, a significant number of patients (34.2%) contracted HCV infection without identifiable risk factors. Unidentified routes need to be investigated.

Technetium-99m albumin scintigraphy in the diagnosis of protein-losing enteropathy: a case report

A 34-year-old female presenting with bilateral lower leg edema and distended abdomen was admitted to our hospital. The serum albumin was 1.42g/dl. Renal function and hepatic function were normal. Urinalysis did not show proteinuria. Tc-99m albumin scintigraphy was arranged for this patient to rule out protein-losing enteropathy. The results demonstrated loss of albumin into the intestines. We conclude that Tc-99m albumin scintigraphy of the abdomen is a valuable adjunct in the diagnosis of protein-losing enteropathy.

[Swallowing of fixed denture following general anesthesia--a case report]

Dental injury is a common complication associated with endotracheal general anesthesia. According to a study in Japan, the incidence of dental injury caused by endotracheal intubation is 0.69%. In one study in our country, evaluation of the oral condition was performed before, during and after anesthesia, and the frequency of dental trauma is as high as 12.1%. Fragment(s) of tooth or denture may cause serious, or even fatal complications. We report a case of swallowing of fixed denture following endotracheal general anesthesia. Our accident involved a 33-yr-old male who had experienced bilateral auditory impairment as a result of chronic otitis media. The patient underwent right modified radical mastoidectomy under endotracheal general anesthesia. It might well be that the patient's maxillary fixed denture was loosened at the time of endotracheal intubation. However, patient's denture was normal in appearance and not much attention was paid to it. During his stay at the post-anesthesia care unit, he might have unconsciously swallowed his denture. Verification was later made by X-ray. On careful observation, his denture was found in the feces during defecation 30 h post-operatively.

A pilot, open-labelled, phase II study using oral ribavirin in the treatment of patients with chronic active hepatitis B

BACKGROUND

Ribavirin is a synthetic purine nucleoside with demonstrated antiviral activity against several DNA and RNA viruses.

OBJECTIVES

An open-labelled pilot study to evaluate the safety and effect of ribavirin in the treatment of patients with chronic active hepatitis B (CAH-B).

STUDY DESIGN

24 CAH-B patients were treated with oral ribavirin 1200 mg daily in 3 divided doses for 4 weeks. Biochemical and virological parameters were monitored at regular interval during and after treatment.

RESULTS

The serum hepatitis B e antigen (HBeAg) and HBV DNA measured by dot-blot hybridization were positive in all patients before treatment. At the end of 4 weeks of therapy, the HBV DNA levels decreased in 15 (63%) patients and became undetectable in 1 (4%) of these individuals. The mean HBV DNA decreased from 288+/-78 pg/ml at baseline to 219+/-79 pg/ml at the end of the 4 weeks of treatment (p = 0.046). Eight weeks after cessation of treatment, HBV DNA was undetectable in 10 (42%) patients, and the mean HBV DNA was 46+/-23 pg/ml (p < 0.01 when compared to mean baseline value). Seven (29%) patients seroconverted from HBeAg positive to anti-HBe positive but no patients lost hepatitis B surface antigen (HBsAg) during the 8 weeks of follow-up. At the end of 4 weeks of ribavirin treatment, serum levels of alanine aminotransferase (ALT) decreased in all but 1 patient; only 1 patient normalized serum ALT at this time. The mean serum ALT decreased significantly from 416+/-72 IU/l at baseline to 179+/-35 IU/l at the end of 4 weeks of treatment (p = 0.001). Eight weeks after cessation of therapy, the mean serum ALT value was 151+/-32 IU/l (p < 0.001 when compared to mean baseline value) and 5 (21%) patients normalized serum ALT at this time. During ribavirin treatment, the main side effect was a decrease in the hemoglobin level which returned to the pretreatment level in each instance within 2 months after discontinuance of therapy.

CONCLUSIONS

Results of this pilot study indicated that oral ribavirin was well tolerated in CAH-B patients and resulted in lowering of serum ALT and HBV DNA values. A randomized controlled trial is needed to fully evaluate the beneficial effects of ribavirin in CAH-B patients.

Budd-Chiari syndrome due to pacemaker-induced thrombosis

We report a unique case of Budd-Chiari syndrome caused by pacemaker leads-induced thrombosis. A 34 year old female patient was subjected to a permanent pacemaker insertion because of refractory paroxysmal supraventricular tachycardia attacks related to Wolff-Parkinson-White syndrome. Three years later, another pacemaker was re-implanted because of its dislodgement. Four episodes of skin infections at the implantation site were noted thereafter. The patient developed symptoms of abdominal pain and ascites 5 years after the second pacemaker implantation. Ultrasonography and computerized tomography of the abdomen revealed hepatomegaly with ascites and dilated inferior vena cava. An echocardiogram displayed thrombus formation in the superior vena cava, the right atrium and the inlet of the inferior vena cava into the right atrium. Inferior and superior venacavogram confirmed the above findings. With the impression that Budd-Chiari syndrome was caused by pacemaker-induced thrombus, we removed the pacemaker first and thoracotomy with thrombectomy was then performed. The clinical symptoms resolved after the operation. To our knowledge, this is the first case reported in the literature and this observation supported the thrombosis theory for membranous obstruction of inferior vena cava.

Pharmacokinetics of methotrexate after intravenous and intramuscular injection of methotrexate-bearing positively charged liposomes to rats

The pharmacokinetics and tissue distribution of methotrexate (MTX) were investigated after intravenous (IV) and intramuscular (IM) injection of free MTX (treatment I), freshly prepared MTX-bearing positively charged liposomes (large unilamellar vesicles), PLUVs (treatment II), and empty PLUVs mixed manually with free MTX (treatment III), 4 mg kg-1 as free MTX to rats, using HPLC assay. After 1 min IV infusion, the plasma concentrations of MTX (Cp), the area under the plasma concentration-time curve (AUC, 173 against 314 micrograms mL min-1), the terminal half-life (t1/2, 24.0 against 412 min), the mean residence time (MRT, 13.0 against 324 min), and the apparent volume of distribution at steady state (VSS, 289 against 3370 mL kg-1) were significantly larger, but the total body clearance (CL, 23.1 against 12.8 mL min-1 kg-1), the renal clearance (CLR, 8.38 against 3.09 mL min-1 kg-1), the non-renal clearance (CLNR, 14.6 against 9.56 mL min-1 kg-1), and the amount of MTX excreted in urine (Xu, 415 against 275 micrograms) were significantly lower in treatment II than in treatment I. This could be due to the fact that some of the MTX-bearing PLUVs were entrapped in tissues and the rest were present in plasma (larger MRT and Vss in treatment II), and MTX is slowly released from MTX-bearing PLUVs (longer t1/2 in treatment II). In the present HPLC assay, the concentrations of MTX represent the sum of free MTX and MTX in MTX-bearing PLUVs (larger Cp and AUC and slower CL in treatment II). Saturable formation of 7-hydroxymethotrexate from MTX was reported in rabbit blood and nonlinear disposition of MTX was also reported in rats and rabbits (lower Xu and CLR in treatment II). After 1 min IV infusion, some pharmacokinetic parameters of MTX, such as AUC, CL, CLR, CLNR, and Xu, were significantly different between treatments I and III, but nonetheless the differences were smaller than those between treatments I and II. After both IV and IM administration, the amount of MTX remaining per gram of tissue or organ in the kidney, stomach, small intestine, and large intestine was significantly smaller in treatment II than in treatment I.(ABSTRACT TRUNCATED AT 400 WORDS)

Detection of genotype-environment interaction in case-control studies of birth defects: how big a sample size?

Detecting interactions between risk factors in case-control studies of birth defects and other conditions usually requires increasing the sample size beyond that needed to detect marginal effects. A special case of such interaction is genotype-environment interaction in which the effects of an exposure on disease risk are modified by genetic susceptibility. When case-control studies are designed to detect marginal effects of an exposure (i.e., in the whole population), under many plausible interaction schemes, no additional case and control subjects are needed to detect genotype-environment interaction. On the contrary, inclusion of genotypic information generally can improve the statistical power of the original study. Using the example of oral clefts, maternal cigarette smoking, and genetic variation at the transforming growth factor alpha gene, we illustrate sample size and power issues in designing case-control studies when prior information is available on both the marginal effects of the exposure and the genetic factor.

Membranous obstruction of inferior vena cava in Taiwan

Membranous obstruction of the inferior vena cava (MOVC) is a rare cause of Budd-Chiari syndrome. When compared to the West, the incidence of MOVC was reported to be higher in the Orient, India and South Africa. From 1979 to 1993, 16 consecutive Chinese patients (mean age 50 years) with MOVC were retrospectively evaluated. The diagnosis in these MOVC patients was usually delayed with a mean lag time of 111 months. Most of the cases were detected by a delicate ultrasonographic examination of the abdomen. Segmental narrowing of the inferior vena cava in 11 patients was the predominant type of MOVC, while five experienced a membranous obstructive type. Only one of five surgery-treated patients had a post-operation survival > 5 years, while five out of the nine patients who received conservative treatment still survived after a 6-15 year follow up. Two patients received percutaneous angioplasty (PTA). One survived 4 years and the other expired 5 years after the PTA. Two patients (12%) developed a hepatocellular carcinoma in their disease course, and the incidence was lower than in previous reports from Japan and South Africa. The incidence of hepatitis B surface antigen in MOVC did not increase in our patients compared with the general population. In conclusion, the inferior vena cava should be carefully evaluated in an ultrasonographic examination of the abdomen to increase the diagnosis rate of MOVC. Surgical intervention should be carefully justified according to the patient's symptoms and signs, the types of obstructive lesions and the expertise of the surgeons.

Association study of transforming growth factor alpha (TGF alpha) TaqI polymorphism and oral clefts: indication of gene-environment interaction in a population-based sample of infants with birth defects

In this study of infants with isolated birth defects, 69 cleft palate only cases, 114 cleft lip with or without cleft palate cases, and 284 controls with noncleft birth defects (all born in Maryland between 1984 and 1992) were examined to test for associations among maternal exposures, genetic markers, and oral clefts. A significantly higher frequency of positive family history of birth defects among both groups of oral cleft cases compared with controls was seen in these data. While there was a modest increase in the less common C2 allele at the TaqI site in the transforming growth factor alpha (TGF alpha) locus among cleft palate only infants compared with the birth defect controls, the association appeared to reflect an underlying interaction between maternal smoking and infant genotype. This apparent gene-environment interaction was also found among those reporting no family history of any birth defect. Infants carrying the rarer C2 allele who were exposed to maternal smoking of 10 or fewer cigarettes per day showed a 6.16-fold increase in risk for cleft palate only (95% confidence interval 1.09-34.7), while similar infants whose mothers smoked more than 10 cigarettes per day showed an 8.69-fold higher risk (95% confidence interval 1.57-47.8). However, the dose-response relation was not significant.

Detection of antibody to M2 mitochondrial antigen in Chinese patients with primary biliary cirrhosis

BACKGROUND

Antimitochondrial antibodies (AMA) are present in more than 90% of patients with primary biliary cirrhosis (PBC). However, AMA are not specific for PBC; they can be observed in nonhepatic disease. It has been reported that antibody of M2 mitochondrial antigen (anti-M2) is specific for PBC. The aim of the present study is to clarify the role of anti-M2 in the diagnosis of PBC.

METHODS

Sera from 27 patients with PBC, 62 normal subjects, 18 patients with chronic hepatitis B and 30 patients with chronic hepatitis C were obtained for the detection of anti-M2 and AMA. The anti-M2 assay was performed by enzyme immunoassay (EIA) and the AMA test was performed by indirect immunofluorescent method.

RESULTS

Twenty-four (88.9%) of the serum specimens from the patients with PBC and one (0.9%) of the 110 serum specimens from the non-PBC groups were positive for AMA. In contrast, twenty-five (92.6%) of the 27 PBC sera and five (4.5%) of the 110 non-PBC sera were positive for anti-M2. Most of the PBC sera contained high titers of anti-M2 and all the false-negative specimens disclosed low titers of anti-M2.

CONCLUSIONS

Although the anti-M2 assay used in the present study seemed not superior to the conventional AMA test in the sense of specificity, it had the advantage of being able to provide quantitative results. Since the presence of high titer anti-M2 is very specific for PBC, this assay may have a role in the diagnosis of equivocal PBC.

Quantitative branched DNA assay and genotyping for hepatitis C virus RNA in Chinese patients with acute and chronic hepatitis C

To determine the value of a quantitative branched DNA (bDNA) assay for detection of hepatitis C virus (HCV) RNA, 309 serum specimens were collected from 100 patients with acute or chronic hepatitis C for detection of HCV RNA by bDNA assay and reverse transcription-polymerase chain reaction (RT-PCR) assay. There were 256 samples positive by RT-PCR; 199 (78%) were also positive by bDNA assay. All but 1 of the remaining 53 samples negative by RT-PCR were also negative by bDNA assay. Combination of the two methods clearly demonstrated changes in HCV RNA titers during and after interferon (IFN) treatment. The most common genotype of HCV infection was Okamoto type II (Simmonds type 1b, 60.0%), followed by type III (type 2a, 16.5%) and type IV (type 2b, 8.2%); mixed or underdetermined types were noted in 15.3%. Patients with chronic type II HCV infection tended to have higher HCV RNA titers. These findings suggest that the bDNA assay is a reliable test for HCV RNA.

Lack of influence of recombinant human erythropoietin on parathyroid function in hemodialysis patients with secondary hyperparathyroidism

The effects of recombinant human erythropoietin (rHuEPO) treatment on parathyroid function in patients on maintenance hemodialysis (HD) with secondary hyperparathyroidism (HPT) is poorly understood. We compared the levels of serum intact parathyroid hormone (PTH) and the suppressibility of PTH by intravenous calcium infusion before and after 12 weeks of rHuEPO treatment in 8 HD patients with secondary HPT. The suppressibility of PTH by calcium infusion in HD patients was also compared with that of normal subjects. After rHuEPO treatment, in HD patients hematocrit and hemoglobin levels increased significantly from 20.1 +/- 1.3% and 6.65 +/- 0.46 g/dl to 28.7 +/- 1.0% and 9.68 +/- 0.39 g/dl, respectively. The serum intact PTH levels did not change significantly (541.9 +/- 65.3 pg/ml before versus 572.9 +/- 75.3 pg/ml after rHuEPO treatment), nor did serum ionized calcium, phosphate, magnesium, aluminum, alkaline phosphatase, and 1.25(OH)2D levels. Calcium infusion significantly increased serum ionized calcium and suppressed serum PTH levels. However, the increment in serum calcium levels and the percent decrement of serum PTH showed no significant differences before and after rHuEPO treatment in HD patients. Elevations in serum calcium levels during calcium infusions were not significantly different between normal subjects and HD patients. However, the percent maximal decrement in serum PTH level was less in HD patients both before and after rHuEPO treatment than in normal subjects (-75.4 +/- 3.9 and -76.4 +/- 4.1% versus -91.4 +/- 1.4%). We conclude that rHuEPO treatment has no influence on parathyroid function in maintenance HD patients with secondary HPT. In addition, PTH secretion is less suppressed by calcium infusion in the same group of patients.

Evaluation of sexual transmission in patients with chronic hepatitis C infection

BACKGROUND

The transmission of hepatitis C virus (HCV) by parenteral exposure is well documented. However, a proportion of patients with acute or chronic HCV infection have an unknown source of infection.

OBJECTIVES

The purpose of this study is to evaluate the role of sexual transmission in HCV infection.

STUDY DESIGN

68 patients (median age, 50 years) with chronic hepatitis C and their spouses were tested for the presence of antibody to HCV (anti-HCV) by multi-antigen and chimeric C25 antigen enzyme immunoassays and for HCV RNA by the polymerase chain reaction. Information on sexual activity and risk factors for HCV infection were obtained from all couples via a questionnaire.

RESULTS

All index patients were positive for both anti-HCV and HCV RNA. Antibody to HCV was detected in four (5.9%) of their spouses. One anti-HCV-positive spouse had a history of blood transfusion while the other three (4.4%, 95% CI = 1.5-12.2%) had no known risk factors for HCV infection and thus may have been exposed to HCV via sexual transmission. Two of these 3 spouses had positive serum HCV RNA and had identical HCV genotype to the index patients. The length of sexual exposure was significantly longer in the couples who both were anti-HCV-positive than in patients whose spouses were anti-HCV negative (median: 25 vs. 10 years, P = 0.02, Mann-Whitney test). In our 68 index patients, 96% had antibodies to the recombinant proteins from the C22 (core) and C33C (NS3) regions, and 82% and 76% had antibodies to the proteins from the NS5 and C100-3 (NS4) regions. Identical anti-HCV profiles were noted in two of the four anti-HCV-positive couples.

CONCLUSIONS

Our results indicate that sexual transmission, although uncommon, should be considered as a risk factor for HCV infection, especially in spouses who have had long-term intimate relationships with a chronic hepatitis C patient.

Minimum sample size estimation to detect gene-environment interaction in case-control designs

As genetic markers become more available, case-control studies will be increasingly important in defining the role of genetic factors in disease causality. The authors estimate the minimum sample size needed to assure adequate statistical power to detect gene-environment interaction. One assumption is made: the prevalence of exposure is independent of marker genotypes among controls. Given the assumption, six parameters (three odds ratios, the prevalence of exposure, the proportion of those with the susceptible genotype, and the ratio of controls to cases) dictate the expected cell sizes in a 2 x 2 x 2 table contrasting genetic susceptibility, exposure, and disease. The three odds ratios reflect the association between disease and 1) exposure among non-susceptibles; 2) susceptible genotypes among nonexposed individuals; and 3) the gene-environment interaction itself, respectively. Given these parameters, the number of cases and controls needed to assure any particular Type I and Type II error rates can be estimated. Results presented here demonstrate that case-control designs can be used to detect gene-environment interaction when there is both a common exposure and a highly polymorphic marker of susceptibility.

A randomized controlled trial of recombinant interferon alpha-2b in the treatment of Chinese patients with acute post-transfusion hepatitis C

To evaluate the efficacy of recombinant interferon alpha-2b in the treatment of patients with acute post-transfusion hepatitis C, a randomized controlled trial was conducted in 33 acute post-transfusion hepatitis C patients; 16 patients received 3 million units of subcutaneously injected recombinant interferon alpha-2b 3 times a week for 3 months and 17 patients without specific treatment were used as controls. At the end of the interferon treatment, 13 (81%) patients in the interferon-treated group normalized serum alanine aminotransferase compared with only six (35%) patients in the control group (p < 0.01). One year after completion of the interferon treatment, nine (56%) patients in the interferon-treated group and six (38%) patients in the control group normalized serum alanine aminotransferase (p = 0.35). Serum HCV-RNA measured by reverse transcription-polymerase chain reaction was positive in all patients at the time of enrollment and then became undetectable in 13 (81%) patients in the interferon-treated group and two (12%) patients in the control group at the end of interferon treatment (p < 0.001). One year after completion of the interferon treatment, seven (44%) patients in the interferon-treated group and two (13%) patients in the control group had persistent undetectable serum HCV-RNA (p = 0.08). Using a logistic regression model, the lower pretreatment level of serum HCV-RNA measured by quantitative branched DNA signal amplification assay was the only predictor for a favorable response to the interferon treatment in acute hepatitis C patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation of serum HCV RNA and alanine aminotransferase levels in chronic hepatitis C patients during treatment with ribavirin

To evaluate the effect of ribavirin on serum hepatitis C virus (HCV) RNA and alanine aminotransferase (ALT) levels, 22 patients with chronic HCV infection were treated with oral ribavirin 1200 mg daily in three divided doses for 4 weeks. At the end of 4 weeks treatment, the serum ALT decreased in all but one patient and became normal in three individuals. The mean pretreatment serum ALT was reduced significantly from 193 +/- 45 i.u./L to 95 +/- 16 i.u./L after 4 weeks therapy (P = 0.009). However, 8 weeks after cessation of treatment, the serum ALT rose to a mean value of 154 +/- 21 i.u./L. The mean pretreatment serum HCV RNA was not significantly decreased at the end of 4 weeks treatment (7.0 x 10(5) vs. 4.1 x 10(5) copies/mL, P > 0.05). However, serum HCV RNA levels were decreased in 12 and increased in 10 patients at the end of 4 weeks therapy. Eight weeks after cessation of therapy, the serum HCV RNA of 22 patients rose to a mean value of 4.9 +/- 10(5) copies/mL. Six patients who continued to have elevated serum ALT and positive HCV RNA after the initial 4 weeks treatment received oral ribavirin at the same dosage for an additional 24 weeks. The serum ALT again decreased in all six patients during therapy, but rose to pretreatment values by 8 weeks after cessation of the treatment. In addition, no significant changes were noted in the mean serum HCV RNA levels during and after 24 weeks of ribavirin therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis B virus infection in Asian Americans

This article summarizes studies on hepatitis B in the Asian American population and includes prevalence rates among different Asian subgroups, routes of transmission, and sequelae of both perinatal and childhood-acquired hepatitis B virus infection. Rationale for use of hepatitis B immune globulin and hepatitis B vaccine for Asian infants and vaccine for children and seronegative adults is discussed also. Chronic hepatitis B, cirrhosis, and primary hepatocellular carcinoma in adults and screening for early detection of liver cancer are reviewed.