Tropical liver abscess

Forty-one consecutive cases of liver abscesses seen at the National University Hospital, Singapore from 1988 to 1994 were reviewed. Twenty-seven cases (65%) were pyogenic, six (15%) amoebic, two (5%) tuberculous and six (15%) indeterminate. The predominance of pyogenic abscesses is in marked contrast to previous studies from the region a decade ago in which amoebic abscesses were the commonest type. The commonest pathogen causing pyogenic abscess was Klebsiella pneumoniae. Two cases were due to Mycobacterium tuberculosis, and this organism needs to be actively looked for in smears and cultures of aspirated material. As the majority of organisms isolated were resistant to ampicillin, empirical antibiotic treatment for suspected pyogenic abscess should include gentamicin or a cephalosporin. Percutaneous needle aspiration of the abscess was performed for 85% of pyogenic abscesses and surgery was necessary in only two cases because of complications. We found that percutaneous aspiration of liver abscess is helpful to confirm the diagnosis, provides a better bacteriological culture yield, gives a good outcome, and may uncover clinically unsuspected conditions like malignancy and tuberculoma which may mimic the presentation of liver abscesses. We recommend routine cytological examination of aspirated abscess material as well as stains and cultures for acid-fast bacilli.

Subcutaneously administered recombinant human beta-interferon in the treatment of chronic hepatitis B virus infection

BACKGROUND

Treatment of chronic replicative hepatitis B virus (HBV) infection is aimed at stopping viral replication and preventing the development of chronic liver disease. beta-Interferon treatment has been less well studied than alpha-interferon.

METHODS

The efficacy and tolerability of a 6-month course of subcutaneously administered human recombinant beta-interferon (rINF-beta ser) was studied and the results of a low-dose regime compared with a high-dose regime. Twenty patients (17 men and three women), aged 24-54 years, with chronic hepatitis B virus infection (all hepatitis B surface antigen-positive with detectable HBV-DNA in their sera for at least 3 months prior to therapy) were randomized into two treatment groups of 10 patients each. The low-dose group received 6 x 10(6) U/dose and the high-dose group received 30 x 10(6) U/dose, both groups receiving their respective doses three times a week initially for 1 month and continuing for a total of 6 months.

RESULTS

The treatment was well tolerated in both groups. None of the patients required dosage reduction or cessation of treatment because of side-effects. HBV-DNA decreased in all patients during treatment, demonstrating the anti-viral efficacy of rINF-beta ser, and was undetectable in 20 and 40% of patients receiving low-dose and high-dose regimes, respectively, at the end of 6 months treatment (P = N.S.). One year after completion of treatment, HBV-DNA was undetectable in 50 and 30% of patients in the low-dose and high-dose groups, respectively (P = N.S.). However, only one patient achieved seroconversion with loss of the hepatitis B surface antigen and appearance of an antihepatitis B 'e' antigen at the end of 18 months.

CONCLUSION

This study shows that subcutaneously administered rINF-beta ser is well tolerated, but the optimal dose and duration of treatment still needs to be defined by further studies.

Fine needle aspiration biopsy of small/intermediate cell tumors in the liver. Considerations in a southeast Asian population

OBJECTIVE

To assess the diagnostic problems and accuracy involved in rendering an exact cytologic diagnosis, including reference to a primary site of origin, on fine needle aspiration biopsies (FNABs) of small/intermediate cell tumors of the liver.

STUDY DESIGN

Thirty-five hepatic FNABs of small/ intermediate tumors, neuroendocrine tumors (NETs) and poorly differentiated or undifferentiated cancers occurring in adults were analyzed. Ancillary studies, including immunohistochemistry, were performed whenever necessary. All other relevant histopathologic sections and medical records were reviewed.

RESULTS

There were 26 metastases, while 9 were considered primary lesions. The aspirates were categorized into 11 NETs (pancreas 5, lung 1, liver 2, unknown primary 3); 9 undifferentiated nasopharyngeal carcinomas; 2 small cell undifferentiated carcinomas (lung 2); 4 undifferentiated carcinomas, not otherwise specified (lung 1, pancreas 1, liver 1, unknown 1); 1 lobular-ductal carcinoma (breast); 1 glioblastoma multiforme (brain); 1 ovarian carcinoma; 1 non-Hodgkin's lymphoma (liver); and 5 primary hepatocellular carcinomas.

CONCLUSION

There was histologic and/or immunohistochemical confirmation in 25 cases (71%). Some of the limitations in categorization of such tumors obtained by FNAB can be overcome by immunohistochemistry. Information gleaned from a precise cytologic diagnosis can sometimes only favor a particular primary site.

Serological profiles of hepatitis B carrier patients in Singapore with special reference to the frequency and significance of concurrent presence of HBsAg and anti-HBs

Hepatitis B serological markers were investigated in 1,132 consecutive Singaporean HBV carriers. Hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) were found concurrently in 234 carriers (234/1132 or 21%). Serum anti-HBs levels were more than 10 mIU/mL in 80 of these carriers (80/234 or 34%). There were no difference in HBeAg positive status, as well as HBV-DNA positive status in concurrent HBsAg/anti-HBs carriers compared to carriers without anti-HBs. Our results suggested that concurrent HBsAg and anti-HBs is a common serologic pattern in Singaporean HBV carriers.

Primary biliary cirrhosis--an uncommon disease in Singapore

Primary biliary cirrhosis (PBC) is uncommon in Singapore. Twelve consecutive patients with PBC were seen between 1987 and 1994 at the National University Hospital. Eleven were women and the mean age at presentation was 53 years. Three patients presented with pruritus and jaundice whilst three had decompensated cirrhosis. The remaining six patients had no symptoms attributed to their liver disease when first detected, three of them presented with associated conditions including sicca syndrome and interstitial lung fibrosis, lichen planus, and carcinoma of breast. All patients had elevated serum alkaline phosphatase and positive anti-mitochondrial antibodies. Liver histology (10/12) showed Stage II disease (2), Stage III (5) and Stage IV (3). Three patients also had co-existing gall bladder stones but their endoscopic retrograde cholangiograms were normal. The mean follow-up period was 32.6 months and four patients died during follow-up. The only male patient had liver transplantation, two patients had symptomatic treatment while the rest were treated with ursodeoxycholic acid. In conclusion, local patients tended to presented relatively early in the course of the disease with 50% being asymptomatic and in the precirrhotic Stages.

A new pre-S containing recombinant hepatitis B vaccine and its effect on non-responders: a preliminary observation

Nine healthy subjects who had no detectable antibody response when initially vaccinated with hepatitis B vaccine (plasma derived and/or yeast derived) were revaccinated with three 20 micrograms doses of a new recombinant hepatitis B (HB) vaccine (SCI-B-VAC) derived from Chinese hamster ovary (CHO) cells and consisting of both the major S protein and the minor pre-S (S1 and S2) proteins of the viral coat. Seroconversion was successful in 78% of these non-responders after the second dose and just before the third vaccination. The geometric mean titres of the antiHBs were 587 iu/l one month after the course of vaccination. This study, though preliminary, indicated that pre-S containing CHO vaccine is effective in inducing antibody response in S-vaccine non-responders and also suggested that the added pre-S region in HBV vaccine helps antiHBs production. Frequency of HLA B46 and B15 were higher in non-responders compared to normal subjects (P = 0.04) supporting the possibility that genetic factors may modulate the immune response to HB vaccination.

The effect of polyunsaturated phosphatidyl choline in the treatment of acute viral hepatitis

BACKGROUND

Polyunsaturated phosphatidyl choline is a preparation often advocated for diseases of the liver.

METHODS

In a randomized open controlled trial, a preparation of polyunsaturated phosphatidyl choline, at a dose of 900 mg orally daily, was given to 22 patients with acute viral hepatitis. A control group of 25 patients was not treated.

RESULTS

Serial serum bilirubin and alanine amino transferase levels were measured up to 12 weeks. The falls in their levels after 2 and 5 weeks, and the lengths of time to their normalization, were not significantly different in the treated group compared to the control group.

CONCLUSION

The results indicated that polyunsaturated phosphatidyl choline had no beneficial effect on the course of acute viral hepatitis.

Treatment of hepatitis B surface antigen carriers in the early stage of the infection using recombinant alpha-interferon with steroid priming

BACKGROUND

Alpha-interferon has been found to inhibit hepatitis B virus (HBV) replication in Chinese patients with chronic HBV infection although a sustained effect was rarely achieved in those with normal pretreatment serum alanine amino transferase (ALT) levels. Prednisolone priming has been found to be beneficial over treatment with interferon alone in these subjects. We studied the effect of steroid pre-treatment followed by recombinant interferon alpha-2a in the treatment of asymptomatic HBV carriers with positive hepatitis Be antigen (HBeAg), hepatitis B viral DNA (HBV-DNA) and minimal changes in liver histology.

METHODS

The treatment regimen included a 6-week prednisolone priming, a 2 week rest followed by 14 weeks of three times weekly 9 mega units of interferon alpha-2a injection and 52 weeks of follow-up. There were seven patients in the treatment group and seven controls.

RESULTS

The mean age, pre-treatment ALT (normal in all except for one in each of the treatment and control groups), HBV-DNA levels and histological scores were similar in the two groups. Serum HBV-DNA levels fell in six patients during treatment and became undetectable in two of them by the end. During follow-up, serum HBV-DNA returned to pre-treatment levels in all patients. None of the treated patients had HBeAg sero-conversion and none of the controls had spontaneous clearance of HBV-DNA or sero-conversion of HBeAg. No improvement of liver histology was observed in any of the treated patients. There were only mild flu-like side-effects noted and interferon alpha-2a was well tolerated at the doses given among treated patients.

CONCLUSION

Prednisolone priming followed by interferon alpha-2a treatment has no beneficial effect on HBV carriers in the early stages of chronic hepatitis B infection.

Bile cytology. Diagnostic role in the management of biliary obstruction

Thirty satisfactory bile specimens from 21 patients (13 with cancer and 8 with benign conditions) were reviewed to assess the diagnostic role of bile cytology in the management of biliary obstruction. Smears were malignant in 5 instances, suspicious in 1, atypical in 2 (8 in the positive group) and negative in 22. There were no false positives. The diagnostic sensitivity was 38%, specificity 100% and overall accuracy 57%. Of interest were (1) hepatocellular carcinoma, causing obstruction in three patients; (2) metastatic colonic adenocarcinoma, causing obstruction in another instance; (3) positive cytodiagnosis in a patient who developed biliary stricture following laparoscopic cholecystectomy; and (4) detection of acidfast bacilli in bile from a case of tuberculous pseudotumor mimicking a hepatic malignancy. Bile cytology is a simple, inexpensive means of obtaining tissue confirmation of neoplastic and specific inflammatory causes of biliary obstruction. It is a useful adjunct to other techniques in this era of fiberoptic diagnostic procedures. Cell block sections should be prepared whenever possible.

Immunogenicity and safety of an inactivated hepatitis A vaccine amongst Singaporeans

The immunogenicity and reactogenicity of an inactivated hepatitis A virus (HAV) vaccine was studied in healthy Singaporean adult volunteers. One hundred and forty healthy volunteers with normal alanine (ALT) and aspartate (AST) transaminases and no previous exposure to HAV, received three 1 ml doses (720 ELISA units) of an inactivated HAV vaccine (Smithkline Beechams Biologicals) following a 0, 1, 6 months vaccination schedule. All subjects were asked to record and grade the severity of any reactions for three consecutive days after each dose. Serum ALT and AST as well as anti-HAV were measured at 0, 1, 2, 6 and 7 months after the first vaccine dose. Anti-HAV seroconversion occurred when levels rose above 40 mIU/ml. Eighty-five percent of vaccinees seroconverted after the first innoculation and 99% after the second injection. All vaccinees seroconverted after the third dose. Geometric mean anti-HAV titers (GMTs) were, respectively, 119, 391, 4406 mIU/ml one month after each of the three doses. The most common side effect was transient pain and tenderness at the vaccination site. No elevation of ALT or AST levels were noted during the study period. The inactivated hepatitis A vaccine used in this study is safe and highly immunogenic in the local adult population. Two doses one month apart appeared to give adequate protection.

Aspiration cytology of liver abscesses. With an emphasis on diagnostic pitfalls

Clinical and imaging features of liver abscesses are not specific. Necrotic hepatic neoplasms, primary or secondary, can mimic abscesses, and vice versa. Thirty-eight patients who had cytologic confirmed abscesses were analyzed. There was clinical, radiologic and cytologic concurrence in 27 patients. In six cases the clinically suspicious lesion turned out to be inflammatory. The remaining five were malignant. There were four amebic and three tuberculous cases in this series. Cytologically, pyogenic abscesses contained a heavy, neutrophilic, inflammatory exudate with nuclear debris. By comparison, amebic cases contained more necrotic debris, with degenerating hepatocytes and fewer inflammatory cells. Acid-fast bacilli were identified in two tuberculous abscesses; however, only one contained caseous necrotic material and epithelioid cells. A potential pitfall in the cytologic diagnosis of a case of inflammatory pseudotumor is emphasized. The diagnosis of liver abscess should be established by clinical and imaging findings in conjunction with needle aspiration.

Tuberculous pseudotumor causing biliary obstruction. Report of a case with diagnosis by fine needle aspiration biopsy and bile cytology

Hepatobiliary tuberculosis is a rare but distinct clinical entity. We report an unusual case of biliary tract obstruction due to localized hepatic tuberculosis with periportal tuberculous adenitis. The lesion mimicked a malignancy clinically and radiologically. Fine needle aspiration biopsy revealed granulomas, epithelioid histiocytes and Langhans' giant cells. The cytodiagnosis was confirmed by identification of acid-fast bacilli in the bile cytology and isolation of Mycobacterium tuberculosis by culture. The patient responded to antituberculosis therapy. The usefulness of bile cytology in the diagnostic management of biliary tract obstruction is illustrated.

Chili protects against aspirin-induced gastroduodenal mucosal injury in humans

Capsaicin, the pungent ingredient of chili, has a gastroprotective effect against experimental gastric mucosal injury in animals. Such an effect has not, however, been documented in humans to date. Eighteen healthy volunteers with normal index endoscopies underwent two studies four weeks apart. Each subject took 20 g chili orally with 200 ml water in one study and 200 ml water in another study. In each case this was followed half an hour later by 600 mg aspirin BP with 200 ml water. Endoscopy was repeated 6 hr later. Gastroduodenal mucosal damage was assessed by a previously validated scoring system. The median gastric injury score after chili was 1.5 compared to 4 in the control group (P < 0.05), demonstrating a gastroprotective effect of chili in human subjects.

Chili--protective factor against peptic ulcer?

The aim of the present study was to determine the frequency and amount of chili taken by peptic ulcer patients and control subjects. One hundred three Chinese patients with peptic ulcer and 87 control patients were interviewed using a standard questionnaire. Those subjects who deliberately avoided chili use because of symptoms or advice from friends or medical practitioners were excluded. The median number of times of chili use per month was eight in the ulcer group (25-75% quartiles 1-30) compared to 24 (8-56) in the control group (P < 0.001). The median amount of chili used per month was 312 units (25-75% quartiles 38-899) in the ulcer group compared to 834 units (274-1892) in the control group (P < 0.001). The odds ratio of having peptic ulcer disease, adjusted for age, sex, analgesic use, and smoking by multiple logistic regression, was 0.47 (95% confidence intervals: 0.25-0.89) for subjects who had a higher intake of chili both in terms of frequency as well as amount used compared to those who took less chili. Our data support the hypothesis that chili use has a protective effect against peptic ulcer disease.

Study on the comparative immunogenicity of a recombinant DNA hepatitis B vaccine containing pre-S components of the HBV coat protein with non pre-S containing vaccines

A new recombinant hepatitis B vaccine (SCI-B-VAC), derived from Chinese hamster ovary (CHO) cells and consisting of both the major S protein and the minor pre-S1 and pre-S2 proteins of the viral coat were compared with two yeast-derived vaccines containing only S proteins (B-Hepavac II and Engerix-B) for immunogenicity in human volunteers in a randomized controlled study. Two hundred and ninety-five healthy subjects completed the 12 month follow up. There was no difference in the mean age and sex distribution among the three study groups. Seroconversion rates for all the three groups were similar at months 6, 9 and 12. However, hepatitis B surface antibody (anti-HBs) geometric mean titres (GMT) were significantly higher with 10 micrograms SCI-B-VAC and 20 micrograms Engerix-B than with 10 micrograms B-Hepavac-II at months 6, 9 and 12. SCI-B-VAC at month 6 also showed a significantly higher anti-HBs GMT than Engerix-B (295 vs 143 miu/mL, P < 0.02).

Fine needle aspiration biopsy of hepatocellular carcinoma. Diagnostic dilemma at the ends of the spectrum

A diagnostic dilemma exists at the extreme ends of the spectrum in the cytodiagnosis of hepatocellular carcinoma (HCC). The cytologic features of fine needle aspiration biopsies from 30 well- and 16 poorly differentiated HCC were reviewed and the adjunctive role of serum alpha-fetoprotein (AFP), hepatitis B virus (HBV) markers and radiologic findings evaluated. Some subtle features noted in very well differentiated HCC include small tumor cell size with increased nuclear/cytoplasmic ratio, monotony of atypia, hepatocytic tumor giant cells and narrow trabeculae with tendency for cell dissociation. Useful features in poorly differentiated HCC include cell dehiscence, large cells with ovoid nuclei and thickened nuclear membranes, and one or more increasingly prominent nucleoli, with some assuming a reniform configuration. The serum AFP levels are not always elevated. Positive HBV markers, cirrhosis and compatible imaging findings are suggestive but not diagnostic. The general inclination, however, is still toward a diagnosis of HCC if the aspirate is from a focal lesion or lesions in a hepatitis B surface antigen-positive, cirrhotic liver. Cell block sections provide histologic confirmation.

The pattern of functional and organic disorders in an Asian gastroenterological clinic

The aim of the present study was to determine the pattern of structural and functional disorders encountered in an Asian gastroenterological clinic and to compare this pattern with findings from Western centres. Consecutive new patients (totalling 2384) attending the clinics of two consultant gastroenterologists were studied. Of these, 2141 suffered from gastroenterological problems. One thousand and sixty-three (49.6%) had structural diseases, the commoner ones being liver disease, peptic ulcer, malignancy, haemorrhoids and gallstones. The remainder who were found to have no structural disease (n = 1078; 50.4%) were deemed to have functional disorders including non-ulcer dyspepsia, irritable bowel, simple constipation and functional diarrhoea. The proportions of functional and structural disease were similar to those in the West. Major differences included a higher frequency of hepatoma and a lower frequency of inflammatory bowel disease and gastro-oesophageal reflux in the present series.

The colonic air insufflation test indicates a colonic cause of abdominal pain. An aid in the management of irritable bowel syndrome

We evaluated a standardized colonic air insufflation test in patients investigated for abdominal pain; 195 patients were evaluable. Of 164 patients with functional abdominal pain, 100 of the 128 (78%) with irritable bowel syndrome diagnosed on the basis of two or more Manning criteria (group A) had positive tests, compared with 19 of the 36 (53%) with functional abdominal pain not satisfying the diagnostic criteria for irritable bowel syndrome (group B). Eight of the 10 patients (80%) with structural colonic disease had positive tests (group C), and 3 of the 21 patients (14%) with structural noncolonic causes of abdominal pain (group D) had positive tests (group A vs. B, A vs. D, and C vs. D, p < 0.01). The air insufflation test had a sensitivity of 78% for the diagnosis of colonic pain and a specificity of 61%. The positive predictive value was 83% and the negative predictive value 54%. Sequential tests by two independent observers on 26 consecutive patients showed no interobserrer variation. The colonic air insufflation test warrants further evaluation as an adjunct to the Manning criteria in the diagnosis of irritable bowel syndrome. It can also serve as an investigative tool to define a subset of patients with functional abdominal pain who do not fulfill the current criteria for irritable bowel syndrome yet whose pain actually originates from the colon.

Uncommon presentation of typhoid fever: a case report

A 24-year-old Chinese woman was admitted for cholestatic jaundice following a short history of fever associated with headache and diarrhoea. She had mild hepatomegaly. Initial laboratory investigations were non-contributory. A percutaneous liver biopsy revealed inflammatory changes more in keeping with a systemic infection than a primary hepatitic problem. Repeat blood and stool cultures finally grew salmonella typhi. Jaundice is a rare manifestation of typhoid fever; it occurs in less than one-third of patients with hepatomegaly. Such a presentation may mimic primary hepatic infections. Awareness of this rare occurrence in typhoid fever would help in early diagnosis and therapy.

Augmentin-induced cholestatic jaundice--a case report

A case of cholestatic jaundice following treatment with Augmentin is reported. The awareness of hepatotoxicity due to drug should help to avoid unnecessary invasive procedures in the evaluation of this reversible condition.

Pill-induced esophageal ulcer

We describe nine cases of esophageal injury associated with the ingestion of prescribed medications. Antibiotics were the most commonly implicated drugs. Odynophagia, retrosternal chest pain and dysphagia were the usual presenting symptoms. The typical endoscopic finding was that of discrete ulcers in the mid-esophagus. All patients recovered uneventfully with discontinuation of the offending drug and symptomatic treatment. Drug induced esophageal injury should be considered in patients presenting acutely with the above mentioned symptoms and having discrete esophageal ulcers on endoscopy.

Short report: prednisolone withdrawal followed by lymphoblastoid interferon in the therapy of adult patients with presumed childhood-acquired chronic hepatitis B virus infection

Eighteen patients with presumed childhood acquisition of chronic hepatitis B virus infection were initially entered into this randomized controlled trial. Twelve were treated with prednisolone for 4 weeks followed, after a 2-week gap, by thrice weekly lymphoblastoid alpha-interferon for 12 weeks. Two of these had previously acted as untreated controls. Three of the 12 patients (25%) [who were initially hepatitis B virus (HBV) surface antigen (HBsAg), 'e' antigen (HBeAg) and HBV-DNA positive] became HBeAg and HBV-DNA negative during therapy and remained so after 12 months post-therapy follow-up. One of these also lost HBsAg. A further two patients lost HBeAg and HBV-DNA during therapy but relapsed 6 and 9 months later. Two additional patients were HBV-DNA negative but HBeAg positive at the end of follow-up. None of the eight untreated control patients seroconverted during an identical follow-up period. Two further patients were HBsAg and HBeAg positive but HBV-DNA negative at the start of therapy. These were omitted from the final analysis: both subsequently lost HBeAg. The treatment response was associated with a rise in aspartate aminotransferase, peaking 2-6 weeks after prednisolone withdrawal, loss of HBV-DNA 0-8 weeks later and subsequent normalization of liver function tests. Treatment was well tolerated.

Peliosis hepatis: a case report

A 54-year-old man who presented with marked hepatomegaly and a liver scan suggestive of an infiltrative malignancy was found to have peliosis hepatis caused by androgenic steroids. A detailed and repeated drug history is necessary for making the correct diagnosis. Withdrawal of the offending drug is indicated and may result in reversal of this serious form of hepatic toxicity.

Hepatitis A sero-epidemiology in Singapore: a changing pattern

Sera from 896 healthy volunteers between 15 and 56 years old were tested in 1987-1991 for immunoglobulin G antibody against the hepatitis A virus (IgG anti-HAV). The overall seroprevalence rate of IgG anti-HAV was 27%: it increased from 0.9% in the 10-19 years age group to 48.1% in the 40-49 years age group and was 100% in subjects over 50 years. There was no difference in anti-HAV seroprevalence between the sexes (29% among men and 26% among women) and races. A downward trend in anti-HAV seroprevalence was seen from 1987 (33%) to 1991 (21.4%). The level of exposure to the hepatitis A virus has decreased when compared with data obtained in 1975 and 1984-1985. Hepatitis A virus infection is no longer an infection of children and adolescents locally.

Low frequency of endoscopic esophagitis in Asian patients

The aim of this study was to determine the frequency of endoscopic esophagitis in patients seen for upper gastrointestinal complaints in an Asian center. We studied a consecutive series of 11,943 patients undergoing diagnostic esophagogastroduodenoscopy at our unit over a 10-year period. Three hundred and eighty-nine patients (3.3%) had endoscopic esophagitis with no other significant lesion (primary esophagitis), whereas 143 (1.2%) had esophagitis associated with peptic ulcer or gastric or duodenal malignancy (secondary esophagitis). In contrast, peptic ulcer was diagnosed in 2,787 patients (23.3%) and gastric carcinoma in 286 (2.4%). The reported frequency of endoscopic esophagitis among patients undergoing endoscopy in Western countries varied from 9 to 23%. Our data therefore show that endoscopic esophagitis is much less common in Singaporean patients.

Analysis of cost-effectiveness of different strategies for hepatocellular carcinoma screening in hepatitis B virus carriers

A mathematical model was used to calculate the efficacy of screening to detect hepatocellular carcinoma at a resectable stage in hepatitis B virus carriers. Data relating to tumour incidence, efficacy of screening tests and tumour growth times were obtained from a literature review. Various tests were costed according to charges currently prevailing at the authors' institution. The cost per early tumour detected is inversely proportional to tumour incidence. It is relatively low for populations with high incidences of hepatocellular carcinoma for example, male carriers over the age of 30. Both the costs and the proportions of early tumour detected increase with increasing frequency of screening. However, the use of ultrasonography at 10 monthly intervals or both ultrasonography and alpha-fetoprotein estimation at yearly intervals will detect 90% of tumours early at a cost of S$20,000 (US$11,800) per early tumour detected. The results would be significantly altered if tumour growth times were markedly different from those reported in the literature.

Inflammatory bowel disease: an uncommon problem in Singapore

Fifty patients with inflammatory bowel disease (ulcerative colitis, 40; Crohn's disease, seven; indeterminate colitis, three) treated in one gastroenterology unit in Singapore over a 10 year period were reviewed. Clinical features were similar to those described in Western patients. Of the three main races of Singapore it was found that Indians are more susceptible to these diseases than Chinese or Malays. A survey of all gastroenterologists in Singapore indicated a possible prevalence of 8.6 per 100,000 people for ulcerative colitis and 1.3 per 100,000 people for Crohn's disease. These prevalence rates are much lower than those reported for Western populations.

Recombinant DNA hepatitis B vaccine containing Pre-S components of the HBV coat protein--a preliminary study on immunogenicity

A novel recombinant hepatitis B vaccine, trademarked Sci-B-Vac, was evaluated for safety, tolerability and immunogenicity in an open label trial performed in Singapore. The experimental vaccine, derived from Chinese hamster ovary (CHO) cells, consists of hepatitis B surface antigen (HBsAg) particles harbouring all three viral envelope polypeptides, the major S protein and the minor Pre-S2 and Pre-S1, in their glycosylated and non-glycosylated forms. The vaccine was administered intramuscularly at 0, 1 and 6 months. No unexpected adverse effects were observed. A high level anti-HBs response to Sci-B-Vac was indicative of its immunogenicity. Subsequent to the third injection, 100% and 92% of the 10 micrograms and 5 micrograms dose recipients, respectively, were seroprotected (anti-HBs titres greater than or equal to 10 mIU ml-1). Moreover, the geometric mean titres (GMT) of the anti-HBs response were very high: 2687 and 1473 mIU ml-1, respectively. An immunogenic advantage of Sci-B-Vac was also suggested by the rapid onset of antibody response: 96% of the 10 micrograms dose recipients were seroprotected with a GMT of 159 mIU ml-1, prior to the third injection.

Seroprevalence of antibodies to the hepatitis C virus in Singapore

The prevalence of antibodies to the hepatitis C virus (anti-HCV) in Singapore was assessed using a recombinant-based enzyme linked immunoassay system. 1004 serum samples were obtained from normal subjects (463), hemodialysis patients (112), hepatitis B virus (HBV) carriers (188), patients with hepatocellular carcinoma (HCC) (58) and patients with non-hepatitis B virus related liver diseases (183). Anti-HCV was found to be positive in 1.7% of healthy subjects, and in 20% of patients on regular hemodialysis. Three percent of HBV carriers were positive for anti-HCV. Twelve percent of patients with acute hepatitis with no known causes and 20% patients with chronic hepatitis with no known causes were positive for anti-HCV. Among patients with cirrhosis for which no known causes were found 33% were positive for anti-HCV. Thirty six percent of patients with HCC not associated with the presence of HBsAg were positive of anti-HCV. None of the patients with known causes of liver disease were positive for anti-HCV.

Fine needle aspiration biopsy of hepatocellular carcinoma. Some unusual features

The cytologic features of fine needle aspiration smears from 28 hepatocellular carcinomas (HCC) were reviewed. All aspirations except one were guided. There were 14 well-, 11 moderately and 3 poorly differentiated HCC. The better-differentiated HCC were characterized by similarity of the tumor cells to hepatocytes (83%), cohesive cell clusters with a trabecular arrangement (72%) and presence of sinusoidal endothelial cells (66%). Other features included bile production (38%), atypical hepatocytic naked nuclei (52%), acinar formation (31%), intracytoplasmic vacuoles (14%) and abnormal vascular patterns (14%). Poorly differentiated HCC showed dyshesive pleomorphic cells. Unusual cytologic features from a well-differentiated HCC with fatty change and an HCC with a prominent acinar component are described. The identification of fatty change in dissociated well-differentiated hepatocytes or cytologic features suggestive of an adenocarcinoma do not preclude the diagnosis of HCC. The usefulness of cell blocks is emphasized.

Acid and gastric ulcer pain

We have shown previously that acid is one factor, although not the only one, in the pathogenesis of duodenal ulcer pain. In the present study patients with gastric ulcer were endoscoped without sedation or premedication. Under direct vision the ulcer craters were infused sequentially with 0.1 N HCl and normal saline, the sequence of infusion being randomized and double blind. Typical ulcer pain occurred in seven of 19 patients during acid infusion compared with one with saline (p = 0.023). Two patients who developed pain on acid were rechallenged after their pain disappeared, and typical pain recurred in both. Acid therefore has a definite role in the pathogenesis of gastric ulcer pain.

Chronic hepatitis B infection in Singapore

Four hundred and four patients (273 men, 131 women) aged 3 to 85 years with chronic Hepatitis B virus (HBV) infection seen during a five year period were analysed. At presentation, 177 patients (44%) were Hepatitis B e Antigen (HBeAg) positive (mean age 32 years) and 217 patients (54%) were anti-HBe-positive (mean age 40 years). Ten patients (2%) were negative for HBeAg and anti-HBe. Serum HBV-DNA was detected in 169 patients (42%). 85% of the HBeAg-positive patients had detectable serum HBV-DNA and 9% of the HBeAg-negative patients were positive for serum HBV-DNA. The mean serum Alanine amino-transferase (ALT) and Aspartate amino-transferase (AST) levels were higher in HBeAg-positive patients (75 and 52 iu/l) than in HBeAg negative patients (46 and 37 iu/l) (P less than 0.001). Liver biopsies were performed in 135 patients. Fifty-three (39%) had minimal changes, 61 (45%) chronic hepatitis (CPH, CLH & CAH) and 21 (16%) cirrhosis. There was no significant difference in the histologic distribution between HBeAg-positive and HBeAg-negative groups. Two hundred and fifty eight patients were followed up for a mean duration of 2 years (range 3 to 108 months). The cumulative probability of clearing HBeAg at the end of the first, second and third year were 14%, 16% and 18% respectively. Of these, the cumulative probability of developing anti-HBe over one, two and three years were 8%, 9% and 11% respectively. Reversion to HBeAg occurred in 1.5% of patients who were HBeAg-negative at presentation and 11% of HBeAg-positive patients who cleared HBeAg.(ABSTRACT TRUNCATED AT 250 WORDS)

Horizontal or vertical transmission of hepatitis B virus? A serological survey in family members of hepatitis B carriers in Singapore

Hepatitis B serology was performed on 270 family members of 78 hepatitis B carriers and hepatitis B e antigen status determined in those found to be HBsAg positive. The mean age of index patients was 38 years (range 3-74) and that of family members was 28 years (range 1-71). 67 family members (25%) were HBsAg positive. The proportions of family members positive for HBsAg and those negative for HBsAg but positive for anti-HBs and/or anti-HBc were 25% and 20% for children, 10% and 68% for spouses, 36% and 26% for siblings and 29% and 55% for parents. For children of index parents the proportions positive for HBsAg and those negative for HBsAg but positive for anti-HBs and/or anti-HBc were similar whether the index patient was the mother (24% and 24%) or the father (26% and 18%). Our results suggest that horizontal transmission is a significant mode of spread of hepatitis B within the family in Singapore.

Hepatocyte hepatitis B surface antigen expression in chronic hepatitis B virus carriers in Singapore: correlation with viral replication and liver pathology

The hepatocyte hepatitis B surface antigen (HBsAg) expression in 149 liver biopsies from 124 chronic hepatitis B virus (HBV) carriers was correlated with serum HBV DNA status and histologic activity. Hepatocyte HBsAg was stained by the peroxidase-antiperoxidase method and serum HBV DNA was determined by dot blot hybridization. Sixty-five biopsies (44%) showed minimal changes (MC), 82 biopsies (55%) showed chronic liver disease (CLD) and 2 biopsies (1%) showed hepatocellular carcinoma. Hepatocyte HBsAg was found in 144 biopsies (97%). It was present in the cytoplasm of 141 specimens (95%) and/or plasma membrane of 48 specimens (32%). Approximately half (45%) of the cytoplasmic HBsAg-positive biopsies showed discrete distribution, while the other half (55%) were grouped. Fifty-five per cent (77 of 141) of cytoplasmic HbsAg-positive biopsies had CLD, while 44% (62 of 141) showed MC. There was no relationship between the presence of cytoplasmic HBsAg or its topographic distribution with disease activity. Membrane HBsAg distribution was similar for both groups of patients (MC vs CLD: 25 of 65 (38%) vs 23 of 82 (28%); P = NS). Serum HBV DNA was detected in 98 patients (66%) and was seen mostly in association with CLD (CLD vs MC: 61% vs 39%, P less than 0.001). It was also detected more often in the sera of patients with membrane HBsAg than in those with cytoplasmic HBsAg staining (41 of 48 (85%) vs 97 of 141 (67%); P less than 0.02). However, discrete distribution of cytoplasmic HBsAg was associated with positive serum HBV DNA when compared with grouped distribution (52 of 63 (83%) vs 43 of 78 vs (55%); P less than 0.005).

A radiological survey of diverticulosis in Singapore

Three hundred and sixty one consecutive barium enemas done at a general hospital were reviewed prospectively to determine the frequency and anatomic distribution of diverticulosis in Singapore. The frequency of 28% is comparable to previous American and European studies and higher than previous Asian studies. There was also a predominance of purely right-sided disease with the caecum and/or ascending colon involved in 71% of patients. This anatomic distribution of diverticulosis is quite different from that seen in Caucasian populations where the disease mainly involves the left side of the colon and is probably a function of genetic and racial factors.

Hepatitis B vaccination: half dose recombinant DNA hepatitis B vaccine (B-Hepavac II) is as immunogenic as the full recommended dose in healthy adults

Sixty-seven healthy adult volunteers aged 20-40 years with no previous exposure to hepatitis B virus were randomized to receive either a 10 micrograms or 5 micrograms dose of recombinant DNA hepatitis B (HB) vaccine (B-Hepavac II) intramuscularly at 0, 1 and 6 months. Two months after the third injection 100% of subjects had seroconverted: 97% of the 10 micrograms group and 91% of the 5 micrograms group had antibody to HB surface antigen (anti-HBs) levels greater than 10 iu/L. The geometric mean titres (GMT) of anti-HBs levels at this time were 891 iu/L in the 10 micrograms dose group and 923 iu/L in the 5 micrograms dose group. These differences were not significant. Adverse effects included fever and mild pain at the injection site. The reduced dose of 5 micrograms was as effective as the standard 10 micrograms dose.

The diagnostic yield of upper gastrointestinal endoscopy in the investigation of anaemia

Computer records of patients endoscoped over a 34-month period were studied to assess the diagnostic yield of gastrointestinal endoscopy in patients with anaemia. Patients with obvious gastrointestinal bleeding and known gastrointestinal pathology were excluded. On hundred and thirty-six patients were endoscoped for anaemia. Eighty-three of them (61%) had iron deficiency anaemia and 53 (39%) had other types of anaemia. The ages of the patients with iron deficiency anaemia (mean 56 years) were significantly lower than those of other anaemias (means 65 years), (p less than 0.003). Patient characteristics were otherwise comparable. There were significant endoscopic findings (ulcers, carcinoma and haemorrhagic or erosive gastritis) in 26 of 83 patients (31%) with iron deficiency anaemia, in 11 of 53 patients with other anaemias (21%) and 37 of 136 patients (27%) combined. Significant endoscopic findings were found in 506 of 2224 patients (23%) endoscoped during this period who were not anaemic, did not have obvious gastrointestinal haemorrhage and were not known to have gastrointestinal diseases. The diagnostic yield for iron deficiency anaemia was significantly higher than for the non anaemic group (p less than 0.05). There was no difference between the diagnostic yields of iron deficiency and other anaemias, other anaemias and the non anaemic group, or total anaemias and the non anaemic group. Gastrointestinal symptoms and history of analgesic or steroid usage did not appear to increase the incidence of gastrointestinal lesions in either iron deficiency anaemia or other anaemias. Twenty-three of 41 patients (56%) who had no cause for anaemia found at the end of all investigations were colonscoped.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytological diagnosis from fine needle aspiration biopsy of the liver

One hundred and six fine needle aspiration biopsies (FNAB) of the liver were performed on 99 patients to rule out hepatic malignancy. Biopsies were performed with CT guidance (60), ultrasonography (40), fluoroscopy (3), by direct palpation (2) and intra-operatively (1). The smears and cell blocks were reviewed and the cytologic diagnoses were made after clinicopathologic correlation. Eight cases were excluded (six non-diagnostic and two mislaid). Fifty-two were positive, 2 suspicious and 44 negative for malignancy. There were no false positive results. The sensitivity for malignancy was 84.4%, the specificity was 100% and the predictive value of positive results was 100%. The false negative rate was ten out of 44 cases (22.7%). Of the malignant aspirates, there were 27 hepatocellular carcinomas, 21 metastases and four carcinomas of unknown histogenesis. Common benign lesions included abscesses, cysts, cirrhosis and steatosis. For FNAB to be an effective diagnostic procedure, adequate representative sampling, cell block preparation for appraisal of histological architecture and experience in cytomorphologic interpretation are necessary to increase yield and enhance precision of diagnosis.

The site of recurrent duodenal ulcer

The aim of this retrospective study was to determine the site of recurrent duodenal ulcer in relation to the site of the index ulcer. One hundred and thirty-five patients who had recurrent duodenal ulcer after documented healing of an index ulcer were studied. The recurrent ulcer was more likely to occur in the anterior bulb if the index ulcer was anterior (35 of 58 = 60%) than if the index ulcer was not anterior (29 of 77 = 38%, p less than 0.01). However, the likelihood of a recurrent ulcer on the posterior wall of the bulb was not significantly different whether the index ulcer was posterior (11 of 36 = 31%) or not (22 of 99 = 22%, p less than 0.24). Three of 20 patients (15%) who initially presented with bleeding bled again with their recurrent ulcers, compared with eight of 115 patients (7%) who first presented with dyspepsia only (p = 0.39). Thirteen patients were assessed independently by two endoscopists to determine ulcer site. Their assessments concurred for 12 (92%).

Endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy--a Singapore experience

We performed endoscopic retrograde cholangiopancreatogram (ERCP) on 200 patients over a four and a half year period. The duct of interest was successfully cannulated in 173 cases (87%). The most common indications were obstructive jaundice, cholangitis, chronic upper abdominal pain and suspected pancreatic disease. The commonest findings were cholelithiasis and malignant strictures of the common bile duct (CBD). Forty seven patients (27%) had normal examinations. Sixty-two of 87 (71%) patients with choledocholithiasis underwent endoscopic sphincterotomy (ES). The success rate for active stone extraction was 82% (27/33) while 64% (14/22) of patients managed expectantly cleared their CBD stones spontaneously after ES. The immediate complication rate of ES was 13% and included pancreatitis, stone impaction, cholangitis and bleeding. There was no complications amongst patients who underwent ERCP alone and no mortality in this series. Twenty three patients (26%) with choledocholithiasis proceeded to surgery because the stones were considered too large to remove endoscopically. One patient had endoscopic stone removal without prior ES while another had a permanent stent inserted for drainage. We conclude that ERCP and ES are useful and safe modalities in the assessment of biliary tract diseases and the treatment of choledocholithiasis.

Low-dose cimetidine in the acute treatment of duodenal ulcer. Comparison of a single nocturnal dose regimen with a twice daily regimen

A 0.5 g daily dose of cimetidine was as effective as a 1 g dose in the acute treatment of duodenal ulcer patients in Hong Kong. The aims of the present study were, first, to determine whether low-dose cimetidine treatment was as effective as standard doses in acute duodenal ulcer treatment of patients in Singapore, and second, to compare a single nocturnal dosage regimen with a twice daily regimen. In this single centre, double-blind, controlled trial, 282 patients with endoscopically proven duodenal ulcer were randomized to receive four weeks' treatment with cimetidine using one of three dosage regimens: (A) 800 mg at night; (B) 400 mg at night; or (C) 400 mg twice daily. Two hundred and forty-seven patients were evaluated. The incidences of healing at four weeks were: (A) 40/80 (50%), (B) 39/88 (44%); and (C) 48/79 (61%); (B vs C: P less than 0.05; A vs C: NS; 95% confidence limits: -5% to 27%; A vs B: NS, 95% confidence limits: -6% to 21%). Of 183 patients who had antral biopsies taken, 176 (96%) had histological gastritis, while 167 (91%) were positive for Helicobacter-like organisms. The occurrence of gastritis or Helicobacter-like organisms had no influence on ulcer healing. A 400 mg dose of cimetidine is therefore suboptimal for the treatment of duodenal ulcer in patients in Singapore. A single nocturnal dosage regimen may be less effective than a twice daily regimen.

Hepatitis B vaccination in chronic renal failure patients undergoing haemodialysis: the immunogenicity of an increased dose of a recombinant DNA hepatitis B vaccine

Thirty-two patients with end stage renal failure who were on haemodialysis and who had no previous exposure to hepatitis B virus were given four intramuscular injections of 40 micrograms (twice the recommended dose) recombinant DNA hepatitis B vaccine (Engerix B, Smith Kline Biologicals) at 0, 1, 2 and 6 months to determine the immunogenicity of this increased vaccine dose. The ages of these patients ranged from 23-54 years with a mean age of 40 years. There were 11 males and 21 females. Three patients underwent renal transplantation during the course of the study and were assessed separately. Antibody levels above 10 IU/L were noticed in 83% of the remaining 29 patients two months after the final dose with an anti-HBs geometric mean titre (GMT) of 2551 IU/L. The antibody response was 82% four months later although the GMT has fallen to 664 IU/L. Renal transplantation did not appear to affect the anti-HBs response to the above vaccination regime. None of the volunteers developed hepatitis B during the study. Our results were much better than results obtained in studies using twice the recommended doses given three times.