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Biomedical subjects

I R Wanless

Publications and source records attributed to I R Wanless.

At least 37 records · Page 2Linked to original sources
PubMed1996

The hepatic von Meyenburg complex: prevalence and association with hepatic and renal cysts among 2843 autopsies [corrected].

von Meyenburg complexes (VMC) are dilated small bile ducts surrounded by fibrous stroma. These lesions are frequently seen at autopsy, especially in association with polycystic disease of the kidney and/or liver. The purpose of this study was to quantitate the prevalence of VMC and associated lesions, with a view to clarifying the nature of VMC. We examined the liver slides from 2843 autopsies and found 157 patients having VMC or cysts in the liver. For each of the 157 patients, and age- and gender-matched controls, VMC, hepatic cysts, and gross and microscopic renal cysts were counted and measured and autopsy reports were reviewed. VMC were found in 5.6% of adults and in 0.9% of children. Macroscopic hepatic cysts were found in 16.9% of livers that also had VMC. Of livers with hepatic cysts, 73.5% also had VMC. Adult polycystic kidney disease (APKD) was found in 11% of adults with at least one VMC and in 40% of those with four or more VMC. Among adults with APKD, VMC were found in 97% and hepatic cysts in 88%. Because APKD could account for only 11% of the patients with VMC, we suggest that VMC, in the absence of APKD, are a manifestation of a different disease, which could be genetic or secondary to inflammation or ischemia.

Adolescent↗
PubMed1996

Noncirrhotic portal hypertension: recent concepts.

NCPH is a result of obliteration of portal veins. Many inflammatory conditions may initiate the process by causing endothelial injury. As obliteration progresses, there is local stasis and low-grade portal hypertension. In many cases, superimposed PVT occurs before portal hypertension becomes clinically evident. Hypercoagulability is an important cofactor. Diagnosis requires the exclusion of cirrhosis. Focal atrophy and nodular hyperplasia on biopsy may be a clue to the presence of small vessel obliteration. The distribution of vascular disease should be documented with Doppler ultrasound of both portal and hepatic veins. Investigation of cause should include tests for myeloproliferative and other hypercoagulable disorders, systemic diseases associated with vascular injury (eg, autoimmune diseases and toxin exposure) and local portal tract inflammatory diseases (primary biliary cirrhosis and sarcoidosis). Advances in this field will likely be made with improved diagnosis of acute and recanalized PVT using MRI, the new Acuson Sequoia ultrasound technology, and intravascular ultrasonography. Advances in the cause of PVT await studies using new and improved tests for the diagnosis of hypercoagulable states.

Humans↗
PubMed1995

Interferon alfa treatment of chronic hepatitis B: randomized trial in a predominantly homosexual male population.

BACKGROUND/AIMS: It has been suggested that human immunodeficiency virus (HIV) coinfection and male homosexuality predict poor response to interferon alfa therapy of chronic hepatitis B. The aim of this study was to examine the effect of HIV coinfection on the response of chronic hepatitis B virus (HBV) infection to interferon alfa therapy in a predominantly homosexual male population. METHODS: Fifty patients (82% male homosexuals, 50% HIV positive) with evidence of chronic HBV infection were randomized, stratified by HIV status, to undergo either treatment with interferon alfa (10 MU/m2 three times weekly for 12 weeks) or no treatment. Response was predefined as loss of serum HBV DNA, loss of hepatitis B e antigen, and the appearance of antibody to hepatitis B e antigen. HIV status and the interferon alfa-associated enzyme, 2',5'-oligoadenylate synthetase, were evaluated as potential predictors of response to therapy. RESULTS: Six treated patients responded with development of antibodies to hepatitis B e antigen (P < 0.05). HIV-positive patients were about one-fifth as likely to respond to interferon alfa therapy (relative risk, 0.22; 95% confidence interval, 0.03-1.78). Pretreatment alanine aminotransferase levels were significantly higher in responders than in nonresponders (P = 0.0005). Pretreatment 2',5'-oligoadenylate synthetase levels did not predict response. CONCLUSIONS: Interferon alfa, 10 MU/m2 three times weekly for 12 weeks, is effective in eradicating HBV replication in a predominantly homosexual male population not coinfected with HIV.

2',5'-Oligoadenylate Synthetase↗
PubMed1995

Hepatotoxicity: newer aspects of pathogenesis and treatment.

The etiology and the pathogenesis of different forms of hepatotoxicity are discussed; case reports are included to illustrate the importance of history-taking and examination of liver tissue in establishing a specific diagnosis. The role of alcohol as a hepatotoxin as well as an enzyme-inducing agent is stressed. Genetic factors have been identified that may determine susceptibility to alcoholism and the hepatotoxic effects of alcohol and other compounds. Some cases of drug-induced cholestasis may be explained by disturbances in the known pathways of bile acid uptake, transport, and excretion. The importance of small duct destruction in patients with progressive drug-induced cholestasis is discussed. Finally, the potential hepatic complications of some nonprescription remedies used by adherents of "alternative medicine" are described, emphasizing the relevance of thorough etiological inquiry in all patients presenting with hepatic dysfunction.

Acetaminophen↗
PubMed1995

Progressive type of focal nodular hyperplasia characterized by multiple tumors and recurrence.

Focal nodular hyperplasia (FNH) is usually a stable lesion that does not enlarge when studied for long periods of time; recurrence after resection has not been reported. We present a patient with a solitary FNH lesion that enlarged, was resected, and then recurred. A second resection was performed because of abdominal pain and disclosed multiple lesions, two of which were acutely infarcted. Thirty-two months later there was ultrasound evidence of further recurrence. Histology of the lesions showed the usual appearance of FNH with ducts and ductules in the central stalk regions but also some areas with minimal ductular differentiation and scanty connective tissue. Because of the clinical and histological appearance, the lesions in this patient were distinct from the usual type of FNH and merit the name "focal nodular hyperplasia, progressive type."

Adult↗
PubMed1995

Chaparral-induced hepatic injury.

Two patients with hepatic injury after ingestion of chaparral leaf are presented. The first patient, a 71-yr-old man, developed biopsy-proven hepatitis 3 months after ingesting chaparral leaf daily. His illness resolved with discontinuation of the herb and later recurred with rechallenge. The second patient is a 42-yr-old woman who developed hepatitis 2 months after chaparral leaf ingestion and recovered completely after discontinuation of the compound. Both patients have remained well with abstinence from chaparral. These reports provide evidence of the hepatotoxicity of this herb and stress the need for awareness of the potential harm from such nonprescription remedies.

Adult↗
PubMed1995

Role of thrombosis in the pathogenesis of congestive hepatic fibrosis (cardiac cirrhosis).

The pathogenesis of congestive cirrhosis is generally thought to be a reaction of the hepatic stroma to hypoxia, pressure, or necrosis. This does not explain the poor correlation between symptoms and severity of fibrosis and the irregular distribution of fibrosis within the liver. We have observed healed hepatic vein (HV) thrombosis in patients with congestive heart failure (CHF). The purposes of this study were to document hepatic vascular lesions in autopsy livers of patients with chronic CHF, to determine the role of these lesions in the pathogenesis of congestive cirrhosis, and to refine the definition of congestive cirrhosis. Twenty-five livers were studied, 13 with multiple large blocks 4 x 5 cm. Sections were graded for parenchymal fibrous septa, sinusoidal fibrosis, and intimal fibrosis of portal veins (PVs) and HVs. Fibrous septa were found in livers of 7 of 13 patients with CHF and in none of 12 controls without CHF (P = .007). Parenchymal fibrosis was highly variable in distribution, often with severe septation in some areas and nearly normal morphology in others. Intimal fibrosis and obstruction of small- and medium-HVs were found only in livers of patients with CHF. The vascular lesions were confined to regions with fibrous septation and had morphology suggestive of organized thrombosis. Acute thrombi in sinusoids were noted in livers of 4 patients with CHF and in livers of 2 patients without CHF. These findings support the hypothesis that congestive cirrhosis is a response to intrahepatic thrombosis. The pattern of disease suggests that thrombus begins in sinusoids, occasionally propagates to HVs, and causes secondary local PV thrombosis, ischemia, parenchymal extinction, and fibrosis.

Aged↗
PubMed1995

Hepatic and portal vein thrombosis in cirrhosis: possible role in development of parenchymal extinction and portal hypertension.

Obliterative lesions in portal veins (PVs) and hepatic veins (HVs) of all sizes are known to occur in cirrhotic livers. PV lesions have generally been attributed to thrombosis, but the pathogenesis of the HV (veno-occlusive) lesions is unknown. We have studied 61 cirrhotic livers removed at transplantation to clarify the prevalence, distribution, and pathogenesis of venous lesions, as well as the association of these lesions with other morphological features and clinical morbidity. Intimal fibrosis that is highly suggestive of healed HV or PV thrombosis was found in at least 70% and 36% of livers, respectively. The distribution of HV lesions was patchy and largely confined to veins between 0.1 and 3 mm in diameter, suggesting multifocal origin in small veins. PV lesions were more uniform throughout the liver, suggesting origin in large veins with propagation to the small veins. HV lesions were associated with regions of confluent fibrosis (focal parenchymal extinction), and PV lesions were associated with regional variation in the size of cirrhotic nodules and a history of bleeding varices. These observations suggest that thrombosis of medium and large PVs and HVs is a frequent occurrence in cirrhosis, and that these events are important in causing progression of cirrhosis.

Budd-Chiari Syndrome↗
PubMed1995

Intrahepatic sequestered segment of liver presenting as focal fatty change.

Focal fatty change of the liver is a lesion that is often discovered on imaging studies and must be distinguished from space-occupying lesions. The pathogenesis is unknown. We report a lesion of focal fatty change in which the portal supply and biliary drainage were anomalous so that the lesion represents sequestered liver tissue. Because insulin favors the development of steatosis, the pathogenesis of focal fatty change could be explained if the aberrant portal supply contained more insulin than the main portal vein, as would occur if the portal supply arose from pancreatic veins via the parabiliary venous plexus of Couinaud. Furthermore, focal fatty sparing could be explained if the spared segment was supplied by veins draining from the stomach that carry blood with lower insulin levels than the main portal vein.

Adult↗
PubMed1994

Acute hepatitis associated with the Chinese herbal product jin bu huan.

OBJECTIVE: To describe the hepatotoxicity associated with ingestion of the Chinese herbal product Jin Bu Huan Anodyne Tablets (Lycopodium, serratum) and to propose possible mechanisms of injury. DESIGN: Retrospective analysis. SETTING: Academic hepatology units and private practice facilities. PATIENTS: Seven previously healthy patients. MEASUREMENTS: Clinical, laboratory, radiologic, and histologic studies. RESULTS: Acute hepatitis occurred after a mean of 20 weeks (range, 7 to 52 weeks) of Jin Bu Huan ingestion and resolved in six patients within a mean of 8 weeks (range, 2 to 30 weeks); another patient is currently improving. Hepatitis was associated with symptoms of fever, fatigue, nausea, pruritus, and abdominal pain and with signs of jaundice and hepatomegaly. Biopsy specimens showed that one patient had hepatitis with eosinophils (consistent with a drug reaction) and the other had mild hepatitis, moderate fibrosis, and microvesicular steatosis. Decreasing the Jin Bu Huan dose in one patient improved liver test results. Reusing Jin Bu Huan in two other patients caused abrupt recrudescence of hepatitis. CONCLUSION: Jin Bu Huan can cause liver injury. Although the hepatotoxic mechanisms are not defined, they may include hypersensitive or idiosyncratic reactions or direct toxicity to active metabolites. Hepatotoxicity caused by herbal products underscores the toxicity caused by herbal products underscores the importance of national surveillance programs and quality control of the manufacture of these products.

Acute Disease↗
PubMed1994

Antimitochondrial antibody negative primary biliary cirrhosis: a distinct syndrome of autoimmune cholangitis.

This study reports on a group of 20 patients with an initial diagnosis of primary biliary cirrhosis (PBC) whose serum tested negative for antimitochondrial antibodies by immunofluorescence. All had a clinical history compatible with primary biliary cirrhosis, and results of biochemical, histological, and radiological investigations were consistent with this diagnosis despite the absence of antimitochondrial antibodies by immunofluorescence. For comparison, these patients were matched for sex and serum bilirubin with 20 antimitochondrial antibody positive (> 1:160) and histologically confirmed primary biliary cirrhosis patients who served as controls. Serum samples from both groups were retested blindly for antimitochondrial antibodies using immunoblotting and for antibodies to the major M2 mitochondrial autoantigens by enzyme linked immunosorbent assay (ELISA). Three antimitochondrial antibody immunofluorescence negative patients had antimitochondrial antibodies by immunoblotting and ELISA; the remaining 17 patients were confirmed negative by all methods. The antimitochondrial antibody immunofluorescence positive controls were verified by immunoblotting or ELISA, or both. All 17 patients negative for antimitochondrial antibodies had antinuclear antibodies, often in high titres, compared with 3/17 of the antimitochondrial antibody positive controls (p = 0.0001). Additionally, the antimitochondrial antibody negative group also had significantly higher smooth muscle antibody titres (p = 0.03) and lower serum IgM (p = 0.01) and aspartate aminotransferase (p = 0.03) activities than the antimitochondrial antibody positive controls. Analysis of clinical findings, histological tests, serum bilirubin, alkaline phosphatase, alanine aminotransferase, and IgG, disclosed no significant differences between the two groups. This paper describes a group of patients with the clinical and histological features of PBC but who do not fulfil the usual criteria necessary to make this diagnosis. Because they also have very high titres of antinuclear antibodies, smooth muscle antibodies, and comparatively low IgM and aspartate aminotransferase activities, we believe they are distinct from PBC and have a syndrome of autoimmune cholangitis.

Adult↗
PubMed1994

Cholestatic liver disease with ductopenia (vanishing bile duct syndrome) after administration of clindamycin and trimethoprim-sulfamethoxazole.

Two patients who developed cholestatic liver disease after exposure to antibiotics are described. One patient who received clindamycin had liver biopsy findings of marked cholestasis, portal inflammation, bile duct injury and bile duct paucity (ductopenia). A second biopsy after clinical improvement showed resolution of cholestasis but persistence of duct paucity. Three years later, treatment with ampicillin caused another episode of cholestatic hepatitis with cholestasis and duct paucity on rebiopsy. The second patient, who developed cholestasis after receiving trimethoprim-sulfamethoxazole, had marked duct paucity in the liver biopsy. This is the first description, to our knowledge, of ductopenia apparently caused by clindamycin. Cross-reactivity between clindamycin and ampicillin is also demonstrated in one patient. This report documents that duct paucity may occur within 10 days of onset of jaundice and appears to be confined to ducts less than 0.03 mm in diameter.

Abscess↗
PubMed1993

The vascular pathology of human hepatic allografts.

Studies of hepatic transplant vasculopathy (TV) have described arterial lesions in selected cases but have not sought to establish the relative prevalence of various arterial and venous lesions. We examined 20 unselected liver allografts and 12 controls to establish the spectrum and distribution of transplant-related arterial and venous lesions. Sections of 1,175 arteries and 936 portal and hepatic veins were reviewed and several histologic parameters were tabulated. Fibrotic (18 cases: 184 arteries and 17 veins) and cellular (10 cases: 353 arteries and 33 veins) lesions were seen. Three allografts had evidence of severe TV with abundant foam cell, myointimal, and mixed fibrocellular lesions in the intima of arteries. These three grafts also had foam cells in portal veins. Allografts with TV had more stenotic arteries (P < .05) and more intimal cellular proliferation (P < .05) compared with non-TV allografts and with controls. Foam cells often demonstrated immunoperoxidase staining for actin, lysozyme, or UCHL-1. Two of the TV cases had marked paucity of bile ducts and required retransplantation.

Adult↗
PubMed1993

The role of transjugular liver biopsy in fulminant liver failure: relation to other prognostic indicators.

Early and accurate diagnosis and prognosis of patients with fulminant liver failure is of critical importance for optimum management. We investigated the role of transjugular liver biopsy in the management of patients with fulminant liver failure and assessed its value in comparison with the recently proposed King's College criteria. Sixty-one patients with fulminant liver failure, ages 2 to 82 yr, were retrospectively analyzed. The main outcome measures were survival vs. death or progression to orthotopic liver transplantation. Transjugular liver biopsy was successful in 60 of 61 patients, with a mean core tissue length of 2.1 cm. There were eight minor complications, all of which were managed conservatively. Biopsy specimens were evaluated for degree of fibrosis, percentage of hepatocellular necrosis and presence of bile duct proliferation, hepatocellular mitotic figures and binucleate hepatocytes for each of the 54 specimens available for analysis. In 34 of 54 patients (63%), the presumed clinical diagnosis was confirmed by transjugular liver biopsy. In 11 patients the procedure served to clarify clinical uncertainty, whereas in 9 of 54 (16.7%) the diagnosis was altered after transjugular liver biopsy. The percentage of necrosis was the only histological parameter that appeared to have significant discriminatory prognostic value, with only 2 of 19 survivors having greater than 70% necrosis. Twenty-one of these biopsy specimens were reviewed by two pathologists, and their degree of correlation for the various features was assessed. Almost perfect concordance was found between the two pathologists on the percentage of hepatocellular necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaminophen↗
PubMed1990

Micronodular transformation (nodular regenerative hyperplasia) of the liver: a report of 64 cases among 2,500 autopsies and a new classification of benign hepatocellular nodules.

Nodular regenerative hyperplasia is defined by hepatocellular nodules distributed throughout the liver in the absence of fibrous septa between the nodules. Most reports have been single cases so that the prevalence and clinical significance of nodular regenerative hyperplasia is uncertain. In this study, the hepatic histology of 2,500 consecutive autopsies was reviewed. A spectrum of nodular transformation was found with nodular regenerative hyperplasia present in 2.6% of autopsy livers and qualitatively similar but lesser degrees of nodular transformation in a further 10.2%. Nodular transformation was also seen in 47% of livers with cirrhosis and 69% with incomplete cirrhosis. Obliteration of many small portal veins was seen in all cases with nodular regenerative hyperplasia, but only 4.7% of these had evidence of portal hypertension. The prevalence of various clinical states was compared in nodular regenerative hyperplasia and in controls. The results confirm, extend and quantify the spectrum of associated diseases. Nodular regenerative hyperplasia occurs in 5.6% of individuals over age 80 and with increased frequency in patients with systemic arteritis, polymyalgia rheumatica, massive tumor infiltration and mineral oil deposition. Nodular regenerative hyperplasia appears to be the hepatic analogue of arterial and arteriolar nephrosclerosis. A new classification of nodular transformation is proposed that encompasses the spectrum of lesions described here and the previously defined entities of focal nodular hyperplasia, partial nodular transformation and "cirrhosis telangiectasia hepatis." The major conclusion is that nodular regenerative hyperplasia is a secondary and nonspecific tissue adaptation to heterogeneous distribution of blood flow and does not represent a specific entity.

Aged↗
PubMed1990

The demography of primary biliary cirrhosis in Ontario, Canada.

The demographics of primary biliary cirrhosis in Ontario, Canada, are described. Two hundred and twenty-five primary biliary cirrhosis patients were identified by 85 of 502 gastroenterologists (or internists) practicing in Ontario acute care hospitals that have 150 or more beds. Two hundred and six patients were verified as being antimitochondrial antibody-positive, resulting in an incidence of 3.26 per million per year and a prevalence of 22.39 per million. Questionnaire data were obtained on 88.5% of these patients. Twenty-nine percent of the patients were found to be asymptomatic. Geographical clustering and racial predisposition were not seen. No increase in breast cancer prevalence was noted. By the time the diagnosis of primary biliary cirrhosis was established, the patients had consulted a median number of 3.5 physicians. Fatigue was reported as the most disabling symptom. The diagnosis of primary biliary cirrhosis in patients referred from across the province of Ontario was independently confirmed by us, using standard criteria (antimitochondrial antibody testing and liver biopsy), and was found to be reliable.

Autoantibodies↗
PubMed1990

Fatty liver hepatitis (steatohepatitis) and obesity: an autopsy study with analysis of risk factors.

Steatohepatitis (fatty liver hepatitis), histologically identical to alcoholic disease, occurs in some obese patients after jejunoileal bypass. A similar lesion occurs rarely in obese patients without bypass surgery, but the risk factors are poorly understood. Hepatic steatosis, steatohepatitis and fibrosis were sought in 351 apparently nonalcoholic patients at autopsy and various risk factors were evaluated. Incidence of steatosis and steatohepatitis correlated with the degree of obesity. Steatohepatitis was found in 18.5% of markedly obese patients and 2.7% of lean patients. Additional risk factors for steatohepatitis were type II diabetes, weight loss in the preterminal period shortly before death and intravenous glucose therapy in the last week of life. Severe fibrosis was found in 13.8% of markedly obese patients and in 6.6% of lean patients; this difference was largely explained by the higher prevalence of diabetes in obese groups. The risk factors defined in this study are known to be associated with abnormalities of free fatty acid metabolism. Obesity, type II diabetes and intravenous glucose therapy are associated with hyperinsulinemia, which may inhibit fatty acid oxidation. Obesity and weight loss increase the presentation of fatty acids to the liver. Similar metabolic changes may occur in obese patients after jejunoileal bypass surgery. Thus this study supports the hypothesis that fatty acids have a role in the hepatocellular necrosis found in some obese individuals.

Autopsy↗