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S H Caldwell

Publications and source records attributed to S H Caldwell.

At least 19 recordsLinked to original sources

Myositis, microvesicular hepatitis, and progression to cirrhosis from troglitazone added to simvastatin.

A 68-year-old woman, with type 2 diabetes mellitus, hypercholesterolemia, and prior long-term simvastatin therapy, self-resumed troglitazone after running out of metformin. She developed an acute severe hepatitis with microvesicular steatosis and mysositis. There was subsequent resolution of the myositis but progression of the hepatitis to symptomatic cirrhosis over a period of 12 weeks. Both troglitazone and simvastatin are metabolized by cytochrome P-450 3A4. Troglitazone typically induces metabolism of drugs metabolized by this cytochrome so that simple simvastatin toxicity seems less likely to have been involved. The association with myositis, the severity of the hepatitis with progression to cirrhosis, and the presence of microvesicular steatosis suggests altered mitochondrial metabolism, which has been described with each agent, as the underlying pathogenic mechanism. Although troglitazone (Rezulin) has been withdrawn from the market, other similar agents are available for therapy of type 2 diabetes mellitus. Increased awareness of a potential interaction between these two classes of drugs is warranted.

Aged↗

Imaging and clinical characteristics of focal atrophy of segments 2 and 3 in primary sclerosing cholangitis.

BACKGROUND AND AIMS: Focal atrophy in primary sclerosing cholangitis (PSC) is usually thought to result from severe biliary stricture and focal biliary cirrhosis. Atrophy of the left lateral segments (segments 2 and 3) are striking when observed grossly. This type of atrophy may be subtle on cross-sectional imaging and by endoscopic retrograde cholangiopancreatography (ERCP) because of the peripheral location and compensatory hypertrophy of other parts of the liver. We examined 44 consecutive PSC patients to determine the incidence and clinical characteristics of this abnormality, and to correlate imaging studies with the gross appearance. METHODS: We reviewed all cases of PSC encountered over a 3 year period ascertained from the liver disease registry. Magnetic resonance imaging or CT images were re-examined for evidence of segment 2 and 3 atrophy. RESULTS: Four of 44 patients had focal segment 2 and 3 atrophy. These four had been confirmed laparoscopically or by inspection of the liver explant. The remaining segments of the liver were relatively spared of injury in two of the patients, and three of the four patients had preserved synthetic function without evidence of portal hypertension. While the abnormality is clearly visible on cross-sectional imaging, its peripheral location caused it to be an unobtrusive. Likewise, ERCP did not clearly reveal the abnormality on initial inspection. CONCLUSIONS: We conclude that focal atrophy of segments 2 and 3 is a sometimes early and subtle finding in PSC that may be overlooked in cross-sectional imaging or ERCP unless specifically sought.

Adult↗

A pilot study of a thiazolidinedione, troglitazone, in nonalcoholic steatohepatitis.

OBJECTIVES: Troglitazone is a thiazolidinedione and peroxisome proliferator-activated receptor gamma (PPARgamma) ligand used to treat diabetes mellitus type II. Because hyperinsulinemia may be a factor in nonalcoholic steatohepatitis (NASH), we postulated that troglitazone could have beneficial effects in this disorder. Our study was initiated before reports of idiosyncratic hepatitis induced by this agent and was completed before its recent withdrawal from the market. METHODS: We studied 10 female patients (age 44 +/- 16) with histological NASH. All but two were obese (mean body mass index, BMI = 38 +/- 6). One had type 2 diabetes, and three had well-compensated cirrhosis with NASH. Troglitazone was given at a dose of 400 mg/day for < or = 6 months. Responders (defined as normal ALT at the end of treatment) were rebiopsied. Paired specimens were compared in blinded fashion. Mitochondria were quantitated using ultrathin electron microscopy. RESULTS: Seven of ten patients responded with normal ALT at the end of treatment. One of three nonresponders initially normalized ALT but returned to pretreatment level at 3 months. In this patient, therapy was stopped, and the ALT has remained at the baseline level with no other clinical or laboratory findings. In the responders, ALT fell from 87 +/- 38 before to 39 +/- 9 at the end of treatment (p = 0.01), and AST decreased from 77 +/- 23 to 30 +/- 8 (p = 0.002). Biopsy comparisons before and after therapy showed persistent steatohepatitis in all cases, although four of seven showed a one-point improvement in the necroinflammatory grade. Electron microscopy revealed elongation of the mitochondria after therapy. CONCLUSIONS: Normal ALT was seen in 70% of NASH patients at the end of treatment, but this biochemical response was associated with only mild histological improvement, and all follow-up biopsies had evidence of NASH. Normalization of the liver enzymes in patients with NASH who are treated with thiazolidinediones should be viewed with reservation. Follow-up biopsy is essential to evaluate the efficacy of these agents, which, at the histological level, appears to be relatively modest.

Adult↗

Nonalcoholic steatohepatitis and cryptogenic cirrhosis within kindreds.

PURPOSE: Familial forms of cryptogenic cirrhosis have been described. We have cared for families in which several members were afflicted with cryptogenic cirrhosis as well as the more recently recognized entity of nonalcoholic steatohepatitis. To examine the familial patterns of these disorders, we reviewed patients with nonalcoholic steatohepatitis, with and without cirrhosis, or cryptogenic cirrhosis to assess how frequently their relatives were afflicted with these disorders. SUBJECTS AND METHODS: Eighteen members of eight kindreds containing 2 or more afflicted members were studied. Diagnoses were based on histology in all but 3 patients (2 elderly women with liver atrophy and severe cirrhotic ascites diagnosed clinically with cryptogenic cirrhosis and 1 adult man with abnormal serum aminotransferase levels and hepatomegaly that was diagnosed as fatty liver by ultrasound). Other forms of liver disease were excluded by extensive serologic testing. RESULTS: There were 8 index patients (1 man, 7 women; 2 with cryptogenic cirrhosis, 4 with nonalcoholic steatohepatitis with cirrhosis, and 2 with nonalcoholic steatohepatitis without cirrhosis) and 10 relatives (4 men, 6 women; 2 with cryptogenic cirrhosis and 8 with nonalcoholic steatohepatitis). Nonalcoholic steatohepatitis and nonalcoholic steatohepatitis with cirrhosis coexisted within four kindreds, one of which also had an afflicted member with cryptogenic cirrhosis. Nonalcoholic steatohepatitis and cryptogenic cirrhosis coexisted within three additional kindreds. Patterns of afflicted patients included mother-daughter, sister-sister, sister-brother, father-daughter, and male-female cousins. Fifteen (83%) of the 18 subjects were obese, and 11 (61%) had type 2 diabetes mellitus. CONCLUSIONS: The coexistence of nonalcoholic steatohepatitis with and without cirrhosis and cryptogenic cirrhosis within these kindreds suggests a common pathogenesis and possible genetic risk. These disorders were frequently but not invariably associated with female sex, obesity, and type 2 diabetes.

Adult↗

Cryptogenic cirrhosis: clinical characterization and risk factors for underlying disease.

We characterized 70 consecutive patients with cryptogenic cirrhosis to assess major risks for liver disease. Each patient was reevaluated for past alcohol exposure, scored by the International Autoimmune Hepatitis (IAH) score and assessed for viral hepatitis risks and risks for nonalcoholic steatohepatitis (NASH). The results were compared with 50 consecutive NASH patients, 39 nonalcoholic patients age 50 and over with cirrhosis from hepatitis C, and 33 consecutive patients with cirrhosis caused by primary biliary cirrhosis (PBC). Among the cryptogenic group, 49 (70%) were female, and the mean age was 63 +/- 11 years. Although ascites and variceal bleeding were common, almost one half lacked major signs of complicated portal hypertension. A history of Type 2 diabetes mellitus and/or obesity was present in 51 (73%). Nineteen (27%) patients had a history of blood transfusions antedating the diagnosis of cirrhosis. No clinical or histological features distinguished this group from the other patients, and 14 (74%) of these had a history of obesity and/or diabetes. Nineteen of the remaining nontransfused patients had indeterminant IAH scores but were histologically and biochemically indistinguishable from the others. Twelve of these (63%) also had a history of obesity and/or diabetes. Both diabetes and obesity were significantly more common in the cryptogenic cirrhotic patients compared with the cirrhotic patients with PBC or hepatitis C. In contrast, the prevalence of obesity and diabetes was similar to the NASH patients who were, on average, a decade younger. Although there is some diversity that indicates more than one cause, our findings suggest that NASH plays an under-recognized role in many patients with cryptogenic cirrhosis, most of whom are older, type 2 diabetic and obese females.

Adult↗

Mitochondrial abnormalities in non-alcoholic steatohepatitis.

BACKGROUND/AIMS: We assessed mitochondrial morphology by electron microscopy and the prevalence of a mitochondrial gene deletion in patients with non-alcoholic steatohepatitis (NASH), alcohol-related liver disease and non-fatty liver diseases. Respiratory chain function using a cytoplasmic hybrid (cybrid) assay was further studied in NASH patients and healthy controls. METHODS: Electron microscopy was performed in 26 specimens. Fifteen patients were studied by polymerase chain reaction to detect a 520-bp deletion product of the mitochondrial genome (dmtDNA). Cybrids were created by fusion of platelets with anaerobic neuroblastoma cells in six NASH patients and 12 controls. RESULTS: Eight of ten NASH, one of seven alcoholics and two of nine other patients had linear crystalline inclusions in megamitochondria (p<0.05). Three of five patients with alcohol-related liver disease had dmtDNA compared to one of five NASH patients and one of five non-steatohepatitis controls. Cybrid respiratory chain function in platelets was not different from that of controls. CONCLUSIONS: Respiratory chain dysfunction, if present in NASH, is not expressed in platelet-derived mitochondria. In contrast to alcohol-related liver disease with active drinking, NASH patients do not commonly express the 5-kb mitochondrial DNA gene deletion in liver tissue. As previously described in early alcohol-related liver disease, crystalline inclusions of unknown composition are seen in hepatic mitochondria in NASH. Their presence suggests either an adaptive process or mitochondrial injury.

Adult↗

Use of fibrin sealant to reduce bleeding after needle liver biopsy in an anticoagulated canine model: work in progress.

PURPOSE: Needle biopsy of the liver is a common diagnostic procedure. Although relatively safe, bleeding remains a potential complication and may occur more frequently in patients with coagulopathy. The purpose of this study was to evaluate the utility of a fibrin sealant in preventing bleeding after a 15-gauge needle biopsy of the liver in a canine model heparinized to simulate coagulopathy. MATERIALS AND METHODS: Fibrin sealant was delivered to biopsy tract sites in eight dogs anticoagulated with heparin (activated clotting time 387 seconds +/- 94) using the same sheath system that was employed to obtain the biopsy specimen. RESULTS: The results demonstrated complete hemostasis in the sealant-plugged tracts as compared to controls. Continuous bleeding was observed in none of the fibrin sealant-treated sites, compared with all of the control biopsy sites (P = .0078). CONCLUSION: These results demonstrate the high degree of efficacy of fibrin sealant delivered through a sheath system in plugging liver biopsy tracts and eliminating bleeding in a severely coagulopathic animal model. This indicates that fibrin sealant use in cutting needle biopsies can reduce major and minor complications associated with the procedure.

Animals↗

Gastric myoelectric activity in patients with end-stage liver disease.

BACKGROUND: Abnormalities of gastrointestinal motility and transit time have been reported in association with end-stage liver disease. Motility abnormalities could be routinely studied if a simple noninvasive test were available. The electrogastrogram is a cutaneous measure of gastric myoelectric activity and correlates well with serosal recordings of gastric myoelectric activity. The aim of this study was to evaluate gastric myoelectric activity in patients with end-stage liver disease. METHODS: Fourteen patients with end-stage liver disease had gastric myoelectric activity measured with the electrogastrogram. An electrogastrogram was considered abnormal when normal gastric slow waves were seen less than 70% of the time or there was no increase in the electrogastrogram amplitude after a meal. RESULTS: Abnormal electrogastrograms were present in 8 of 14 (57%) end-stage liver disease patients. CONCLUSIONS: Abnormal gastric myoelectric activity is common in end-stage liver disease.

Adult↗

Subumbilical midline vascularity of the abdominal wall in portal hypertension observed at laparoscopy.

BACKGROUND: Large volume paracentesis is a common treatment of ascites. Injury to abdominal wall collateral veins during this procedure can lead to hemoperitoneum. Because of this concern, the midline below the umbilicus is often recommended as a site for paracentesis because of its presumed avascularity. METHODS: We examined the subumbilical peritoneal surface in 20 consecutive patients with liver disease undergoing diagnostic laparoscopy. This area was visualized by table tilting and confirmed by external finger compression. Nineteen patients had cirrhosis of various etiologies, and one had advanced fibrosis with evidence of portal hypertension. RESULTS: In these 20 patients, only 7 had avascular midlines below the umbilicus. Seven had small but definite veins running along the path of the urachus (median umbilical fold), and 6 had more prominent veins in this region. The internal landmarks in this region (median and medial folds) were frequently asymmetric with regard to the external appearance of the midline. CONCLUSION: The subumbilical midline in patients with portal hypertension is commonly vascular. When using this site for paracentesis, care should be exercised to identify venous structures with the narrow-gauge needle used to inject local anesthetic agent before placement of larger paracentesis needles.

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