PubMed Health⌕ Search

Biomedical subjects

K V Kowdley

Publications and source records attributed to K V Kowdley.

At least 37 records · Page 2Linked to original sources
PubMed1999

Cognitive impairment and intracranial calcification in chronic hypoparathyroidism.

BACKGROUND: Intracranial calcification is associated with chronic hypoparathyroidism. The relationship between intracranial calcification, neurological abnormalities and cognitive deficits in this disorder is unknown. The purpose of this study was to determine whether chronic hypoparathyroidism is associated with cognitive impairment. METHODS: We studied 11 hypoparathyroid patients and compared them with a sex-, age-, and education-matched control group. The hypoparathyroidism was postsurgical in nine and idiopathic in two. All patients underwent nonenhanced head computed tomography, detailed neurological examinations, and a battery of cognitive tests. These tests were performed separately and individual examiners were blinded to the results of the other components of the study. RESULTS: The mean age of the patients was 55 years; the duration of hypoparathyroidism was at least 9 years. Neuropsychological testing revealed cognitive impairment in 65% of hypoparathyroid subjects, and the presence of significant differences between the hypoparathyroid and control groups. Computed tomography showed intracranial calcification in 6 of 10 hypoparathyroid subjects tested, and neurological (motor) examination revealed 5 of 11 with abnormal findings. There were positive correlations between the presence of cognitive deficits and cerebral calcification (r = 0.59, P = 0.07), between abnormal motor findings and cerebral calcification (r = 0.77, P < 0.01) and between abnormal motor findings and the degree of cognitive deficit (r = 0.83, P < 0.01). CONCLUSIONS: We conclude that cognitive and neurological deficits commonly occur in patients with chronic hypoparathyroidism and may be pathophysiologically related to the presence of intracranial calcification.

Adult↗
PubMed1999

Relationship between iron concentration and hepatitis C virus RNA level in liver tissue.

Patients with chronic hepatitis C virus (HCV) infection frequently have increased hepatic iron stores. The role of hepatitis C in hepatic iron deposition is unknown. The authors examined whether there is a relation between hepatitis C virus level in liver tissue and hepatic iron concentration. Forty-two paired samples obtained from the liver explants of five patients who underwent transplantation for liver disease due to hepatitis C were studied. Hepatitis C virus levels were measured at multiple sites within each liver by a branched deoxyribonucleic assay. Measurements of hepatic iron concentration were made at adjacent sites by a colorimetric assay. Random effects modeling showed wide intrahepatic variation in hepatic HCV ribonucleic acid (RNA) concentration (variance = 1.2 x 10(4) [mEq/g]2) and hepatic iron concentration (variance = 1.3 x 10(6) [microg/g]2). There was, however, a trend toward an association between the mean HCV level and the mean hepatic iron concentration for each liver (r = 0.30, p = 0.05). In conclusion, HCV level and iron concentration varied within and between cirrhotic livers. Variability in intrahepatic iron concentration was not related to variability in intrahepatic HCV RNA concentration. More studies are needed to determine the cause of variability in hepatic iron and HCV RNA concentration within and between livers in patients with chronic hepatitis C.

Hepacivirus↗
PubMed1999

Quantitative study of the variability of hepatic iron concentrations.

BACKGROUND: The hepatic iron concentration (HIC) is widely used in clinical practice and in research; however, data on the variability of HIC among biopsy sites are limited. One aim of the present study was to determine the variability of HIC within both healthy and cirrhotic livers. METHODS: Using colorimetric methods, we determined HIC in multiple large (microtome) and small (biopsy-sized) paraffin-embedded samples in 11 resected livers with end-stage cirrhosis. HIC was also measured in multiple fresh samples taken within 5 mm of each other ("local" samples) and taken at sites 3-5 cm apart ("remote" samples) from six livers with end-stage cirrhosis and two healthy autopsy livers. RESULTS: The within-organ SD of HIC was 13-1553 microg/g (CV, 3.6-55%) for microtome samples and 60-2851 microg/g (CV, 15-73%) for biopsy-sized samples. High variability of HIC was associated with mild to moderate iron overload, because the HIC SD increased with increasing mean HIC (P <0.002). Livers with mean HIC >1000 microg/g exhibited significant biological variability in HIC between sites separated by 3-5 cm (remote sites; P <0.05). The SD was larger for biopsy-sized samples than for microtome samples (P = 0.02). CONCLUSION: Ideally, multiple hepatic sites would be sampled to obtain a representative mean HIC.

Biopsy↗
PubMed1998

Diagnosis of hemochromatosis.

If untreated, hemochromatosis can cause serious illness and early death, but the disease is still substantially under-diagnosed. The cornerstone of screening and case detection is the measurement of serum transferrin saturation and the serum ferritin level. Once the diagnosis is suspected, physicians must use serum ferritin levels and hepatic iron stores on liver biopsy specimens to assess patients for the presence of iron overload. Liver biopsy is also used to establish the presence or absence of cirrhosis, which can affect prognosis and management. A DNA-based test for the HFE gene is commercially available, but its place in the diagnosis of hemochromatosis is still being evaluated. Currently, the most useful role for this test is in the detection of hemochromatosis in the family members of patients with a proven case of the disease. It is crucial to diagnose hemochromatosis before hepatic cirrhosis develops because phlebotomy therapy can avert serious chronic disease and can even lead to normal life expectancy.

Biopsy↗
PubMed1998

Management of hemochromatosis. Hemochromatosis Management Working Group.

The complications of iron overload in hemochromatosis can be avoided by early diagnosis and appropriate management. Therapeutic phlebotomy is used to remove excess iron and maintain low normal body iron stores, and it should be initiated in men with serum ferritin levels of 300 microg/L or more and in women with serum ferritin levels of 200 microg/L or more, regardless of the presence or absence of symptoms. Typically, therapeutic phlebotomy consists of 1) removal of 1 unit (450 to 500 mL) of blood weekly until the serum ferritin level is 10 to 20 microg/L and 2) maintenance of the serum ferritin level at 50 microg/L or less thereafter by periodic removal of blood. Hyperferritinemia attributable to iron overload is resolved by therapeutic phlebotomy. When applied before iron overload becomes severe, this treatment also prevents complications of iron overload, including hepatic cirrhosis, primary liver cancer, diabetes mellitus, hypogonadotrophic hypogonadism, joint disease, and cardiomyopathy. In patients with established iron overload disease, weakness, fatigue, increased hepatic enzyme concentrations, right upper quadrant pain, and hyperpigmentation are often substantially alleviated by therapeutic phlebotomy. Patients with liver disease, joint disease, diabetes mellitus and other endocrinopathic abnormalities, and cardiac abnormalities often require additional, specific management. Dietary management of hemochromatosis includes avoidance of medicinal iron, mineral supplements, excess vitamin C, and uncooked seafoods. This can reduce the rate of iron reaccumulation; reduce retention of nonferrous metals; and help reduce complications of liver disease, diabetes mellitus, and Vibrio infection. This comprehensive approach to the management of hemochromatosis can decrease the frequency and severity of iron overload, improve quality of life, and increase longevity.

Diet↗
PubMed1998

Public health surveillance for hereditary hemochromatosis.

The recent realization that hemochromatosis is a common condition has created opportunities to develop unified public health surveillance for this disorder and its complications and to design programs to prevent unnecessary illness and death resulting from this disorder. Public health surveillance for hemochromatosis can be used to measure the magnitude of the problem (for example, to establish the number of persons with evidence of early iron overload); identify research needs; reveal the natural history of the disease; detect changes in health care practices, such as use of screening tests; and evaluate interventions, such as phlebotomy. Existing surveillance has been limited to periodic measurement of morbidity and mortality done by using hospital discharge records, health examination surveys, vital statistics, and data from small research registries. The improvement of surveillance will entail the ongoing collection of information from population-based surveys, such as the Behavioral Risk Factor Surveillance System; the collection of data on provider practices (for example, through the National Ambulatory Medical Care Survey); and the establishment of population-based registries. Creating population-based registries requires consensus on case definitions; strategies to encourage case ascertainment and reporting; policies and procedures for protecting privacy and ensuring confidentiality; and partnerships among providers, researchers, and public health officials. Longitudinal data from population-based registries will provide insight into determinants of disease expression, such as pattern or degree of iron overload. This information is critical for developing evidence-based recommendations for population screening, monitoring changes in medical practices, and assessing the effect of preventive measures.

Confidentiality↗
PubMed1998

Successful treatment of severe hepatitis C-associated pulmonary vasculitis in a liver transplant recipient.

BACKGROUND: We report the clinical course of a patient who developed fever, hypoxia, and bilateral pulmonary infiltrates two and a half years after orthotopic liver transplantation (OLT) for cirrhosis due to hepatitis C. The patient had a history of hepatitis C-associated vasculitis manifested by purpuric skin rashes, renal abnormalities, and elevated cryoglobulins, and was receiving interferon-alpha at the time of presentation. RESULTS: The results of bronchoscopy with bronchoalveolar lavage were unrevealing, and open lung biopsy revealed active small vessel vasculitis. The patient responded dramatically to plasmapheresis and the addition of high-dose corticosteroids with resolution of hypoxia, pulmonary infiltrates, and glomerulonephritis. This is, to our knowledge, the first report of the successful treatment of hepatitis C-associated pulmonary vasculitis after OLT. CONCLUSIONS: We conclude that hepatitis C-associated pulmonary vasculitis should be included in the differential diagnosis of a patient presenting with fever, hypoxia, and pulmonary infiltrates after OLT for hepatitis C. Treatment with plasmapheresis and high-dose corticosteroids may be effective in patients with this disorder.

Adrenal Cortex Hormones↗
PubMed1998

Predictors of bile leaks after T-tube removal in orthotopic liver transplant recipients.

Bile leaks after T-tube removal are a frequent cause of morbidity in orthotopic liver transplant recipients. The aim of this study was to determine factors that predict the development of these leaks in liver transplant recipients. Records of all patients who had undergone liver transplantation at the University of Washington Medical Center between January 1990 and September 1993 were reviewed. The following were excluded: patients with a Roux-en-Y anastomosis or inadvertent early T-tube removal and patients who died or underwent retransplantation before T-tube removal. All T-tube cholangiograms were reviewed blindly by two authors. Using logistic regression, several variables were assessed for possible association with bile leaks after T-tube removal; these included patient demographics, intraoperative variables, and clinical and cholangiographic variables related to T-tube removal. Of the 166 liver transplants performed in 150 patients, 99 transplants in 97 patients were evaluable for bile leak after T-tube removal. Thirty-three patients developed symptomatic bile leaks, and 21 underwent endoscopic or operative intervention for persistent symptoms. Only duct mural irregularities on the final cholangiogram were strongly associated with the development of a bile leak after T-tube removal (P = 0.001). In conclusion, bile leaks after T-tube removal occurred in one-third of patients undergoing orthotopic liver transplantation; the majority of these patients required some intervention. Duct mural irregularities were associated with bile leaks.

Adolescent↗
PubMed1998

Biliary lipid composition after liver transplantation: effect of allograft function and cyclosporine.

Biliary lipid composition and bile flow are altered after orthotopic liver transplantation. Cyclosporine may have additional effects on biliary lipid composition and secretion. We studied the effects of liver transplantation, allograft function, and cyclosporine on biliary lipids in humans. Changes in lipid composition and secretion were correlated with serum cyclosporine levels, clinical events, and allograft function. Bile samples were withdrawn via a T-tube at interval time points in 17 patients during the first 3 months posttransplantation. Total and individual bile acid, cholesterol, and phospholipid were determined using high-performance liquid chromatography. Biliary lipid profiles were then correlated with clinical events, serum cyclosporine levels, and other clinical laboratory values. Biliary lipid concentrations decreased in 3 patients during periods of graft dysfunction (acute cellular rejection, drug-induced hepatitis, and inferior vena caval thrombosis) and increased with resolution of the graft injury. Serum cyclosporine levels were positively correlated with total bile acid, cholesterol, and phospholipid concentrations in bile. There was no relationship between the composition of secreted bile acids and serum cyclosporine levels. Bile acid, cholesterol, and phospholipid secretion were not uncoupled in the presence of cyclosporine. We concluded that (1) a decrease in biliary lipid concentrations may be an indicator of worsened graft function in some allografts; (2) biliary lipid concentrations are correlated with increasing cyclosporine levels; and (3) bile acid composition is unchanged, and uncoupling of secretion of other biliary lipids is not observed in the presence of cyclosporine.

Adolescent↗
PubMed1998

Endoscopic management of biliary strictures in liver transplant recipients: effect on patient and graft survival.

BACKGROUND: Biliary strictures in liver transplant recipients cause significant morbidity and can lead to reduced patient and graft survival. METHODS: Of 251 liver transplant recipients, 22 patients with biliary strictures were categorized into two groups: donor hepatic duct (n = 12) or anastomotic (n = 10). Strictures were dilated and stented. Endoscopic therapy was considered successful if a patient did not require repeat stenting or dilation for 1 year. RESULTS: Patient and graft survival did not differ significantly in the 22 patients compared with patients without strictures (relative risk of death and graft survival 1.8 and 1.3). Donor hepatic duct strictures required significantly longer therapy than anastomotic strictures (median days 185 versus 67, p = 0.02). Twenty-two months after the first endoscopic treatment, 73% of the donor hepatic duct stricture group were stent free compared with 90% of the anastomotic group (p = 0.02). The former group had significantly more (p < 0.05) hepatic artery thrombosis (58.3% versus 10%), cholangitis (58.3% versus 30%), choledocholithiasis (91% versus 10%), and endoscopic interventions. No patient undergoing endoscopic treatment required retransplantation or biliary reconstruction during a median follow-up of 35.7 months. CONCLUSION: Endoscopic therapy of biliary strictures after liver transplantation is effective and is not accompanied by reduced patient or graft survival.

Adult↗
PubMed1998

End-stage liver disease without hemochromatosis associated with elevated hepatic iron index.

BACKGROUND/AIMS: The utility of standard diagnostic tests for hereditary hemochromatosis in end-stage liver disease is unknown. A homozygous mutation (Cys 282 Tyr) has been identified in most patients with hereditary hemochromatosis. We examined whether serum iron studies and hepatic iron measurement distinguish end-stage liver disease patients with Cys 282 Tyr-associated hereditary hemochromatosis. METHODS: Serum iron, total iron binding capacity, and ferritin were measured in 106 cirrhotic patients prior to liver transplantation. Hepatic iron concentration and hepatic iron index were measured from explant liver tissue. Genotyping was performed on explant liver tissue in patients with an elevated hepatic iron index (>1.9). RESULTS: Thirty-three of 106 (31%) patients had elevated serum iron studies suggestive of hereditary hemochromatosis. Only four of 33 (12%) had a mean hepatic iron index >1.9, and none of the four patients was homozygous for Cys 282 Tyr. All four had liver disease due to hepatitis C and/or alcohol. CONCLUSIONS: (i) Serum transferrin saturation and hepatic iron index lack specificity for hereditary hemochromatosis in end-stage liver disease. (ii) Genotyping for Cys 282 Tyr may provide the best method to identify hereditary hemochromatosis in the setting of end-stage liver disease.

Female↗
PubMed1998

Estimation of the human liver volume and configuration using three-dimensional ultrasonography: effect of a high-caloric liquid meal.

The aim of this study was to investigate whether or not a magnetic position sensing system for free-hand acquisition of 3-D ultrasound images could be used to estimate liver volumes, and to study the effect of a high-caloric meal on these volumes in healthy subjects. In vitro accuracy was evaluated by scanning porcine and rabbit livers. Ten healthy subjects were examined fasting and 30 min after ingesting a high-caloric liquid meal. Portal and hepatic vein blood flow were measured by 2-D duplex sonography. The 3-D system yielded a strong correlation (r = 0.99) between true and estimated volumes in vitro. No significant increase in liver volume in response to the meal was seen. However, portal and hepatic vein flow volume increased significantly. Experience in human subjects suggests that a complete 3-D study of liver volumes can be obtained from multiple acoustic windows. In healthy subjects, no significant increase in liver volume was seen in response to ingestion of a high-caloric liquid meal.

Adult↗