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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical consequences of intestinal malabsorption are extremely variable and a dissociation between malabsorption, malabsorption syndrome and enteropathy is often noted. Enteropathy does not always results in malabsorption and in an alteration of the tests exploring the absorptive function. The following have particular relevance in clinical practice: coeliac disease, malabsorption induced by microbiologic agent (including Whipple's disease), post-surgical malabsorption and selective carbohydrate malabsorption. In particular, coeliac disease has been analyzed in its various aspects, from studies with organ cultures to immunological hypotheses, from the classical variety to subclinical forms and to serious complications, such as enteropathy-associated T cell lymphoma. Malabsorption syndromes are dramatically underdiagnosed: in the typical case of coeliac disease, enteropathy represents a clinical iceberg, and the discovery of the submerged portion, represented by the polymorphous subclinical varieties, has just started. As far as intestinal malabsorption is concerned, the main clinical problem regards diagnosis.
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PMID:[Intestinal malabsorption, celiac disease and associated lymphoma: from symptoms to diagnosis]. 853 67

Two adult cases of extranodal malignant lymphoma diffusely involving the intestinal wall are reported. Lymphoblastic lymphoma in case 1 (68-year-old male) and small lymphocytic lymphoma in case 2 (48-year-old male) were initially manifested as protein-losing enteropathy or malabsorption syndrome. In case 1, the patient died of massive ascites and intestinal bleeding 10 months after presentation. Autopsy revealed diffuse and extensive lymphomatous involvement of the small and large intestine, peritoneum and liver. The patient in case 2, showing low-grade diffuse lymphomatous invasion throughout the small bowel mucosa without involving other organs, is currently being followed up. Surface marker studies revealed previously undescribed phenotypes, such as CD4/CD8 double-positive blastoid T cells in case 1, and CD8-positive suppressor/killer T cells in case 2. T-cell receptor alpha/beta was expressed on the lymphoma cells in both cases. Epstein-Barr virus infection was not evident. The gut-associated nature of the T-lymphoma cells, possibly of extrathymic origin, is discussed.
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PMID:T-cell lymphomas diffusely involving the intestine: report of two rare cases. 876 87

Long standing coeliac disease is associated with an increased risk of malignancy, not only of intestinal lymphoma but also small intestinal adenocarcinoma. Two patients whose initial presentation was adenocarcinoma of the small bowel, but who were subsequently found to have coeliac disease after Whipple's resection, are described. The diagnosis was made early in the postoperative period in the first patient after close histological examination of the tumour-free mucosal margins. This patient was placed on a gluten-free diet and had an uncomplicated postoperative recovery with rapid weight gain. Diagnosis and dietary intervention in the second patient was very delayed and resulted in the development of severe malabsorption and weight loss. This illustrates the importance of ruling out coeliac disease prior to surgery in patients with small intestinal malignancies.
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PMID:Duodeno-jejunal adenocarcinoma as a first presentation of coeliac disease. 930 51

A 22-year-old Libyan patient suffering from chronic diarrhea presented with an alpha-heavy chain paraprotein and a lympho-plasmacellular lymphoma infiltration of the duodenal mucosa. These findings supported the diagnosis of "immunoproliferative small intestinal disease" (IPSID). In this disease, that occurs almost solely in countries with low socioeconomic status, a diffuse infiltration of small intestinal mucosa by neoplastic lymphoid cells causes chronic malabsorption. About 65% of patients exhibit a paraprotein in serum, urine or jejunal juice that consists of the heavy chain of immunoglobulin A (alpha-heavy chain). In advanced stages, IPSID resembles histologically and clinically high grade lymphoma: some patients develop masses in the gut wall, an abdominal lymphadenopathy and involvement of other organs including bone marrow. The disease is believed to be triggered by a chronic infectious antigenic stimulus. Thus, in early stages in some patients cure may be achieved by antibiotic therapy alone. In advanced disease, chemotherapy including anthracyclins is necessary.
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PMID:[Libyan patient with chronic diarrhea]. 901 23

Since its introduction in 1987, zidovudine monotherapy has been the treatment of choice for patients with HIV infection. Unfortunately it has been established that the beneficial effects of zidovudine are not sustained due to the development of resistant viral strains. This has led to the strategy of combination therapy, and in 1995 treatment with zidovudine plus didanosine, or zidovudine plus zalcitabine, was demonstrated to be more effective than zidovudine monotherapy in preventing disease progression and reducing mortality in patients with HIV disease. Recent work demonstrates an even greater antiviral effect from triple therapy with 2 nucleosides, zidovudine plus zalcitabine with the addition of saquinavir, a new protease inhibitor drug. The HIV protease enzyme is responsible for the post-translational processing of gag and gag-pol polyprotein precursors, and its inhibition by drugs such as saquinavir, ritonavir, indinavir and VX-478 results in the production of non-infectious virions. As resistance may also develop to the protease inhibitors they may be used in combination, and future strategies may well include quadruple therapy with 2 nucleoside analogues plus 2 protease inhibitors. Administration of protease inhibitors alone or in combination with other drugs does raise a number of important pharmacokinetic issues for patients with HIV disease. Some protease inhibitors (e.g. saquinavir) have kinetic profiles characterised by reduced absorption and a high first pass effect, resulting in poor bioavailability which may be improved by administrating with food. Physiological factors including achlorhydria, malabsorption and hepatic dysfunction may influence the bioavailability of protease inhibitors in HIV disease. Protease inhibitors are very highly bound to plasma proteins (> 98%), predominantly to alpha 1-acid glycoprotein. This may influence their antiviral activity in vitro and may also predispose to plasma protein displacement interactions. Such interactions are usually only of clinical relevance if the metabolism of the displaced drug is also inhibited. This is precisely the situation likely to pertain to the protease inhibitors, as ritonavir may displace other protease inhibitor drugs, such as saquinavir, from plasma proteins and inhibit their metabolism. Protease inhibitors are extensively metabolised by the cytochrome P450 (CYP) enzymes present in the liver and small intestine. In vitro studies suggest that the most influential CYP isoenzyme involved in the metabolism of the protease inhibitors is CYP3A, with the isoforms CYP2C9 and CYP2D6 also contributing. Ritonavir has an elimination half-life (t1/2 beta) of 3 hours, indinavir 2 hours and saquinavir between 7 and 12 hours. Renal elimination is not significant, with less than 5% of ritonavir and saquinavir excreted in the unchanged form. As patients with HIV disease are likely to be taking multiple prolonged drug regimens this may lead to drug interactions as a result of enzyme induction or inhibition. Recognised enzyme inducers of CYP3A, which are likely to be prescribed for patients with HIV disease, include rifampicin (rifampin) [treatment of pulmonary tuberculosis], rifabutin (treatment and prophylaxis of Mycobacterium avium complex), phenobarbital (phenobarbitone), phenytoin and carbamazepine (treatment of seizures secondary to cerebral toxoplasmosis or cerebral lymphoma). These drugs may reduce the plasma concentrations of the protease inhibitors and reduce their antiviral efficacy. If coadministered drugs are substrates for a common CYP enzyme, the elimination of one or both drugs may be impaired. Drugs which are metabolised by CYP3A and are likely to be used in the treatment of patients with HIV disease include the azole antifungals, macrolide antibiotics and dapsone; therefore, protease inhibitors may interact with these drugs. (ABSTRACT TRUNCATED)
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PMID:Protease inhibitors in patients with HIV disease. Clinically important pharmacokinetic considerations. 908 59

A number of hepatobiliary tract and pancreatic disorders have been documented in patients with celiac disease. Some disorders have shared immunological or genetic factors, including chronic hepatitis, primary biliary cirrhosis and sclerosing cholangitis. Other hepatic or pancreatic pathological changes in celiac disease have been documented with severe malnutrition and malabsorption, including hepatic steatosis and pancreatic insufficiency, sometimes with pancreatic calcification. Finally, celiac disease may be associated with other very rare hepatic complications, such as hepatic T cell lymphoma.
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PMID:Hepatobiliary tract and pancreatic disorders in celiac disease. 911 4

We report a case of enteropathy-associated T-cell lymphoma (EATL) of the jejunum in a 56-year-old man. The patient suffered for several years from nonspecific abdominal complaints, with no clinical evidence of malabsorption. The patient underwent extensive imaging procedures including barium meal and computed tomography. Computed tomography of the abdomen showed small mesenteric lymph nodes and an area of intestinal wall thickening. Barium meal demonstrated a short jejunal stricture. Histology revealed lymphoma of the jejunum, with microscopic changes distant from the lesion consistent with celiac disease. The spectrum of EATL ranges from patients with frank celiac disease, to patients with only immunohistochemical evidence of celiac disease, who develop small bowel lymphoma.
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PMID:Enteropathy-associated T-cell lymphoma: a case report with radiographic and computed tomography appearance. 917 68

We describe a case of stage IE diffuse small cleaved B-cell lymphoma involving primarily the head of pancreas in a patient with chronic malabsorption as a result of short bowel syndrome. The association of chronic malabsorption with lymphoma and other cancer is reviewed. The possible role of dietary fat as an etiologic link to this association is speculated.
Leuk Lymphoma 1997 Jul
PMID:Primary pancreatic lymphoma associated with short bowel syndrome: review of carcinogenesis of gastrointestinal malignancies. 932 5

An association between celiac disease and non-Hodgkin's lymphoma of the small intestine has been recognized for many years. Coeliac disease is characterized by an enteropathy sensitive to gluten, malabsorption of food and partial or total villous atrophy. Also malignant lymphoma may present with malabsorption and mucosal lesion similar to that found in coeliac patients. The diagnosis of lymphoma in coeliac patients can be extremely difficult because the presenting symptoms and histological lesion are similar, but the presence of a cluster of symptoms such as abdominal pain malabsorption, weight loss in patients older than 40 years with a history of poorly responsive coeliac disease should raise a suspicion of malignancy. We present a case of 55 year-old man with malignant lymphoma and coeliac disease surgically treated in our Institute for intestinal obstruction.
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PMID:[Problems of differential diagnosis of lymphoma and celiac disease. A case report]. 941 4

Celiac disease is a genetic, immunologically mediated small bowel enteropathy that causes malabsorption. The immune inflammatory response to gluten frequently causes damage to many other tissues of the body. The condition is frequently underdiagnosed because of its protean presentations. New prevalence data indicate that symptomatic and latent celiac disease is present in one of 300 people of European descent. Age of onset ranges from infancy to old age. Symptomatic presentations include general ill-health, as well as dermatologic, hematologic, musculoskeletal, mucosal, dental, psychologic and neurologic diseases. Celiac disease has a 95 percent genetic predisposition and, thus, it is frequently associated with autoimmune conditions such as diabetes mellitus type 1 and thyroid disease. Untreated patients have an increased incidence of osteoporosis and intestinal lymphoma. Excellent diagnostic screening tests are now available, including those that detect antigliadin and antiendomysial antibodies. Therapy with a gluten-free diet is effective, resulting in complete resolution of symptoms and secondary complications in almost all patients. Local and national celiac-sprue associations facilitate care of patients with celiac disease and support dietary compliance.
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PMID:Detecting celiac disease in your patients. 951 50


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