Clinical evaluation of pancreatic excretion test with dimethadione and oral BT-PABA test in chronic pancreatitis

Management of Pancreatic Duct Stones: Extracorporeal Approach

Stone clearance with extracorporeal shock wave lithotripsy is a safe and effective procedure for large pancreatic calculi not extractable by the standard endoscopic retrograde cholangiopancreatography techniques. In properly selected patients, this minimally invasive approach should be offered as the first line of therapy instead of surgery. Complete stone clearance can be achieved in three-fourths with long-term pain relief in two-thirds of patients. Re-intervention is required in less than half of the patients. Future studies should compare the extracorporeal approach with intraductal lithotripsy using the pancreatoscope.

Diagnosis by Microbial Culture, Breath Tests and Urinary Excretion Tests, and Treatments of Small Intestinal Bacterial Overgrowth

Small intestinal bacterial overgrowth (SIBO) is characterized as the increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract and accompanies various bowel symptoms such as abdominal pain, bloating, gases, diarrhea, and so on. Clinically, SIBO is diagnosed by microbial culture in duodenum/jejunum fluid aspirates and/or the breath tests (BT) of hydrogen/methane gases after ingestion of carbohydrates such as glucose. The cultural analysis of aspirates is regarded as the golden standard for the diagnosis of SIBO; however, this is invasive and is not without risk to the patients. BT is an inexpensive and safe diagnostic test but lacks diagnostic sensitivity and specificity depending on the disease states of patients. Additionally, the urinary excretion tests are used for the SIBO diagnosis using chemically synthesized bile acid conjugates such as cholic acid (CA) conjugated with para-aminobenzoic acid (PABA-CA), ursodeoxycholic acid (UDCA) conjugated with PABA (PABA-UDCA) or conjugated with 5-aminosalicylic acid (5-ASA-UDCA). These conjugates are split by bacterial bile acid (cholylglycine) hydrolase. In the tests, the time courses of the urinary excretion rates of PABA or 5-ASA, including their metabolites, are determined as the measure of hydrolytic activity of intestinal bacteria. Although the number of clinical trials with this urinary excretion tests is small, results demonstrated the usefulness of bile acid conjugates as SIBO diagnostic substrates. PABA-UDCA disulfate, a single-pass type unabsorbable compound without the hydrolysis of conjugates, was likely to offer a simple and rapid method for the evaluation of SIBO without the use of radioisotopes or expensive special apparatus. Treatments of SIBO with antibiotics, probiotics, therapeutic diets, herbal medicines, and/or fecal microbiota transplantation are also reviewed.

Pancreatic calculi superimposed upon slow growing pancreatic cancer

We report on a 59 year old male patient with cancer of the head of the pancreas, upon which pancreatic calculi were superimposed during the 3 year clinical course. Pancreatic calculi were noted in the main pancreatic duct (MPD) on both computed tomographic scans and ultrasonographs of the abdomen approximately 10 months after the recognizable dilatation of the MPD. Existence of the calculi was confirmed by autopsy. Elemental analysis and infrared spectrophotometry of the calculi demonstrated that the main constituent of the calculi was calcium carbonate. Histopathological examination showed that the pancreatic cancer was moderately differentiated adenocarcinoma. Immunohistochemical studies revealed that pancreatic stone protein (lithostathine) was present in the cytoplasm of tumour cells. In this case, pancreatic cancer progressed to obstruct the MPD unusually slowly, resulting in stagnation of pancreatic secretion and subsequent formation of the calculi.

Dissolution of pancreatic stones by oral trimethadione in patients with chronic calcific pancreatitis

The effect of oral dissolution therapy for pancreatic stones was evaluated in patients with chronic calcific pancreatitis. The anti-epileptic agent trimethadione was given orally to 30 outpatients at a dose of 0.9-1.5 g daily. On plain X-ray films and CT scans of the abdomen, pancreatic stones began to be dissolved around 8 months of treatment, and diminished in size and number or disappeared in 21 patients (70%) during the mean follow-up period of 32 months. The effect of trimethadione treatment on dissolution of stones was not closely related to the aetiology of the disease, distribution and size of stones, previous history of surgical interventions, or the degree of pancreatic dysfunctions. In three patients who stopped this medication of their own accord, pancreatic stones re-increased or reappeared about 6 months later. During trimethadione treatment, impaired exocrine pancreatic function returned to normal in four of nine patients examined, and diabetes mellitus was well controlled by either diet therapy alone or oral hypoglycaemic agents in eight of 10 patients who did not need insulin before trimethadione treatment. Complete relief of pain was noted in 73% of patients during the treatment. Overall gains and no change in bodyweight were observed in 83% of patients. Mild photophobia was the most common side effect, but could be easily overcome by wearing sunglasses. No severe side effects were observed in the liver, kidney, blood or the eyeground. Pancreatic stones in 30 patients not treated with trimethadione neither disappeared nor diminished spontaneously. Trimethadione treatment may be a useful tool for chemical dissolution of pancreatic stones.

Biochemical tests in the diagnosis of chronic pancreatitis and in the evaluation of pancreatic insufficiency

Chronic pancreatitis (adults) and cystic fibrosis (children) are the most common diseases leading to exocrine pancreatic insufficiency that, when reduced to < 5% of normal function, is characterised by steatorrhoea. The pathogenesis of the former condition is outlined, and recent concepts are emphasized. Biochemical tests to detect pancreatic insufficiency and to identify pancreatic disease as the cause of steatorrhoea include: serum enzyme tests (lipase, amylase, trypsin); stool chymotrypsin; isotopic tests based upon the assimilation of [14C] lipids and starch or excretion of the isotope as breath CO2, as well as the dual-labelled Schilling test; oral function tests utilising substrates hydrolysed by pancreatic enzymes such as benzoyl tyrosyl-p-aminobenzoic acid and fluorescein dilaurate; and duodenal intubation studies following meal-induced or hormonal stimulation of the pancreas. The rationale for these tests and the cumulative clinical experience of their utility are reviewed. A recommended diagnostic strategy is briefly presented. The role of various biochemical procedures to evaluate the efficacy of pancreatic enzyme replacement therapy is also described.

Macroautoradiographic and densitometric studies of [14C]dimethadione in rats: accumulation of the compound in the pancreas

Whole-body autoradiographic and densitometric distribution studies were performed on rats to investigate the accumulation of [14C]dimethadione (DMO) in the pancreas. [14C]DMO was intravenously administered at a dose of 167 microCi/0.5 mg/kg. Animals were sacrificed 1, 15, 30, 60 and 180 min after administration of the radioactive compound. The compound was found to rapidly distribute in all body tissues. The distribution pattern of the compound in the pancreas was spotty or linear due to the presence of the radioactive compound in blood of intrapancreatic vessels and in pancreatic ducts at higher levels than parenchyma. The radioactivity of pancreatic ducts became more evident with time, indicating the gradual accumulation of the compound in the ducts. These findings provide morphological evidence that DMO is accumulated in the pancreas and possibly eliminated from pancreatic juice. Densitometry revealed that the levels of radioactive compound in the pancreas were virtually as high as those in the liver and kidney.

Dissolution of pancreatic stones by oral trimethadione in a dog experimental model

Experiments were conducted to develop a dissolution therapy for human pancreatic calculi in a dog experimental model of pancreatic calculi surgically prepared. On plain x-ray films of the abdomen, pancreatic calculi appeared in 19 of 39 dogs within 12 mo after operation. The antiepileptic agent trimethadione was given orally to 13 dogs at a dose of 1.0-1.5 g daily. Pancreatic calculi disappeared in 13 of 15 observations. The scanning electron microscopy, the elemental analysis, and the powder x-ray diffractometry of pancreatic calculi in this model revealed that the calculi closely resembled human pancreatic calculi, consisting mainly of a calcite of calcium carbonate. There was no histologic finding suggesting drug toxicity in the liver, the kidney, and the blood. Pancreatic calculi in 6 control dogs without the treatment neither disappeared nor diminished spontaneously. The oral treatment with trimethadione may have potential for dissolving human pancreatic calculi.

Chronic pancreatitis at early age of onset presenting interesting findings through endoscopic retrograde pancreatography and chemical analysis of nonopaque pancreatic concretion

This case concerns a 20-year-old male patient with an approximate 10-year history of recurrent and severe abdominal pain radiating to the back. Endoscopic retrograde cholangiopancreatography revealed a short obstructing stenosis of the main pancreatic duct in the head of the pancreas, marked and tortuous dilatation of the prestenotic portion of the main pancreatic duct and its side branches, and a filling defect in the side branch in the body of the gland. Pancreaticojejunostomy was performed to induce decompression of the pancreatic duct. Histology of the pancreas showed advanced chronic pancreatitis. Three nonopaque concretions were obtained at operation. The largest one, which was milky white in appearance and elastic and soft in consistency, proved to be made up of protein. The concretion was rich in acidic amino acids, but poor in basic or aromatic residues. The molar composition of amino acids in the concretion was, in decreasing order, aspartic acid, serine, valine, glycine, and glutamic acid. Powder x-ray diffractometry revealed no crystalline structures.

Comparative pharmacokinetic study of trimethadione and dimethadione for lysis of pancreatic stones

In order to investigate the biological equivalence of dimethadione (DMO) and its precursor trimethadione (TMO), comparative pharmacokinetic studies were performed in 6 beagle dogs. DMO and TMO power was given orally at the same molar dose of 1.0 g and 1.11 g (7.7 mM), respectively. Plasma concentration of DMO and TMO was determined at an appropriate interval. Four pharmacokinetic parameters were calculated from the plasma concentration-time curves of DMO and TMO; the peak plasma concentration (Cmax), the time to the peak concentration of Cmax (Tmax), the area under the plasma concentration-time curve (AUC), and the biological half-life (t 1/2). In the plasma concentration-time curve of DMO, Tmax after oral administration of TMO was longer than that after administration of DMO. This resulted from the presence of the conversion process of TMO to DMO in the body, because of the very short Tmax observed in the plasma concentration-time curve of TMO. Cmax, AUC and t 1/2 did not differ significantly between the drugs. The results obtained indicate that TMO is biologically equivalent to DMO in regard to plasma concentration of DMO.

Bentiromide test for assessing pancreatic dysfunction using analysis of para-aminobenzoic acid in plasma and urine. Studies in cystic fibrosis and Shwachman's syndrome

We evaluated the bentiromide test by analyzing para-aminobenzoic acid (PABA) in plasma and urine (a) for the identification of patients with complete pancreatic insufficiency and (b) as an alternative to the secretin-cholecystokinin test. Nine control subjects, 18 patients with cystic fibrosis, and 4 patients with Shwachman's syndrome were studied. Based upon the secretin-cholecystokinin test, pancreatic function was judged to be less than 0.1% of normal in 7 patients with cystic fibrosis and malabsorption and between 0.7% and 90% of control values in 11 patients with cystic fibrosis and 4 patients with Shwachman's syndrome without malabsorption. The bentiromide test was performed in two stages: first with bentiromide alone, then with equimolar free PABA. After ingestion of free PABA, the plasma profile and urinary excretion of PABA were comparable in controls, patients with cystic fibrosis, and patients with Shwachman's syndrome. Thirty minutes after oral bentiromide, plasma PABA values in patients with and without malabsorption were significantly lower than in the control group. From 60 to 180 min after ingestion, plasma PABA levels in patients without malabsorption were no different from controls; whereas levels in patients with malabsorption were significantly lower than in controls and in those without malabsorption, reaching the highest significance at 90 min. Similar results were obtained when the urinary excretion of PABA was considered. Only the 90-min plasma test reliably detected cystic fibrosis patients with steatorrhea, however. Duodenal colipase output was highly correlated with both the 90-min plasma test and the urinary excretion of PABA, with similar results for lipase and trypsin output. Reliable detection of pancreatic dysfunction, nevertheless, was not obtained even with the plasma test, in cystic fibrosis patients with greater than 5%-10% of the mean normal enzyme output. In patients with Shwachman's syndrome, none of whom had malabsorption, the plasma and urinary test failed to detect pancreatic dysfunction even with enzyme output as low as 1% of normal.

The excretion of dimethadione in pure pancreatic juice and bile in postoperative patients

The excretion of dimethadione (DMO) in pure pancreatic juice and bile was studied in postoperative patients undergoing external drainage of pancreatic juice and in those who had undergone percutaneous transhepatic cholangiodrainage. During and after oral administration of trimethadione, which is the precursor of DMO, pancreatic DMO concentration closely paralleled plasma DMO concentration. Pancreatic juice/plasma concentration ratio for DMO exceeded 1.0. In a patient with a large pancreatic cyst communicating with the main pancreatic duct, pancreatic DMO concentration after single rapid injection of secretin inversely correlated with the flow rate, while its output depended directly on the rate. Biliary DMO output after secretin injection was closely dependent on the flow rate, but was extremely low. The present results are essentially compatible with the findings previously observed in dogs.