The pancreas - Hindawi

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is possibly pancreatic stone protein. Secretin testing ~hows impaired bicarbonate secretion, and there is dim111ished out- put of trypsin in the Lundh test.
The pancreas

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lthough inrerventional endoscopy is well established in the management of bi lia ry discnse, its role in pancreatic Jbcase is just evnlving. Several studi es indicate rh,H in severe gallstone pancreatiti~. endoscopic sphinc te rotomy and gallstone extractinn exert a favorable effect on the outcome of the disease. Dr JGecnan described therapeutic approaches to this and other pancrc;:itic diseases. In traumatic post endoscopic retrograde cholangiopancrearography pancreatitis, nnsopancrentic drn111age appears LO be an effective approach to managemem. Acute recurrent pancrcatitis can result from a variety of pathologies, som e of which are amen ab le co enc.loscopic therapy. For exa mple , dysfunction of the ~phinccer of Oddi with delayed clearance of cnntrnsc and basal sphincreric pressures in excess of 40 mml-lg can he treated with endoscopic sph incterotomy; approximately 70% of such pat ients improve with this treatment. Pancreas di visum , occurring in about 7% of the population, is probably another cause of acute recurrent pancrcatitis. Endoscopic approaches to this problem include stcn ting of the minor papilla. In chron ic pa ncrcat itis the major aim is to relieve pain. The important questilm here i~ whether the rain is a function of obstruction . If sn, tech niques such as ba ll oon di lat io n of localized srricrurcs of the pancreatic duct may be helpful. Pancreatic duct stones may be removed or bypassed , though there is not yet enough follow- up to determine the va lue of these maneuvres. Other pa n creatic pathologies which may respond to e ndoscopic th erapies include pseudocysrs, which may occasionally be man.:iged with nasopancreatic catheter drainage. D r CS Pitchumoni gave an overview of tropical, nonalcoholic, calcifyi ng pancreatiris. This disease of obscu re et inlogy is fou nd in a band of±30° from the equator. The condition does not appear to be hereditary, a lthough about 8% of cases are famil ia l. It characteristically affects young adu lts, causing

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chron ic exocrine pancreatic insufficien cy and pain. A hrntlc type II diabetes mell1tus occu rs earl y (60% before the age of 30 years; 90% by 40). Associated cli nical feature~ incluJt emaciation, parotid swelli ng, cyanosis of the lirs and ,1~dominal distension. There is a strong association with malnutrition. A field study in Kernla, India recently 1denuf1cd approximately 28 cases in 28,000 individuals screened. Thert' is a suggestion that the incidence of the disease may he declining. The pathological hallmark of the condition 1s extensive pancreatic calcification with large duct stones (compared with those found in chronic alcohnl1c pa ncremitis). The stones h ave an amorphous centre rich 111 ch mmium, iron and nickel whi le rhe shell b predominant!\' composed of calcium. The nidus prote111 is immunolog ic.illy simi la r to that fou nd in stnnes in alcoholic pancreatitb, anJ is possibly pancreatic ston e protein. Secretin testing ~hows impaired bicarbonate sec retion, and there is dim111ished output of trypsin in the Lundh test. Pancreatic juice lactofernn levels are ra ised and scrum immunoreactive trypsinogen concen trations reduced. The pathogenesis, though elusive, 1s of great interest. A genetic factor may operate, hut clearly environmental causes must be sought. There has been interest in the possible role of cyanogenetic glyco$ide~ o f cassava, a nutri tional staple of the poorer people who re nd to ac4u1re this disease, hut the evidence for this is not con vincing. Other plant-deri ved compounds might be important. Oxygen free rad ical-media ted injury is a possib ili ty, hut t he in itiating factor is as yet unidentified. The cellu lar mechanisms involved early in the pathogenesis of acute pancrea titis were reviewed by Dr A SaluJa. Recent investigations suggest that intrace llula r activation of the protenlyte cascade of zymogens is initi ated through colocalization of acinar ce ll zymogen gran ules with lysosomes CAN

J GASTRt )ENTEROL VOL 4 No 8 N OVEMBER/DFCEMllFR 1990

World Congress reports

which contain nc id hydrolascs ~uch as cathcpsi n B, which is capable o f con vening trypsinogcn rn trypsin. In three models of acute pancremit 1s - the choli nc-Jeficient, ethinnine-supplementcd diet model in young female Swiss mi ce which produces a hemorrhagic panc rcati tis; the ecru kin hyperstimulation model, an ede matous pancreariris; and the Juct ohstrucrion mllJd in New Zealand rabbits - there is ev idence for the co- localization phenomenon. In each of these models amino acid uptake and export protein synthesis is normal, hue there is an apparent blockade of e nzyme secretion by the acinar cel l. There is 11tl good ev idence as yet that the colocalization phenomenon occurs in human dbcasc and, if 1t docs, how it is linked w the majm init i,ni ng factors, ie, passage of gallstones through the bi liary tract or ethanol abuse, is st ill unknown. Dr Klapdor addressed the issue of pancreatic carcinoma, noting that despite comiderablc advanLes in diagnll~llL power, the d isease was sull idemified at a rela ti vely la te a nd generall y incurable srnge. Appropriate rndiothernpy can achieve local control of the d1se,1se in a high proportion of cases. The techn iques of immunothernpy hold sllmc promise. Evidencc was presented that a combination of immunntherapy using appropriate monoclonal ant ibodies with cytotoxic drugs or cytok incs suc h as the interferons or tumour necros is factor, might provide somc control of the d1scasc, though it was emphasized that these tcchniqucs arc still m ,I very early phase of their development. Idemifirnt iun n( ,mt igcm pccu liar lll pancreatic cancer is essential to developing spec ific 1mmunutherapies. Dr Parri: Pour described studies of blood gmup antigens expressed un the plasmalcmma and intracellular organe lles o( normal and neoplastic human and h amster pancreatic cells. B anJ H arc norma l comtituents of pancreatic cclb, H ant igcn heing primarily assnciatcd with zymogcn granules. A amigen, on the other hand, appear~ to he a cancer-assuciated antigen when expressed in pancreat ic t issue. It is found by immunohistochemistry Ill he locali:cd to the micmvi llus membrane of tlw cancer cell , hut is also found tn associariun with nucleus and nucleolus. During neoplastic transform,ttinn, B ,md H a n11gens appear to red ist ribute in the cell, appcaring on the plasma lemma of ma lignanr cells. A pancreatitis worbhop addre.,sed v;ir ious aspects of acute and c hroni c pancrcatitis . D r Ham Beger reviewed the das~ificat ions of acu te pancreat itis - Marsei I!es 1963 and 1984. and Cambridge 1983 - and d tscus.~cd the h1boratory determinations which arc most usefu l in d1scriminat1ng hccwccn the relative ly benign acute interstit ial edematous pancrcatiti, and the seve re n ccmt izing p;incrcat it b . These Clltnprbe the serum levels of C-reaCLive protctn, l;ictatc dehydrogenasc and

the antiprotcases, together with cnmputed wmography scanning with enhancement. For dctermmmg the th crapcuuc strategy (or managing acutc pancreatitis, idenLificm itin of the followi ng clinical entit ic:. was particularly useful: intcrsut1al ede matous pancrea titis , sLcrilc and in fccte~I n l'crnt izing pancrcatitis, panc reatic abscess and pancreatic pscudocysr. Dr S Marb gave ,111 overv iL·w of chrun tc pancrcatit,s, drawing attcnLil>n to the heterogeneity of rhe condition frnm an et iologica l stand point a nd from considcrat ilm nf clinical features, while Or Bordalo em phasized histopathologica l heterogeneity with respect to patterns of fihrosi~. atrophy, ca lcificat ion and the prom ine nt lipid incl11s1nns nf chronic alL