Decision analysis in the clinical and imaging diagnosis of acute cholecystitis.

The importance of clinical, laboratory and imaging data in the diagnosis of acute cholecystitis (AC) was studied in 825 patients with right upper quadrant pain hospitalized in the Surgical Clinic of the Fundeni Hospital--Bucharest, between January 1, 1986 and June 30, 1988. A number of 21 parameters were analysed in each case. Of these 825 patients, 259 were considered after surgery as AC. These 259 cases were divided, after the microscopical examination of the surgically-obtained specimens, into two groups: 1) pathologically confirmed AC (137 cases) and 2) pathologically non-confirmed AC (122 cases). The importance of every parameter in establishing a histologically confirmed diagnosis of AC was determined by the diagnostic probability calculated according to Bayes'theorem. The hierarchy of the value of parameters in the diagnosis of AC was based on their capacity to distinguish between the cases histologically confirmed and those detected on surgery, but without microscopically demonstrated changes of AC. The same decision criterion was used in building the decision trees in the exploration of the cases of presumed AC. In the 825 cases with right upper quadrant pain, the main and most frequent cause was chronic calculous cholecystitis (31.8%), followed by AC pathologically confirmed (16.6%), AC non-confirmed (14.7%) and chronic acalculous cholecystitis (12.4%). The most useful parameters in distinguishing between pathologically confirmed AC and pathologically non-confirmed AC were: 1) sudden onset of pain; 2) mild resistance to abdominal palpation; 3) frank peritoneal irritation; 4) stone impacted in the gallbladder neck (ultrasonography); 5) fever; 6) palpable gallbladder; 7) lithiasis (ultrasonography); 8) gallbladder wall with double outline (ultrasonography). Ultrasonography supplied a diagnostic probability of 85% for the correct diagnosis of AC in cases without a clinical picture suggestive for AC. The decision tree analysis supported the same conclusion: only ultrasonography gives a good distinction between pathologically confirmed AC and pathologically non-confirmed AC.

The causal diagnosis of obstructive jaundice. A Bayesian approach.

To compare the contribution of clinical, laboratory and imaging data for the diagnostic accuracy in establishing the cause of obstructive jaundice, the records of 333 patients operated on for a presumed obstruction of the biliary ducts were analysed. The final diagnoses, after surgery, were divided into six groups: stones of the gallbladder and biliary tract, pancreatic cancer, biliary tract neoplasms, ampullary carcinoma, postoperative stenosis of the bile ducts, intrahepatic cholestasis (biliary cirrhosis, chronic cholangitis) and other causes of jaundice (liver tumours, cysts, extended cancer of the upper abdomen). Twenty-three parameters (9 clinical symptoms and signs, 10 biochemical alterations and 4 imaging methods) were examined. Not every case had all the investigations performed but the number of each group of data was large enough to allow a statistically significant conclusion. The contribution of each of the 23 parameters in increasing the probability of correct diagnosis was determined using a computer program based on Bayes' theorem. This analysis showed that for patients which presented suggestive clinical signs and symptoms for stones of the gallbladder and biliary tract and for pancreatic cancer, the diagnosis can be predicted with a probability of 90% only on the basis of clinical findings. The probability of a correct preoperative diagnosis was increased to 99% by imaging methods. On the contrary, for patients with a less clear diagnostic probability (with ampullary carcinoma, intrahepatic cholestasis and other causes) only ultrasonography and computed tomography could increase the probability of correct diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorption studies in patients with parasitic infestation of the small intestine, before and after treatment.

Forty adult patients having intestinal infestation with giardia or with parasitic associations, such as giardia-strongiloides, giardia-taenia solium, were subjected to morphological explorations, iron and vitamin B12 absorption tests, steatorrhea assay and serological tests, before treatment as well as six months and one year after eradication of the infection. On admittance, jejunal morphological lesions were noted only in 15 cases especially in associated infestation, iron depletion in six patients, vitamin B12 malabsorption in five patients and steatorrhea only in two cases. After the lapse of six months and one year, respectively, all the tests ranged within normal values, and the jejunal morphological aspect improved significantly indicating the pathogenetic role of intestinal parasites in the development of selective malabsorption.