Pancreatic phlegmon. Clinical features and course

Early ductal decompression versus conservative management for gallstone pancreatitis with ampullary obstruction: a prospective randomized clinical trial

OBJECTIVE

To compare the efficacy of endoscopic retrograde cholangiopancreatography +/- endoscopic sphincterotomy (ERCP +/- ES) versus traditional conservative management in early gallstone pancreatitis with persistent ampullary obstruction (GSP + AO).

SUMMARY BACKGROUND DATA

The effectiveness of early ERCP +/- ES in this setting is controversial.

METHODS

Sixty-one consecutive patients with GSP + AO within 48 hours from the onset of symptoms were randomized to receive either conservative treatment and selective ERCP +/- ES after 48 hours (control group, 31 patients) or initial conservative treatment and systematic ERCP +/- ES within 48 hours if obstruction persisted 24 hours or longer (study group, 30 patients). Patient outcome was compared in relation to treatment groups and to duration of obstruction.

RESULTS

In the control group, 22 patients disobstructed spontaneously within 48 hours; 3 of the remaining 9 patients underwent ERCP +/- ES and none had impacted stones. In the study group, 16 patients disobstructed spontaneously and 14 underwent ERCP within 48 hours from the onset of symptoms; impacted stones were found and extracted by ES in 79% (11 of 14) of these.

PATIENTS

There were no deaths in either group. Patients in the study group showed a shorter period of obstruction (P = 0.016) and a lower rate of immediate complications (P = 0.026) than controls. Patients with obstruction lasting < or =48 hours regardless of the treatment group had fewer immediate complications than those whose obstruction persisted longer (P < 0.001).

CONCLUSIONS

This study shows that in patients with GSP + AO limiting the duration of obstruction to not longer than 48 hours by ERCP + ES decreased morbidity.

CT-guided aspiration of suspected pancreatic infection: bacteriology and clinical outcome

We have performed CT-guided percutaneous needle aspiration in 104 patients with severe pancreatitis strongly suspected of harboring pancreatic infection on the basis of systemic toxicity and CT findings (Balthazar CT grade D or E). Of these 104 patients, 51 (49%) were documented with pancreatic infection. Gram stain was positive in 54 of 58 infected aspirates, and culture was positive in all 58. Klebsiella, Escherichia coli, and Staphylococcus aureus were the most frequent organisms. Eighty-six percent of infected processes contained only one organism. Overall, pancreatic infection was documented by GPA within the first 2 wk in approx one-half of patients. There were no complications. The overall rate of infection decreased from 60 (1980-1987) to 34% (1988-1995) (p = 0.011). This change was caused by a reduction in the rate of infected necrosis from 67 to 32% (p = 0.015). The overall mortality rate remained at 20%. The mortality of sterile pancreatitis was not different from infected pancreatitis (p = 0.14). We conclude that GPA is a safe, accurate method of diagnosis of pancreatic infection. The rate of pancreatic infection appears to be decreasing. The overall mortality of severe pancreatitis among patients suspected of harboring pancreatic infection has remained unchanged because of the high mortality associated with both infected necrosis and severe sterile necrosis.

Classification and treatment of local septic complications in acute pancreatitis

BACKGROUND

An international symposium on acute pancreatitis recently developed a clinical classification system for severe acute pancreatitis that classifies all local septic complications into three groups: infected necrosis (IN), sterile necrosis (SN), and pancreatic abscess (PA). Despite the appeal of having three distinct, well-defined labels for this complex process, the clinical utility of this schema has yet to be determined. The purpose of this study was to investigate the prognostic and therapeutic utility of applying this clinical classification system to a large group of surgical patients with local septic complication from acute pancreatitis.

PATIENTS AND METHODS

We reviewed the cases of 62 patients with complicated pancreatitis, classifying them into IN (n = 20), SN (n = 14), or PA (n = 28) groups. Ranson's score, APACHE II score, and computed tomography grading were calculated within the first 48 hours of admission. Information on patient demographics, etiology of pancreatitis, operative procedures, timing of intervention, bacteriology, blood loss, intensive care unit days, ventilator days, and morbidity and mortality were also accrued and analyzed.

RESULTS

Despite similar demographics and etiology of pancreatitis, patients with necrosis, both IN and SN, were more critically ill than were patients with PA (APACHE II score > 15, 21% versus 0%, respectively), required earlier operative intervention (mean 14 days versus 29 days, P = 0.02), required necrosectomy with drainage (65% versus 4%, P < 0.001) rather than simple drainage (3% versus 86%, P < 0.001), more reoperations (2.3 versus 1.1, P < 0.05), and had a significantly higher mortality rate (35% versus 4%, P < 0.05). In addition, patients with IN required significantly more hospital days, ventilator days, and blood transfusions than either patients with SN or PA (P < 0.05).

CONCLUSIONS

We conclude that this classification system allows for the stratification of patients into three distinct groups--infected necrosis, sterile necrosis, and pancreatic abscess--and has both therapeutic and prognostic usefulness.

The resource implications of severe necrotizing pancreatitis treated by necrosectomy

This study reviews the resource utilization of patients admitted to the Intensive Care Unit (ICU) with severe necrotizing pancreatitis treated by early necrosectomy. For 21 patients there was a total of 221 abdominal operations, 2365 hospital days, 565 ICU days and 1185 days of parenteral nutrition. The mortality rate was 43%. The treatment for patients with necrotizing pancreatitis is 10 times more resource intense than other admissions to the ICU. The implications of necrotizing pancreatitis treated by necosectomy in the context of a Diagnosis-Related Groups Prospective Payment model of hospital funding are discussed.

Pancreatic infection complicating acute pancreatitis

Pancreatic infection is the leading cause of death from acute pancreatitis. Patients with severe necrotizing pancreatitis are most at risk. Early computed tomography and percutaneous fine-needle aspiration microbiology of areas of pancreatic necrosis enable early diagnosis. Pancreatic infection should be treated surgically, although sterile necrosis may be managed conservatively. The role of antimicrobial drugs is uncertain.

Pancreatic abscess and other pus-harboring collections related to pancreatitis: a review of 108 cases

This is a report on 108 cases collected from 1970 to 1987, in the same department, of surgically-detected pancreatic abscesses or pus-harboring collections. The purulent areas were either of a spreading pattern or represented a clearly localized mass. To the spreading pattern belong 47 cases of necrotizing pancreatitis, without discontinuity in the clinical course from the early toxic to the late septic phase, 4 cases of acute pancreatitis, initially in remission and later complicated by septic collections, and 4 cases which developed after an acute attack of chronic pancreatitis. The abscess pattern was made up of 19 each of pseudocysts and predisposing pancreatitis, 10 cases of chronic pancreatitis, and only 5 necrotizing "nonstop" pancreatitis. The surgical treatment in all cases consisted of multiple drainages and postoperative irrigation. We exclude 3 cases of associated open packing. The etiological, clinical, and biochemical features of each group of patients are reported and discussed. Computed tomography availability seems to be the most important improvement reported as regards diagnosis and surgical tactics. The overall mortality rate was 15.7% with a significant difference between the 2 patterns (23.6% for the spreading pattern versus 7.5% for the abscess pattern). On the basis of this experience, it is possible to establish a relationship between the gross appearance of the collection and the underlying pancreatic disease with differences in terms of prognosis, morbidity, and mortality. Finally, a simple nomenclature can be chosen which is capable of distinguishing between the diverse pancreatic purulent collections. While the presence of pus may characterize the course of severe acute pancreatitis in many cases, the low incidence of "true" pancreatic abscess is emphasized.

Management of complicated acute pancreatitis: impact of computed tomography

The usefulness of computed tomography (CT) in guiding the management of 43 patients who had a complicated clinical course of acute pancreatitis was retrospectively studied. The CT scans were performed when patients had persistent fever, leucocytosis, hyperamylasaemia, palpable abdominal masses or when there was organ failure. The CT scans showed normal findings in six patients, features of pancreatic abscess in three patients, pseudocysts in three patients and inflammatory masses (a mixture of sterile inflammation and necrosis) in 31 patients. Patients with pancreatic abscesses underwent emergency laparotomy, drainage and debridement; patients with pseudocysts had delayed drainage unless complication occurred; patients with normal CT scan or findings of inflammatory masses were managed conservatively. For patients undergoing conservative management, repeated CT scanning and percutaneous aspiration of the inflammatory mass was performed when pancreatic sepsis was strongly suspected. By this approach, basing on careful clinical and CT scan surveillance, five patients with pancreatic sepsis (pancreatic abscess and localized abscess collection in pseudocyst) underwent emergency surgery and four survived, while 25 patients with inflammatory masses were successfully managed conservatively and some who may have been operated on clinical grounds were spared unnecessary early debridement surgery.

Pancreatic phlegmon: what is it?

In a retrospective study of 264 patients with acute pancreatitis, 22 were identified as having phlegmon by combined radiologic and clinical criteria. The radiologic criteria consisted of demonstration of abnormal lesion on computed tomography scan which was composed of masses of mixed density, free of extraluminal gas and lacking a well-defined wall. The clinical criteria was that the clinical course was free of sepsis. Half of the group thus identified had severe pancreatitis as defined as having three or more poor prognostic signs. Fever, leukocytosis, and serum amylase elevation persisted for a longer period than usual. Complication was infrequent but the lesion could persist for 3 to 4 months without producing symptoms. This is a relatively benign condition and surgery should be avoided.

Differentiating pancreatic pseudocyst and pancreatic necrosis using computerized tomography

Ten per cent of patients with acute pancreatitis will develop pancreatic complications. Differentiating pancreatic pseudocyst formation from pancreatic necrosis may be difficult based on clinical grounds. The purpose of this study was to evaluate the role of computerized tomography in differentiating these processes. A retrospective analysis was performed of 40 patients who developed pancreatic complications following an episode of acute pancreatitis and who subsequently underwent operation for drainage of their pancreatic fluid collections. All 40 patients had abdominal CT scans performed before surgery and the patients were then categorized on the basis of CT findings as having (1) a pseudocyst with a well-defined cyst wall, (2) peripancreatic fluid marked by the absence of a cyst wall, and (3) a combination of a pseudocyst as well as free peripancreatic fluid. Patients with pseudocysts had an average hospital stay of 14 +/- 2 days, a hospital morbidity rate of 16%, and a hospital mortality rate of 0%. In contrast, patients with peripancreatic fluid collections had an average hospital stay of 43 +/- 4 days (p less than 0.01) and hospital morbidity and mortality rates of 74% (p less than 0.01) and 22% (p less than 0.05), respectively. Patients with both pseudocysts and peripancreatic fluid collections behaved in a similar fashion to patients with peripancreatic fluid alone as characterized by a prolonged hospital stay and a high incidence (80%) of postoperative complications. At one year follow-up, 89% of the patients with pseudocysts were asymptomatic, whereas only 13% (p less than 0.01) of patients with peripancreatic fluid were symptom free. These data demonstrate that pseudocyst and peripancreatic fluid collections have markedly different biologic characteristics both in their short-term and long-term behavior. The results suggest that CT scanning can differentiate these processes and may help in directing the appropriate surgical therapy.

Contrast-enhanced abdominal computed tomography scanning and prediction of severity of acute pancreatitis: a prospective study

One hundred and fifty-two patients were admitted to a single hospital with a diagnosis of acute pancreatitis during a 31-month period. Of these, 126 patients had contrast-enhanced abdominal computed tomography (CT) scans within 72 h of admission; 92 of these attacks were clinically mild, 34 were clinically severe. A single consultant radiologist reported the scans 'blind' and noted whether pancreatic enhancement was normal, increased or decreased, and whether there was loss of peripancreatic tissue planes. The maximum anteroposterior measurement of the pancreatic head and body were multiplied together to produce a 'pancreatic size index' (cm2). Significantly more patients with severe attacks had decreased pancreatic enhancement (79 versus 58 per cent, P = 0.01) and loss of peripancreatic tissue planes (82 versus 54 per cent, P = 0.006). The median (range) pancreatic size index for clinically severe attacks was 12.8 cm2 (3.0-52.5), and for mild attacks was 6.0 cm2 (1.1-23.4), P less than 0.0001. Modified Glasgow criteria had a sensitivity of 85 per cent and specificity of 79 per cent for clinically severe attacks. A pancreatic size index of greater than or equal to 10 cm2 had a sensitivity of 71 per cent and specificity of 77 per cent for clinically severe attacks. In conclusion, although there were highly significant differences between the clinically severe and mild groups with respect to pancreatic enhancement, peripancreatic tissue planes and pancreatic size indices, these CT criteria did not improve on modified Glasgow criteria for prediction of disease severity.

Value of contrast-enhanced computerized tomography in the early diagnosis and prognosis of acute pancreatitis. A prospective study of 202 patients

Two hundred two patients admitted with the clinical suspicion of acute pancreatitis underwent computerized tomography scanning within 36 hours of admission. The diagnostic value of the computerized tomography findings was excellent, with a sensitivity of 92 percent and a specificity of 100 percent. One hundred seventy-six patients with acute pancreatitis defined according to the overall clinical course were included in the prognostic study. The pancreatitis was fatal in 21 patients, severe in 47 patients, and mild in 108 patients. The computerized tomography findings were classified into the following three groups on the basis of the extent of phlegmonous extrapancreatic spread: Group I, no phlegmonous extrapancreatic spread (100 patients, none died); Group II, phlegmonous extrapancreatic spread in one or two areas (28 patients, mortality rate 4 percent); and Group III, phlegmonous extrapancreatic spread in three or more areas (48 patients, mortality rate 42 percent) (p less than 0.0001). The following three scores from prognostic clinical and laboratory data were also obtained: Score 1, zero or one positive sign (82 patients, none died); Score 2, two to four positive signs (54 patients, mortality rate 13 percent); Score 3, five or more positive signs (40 patients, mortality rate 35 percent) (p less than 0.001). The combination of computerized tomography findings and prognostic signs had the best predictive value. Patients in Group III, Score 3 (24 patients) or Group III, Score 2 (19 patients) had mortality rates of 58 percent and 32 percent, respectively, and complications developed in all of the survivors. In addition, all except two acute pancreatitis patients in whom pancreatic abscess developed were found in Group III (p less than 0.0001). Furthermore, for Group III patients, the prediction of death associated with abscesses was enhanced by the number of prognostic signs. The mortality rate increased from 17 percent for Score 2 patients to 81 percent for Score 3 patients (p = 0.0078). As a result of this study, we recommend early computerized tomography for all Score 2 and Score 3 patients, since it allows prompt recognition of patients at high risk for systemic and local complications. Adequate therapy can then be directed to the group of patients to whom it is best suited. Serial computerized tomographies should be reserved for those patients presenting with phlegmonous extrapancreatic spread.

Early diagnosis of pancreatic infection by computed tomography-guided aspiration

We performed 92 computed tomography-guided percutaneous needle aspirations of pancreatic inflammatory masses in 60 patients suspected of harboring pancreatic infection. Thirty-six patients (60%) were found by Gram stain and culture to have a total of 41 separate episodes of pancreatic infection. Among 42 aspirates judged to be infected by computed tomography-guided aspiration, all but one were confirmed by surgery or indwelling catheter drainage. Among 50 aspirates judged to be sterile, no subsequent evidence of infection was found. All patients tolerated the procedure well and no complications were noted. As a result of this technique, we observed that pancreatic infection occurs earlier than has been previously appreciated (within 14 days of the onset of pancreatitis in 20 of the 36 patients) and that infection may recur during prolonged bouts of pancreatitis. We conclude that guided aspiration is a safe, accurate method for identifying infection of the pancreas at an early stage.

Pancreatic abscess and infected pancreatic necrosis. Different local septic complications in acute pancreatitis

Local septic complications in acute pancreatitis need to be exactly characterized and defined in order to develop improved concepts for their prevention, early diagnosis, and therapy. While up to now all local septic complications have been termed abscesses, the present study for the first time delineates the morphologic, clinical, and laboratory criteria needed to distinguish between two separate clinical entities: the infected necrosis (IN) and the pancreatic abscess (PA). IN is defined as a diffuse bacterial inflammation of necrotic pancreatic and peripancreatic tissue, but without any significant pus collections. On the other hand, the morphologic substrate of PA is a localized collection of pus surrounded by a more or less distinct capsula. IN becomes clinically evident during the early phase of acute pancreatitis (AP). The patients with IN present both the signs of sepsis and the laboratory findings of AP. Thus in these patients the most fulminant course of AP is observed; 51.8% and 35.7% of them have pulmonary or renal insufficiency, respectively. The mortality of the patients with IN is high and amounts to 32.1%. Pancreatic abscess, on the other hand, does not develop before the fifth week after onset of symptoms and after subsidence of the acute phase of pancreatitis. In these patients laboratory signs of AP-like amylasemia, hypocalcemia, hyperglycemia, and rise of LDH are rarely observed. Corresponding to the lack of pathophysiologic effects of AP per se, pulmonary and renal insufficiencies occur in only 33.3% and 16.7%, respectively, and mortality in these patients is 22.2%. While an abscess may readily be identified by computed tomography, the differentiation between IN and non-IN can be very difficult.(ABSTRACT TRUNCATED AT 250 WORDS)