Tc-99 hexamethylpropyleneamineoxide scanning for the detection of acute appendicitis.

BACKGROUND: Patients with acute lower abdominal pain remain a diagnostic challenge. Although acute appendicitis is the most common surgical disorder, its accurate and timely diagnosis can be difficult. Historically, females of childbearing age are the most difficult patient group in whom to make the diagnosis of acute appendicitis; they have reported negative laparotomy rates ranging from 30 to 50 percent. Tc-99 hexamethylpropyleneamineoxide (HMPAO) labeled leukocyte scan has previously been shown to be very accurate in the detection of acute appendicitis. STUDY DESIGN: One year ago, a blinded study using Tc-99 HMPAO labeled leukocyte scan was reported for the detection of acute appendicitis. That study consisted of 27 patients who presented with abdominal pain. The present report is a follow-up study of 37 additional patients in whom the Tc-99 HMPAO leukocyte scan was used to diagnose or discount acute appendicitis. RESULTS: Twenty-seven patients had histologically proved acute appendicitis. Twenty-three of these were correctly diagnosed using the leukocyte scan, for a sensitivity rate of 85 percent. The overall specificity rate was 93 percent, with an overall accuracy rate of 89 percent. Thirty-one of 64 patients were females of reproductive age and represented 56 percent of all patients in the study with appendicitis. In this group, the Tc-99 HMPAO leukocyte scan had a sensitivity rate of 87 percent, specificity rate of 92 percent, and an overall accuracy rate of 89 percent. The Tc-99 HMPAO leukocyte scan also proved to be valuable in the diagnosis of other intra-abdominal inflammatory conditions. Eight scans interpreted as negative for acute appendicitis were positive for other conditions, including five that were positive for diverticulitis, one for a tumor, one for a tubo-ovarian abscess, and one for a small intestinal infarction. CONCLUSIONS: The Tc-99 HMPAO leukocyte scan is a highly accurate, diagnostic, and minimally invasive test of use in patients with abdominal pain of unclear cause, in which the differential diagnosis includes acute appendicitis. It is of particular value in females of childbearing age, in whom the cause of lower abdominal pain is unclear.

Detection of acute appendicitis by technetium 99 HMPAO scanning.

The diagnosis of acute appendicitis can be difficult. Barium enemas, computed tomography (CT) scans, ultrasound examinations and Indium scans are used to aid in making the diagnosis with varying degrees of success. This blinded, prospective study reports the use of a Technetium 99-m Hexamethylpropyleneamineoxide (HMPAO) labelled white blood cell scan in 30 patients with suspected appendicitis. Autologous white blood counts from 25 cc of whole blood labelled with Tc-99 HMPAO were reinjected into patients. Abdominal imaging was performed at a half hour postinjection and repeated at 2 to 4 hours postinjection. A positive study showed an increased isotope uptake in the right lower quadrant. Nineteen patients had histologically proven appendicitis. Three of these patients were excluded because they were operated on before scan completion. Thirteen of the remaining 16 patients with appendicitis had positive studies (false negative rate = 19%). All patients without appendicitis had either negative scans or scans that detected other intra-abdominal diseases, such as diverticulitis, tubo-ovarian abscess, or small bowel infarction (false positive rate = 0%). Overall, this Tc-99 HMPAO study had a sensitivity of 81 per cent, a specificity of 100 per cent and an overall accuracy of 89 per cent. The 4-hour Tc-99 HMPAO WBC scan is a useful, noninvasive test for confirming the clinical diagnosis of acute appendicitis, but it may prove more valuable as a diagnostic study to rule out appendicitis in patients that have abdominal pain of unclear etiology.

Can the psro's be cost effective? A study of the effect of the Commonwealth Health Agencies monitoring program on the length of stay of Medicaid patients in Massachusetts.

To analyze the effect of the Commonwealth Health Agencies Monitoring Program on the length of stay of a sample of Massachusetts Medicaid patients, we compared their experience with that of non-Medicaid patients. We found a consistently decreasing trend in the length of stay of Medicaid patients during the 2 1/2-year period studied. The average length of stay of Medicaid patients decreased by 11.9 per cent relative to the norm, whereas the non-Medicaid length of stay decreased by only 6.6 per cent. We infer that the Program may be credited within the 5.3 per cent differential decrease. The consistency and reliability of the data suggest that similar results may be extrapolated to the hospitals not sampled. We conclude that Professional Standards Review Organizations, of which this program was a precursor, can be cost effective, given an expanded review mandate and the application of suibable evaluative processes.