technetium-tc-99m-exametazime and Abdominal-Pain

The case of an 11-year-old boy with recurrent abdominal pain is presented. Physiological findings were found normal during a clinical investigation, as well as many laboratory tests, ultrasonography and CT of abdomen. Only a high level of sedimentation rate and the focus of increased activity in the sacral region on scintigraphy using 99mTc-HMPAO (hexamethypropyleneaminooxime) labelled leukocytes were found. The other findings on bone scintigraphy, X-ray and MRI led to a deflection of the correct diagnosis. The real culprit proved to be an ingested foreign body (a piece of a wooden skewer) that the patient failed to reveal.

Topics: Abdomen; Abdominal Pain; Child; Diagnosis, Differential; Foreign Bodies; Humans; Inflammation; Leukocytes; Magnetic Resonance Imaging; Male; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Ultrasonography

Topics: Abdominal Abscess; Abdominal Pain; Adult; Crohn Disease; Diagnosis, Differential; Female; Humans; Incidental Findings; Leukocytes; Nocardia Infections; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Topics: Abdominal Pain; Aneurysm, Infected; Colitis; Humans; Leukocytes; Middle Aged; Radiography; Radionuclide Imaging; Radiopharmaceuticals; Salmonella Infections; Technetium Tc 99m Exametazime

We evaluated Tc-99m-labeled anti-CD15 immunoglobulin M monoclonal antibody (LeuTech) for scintigraphic detection of acute appendicitis in patients with an equivocal clinical presentation. LeuTech avidly binds to circulating and sequestered human polymorphonuclear neutrophils in vivo eliminating the need for in vitro cell labeling and the risks of blood handling. We studied 99 patients to evaluate the safety and efficacy of LeuTech imaging. Serial dynamic and static planar images were acquired for up to 3 hours after the intravenous administration of 10 to 20 mCi of Tc-99m LeuTech. Scans were read as positive or negative for acute appendicitis or other intra-abdominal infection. The institutional diagnosis was established by surgery and histopathology of the appendix, results of other diagnostic studies, or 2-week clinical follow-up. Scans were positive for appendicitis in 39 of 40 patients with appendicitis at surgery (sensitivity 98%) and negative for appendicitis in 49 of 58 patients without appendicitis (specificity 84%). One was lost to follow-up. Accuracy, positive predictive value, and negative predictive value were 90, 81, and 98 per cent respectively. In patients with appendicitis and positive scans more than 50 per cent of the images were positive at 4 minutes, and all were positive by 1 hour. Mean time of first positive image was 15 minutes. There were no serious adverse reactions. We conclude that LeuTech imaging is a highly sensitive test for detection of appendicitis in equivocal cases. There are advantages of this agent over the other currently used radiotracers in terms of convenience and time to diagnosis particularly the rapidity with which acute appendicitis will be seen on the images.

Topics: Abdomen; Abdominal Pain; Acute Disease; Antibodies, Monoclonal; Appendectomy; Appendicitis; Follow-Up Studies; Humans; Immunoglobulin M; Injections, Intravenous; Lewis X Antigen; Neutrophils; Predictive Value of Tests; Radioimmunodetection; Radiopharmaceuticals; Safety; Sensitivity and Specificity; Technetium Tc 99m Exametazime

We used a radiolabeled white blood cell (WBC) scan as an adjunct to diagnose appendicitis in 100 children with equivocal signs or symptoms of appendicitis. WBC separation and labeling took 2 hours. Patients were imaged up to 3 hours after injection of labeled Tc-WBC. Accuracy was established in all 100 children by histopathological findings, medical records and follow-up interviews. Scans were positive in 40 and negative in 60. Positive scans averaged 76 +/- 40 minutes after injection (mean +/- SD); negative scans required 150-180 minutes. Tc-WBC scan correctly identified appendicitis in 36 of 37 children (sensitivity, 97%) and correctly excluded appendicitis in 59 of 63 (specificity, 94%). The false negative scan occurred in a patient whose perforated appendix was discovered at operation 3 days following the scan. Accuracy of the examination was 95 per cent, with a positive predictive value of 90 per cent and a negative predictive value of 98 per cent. The negative laparotomy rate for the entire group was 4 per cent. Tc-WBC imaging is an accurate, noninvasive test for ruling out appendicitis in children with right lower quadrant abdominal pain and equivocal presentation, although positive scans require more clinical judgment. The high sensitivity and negative predictive value suggest its potential for screening and discharging children from the emergency department.

Topics: Abdominal Pain; Acute Disease; Adolescent; Appendicitis; Child; Child, Preschool; Diagnosis, Differential; Emergency Service, Hospital; False Negative Reactions; Female; Follow-Up Studies; Humans; Injections, Intravenous; Interviews as Topic; Intestinal Perforation; Laparotomy; Leukocytes; Male; Medical Records; Mesenteric Lymphadenitis; Patient Discharge; Predictive Value of Tests; Prospective Studies; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Time Factors

To determine the accuracy and reliability of a labeled leukocyte imaging technique in the early diagnosis of pediatric appendicitis, we prospectively studied patients presenting to the pediatric emergency department with abdominal pain suggestive of appendicitis. Patients scheduled for urgent laparotomy were excluded, as were postmenarchal females. Blinded interpretations by two independent radiologists were compared with surgical findings, if managed operatively, or with discharge diagnoses and three week follow-up, if managed medically. Twenty-three children underwent technetium-99m hexamethylpropylene amine oxime (HMPAO) leukocyte scintigraphy. Seven had pathologically proven appendicitis, with false negative interpretations made in three and five cases by the two radiologists. Sixteen patients had prompt resolution of symptoms; however, scintigraphic abnormalities were identified in 10 and seven cases by the two radiologists. Resulting sensitivity, depending on the individual reader, ranged from 29 to 57%, with specificity 38 to 56%, positive predictive value 22 to 29%, negative predictive value 64 to 67%, and accuracy 43 to 48%. Interrater reliability for agreement on the scintigraphic diagnosis of appendicitis was poor (kappa = 0.38). Technetium-99m HMPAO leukocyte scintigraphy was neither accurate nor reliable as a diagnostic tool in a subgroup of pediatric patients with an initial clinical presentation equivocal for appendicitis. This finding contradicts previously published experience using similar scintigraphic techniques.

Topics: Abdominal Pain; Adolescent; Appendicitis; Child; Child, Preschool; Diagnosis, Differential; Female; Humans; Leukocytes; Male; Observer Variation; Organotechnetium Compounds; Oximes; Prospective Studies; Radiography; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Exametazime

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.. 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.. 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.. 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.

Topics: Abdominal Pain; Acute Disease; Adult; Appendicitis; Diagnosis, Differential; Diverticulitis; Female; Follow-Up Studies; Humans; Inflammation; Leukocytes; Male; Organotechnetium Compounds; Oximes; Prospective Studies; Radionuclide Imaging; Sensitivity and Specificity; Single-Blind Method; Technetium Tc 99m Exametazime; Ultrasonography

Topics: Abdominal Pain; Adult; Female; Fever; Humans; Leukocytes; Organotechnetium Compounds; Oximes; Radionuclide Imaging; Technetium Tc 99m Exametazime; Urinary Retention