Pediatric appendicitis in "real-time": the value of sonography in diagnosis and treatment.

OBJECTIVES: To determine the accuracy of sonography in the diagnosis of clinically equivocal appendicitis, and to identify the factors leading to an inaccurate ultrasound diagnosis. The impact of sonographic findings on clinical management and outcome of children with appendicitis is examined. METHODS: We performed a retrospective review of 317 children who attended the emergency department (ED) of a children's hospital for acute abdominal pain for which acute appendicitis was the main differential diagnosis. They had ultrasound because the diagnosis was uncertain clinically. RESULTS: The positive predictive value of ultrasound for appendicitis was 0.92, and the negative predictive value was 0.88. The sensitivity and specificity could not be determined because there were 43 patients with equivocal ultrasound results. The pitfalls hindering the accuracy of ultrasound diagnosis included a high incidence of perforated appendicitis at presentation, the retrocecal appendix, and other technical factors such as abdominal guarding, excessive bowel gas, obesity, inadequate bladder filling, and the uncooperative patient. When ultrasound findings were combined with clinical judgment in clinical management, there were only five cases of non-therapeutic laparotomy and eight cases of delayed surgery due to missed diagnosis in our cohort. CONCLUSIONS: Ultrasound is a useful for the evaluation of acute abdominal pain in children. However, in the setting of a pediatric hospital ED, the accuracy of ultrasound and its ability to improve early hospital triage may be reduced. Repeated clinical review is still essential and in selected cases, appendiceal CT scan may be required to guide therapeutic decision making.

MMPI-2 fake-bad scales: an attempted cross-validation of proposed cutting scores for outpatients.

Minnesota Multiphasic Personality Inventory-2 (MMPI-2) results were compared in 118 psychiatric outpatients given standard instructions, instructions to exaggerate their problems, instructions to feign a disorder they did not have, or instructions to feign global psychological disturbance. The groups were comparable on demographic, occupational and diagnostic characteristics as well as intake MMPI-2 results. Experimental MMPI-2 results showed that clinical scales were generally elevated in the feigning groups, with only modest differences across dissimulating instruction sets. The feigning groups had reliably higher scores than controls on all overreporting indexes examined, although no significant differences between feigning groups were present for overreporting indexes. Classification rates using previously proposed cutting scores for outpatients on individual feigning indexes showed near perfect specificity, but low to at best moderate sensitivity. Multiple regression analyses indicated that Gough's (1954) Dissimulation Scale (Ds2) was most strongly related to feigning status, and no other feigning scale contributed a significant increment in predictive power once Ds2 was entered.