Radiol Oncol 2005; 39(1): 15-21. Ultrasound signs of acute appendicitis in children - clinical application Sandra Vegar-Zubović1, Lidija Lincender1, Salahudin Dizdarević2, Irmina Sefić1, Faruk Dalagija1 1Institute of Radiology, 2Pediatric Surgery, Clinical Center of University in Sarajevo, Bosnia and Herzegovina Background. Acute appendicitis is a leading cause of the abdominal pain in children that need an urgent surgical treatment. Neither of individually clinical variables doesn’t have a real discriminational nor pre-dictive strength to be used as the only diagnostic test. A goal of this study is to define ultrasound criteria of the acute appendicitis by appointing of ultrasound parameters for this pathological condition, determine the relation between ultrasound signs and pathohistological finding, determine the connection of several ultrasound signs with a degree of the inflammation of the acute appendicitis. Methods. In the prospective study with an ultrasound method we examine 50 patients with clinical signs of the acute abdomen. In these patients, the sonographic diagnosis is confirmed by the surgical finding, in fact with a pathohistological diagnosis. A basic, positive sonograph finding of the acute appendicitis was the identification of tubular, noncompresive, aperistaltic bowel which demonstrates a connection with coecum and blind terminal. In our work we analysed the lasting of the symptoms until the hospital intervention in patients stratified according to the pathohistological finding. We used ultrasound equipment- Toshiba Sonolayer with convex 3.75 MHz and linear 8 MHz probes. Results. From 8 ultrasound signs of the acute appendicitis, only an anterior-posterior (AP) diameter of ap-pendices, FAT (width of periappendicular fat tissue) and a peristaltic absence are positive ultrasound signs of the acute appendicitis. Appendicitis phlegmonosa is the most common pathohistological finding in our study (44%). Perforate gangrenous appendicitis and gangrenous appendicitis are represented in more than half of patients (30% + 22%), which suggests a long period of persisting symptoms until a hospital treat-ment. A statistic analysis shows a great possibility for using values of AP diameter, width of periapendicu-lar fat tissue, just like the values of mural thickness in the evaluation of the appendix inflammation level. Conclusions. Ultrasound is an absolute method of choice in the eventual doubt of the existing state of acute appendicitis, with 8 ultrasound signs that defined this pathological condition. AP appendix diameter, mural thickness and width of periapendicular fat tissue represents highly significant ultrasound criteria in the evaluation of the appendix inflammation level. Key words: appendicitis-ultrasonography; child Received 7 June 2004 Accepted 23 August 2004 Correspondence to: Sandra Vegar-Zubović, MD, Institute of Radiology, Clinical Center of University in Sarajevo, Bosnia and Herzegovina; E-mail: denin@ bih.net.ba 16 Vegar-Zubović S et al / Ultrasound and acute appendicitis in children Introduction Acute abdomen is characterized by appearing of a sudden pain in the abdomen with a dys-function; it appears suddenly and unexpec-tantly and it is caused with large number of changes on different abdomen organs. A clin-ical picture of the acute abdomen is one of the most divert and most complex conditions in the human body because of the beginning and course of the illness which is dependent o a large number of different organs in the abdomen. Acute appendicitis is a leading cause of an abdominal pain in children which demands an urgent surgical treatment. Clinical symptoms and signs depend, in the first place, on children’s age, as well as on the pathological phase of appendicitis during the clinical examine. Beside the abdominal pain the acute inflammation of appendix is char-acterized with nausea, vomiting, anorexia, fever, diarrhoea, constipation, face blushing and tachycardia. Little patients preferred ly-ing on the back in the supinatory position or on the right decubitus, quietly, because every motion causes pains. Cope made a list of 34 illnesses which lead to acute abdominal pains, and those conditions, according to signs and symptoms, which imitate the acute appendicitis. This list could be a longer, if we include immunodeficiency syndromes and another immunodeficiency states.1 The differential diagnosis of an abdominal pain is one of the fascinating, but mysterious questions for the clinical surgery. Reginald Fitz (1886) gave his own historical session de-scribing a new pathological entity - appen-dicitis. And after 100 years, the exact diagno-sis of this mysterious disease is still a huge problem.1,2 A diagnostic imaging of an acute abdominal pain in children is very hard, because lit-tle patients are not capable to give us relevant data. Besides, an acute, non-specific abdominal pain, which is very common in children, these little patients with an abdominal pain Radiol Oncol 2005; 39(1): 15-21. usually have symptoms that last longer than 24 hours (2/3 patients). If diagnosis and treat-ment are delayed, the morbidity and mortali-ty of little patients increase. A diagnosis of typical clinical picture of the acute appendici-tis is relatively easy, but in 30-45% of little pa-tients it is presented with atypical clinical signs and symptoms which implicates the ad-ditional diagnostic imaging.3,4 Neither diagnostic variable individually (clinical and laboratory parameters) doesn’t have significant discriminating nor predictive strength to be used as a relevant diagnostic test. There is a high risk of the incorrect diag-nosis in some populations, especially in chil-dren without the existence of a relevant diag-nostic test. The exact and prompt diagnosis is essential for minimizing of morbidity. The goal of a modern surgical approach es-sentially is the same as in the 19th century, but today it is focused between percent of false negative appendectomy and percent of perforation in the time of the surgical obser-vation. Introducing of ultrasound in the diag-nosis of acute appendicitis, as this study shows, represents our aspect in leading of a modern medical protocol for young patients in this condition. Methods In the prospective study we analysed the pos-sibilities of ultrasound in diagnosis of the acute appendicitis in children. The research compassed 50 children in age from 0 to 16 years in whom ultrasound find-ings are confirmed with an operative, respec-tively, with a pathohistological finding (verifi-cation). These patients are observed and treated in the Clinic for Children’s Surgery of Clinical Center Sarajevo initiated from Dom zdravlja Sarajevo. The study includes patients with both genders, with a clinical picture of the acute abdomen with its symptoms that occurred for the first time. Vegar-Zubović S et al / Ultrasound and acute appendicitis in children 17 All patients are initially examined by the children’s surgeon who, after clinical and lab-oratory findings, referred children to the ultrasound examination. After the examination of the pelvis minor abdomen - the area of a maximum pain which a patient pointed with his/her finger (self-lo-calisation) - the ileocoecal area was examined with a systematic ultrasound approach be-cause of the possibility of the aberrant locali-sation of appendix. A definition of the positive acute appen-dicitis sonograph finding was based on the identification of tubular, non-compressed, aperistaltic bowel which demonstrates a con-nection with caecum and clearly visible bow-el blind terminal. By a careful approach, on the basis of eight ultrasound signs of acute appendicitis, we determined a connection be-tween some US signs and a degree of the in-flammation of the acute appendicitis. In the study we tried to analyse the lasting of symptoms until the hospital intervention in pa-tients divided according to the pathohistolog-ical finding. All examinations were done with the ultrasound unit Toshiba Sonolayer SAL 77 with convex (3.7 MHz) and linear (8 MHz) probes. Little patients were coming to be ultrasound examined as the urgent cases during the day or in the evening hours after they had been examined by their surgeon. A dosed com-pression in the ileocaecal area with a linear probe enabled the approach of ultrasound waves by gaping bowels with its content. Patients can suffer moderate compression as long as it is gentle, and according to the in-tensity it is identical to moderate deep palpation of the physical examination. For the identification of appendix it is necessary to find essential constraints: identify coecum and right colon in the transversal and longi-tudinal plane, identify musculus psoas and external iliac artery, and also identify terminal ileum. Results Table 1 shows basic demographic data of all patients. There is no significant statistical dif-ference of the mean value (using age frequen-cies) between two groups of patients (p>0.05). Table 2 shows eight ultrasound signs of acute appendicitis that are individually analysed in each patient. Figure 1 shows pathohistological findings of the examined group of little patients. From these data we can see that appendicitis fleg-monosa is the most common pathohistologi-cal finding (44%) (Figures 2a, 2b). In more than half of examined patients gangrenous appendicitis and perforate gangrenous ap-pendicitis (30% + 22%) were found, which suggests a long existence of symptoms until the hospital treatment. Table 3 analysed the lasting of symptoms until the hospital inter- Table 1. Basic demographic data in the examined group of patients Group I Total Male Female Age interval N X S Sx Mediana 3-16 26 9.864 3.518 0.690 9.5 4-16 24 11.083 3.900 0.796 11.5 3-16 10.440 3.721 0.526 11 X2= 0.0801; p=0.777 Radiol Oncol 2005; 39(1): 15-21. 18 Vegar-Zubović S et al / Ultrasound and acute appendicitis in children Table 2. Ultrasound signs in the examined group of patients Anterior-posterior diameter (AP) Mural wall thickness (MWT) Air in lumen (AIR) Inflame surrounding fat tissue (FAT) Lack of Intra- peristaltic luminal appendicolitis Persistence of lymphonodes in appendix region Local pericoecal fluid in abdomen NegativeUS signs0 0 0 0 Uncertain signs 0 6 (12%) 10 (20%) 0 Positive US 50 44 (88%) 40 (80%) 50 (100%) signs (100%) 0 15 (30%) 4 (8%) 29 (78%) 0 9 (18%) 11 (22%) 0 50 (100%) 26 (52%) 35 (70%) 11 (22%) Table 3. Existing of symptoms until hospital intervention Appendicitis catharalis Appendicitis flegmonosa Appendicitis gangrenosa Appendicitis gangrenosa perforata N 2 22 11 15 Interval 4-8 4-48 10-48 14-72 X 6 20.091 24.909 34.067 S 2.828 12.641 12.661 19.073 Sx 2 2.695 3.817 4.925 Mediana 6 16 20 24 Mann-Whitney test t = 5.00 , p= 0.042 22%/^_l 30%N-_ 4% h ¦44% ¦ 1 ¦2 D3 D4 Figure 1. Patohistological findings in the examined group of patients. 1 apendicitis gangrenosa perforata; 2 apendicitis flegmonosa; 3 apendicitis catharalis; 4. apendicitis gangrenosa. vention in all patients divided according to the pathohistological finding. Using a suma range test we can see that 2/3 of patients with acute appendicitis have symptoms which last more than 24 h. There is a direct correlation between the percent of perforations and the period of lasting symptoms; and also time of delay of the hospital treatment and time of the observation before admitting to hospital have a significant influ-ence. In the following tables, using suma range test, we tested the possibility of using values Radiol Oncol 2005; 39(1): 15-21. Figures 2a, 2b. Appendicitis phlegmonosa. Vegar-Zubović S et al / Ultrasound and acute appendicitis in children 19 Table 4. Anterior-posterior (AP) diameter of appendix in the examined group of patients (n=48), except appen-dicitis catharalis (n=2) Appendicitis flegmonosa Appendicitis gangrenosa Appendicitis gangrenosa perforata N 22 11 Interval AP diameter 7-12 10-18 9-14 X 9.318 13.455 11.067 S 1.427 2.659 1.534 Sx 0.304 0.802 0.396 Mediana 9 13 11 T=-5,854; p<0,001 T=2.894; p=0,008 Mann-Whitney test (app.flegmonosa vs app. perforata gangrenosa) P=0,003 Table 5. Mural wall thickness (MWT) of appendix in the examined group of patients (n=48), except appen-dicitis catharralis (n=2) Pathohistological finding Appendicitis. flegmonosa Appendicitis gangrenosa App. gangrenosa perforata N 22 11 MWT interval 2.5-4 3-5 2.8-5 X 3.145 3.664 4.056 S 0.436 0.612 0.816 Sx 0.093 0.185 0.204 Mediana 3 3.5 4 p = 0.012* p = 0.217* Mann-Whitney test (app.flegmonosa vs. app. perforata gangrenosa) p = 0.001* Table 6. Inflame surrounding fat tissue (FAT) around appendix in the examined group of patients (n=48) except appendicitis catharralis (n=2) Pathohistological finding Appendicitis. flegmonosa Appendicitis gangrenosa App. gangrenosa perforata 22 11 MWT interval 7-13 9-15 11-20 X 10.045 12.182 14.200 S 1.430 2.272 2.426 Sx 0.305 0.685 0.626 mediana 10 12 14 p = 0.013 Mann-Whitney test (app.flegmonosa vs. app. perforata gangrenosa) p = 0.042 p < 0.001 Radiol Oncol 2005; 39(1): 15-21. 20 Vegar-Zubović S et al / Ultrasound and acute appendicitis in children of: Anterior-posterior diameter (AP), Mural wall thickness (MWT), Inflame surrounding fat tissue (FAT) (Tables 4, 5, 6) in estimating of degree of appendix inflammation. Statistic analysis shows a great potential and possibil-ities of using AP and FAT in estimation of the inflammation degree in everyday practice. A statistical analysis shows the limited possibil-ity of using mural wall thickness values in gangrenous appendicitis and perforate gan-grenous appendicitis. In that case we use oth-er ultrasound signs that can determinate these pathological conditions. Sensitivity of ultrasound method in our study is 85%. Discussion The incidence of appendicitis appearance is usually between 5-10 years of age. Homogeneity of the group is showed with mean value where it is proved that there is no significant difference in the examined age fre-quency (p> 0.05). Homogeneity of our group also showed that the appearance of acute ap-pendicitis will be most common in age be-tween 5 and 10 years, without gender pre-dominance. Until puberty, the incidence of appendicitis is the same at boys and girls, and in the puberty prevalence is in male population with rate 2:1.5 There is no significant connection between life style, taking some specific food or genetic predispose for arising of the acute inflammation of appendix.6 Until 1986, the conventional radiography, includ-ing standard abdomen radiography and iri-gography, represents the only radiological methods, beside clinical and laboratory find-ings, that tried to limit the differential diag-nosis of the acute appendicitis. Detailed clas-sifying of the clinical examination can in cer-tain percent reduced the differential diagno-sis and constrains it to possible acute appen-dicitis: pain migration to lower right quadrant, pain deterioration because of motion, cough, anorexia and vomiting and indirect Radiol Oncol 2005; 39(1): 15-21. tenderness (Rovsing sign). Children with an »uncertain« diagnosis deserved further diag-nostic imaging or observation depending to aspect and lasting of symptoms. High percent of acute gangrenous appen-dicitis and perforate gangrenous appendici-tis, which our study shows, suggests a long period of persisting symptoms until the hospital treatment. Unfortunately, only two pa-tients had appendicitis catharalis. Percent of perforations and complications of the acute appendicitis in children’s age is still very high. The reasons for that are because little patients don’t recognise and don’t show signs and symptoms of the disease, appearance of clinically atypical picture of the acute appen-dicitis, quick evaluation of disease in these patients, health ignorance of parents. Worell S et al. in its study on 200 patients offered on-ly four criteria for the analysis of acute ap-pendicitis: 1. visualisation of appendix, 2. an-terior-posterior diameter AP > 6 mm, 3. mural thickness of appendix MWT > 3 mm, 4. ap-pearance of complex mass in ileocaecal area. Because of limiting factors that characterized this study, its sensitivity was only 68%.7 Our study offered eight ultrasound signs of the acute appendicitis. Results showed that AP diameter, FAT and peristaltic absence are certain ultrasound signs of the acute ap-pendicitis, and also FAT and AP have a great potential in defining the appendix inflamma-tion degree, while MWT have a limited possi-bility in that case. According to the experi-ence in our study, in patients without the pos-sibility of visualisation of appendix, and with the appearance of good and clearly visible pericaecal fluid and changed pericaecal fat tissue, we can make a conclusion that it is perforate appendicitis. Most common mistakes in US imaging of appendicitis compassed the commutation be-tween appendix and terminal ileum, and also between normal and inflame appendix.8 Terminal ileum doesn’t rise from caecum base, doesn’t have blind terminal but shows Vegar-Zubović S et al / Ultrasound and acute appendicitis in children 21 very accelerating peristaltic, and in transversal scanning it is oval describing to appendix which is clearly round as a »target«. False negative results in the ultrasound examina-tion can appear in overweight patients and in atypical localisation of appendix.9 Conclusions The initiation of ultrasound in diagnostic im-aging of the acute abdomen allowed a high percent of diagnostic assurance in little pa-tients. With the experience true continuous work with an ultrasound technique and by understanding of criteria of acute appendici-tis, the improvement of diagnostic assurance can be achieved. The continuation of hospital observation and treatment increase the mor-bidity and mortality of patients with the acute abdomen. Concretely, the persistence of symptoms from beginning of the disease un-til the initial ultrasound examinations and surgical treatment is in a direct proportional relation with the degree of appendix inflam-mation. Anterior-posterior diameter (AP), mural thickness (MWT), periapendicular fat tissue width (FAT) represent highly reliable US signs in the evaluation of degree of the acute appendicitis inflammation. Ultrasound is a cheap method, without a harmful effect, quick and simple, and using a real-time interactive technique. The aim of a modern surgical approach is essentially the same as in the 19th century, but today, it is focused between the percent of false negative appendectomies and the one of the perforation during the time of the sur-gical observation. 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