Outer diameter of the vermiform appendix: not a valid sonographic criterion for acute appendicitis in patients with cystic fibrosis

[Abdominal manifestations in cystic fibrosis : Clinical review]

Cystic fibrosis (CF) is the most common fatal autosomal recessive disease in the Caucasian population. A mutation in the cystic fibrosis transmembrane regulator protein (CFTR) gene leads to the production of abnormally viscous mucus and secretions in the lungs of these patients. A similar pathology also occurs in other organs. In the abdomen, among others the gastrointestinal tract, the pancreas, and the hepatobiliary system are affected. The involvement of the pancreas leads to its exocrine and endocrine insufficiency. Hepatic manifestations include hepatic steatosis, focal biliary and multilobular cirrhosis, and portal hypertension. Biliary complications include cholelithiasis, microgallbladder, and sclerosing cholangitis. In the gastrointestinal tract, complications such as the distal intestinal obstruction syndrome, invaginations, chronic constipation, wall thickening, and fibrosis in the colon may occur. An important renal manifestation is nephrolithiasis. With currently rapidly increasing life expectancy of patients with cystic fibrosis, complications of extrapulmonary cystic fibrosis manifestations including hepatic and gastrointestinal malignancy could be an increasing cause of morbidity and mortality of these patients. It is therefore important for radiologists to know and recognize these clinical patterns and to monitor these manifestations in follow-up exams. Previous therapy of extrapulmonary manifestations has been largely symptomatic. Fortunately, the new CFTR modulators seem to represent an effective causal therapeutic approach here.

Ultrasound of the pediatric appendix

Appendicitis is the most common pediatric surgical emergency. Ultrasound (US) receives the highest appropriate rating scale in children with right lower quadrant pain suspected to have appendicitis. The US exam of the appendix has improved since Puylaert pioneered the technique of graded compression in 1986. In this article, we review ultrasonography of the pediatric appendix as it pertains to the normal appendix, acute appendicitis and the different sonographic manifestations. We also briefly describe technical optimization of image acquisition, common pitfalls and differential diagnoses.

Acute appendicitis in young children less than 5 years: review article

Despite wide spread availability of sophisticated diagnostic imaging, acute appendicitis in pre-school children remains a diagnostic challenge. Most of these children present late, often with complications e.g. appendicular perforation, abscess formation and peritonitis and as result hospital stay is prolonged and is associated with increased morbidity and mortality.The purpose of this article is to review peculiar features of acute appendicitis in preschool children.

Cystic Fibrosis below the Diaphragm: Abdominal Findings in Adult Patients

Cystic fibrosis (CF) is the most common lethal autosomal recessive disease in the white population. Mutation of the CF transmembrane conductance regulator gene on chromosome 7 results in production of abnormally viscous mucus and secretions in the lungs of patients with CF. A similar pathologic process occurs in the gastrointestinal tract, pancreas, and hepatobiliary system. Inspissated mucus causes luminal obstruction and resultant clinical and radiologic complications associated with the disease process. Pancreatic involvement can result in exocrine and endocrine insufficiency, pancreatic atrophy, fatty replacement, or lipomatous pseudohypertrophy. Acute and chronic pancreatitis, pancreatic calcification, cysts, and cystosis also occur. Hepatic manifestations include hepatic steatosis, focal biliary and multilobular cirrhosis, and portal hypertension. Biliary complications include cholelithiasis, microgallbladder, and sclerosing cholangitis. The entire digestive tract can be involved. Distal ileal obstruction syndrome, intussusception, appendicitis, chronic constipation, colonic wall thickening, fibrosing colonopathy, pneumatosis intestinalis, gastroesophageal reflux, and peptic ulcer disease have been described. Renal manifestations include nephrolithiasis and secondary amyloidosis. The educational objectives of this review are to reveal the abdominal manifestations of CF to facilitate focused analysis of cross-sectional imaging in adult patients. Life expectancy in patients with CF continues to improve because of a combination of aggressive antibiotic treatment, improved emphasis on nutrition and physiotherapy, and development of promising new CF transmembrane conductance regulator modulators. As lung function and survival improve, extrapulmonary conditions, including hepatic and gastrointestinal malignancy, will be an increasing cause of morbidity and mortality. Awareness of the expected abdominal manifestations of CF may assist radiologists in identifying acute inflammatory or neoplastic conditions. (©)RSNA, 2015.

Cystic fibrosis: unenhanced CT description of the appendix in asymptomatic adults

OBJECTIVE

The purpose of this study was to describe the unenhanced CT appearance of the appendix in adults with cystic fibrosis.

SUBJECTS AND METHODS

Among adults with cystic fibrosis undergoing follow-up at our hospital, 71 patients (35 women, 36 men; mean age, 33 years; range, 18-59 years) without a history of appendectomy or current abdominal pain were prospectively included in this study and underwent unenhanced abdominopelvic MDCT. Two readers coded visualization of the appendix, measured the diameter of the appendix, and described the attenuation of its contents in relation to the intestinal wall. They also coded the presence of colonic wall redundancy, pancreatic fatty replacement, and cirrhosis. Lung transplant status and CFTR gene mutations were recorded. Analysis of variance, linear regression analysis, Student t test, and Pearson test were used.

RESULTS

The appendix was detected in all patients. The mean diameter was recorded as 10.6 ± 3.5 mm. The mean diameter was larger when the appendix contained hyperattenuating material (p = 0.001). There was no association between diameter and the other coded CT findings (p = 0.076-0.466), transplant status (p = 0.788), or CFTR mutation (p = 0.078). In 75% of the patients, the appendix contained hyperattenuating material with a higher proportion in homozygous ΔF508 mutation (p = 0.029) without any significant effect of the other CT features (p = 0.056-0.392), or transplant status (p = 1.000).

CONCLUSION

The appendix is larger in adults with cystic fibrosis than in those without it and appears hyperattenuating at unenhanced CT in 75% of patients, more commonly in those with ΔF508 homozygous mutation.

Acute appendicitis mimicking intestinal obstruction in a patient with cystic fibrosis

Cystic fibrosis (CF) is an inherited disease of the secretory glands caused by mutations of the cystic fibrosis transmembrane regulator (CFTR) gene. The clinical manifestations of CF are repetitive lung infections, biliary cirrhosis, pancreatic abnormalities, and gastrointestinal disorders. We report a 21-year-old Taiwanese man with CF who had abdominal pain for 2 days. The diagnosis of CF had been confirmed by peripheral blood analysis of the CFTR gene 5 years before admission. He presented to the emergency department with nausea, vomiting, abdominal distension, and crampy abdominal pain, which is atypical for acute appendicitis. The physical examination and a series of studies revealed intestinal obstruction, but acute appendicitis could not be ruled out. After conservative treatment, together with empiric antibiotics, the refractory abdominal pain and leukocytosis with a left-shift warranted surgical intervention. A diagnostic laparoscopy revealed a swollen, hyperemic appendix, a severely distended small intestine, and serous ascites. The laparoscopic procedure was converted to a laparotomy for open disimpaction and appendectomy. He was discharged on the eighth postoperative day. The histologic examination of the appendix was consistent with early appendicitis. In conclusion, acute abdominal pain in adult CF patients is often associated with intestinal obstruction syndrome. The presentation of concurrent appendicitis may be indolent and lead not only to diagnostic difficulties, but also a number of therapeutic choices.

US examination of the appendix in children with suspected appendicitis: the additional value of secondary signs

This study evaluated the additional value of secondary signs in the diagnosing of appendicitis in children with ultrasound. From May 2005 to June 2006, 212 consecutive paediatric patients with suspected appendicitis were examined. Ultrasonographic depiction of the appendix was classified into four groups: 1, normal appendix; 2, appendix not depicted, no secondary signs of appendicitis; 3, appendix not depicted with one of the following secondary signs: hyperechoic mesenteric fat, fluid collection, local dilated small bowel loop; 4, depiction of inflamed appendix. We classified 96 patients in group 1, 41 in group 2, 13 in group 3, and 62 in group 4. Prevalence of appendicitis was 71/212 (34%). Negative predictive values of groups 1 and 2 were 99% and 100%, respectively. Positive predictive values of groups 3 and 4 were 85% and 95%, respectively. In groups 3 and 4, hyperechoic mesenteric fat was seen in 73/75 (97.3%), fluid collections and dilated bowel loops were seen in 12/75 (16.0%) and 5/75 (6.6%), respectively. This study shows that in case of non-visualization of the appendix without secondary signs, appendicitis can be safely ruled out. Furthermore, secondary signs of appendicitis alone are a strong indicator of acute appendicitis.

Sonographic appearance of the normal appendix in adults

OBJECTIVE

To evaluate the sonographic visualization of the normal adult appendix, a large series of sonographic images from consecutive asymptomatic patients was analyzed.

METHODS

A total of 788 consecutive adult patients (402 male and 386 female; median age +/- SD, 51.1 +/- 17.2 years; range, 16-91 years) were examined by appendiceal transabdominal sonography with tissue harmonic imaging. The detection rate, outer appendiceal diameter, intraluminal content, and location of the appendix were estimated. The overall normal appendix was separated into appendix-visualized and appendix-not-visualized groups, which were then examined for the relationship with abdominal wall thickness, body mass index (in kilograms per square meter), age, and sex.

RESULTS

The normal appendix was detected in 388 (49.2%) of 788 patients. The outer appendiceal diameter +/- SD was 4.27 +/- 1.2 mm (range, 1.0-11.1 mm). In 291 (75%) of the 388 patients, appendices could be depicted in the intra-luminal gas during sonography. The location of the appendix was classified according to the appendiceal tip, which was found to be abdominal in 37 (9.5%), pelvic in 291 (75%), retrocecal in 23 (6.0%), and a midline extension in 37 (9.5%). In both body mass index and abdominal wall thickness, significant differences were found between appendix-visualized and appendix-not-visualized cases (P < .05). There was no significant difference in age (P = .37) or sex (P = .23) between appendix-visualized and appendix-not-visualized cases.

CONCLUSIONS

The results show that the normal adult appendix can be revealed by sonographic visualization in a large series of asymptomatic patients.