Distinct sonographic features of acute appendicitis in sickle cell disease.

BACKGROUND AND OBJECTIVES

The purpose of this study was to report sonographic findings of appendicitis in patients with positive screening tests for sickle cell compared to normal control patients.

DESIGN AND SETTING

A retrospective study of the medical records of 396 patients who underwent appendectomy during a 3-year period from March 2005-2008.

PATIENTS AND METHODS

The study included 216 males and 180 females, whose ages ranged from 7 to 55 years. Four patients (0.9%) had sickle cell disease (SCD), 101 had sickle cell trait (SCT) (25%) and 291 (74%) patients were without sickle cell anemia (control group).

RESULTS

Positive sonographic findings of appendicitis were identified in 95 (90%) SCT patients and in 253 (87%) control patients. The mean maximal mural thickness was higher in sickle cell patients (4.5 [1.4] mm) in comparison with the control group (3.0 [2.2] mm) (P < .0001). Appendicolith was significantly detected in 53% of the control group and in 8.5% of the sickle cell group (P < .0001). Color Doppler showed hypervascularity in 72% of patients with appendicitis in the control group with a significant difference compared to only 12 cases (11%) of SC patients (P < .05). Ultrasonography findings suggesting perforation were found in 35 sickle cell patients and in 75% (3 of the 4 patients) with SCD. Findings suggesting perforation were found only in 49 patients (17%) of the control group. Perforated appendix was significantly higher in sickle cell patients in preoperative US and intraoperatively (P < .05)

CONCLUSION

Positive sonographic findings of appendicitis in sickle cell patients are different from the general population. These findings include mural thickening with a low incidence of appendicolith and wall hypervascularity. Also sonographic features of perforation in sickle cell patients are more common suggesting a need for more urgent operative intervention.