Complicated Appendicitis With Unusual Complication: Appendicovesical Fistula
28-year-old man presented with the right lower abdominal pain and low-grade fever for 10 days before admission. His medical history was unremarkable. The physical examination disclosed a tender mass over the right lower quadrant of abdomen without rebound pain or muscle guarding. Laboratory test showed an elevation of white blood cell count (19,000/mL) and C-reactive protein (5.3 ng/dL). Abdominal computed tomography (CT) revealed the dilatation of appendix with appendiceal mass formation (Figure 1A, arrow). Under the impression of ruptured appendicitis with appendiceal mass formation, he admitted to our hospital for treatment. Initial nonsurgical treatment with intravenous broad-spectrum antibiotics with percutaneous drainage of abscess was given. The symptoms completely resolved, and the blood tests of white blood cell count and C-reactive protein were within the normal limit. He was out of hospital 7 days later and received a routine follow-up in outpatient clinic. Unfortunately, intermittent low-grade fever, frequency of urination and pyuria developed about 21 days later. Physical examination revealed right lower quadrant abdominal tenderness without rebound pain. His blood tests reported high white blood cell count (17,500/mL) and C-reactive protein (7.6 ng/dL). Also, pyuria and growth of Escherichia Coli were found in his urine analysis. Repeated abdominal CT scan showed progression of appendiceal abscess and wall thickening of urinary bladder (Figure 1B, arrow). With an impression of appendicovesical ﬁstula (AVF), surgical intervention with exploratory laparotomy was performed. Intraoperative cystoscopy discovered a small opening over the right lateral wall of bladder dome with continuous pus discharge. Appendectomy and partial cystectomy with an Endo-GIA stapler (Ethicon Endo-Surgery, Cincinnati, OH) were performed. The postoperative course was uneventful. The histopathological examinations revealed acute inﬂammation change of appendix and bladder with a small caliber ﬁstula tract between them. The diagnosis of AVF was conﬁrmed. Acute appendicitis is the most common disease in acute abdomen. The treatment for acute appendicitis usually requires surgical intervention. Delayed treatment may carry the risk of perforation and increase the surgical morbidity and mortality rates. However, about 25% of patients presented with perforated appendicitis at the time of diagnosis, and in 2% to 6% of patients, will develop appendiceal mass.1 Currently, treatment of appendiceal mass using broad-spectrum antibiotics with or without percutaneous drainage followed by interval appendectomy is favored by most surgeons. Initial nonsurgical treatment is successful in most patients and is associated with lower complication rate compared with immediate appendectomy.2 The failure rate of nonsurgical treatment is lower, and most of them are associated with abscess diameter .4 to 5 cm.3 In our case, the abscess diameter is about 3.5 cm. More recently, the necessity of interval appendectomy remains controversial. The risk of recurrence and missing or delaying diagnosis of appendicular malignancy are the major concerns over the use of routine interval appendectomy. The recurrent rate after successful conservative treatment is 3% to 25% and is often associated with appendicolith.
FIGURE 1. (A) Abdominal computed tomography scan showed ruptured appendicitis with periappendiceal inflammatory mass formation (arrow). (B) Repeated abdominal computed tomography scan demonstrated wall thickening of urinary bladder with a tubular-like structure formation (arrow).
Malignancies of appendix are extremely rare, and the incidence is about 0.9% to 1.4% in the United States. In nonsurgical patients, the need of interval appendectomy may be debate, the risk of recurrence should be informed especially in cases with appendicolith and careful follow-up with imaging are necessary. AVF is a very rare complication of complicated appendicitis. It may be produced from the inﬂammatory condition between the appendix and bladder, causing fusion, necrosis and ﬁnally ﬁstula formation. In addition to appendicitis, AVF may result from cystic ﬁbrosis, Crohn’s disease, appendicular malignancy, neuroma, villous adenoma and radiation. To the best of our knowledge, only 116 cases of AVF have been reported in the literature.4 However, AVF developed from appendiceal mass after successful nonsurgical treatment is the ﬁrst case report. Male is more predominant than female because of the interposition of uterus between the appendix and bladder. The clinical manifestation of AVF is predominantly the urological symptoms, including lower abdominal pain, dysuria, pyuria and frequency. The diagnosis of AVF is usually difﬁcult. Comparing to other diagnostic tools, abdominal CT has been recognized as the most useful tool.5 Surgical treatment with appendectomy and repair of the bladder is usually necessary in most patients. Although initial nonsurgical treatment followed by interval appendectomy for appendiceal mass has been widely accepted by most physicians, the risk of such severe and rare complication of AVF should not be ignored.
*Chieh-Wen Lai, Jiann-Hwa Chen, Ming-Hsun Wu, Chuang-Wei Chen,
MD MD MD MD
Department of Surgery Buddhist Tzu Chi General Hospital Taipei Branch, Taipei, Taiwan *E-mail: [email protected]
The authors have no ﬁnancial or other conﬂicts of interest to disclose. REFERENCES 1. Nitecki S, Assalia A, Schein M. Contemporary management of the appendiceal mass. Br J Surg 1993;80:18–20.
The American Journal of the Medical Sciences
Volume 349, Number 4, April 2015
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4. García-Muñoz-Najar A, Carrión-Álvarez L, Medina-García M, et al. Appendicovesical ﬁstula treated with elective laparoscopic surgery [in Spanish]. Cir Cir 2013;81:344–7.
3. Oliak D, Yamini D, Udani VM, et al. Initial nonoperative management for periappendiceal abscess. Dis Colon Rectum 2001;44: 936–41.
5. Jarrett TW, Vaughan ED Jr. Accuracy of computerized tomography in the diagnosis of colovesical ﬁstula secondary to diverticular disease. J Urol 1995;153:44–6.
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