Colosplenopleural fistula: An unusual colonic fistula in a 44-year-old male with Crohn's disease.

A 44-year-old male with a history of well-controlled human immunodeficiency virus disease and Crohn's disease presented with fever, cough, and left-sided chest pain with radiation to his back. His medical history was notable for a medically managed spontaneous microperforation of the colon at the splenic flexure 30 months prior, and recurrent left-lower-lobe pneumonia with empyema and a splenic abscess within the past 24 months. CT demonstrated a complex left pleural fluid collection with fistulous connection through the spleen and into the large bowel. The patient tolerated a diverting loop ileostomy without complications and was discharged home with plans for resection of the fistulous tract and splenectomy in several months.

Case report

A 44-year-old African American male presented with fever, cough, and left-sided chest pain radiating to his back. He had a history of human immunodeficiency virus (HIV) disease and was well controlled on efavirenz-emtricitabine-tenofovir (Atripla). He had not had any reported opportunistic infections; his CD4 count two months before admission was 636 cells/μL. Two years ago, he was diagnosed with Crohn's disease but was not currently on any maintenance therapy. He was passing two stools daily without blood, melena, or mucus, and was not having any abdominal pain.

Two and a half years before this admission, he presented with a spontaneous localized colonic perforation at the splenic flexure that was medically managed with ciprofloxacin and metronidazole. His symptoms improved, but he required outpatient treatment for left-lower-lobe pneumonia. Six months later, he was admitted with a loculated left-lower-lobe hydro-pneumothorax that required video-assisted thorascopy (VATS) with washout and decortication. Cultures grew Escherichia coli. A splenic laceration was appreciated on CT imaging and was managed conservatively. No entero-pleural fistulas were seen. He was re-admitted seven months before the present admission with a recurrent left-lower-lobe empyema associated with a splenic abscess, a previously noted splenic laceration, and a diaphragmatic injury. He underwent interventional-radiology-guided percutaneous drainage of the empyema, and beta-hemolytic Streptococcus and Escherichia coli were cultured. He recovered after completing a prolonged course of ceftriaxone and clindamycin.

At admission, he was febrile with unstable vital signs that improved with fluid resuscitation, clindamycin, and ceftriaxone. He had diffuse bilateral rhonchi and diminished breath sounds in the right posterior lobe, with a cough productive of yellow-green sputum. Laboratory data revealed a leukocytosis (WBC 14,300 cells/uL, 82.9% segmented neutrophils) and an elevated ESR (75 mm/hr) and CRP (158 mg/L); his basic metabolic profile and liver panel were within normal limits. CT demonstrated loculated fluid and air in the left basilar pleural space (Fig. 1A; thick arrow), communicating with the colon at the splenic flexure (thin white arrow) through a fistulous connection in the spleen (curved arrow).

Figure 1A

CT demonstrates loculated fluid and air in the left basilar pleural space (thick arrow), communicating with the colon at the splenic flexure (thin white arrow) through a fistulous connection in the spleen (curved arrow).

The colosplenopleural fistula is appreciated on all images as a band of low attenuation running obliquely through the spleen (Fig. 1B; thick arrow). This band likely represents infected fluid and is seen on the sagittal CT image (Fig. 1B) to be continuous with the pleural space adjacent to focally consolidated lung (Fig. 1B, curved arrow). More medially (Fig. 1C), the low-attenuation fistulous tract through the spleen can be seen with direct extension to the colon at the splenic flexure (Figure 1A, Figure 1C, white arrow). Several foci of gas (asterisk) are seen within the tract at this junction and serve as indirect evidence of a fistulous connection. The patient tolerated a diverting loop ileostomy without complications and was discharged home. He is scheduled for resection of the fistulous tract and splenectomy.

Figure 1B

The colosplenopleural fistula band likely represents infected fluid and is seen on the sagittal CT image to be continuous with the pleural space adjacent to focally consolidated lung (curved arrow).

Figure 1C

More medially, the low-attenuation fistulous tract through the spleen can be seen with direct extension to the colon at the splenic flexure (white arrow).

Discussion

Approximately 20-40% of patients with Crohn's colitis will develop either external or internal fistulas in their lifetime (1). The most common internal fistulas are ileosigmoid, although colovaginal and colovesicular fistulas are well described (1, 2). In rare instances, colosplenic and colobronchial fistulas have been described in Crohn's disease (2, 3). To our knowledge, a fistula extending from the colon through the spleen and into the pleural space has not been previously described in Crohn's disease.