Rigler sign is a double wall sign suggesting pneumoperitoneum and intestinal perforation, and it needs emergency surgical treatment. Early diagnosis of intestinal perforation by clinical symptoms, presence of Rigler sign in abdominal radiography, and then early surgical treatment can reduce mortality. Here, we report a patient with Crigler-Najjar syndrome who underwent liver transplant and then developed posttransplant lymphoproliferative disease and received chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab. She was referred to the emergency department due to abdominal distension with positive Rigler sign in abdominal radiography; intraoperative findings revealed intestinal perforation. Pediatricians and surgeons should be aware of Rigler sign so that it is diagnosed early and emergency surgical treatment can be performed.
Key words : Abdominal radiography, Intestinal perforation, Pneumoperitoneum, Posttransplantation lymphoproliferative disorder, Rituximab
The Rigler sign, also known as the double wall sign, is present when air exists inside and outside the bowel loops, suggesting pneumoperitoneum.1,2 This sign may require emergency surgical intervention; therefore, it should be diagnosed on supine abdominal radiographs.3 Several causes for pneumoperitoneum include infection, trauma, medication, spontaneous, surgical manipulation, and diagnostic procedure.3 The causative factors are summarized in Table 1.3,4
Rituximab, a recombinant anti-CD20 monoclonal antibody, is used for the treatment of posttransplant lymphoproliferative disorder (PTLD). The use of rituximab has been associated with spontaneous gastrointestinal perforation and may be due to rapid lysis of tumor in the gastrointestinal tract. However, this complication is rare after use of rituximab.4
The radiographic findings of pneumoperitoneum include air under diaphragm, which is most common, and also Rigler sign and air around peritoneum, which is referred to as the football sign.2,3 Here, we present a case of intestinal perforation with positive Rigler sign.
A 28-month-old girl with known Crigler-Najjar syndrome underwent liver transplant 6 months earlier at an affiliated hospital of Shiraz University of Medical Sciences (Shiraz, Iran) in May 2014. She was on immunosuppressive drugs, including prednisolone and tacrolimus, and also ganciclovir prophylaxis. After she developed cervical and mesenteric lymphadenopathy 5 months after liver transplant, a lymph node biopsy was performed with pathologic report showing polymorphic lymphoproliferative disease. Her dose of immunosuppressive medications was reduced, and the patient received CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone) plus rituximab. Four days after receiving the first course of chemotherapy, she was referred to the emergency department due to abdominal pain and distension, bilious vomiting, and low-grade fever. Physical examination revealed a conscious patient with temperature of 37.9°C (orally), blood pressure of 75/55 mm Hg, generalized abdominal tenderness without rebound tenderness, and normal heart, lung, and nervous system examination.
Abdominal radiography showed increased lucency overlying the liver, the Rigler sign, air fluid levels within the bowel loops, and air under the diaphragm (Figure 1A and 1B). She underwent an operation and received broad-spectrum antibiotics. Intraoperative findings revealed multiple small bowel perforations and peritonitis; therefore, a small bowel resection was done. During follow-up, the patient died due to sepsis. It should be noted that written informed consent was taken from her parents before study.
The prevalence of PTLD, a severe complication after organ transplant, is about 6% after liver transplant.5 In our study case, intestinal perforation with Rigler sign occurred 4 days after administration of CHOP chemotherapy plus rituximab. Our case study had involvement of the gastrointestinal tract by PTLD. As described above regarding causes of pneumoperitoneum, it seems that the most probable cause of intestinal perforation in this case was necrotizing enterocolitis or secondary to medication, including rituximab and immunosuppressive agents.
In a report of Cornejo and associates, an adult patient with gastrointestinal PTLD presented with intestinal perforation 5 days after taking rituximab.4 Intestinal perforation mostly occurs between 1 and 6 days after infusion of rituximab.4 The mechanisms of this adverse effect are unknown, but the cytotoxic effects of rituximab may be the cause. This is a rare and fatal adverse effect of rituximab.4,6
Therefore, in patients with PTLD, especially with gastrointestinal involvement, the use of rituximab, because of its probable involvement with intestinal perforation, should be administered with caution, and abdominal pain should be considered as an alarming sign after its use. Supine abdominal radiography is an important inexpensive and available diagnostic procedure in these patients.
Air under the diaphragm on the right side of the abdomen is the most frequent sign of pneumoperitoneum; the second most common sign is Rigler sign, characterized by the presence of air in luminal and peritoneal sides of the bowel loop.1,2 Therefore, physicians must be familiar with Rigler sign, as illustrated in Figure 1, because accurate and early diagnosis of intestinal perforation by clinical symptom, presence of Rigler sign in abdominal radiography, and then early surgical treatment can reduce mortality. It is also recommended that, in PTLD patients with gastrointestinal involvement who are scheduled to take rituximab, the surgeon should be informed to be ready for complications.
Volume : 16
Issue : 3
Pages : 352 - 354
DOI : 10.6002/ect.2016.0006
From the 1Department of Pediatric Hematology and Oncology, the
2Medical Imaging Research Center, the 3Department of
Pediatric Gastroenterology and Hepatology, the 4Hematology research
Center, and the 5Department of Pharmacology, Shiraz University of
Medical Sciences, Shiraz, Iran
Acknowledgements: The authors declare that they have no sources of funding for this study, and they have no conflicts of interest to declare.
Corresponding author: Nader Shakibazad, Department of Pediatric Oncology, Amir Oncology Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
Phone/Fax: +98 713 632 3532
Table 1. Causes of Pneumoperitoneum
Figure 1. Rigler Sign in Abdominal Radiography