Neostigmine for the treatment of acute colonic pseudo-obstruction (ACPO) in pediatric hematologic malignancies

Abstract

Background: Acute colonic pseudo-obstruction (ACPO) refers to dilatation of the colon and decreased bowel motility without evidence of mechanical obstruction. Neostigmine, an acetylcholinesterase inhibitor, has been used in patients in whom supportive therapy failed to resolve ACPO. Here, we report the results of administering neostigmine to treat ACPO in children with hematologic malignancies.

Methods: Between September 2005 and December 2009, 10 patients (8 male and 2 female) were diagnosed with ACPO at the Department of Pediatrics, Catholic University of Korea. Diagnosis of ACPO was based on typical clinical features as well as colonic dilatation found on abdominal CT imaging. Neostigmine was administered subcutaneously at a dosage of 0.01 mg/kg/dose (maximum 0.5 mg) twice daily for a maximum of 5 total doses. ACPO was determined to be responsive to neostigmine if the patient showed both stool passage and improvement of clinical symptoms.

Results: The study group included 8 acute lymphoblastic leukemia patients, 1 patient with malignant lymphoma, and 1 patient with juvenile myelomonocytic leukemia. The median age at ACPO diagnosis was 8.5 years (range, 3-14). Overall, 8 patients (80%) showed therapeutic response to neostigmine at a median of 29 hours after the initial administration (range, 1-70). Two patients (20%) showed side effects of grade 2 or above, but none complained of cardiovascular symptoms that required treatment.

Conclusion: In this study, ACPO was diagnosed most often in late-childhood ALL patients. Subcutaneous neostigmine can be used to effectively treat ACPO diagnosed in children with hematologic malignancies without major cardiovascular complications.

Keywords: Acute colonic pseudo-obstruction; Children; Hematologic malignancies; Neostigmine.

Fig. 1

An 11-year-old male patient diagnosed with Philadelphia chromosome-positive ALL failed to pass stools for 157 hours before an abdominal CT was undertaken. Initial imaging showed massive colonic dilatation and fecal impaction consistent with ACPO, with the maximum diameter of the ascending colon measuring approximately 6.7 cm (A). Four hours after imaging, the patient was started on subcutaneous neostigmine, which resulted in stool passage 1 hour later. The patient received 1 more infusion for rapid amelioration of symptoms. Follow-up imaging taken 7 days later showed improvement in both colonic dilatation and fecal loading with a decrease in the maximum diameter of the ascending colon to 4.8 cm (B).