A Case Series of Appendicitis and Pseudo-appendicitis in a Paediatric Intensive Care Unit.

Introduction: Appendicitis is a common childhood condition that can be diagnostically challenging. Severe cases may necessitate support in the critical or intensive care unit. These "critical appendicitis diagnoses" have rarely been described.

Case Description: We retrospectively reviewed the Paediatric Intensive Care Unit (PICU) database of the Hong Kong Children's Hospital and identified cases of suspected and confirmed appendicitis. Clinical features, radiologic findings and final diagnosis of each case were summarized and reported in this case series. We review six anonymized cases of appendicitis managed in a PICU to illustrate the different age spectrum and clinical manifestations of the condition. Rupture of the inflamed appendix, peritonitis and pancreatitis were some of the complications encountered. Crohn's disease was found in one case as an underlying diagnosis. Also, one girl clinically diagnosed with appendicitis was found to be a case of ruptured hepatoblastoma with no appendicitis (i.e., pseudoappendicitis).

Conclusion: Prompt diagnosis, surgical removal of the inflamed appendix, and use of appropriate antimicrobials when indicated are essential in reducing mortality and morbidity associated with severe appendicitis. Significant premorbid conditions such as acute myeloid leukemia, Mitochondrial Encephalopathy Lactic Acidosis Syndrome (MELAS), inflammatory bowel disease and complications may be present in patients needing intensive care as is illustrated in the present cases. Pseudoappendicitis is an important differential diagnosis. Imaging is crucial and useful in establishing and confirming the diagnosis of appendicitis and pseudo-appendicitis in these PICU cases.