The Clinical Conundrum of Diagnosing Children with Fever and Pain Abdomen Amidst a Clustering of Pims-Ts Cases in the Omicron Dominant Era

ABSTRACT

Aims The Omicron variant of SARS-CoV-2 variant has rapidly spread in the UK since December 2021.There was a significant increase in the number of children testing positive for SARS-CoV-2 in December 2021 in the population served by this DGHS. A clustering of cases of PIMS- TS was noted in the last week of December 2021 and the first week of January 2022. The focus of this descriptive study of PIMS-TS patients from a single centre is to report the clustering of cases in the Omicron dominant period and to describe the dilemma of managing children who present with fever and pain abdomen. Methods Children confirmed to have PIMS-TS and one child who presented mimicking PIMS -TS were identified, their investigations, treatment and outcomes were reviewed Results A cluster of 6 children diagnosed as PIMS -TS presented from the 29th of December 2021 to the 8th of January 2022.The mean age of patients was 9.3 years. There was ethnic variation with 3 Asian, 2 Afro Caribbean and one White child. Mean CRP was 226( range 85-400). All children presented with fever of more than 3 days.3 children presented with partial Kawasaki features, 2 children were treated for shock and 2 children presented with pain abdomen and fever. A 15 year old presented with fever, pain abdomen and tenderness in the right iliac fossa. He was managed initially as appendicitis. Blood markers for PIMS-TS were significantly raised along with raised CRP of 204. CT abdomen showed ileitis. His NPA RT- PCR was positive for SARS-CoV-2. He continued to have high fever, a diagnosis of PIMS-TS was made. There was significant improvement in both clinical condition and biochemical markers following IV Methylprednisolone. On the same day a 11 year old presented with fever, pain abdomen and increased irritability. He had global developmental delay and was PEG fed. He was initially managed as PIMS-TS then diagnosed to have appendicitis. CT abdomen showed a perforated appendix. He had a good outcome after surgery Conclusion The clustering of cases of PIMS- TS may be specific to this geographical area and multi-ethnic population following a period of high SARS-CoV-2 prevalence in the community with the Omicron variant. PIMS-TS can closely mimic appendicitis and distinguishing between both can be difficult. In the first child, CRP was unusually high (202) which helped in making a diagnosis avoiding unnecessary surgery. In the second child clinical acumen and involvement of multiple specialist teams helped in making the diagnosis of appendicitis. The global developmental delay and the child being nonverbal proved to be confounding factors. Cases of PIMS-TS can have bowel inflammation, it is also possible that COVID-19 can occur with other pathologies. Radiology findings need to be interpreted with the clinical picture. Clinical acumen, considering a range of differentials working closely with other specialities enables us to make a correct diagnosis for the unwell child who presents in the COVID-19 pandemic.