PT - JOURNAL ARTICLE AU - Paul Anthony Heaton AU - Krzysztof Piotr Zaborowski AU - Stephen David Holwill AU - Graham David Merrick AU - Siba Prosad Paul TI - Painless expanding facial swelling AID - 10.1136/archdischild-2020-320371 DP - 2022 Apr 01 TA - Archives of disease in childhood - Education & practice edition PG - 121--123 VI - 107 IP - 2 4099 - http://ep.bmj.com/content/107/2/121.short 4100 - http://ep.bmj.com/content/107/2/121.full SO - Arch Dis Child Educ Pract Ed2022 Apr 01; 107 AB - Case history A previously healthy 11-year-old girl sustained a mosquito bite on her right cheek while on holiday in rural Bangladesh. A painless lump developed at the site, and over the ensuing 2 months gradually expanded. She was otherwise completely asymptomatic; there was no family history of note. On examination, there was obvious swelling affecting the right cheek and visible abnormality of the upper gum with displacement of the right upper central incisor (figure 1).Figure 1 Swelling of gum and displacement of tooth.The facial swelling measured 4×5 cm, was firm to touch, non-fluctuant, painless and non-tender; no other abnormalities were present. Blood results at presentation are shown in box 1.Box 1 Blood results at presentationHaemoglobin 132 g/L (115–155).White cell count 6.92×109/L (5.0–13.0).Platelets 359×109/L.Erythrocyte sedimentation rate 7 mm/hour (0–12).C-reactive protein 2 mg/L (0–10).Calcium 2.32 mmol/L (2.1–2.6).Alkaline phosphatase 242 u/L (78–213).Lactate dehydrogenase 391 u/L (250–450).MRI scan (figure 2) showed well-defined unilocular hyperintense signal cystic lesion measuring 40×38×40 mm involving right-sided alveolar process of maxilla completely filling the right maxillary sinus.Figure 2 MRI showing right-sided cyst arising from maxilla.Question 1 What is the most likely diagnosis?Burkitt’s lymphomaEwing’s sarcomaOdontogenic keratocystRhabdomyosarcomaMelioidosisSolitary cystic ameloblastomaQuestion 2 What is the appropriate next step?Fine needle aspiration of cystExcision of lesionBone marrow aspirationMagnetic resonance imaging of thorax and abdomenStart intravenous ceftazidime Answers can be found on page XX