Title : Iatrogenic hypercalcaemia secondary to antibiotic-eluting absorbable Calcium Sulphate Beads (CSB) in orthopaedic surgery
Abstract:
Introduction: Calcium-Sulphate Beads (CSB) are bio-absorbable antibiotic carriers which are used to manage surgical site infections as well as fill dead space. Iatrogenic hypercalcaemia from using CSB is a rare but potentially serious adverse effect. The incidence of hypercalcaemia due to CSB is about 4.2%, with about 3.91% of cases being transient in nature, and 0.28% requiring treatment(1).
Method: In this case report, we describe a patient who developed symptomatic hypercalcaemia secondary to using CSB during a Girdlestone operation.
Results: An 86-year-old female presenting with decreased consciousness (altered mental status) two days after undergoing a Girdlestone procedure (femoral head ostectomy) for the infected right hemiarthroplasty. The dead space had been filled using antibiotic-eluting CSB . She was afebrile with normal cardiovascular respiratory and abdominal examinations but a P on the AVPU scale (response only to painful stimuli). She had no past medical history of parathyroid or calcium disorders but had a recent medical history of stage 1 acute kidney injury on her day one postop bloods tests. She was on calcium and vitamin D supplementation alongside bisphosphonate therapy (Alendronic acid), which had been initiated 2 years prior. Laboratory findings taken on symptom onset revealed marked hypercalcaemia. Management was initiated with aggressive fluids and one dose of IV Zoledronic acid. Following treatment with fluid therapy and bisphosphonates, her clinical condition improved. Her calcium levels returned to normal range within 7 days of treatment initiation.
Conclusion: This case illustrates the importance of including iatrogenic hypercalcaemia as a differential diagnosis for post-operative patients presenting with altered mental status after the use of CSB(2).
