Anesthetic Management of an Elective Cesarean Section in a Patient With Systemic Mastocytosis and Latex Allergy, Complicated by Incidental Intraoperative Wolff-Parkinson-White Pre-excitation: A Case Report.

Systemic mastocytosis (SM) is a rare clonal mast cell disorder in which physical, pharmacological, or emotional triggers can provoke massive mediator release and life-threatening anaphylactoid reactions. Pregnancy and delivery are recognized as high-risk periods that demand careful multidisciplinary planning. Cardiovascular manifestations of mast cell activation disease are increasingly recognized; however, their interplay with primary conduction abnormalities is poorly characterized, and the available evidence is largely limited to isolated case reports. We describe the elective cesarean delivery of a 40-year-old woman with indolent SM and documented latex allergy, managed within a multidisciplinary framework. After corticosteroid and antihistamine premedication in a latex-free operating room, spinal anesthesia was performed without intrathecal opioids; spinal-induced hypotension was treated with phenylephrine boluses, and postoperative analgesia relied on paracetamol alone, with nonsteroidal anti-inflammatory drugs (NSAIDs) deliberately avoided. Serial serum tryptase concentrations remained within the normal range throughout the perioperative period (baseline 7.9 µg/L; intraoperative 10.1 µg/L; early postoperative 9.3 µg/L), with no value reaching the consensus threshold for significant mast cell activation, supporting the effectiveness and safety of the adopted strategy. Unexpectedly, a new Wolff-Parkinson-White (WPW) pre-excitation pattern appeared intraoperatively in a patient with a normal antepartum tracing. She remained asymptomatic, and the subsequent cardiac workup was unremarkable, with outpatient electrophysiological follow-up arranged. This case highlights the value of a structured, prevention-oriented anesthetic strategy in SM, supports spinal anesthesia with hyperbaric bupivacaine as a reasonable preferred option when not contraindicated, and broadens the spectrum of perioperative electrocardiographic findings that may be observed in this population.