Salmonella-Induced Immunothrombosis: An Unusual Case of Pulmonary Embolism in the Setting of Enteric Infection.

Diabetic ketoacidosis (DKA) is a well-recognized metabolic emergency, often precipitated by infection or stress. Non-typhoidal Salmonella (NTS) gastroenteritis is usually self-limiting but can assume clinical significance in metabolically compromised patients, occasionally precipitating thrombotic complications. We describe a unique case where gastroenteritis in the setting of DKA was associated with pulmonary embolism (PE) in an ambulant patient. A 46-year-old previously healthy woman presented after a minor fall complicated by a seizure. Imaging revealed an incidental calcified right-frontal meningioma. Baseline investigations demonstrated new-onset diabetes with DKA and severe iron-deficiency anaemia, managed with insulin, fluids, and oral iron. On day seven, she collapsed with hypotension, tachycardia, and hypoxia. A Wells score of 6, right-ventricular dilation on bedside echocardiography, and markedly elevated D-dimer raised suspicion for PE, confirmed on CT pulmonary angiography. Anticoagulation with apixaban was commenced. Within 24 hours, she developed acute diarrhoea; stool cultures isolated NTS serogroup B. She received targeted ciprofloxacin with full clinical recovery. This case illustrates that acute Salmonella gastroenteritis in the metabolically stressed state of DKA can precipitate immunothrombosis and PE, even without systemic sepsis. It underscores the importance of timely recognition of PE in unexplained collapse and the need for integrated multidisciplinary management across neurological, endocrine, haematological, and infectious domains.