Aim and background: Achromobacter xylosoxidans is a rare opportunistic pathogen that can cause severe infections, particularly in immunocompromised patients. This case report describes a patient with A. xylosoxidans septicemia complicated by severe symptomatic bradycardia, hyperkalemia, and acute kidney injury (AKI) requiring dialysis. Case description: A 78-year-old female, a known case of hypertension, diabetes, and ischemic heart disease, presented with altered mental status and hypotension. She was found to have A. xylosoxidans septicemia, severe hyperkalemia, and symptomatic bradycardia requiring temporary pacing. Despite antibiotic treatment and management of electrolyte imbalances, the patient developed AKI requiring hemodialysis. Coronary angiography revealed critical triple-vessel disease, and the patient underwent successful coronary artery bypass grafting (CABG) surgery. Conclusion: This case highlights the potentially severe complications associated with A. xylosoxidans infections, including cardiac and renal dysfunction. Prompt recognition and aggressive management of these complications are crucial for patient survival. Clinical significance: This case emphasizes the importance of considering A. xylosoxidans as a potential cause of severe sepsis, especially in immunocompromised patients. Early diagnosis and appropriate antimicrobial therapy, along with management of associated complications such as cardiac and renal dysfunction, are essential for improving patient outcomes.