Unraveling Complexity: Mycoplasma Pneumonia Complicated by Hemolytic Anemia, Renal Failure, and Venous Thromboembolism; A Case Report

Introduction: Mycoplasma pneumoniae, a common respiratory pathogen, is a leading cause of atypical pneumonia, often presenting with a nonproductive cough, fever, and malaise. While typically causing mild upper respiratory symptoms, M. pneumoniae can lead to severe complications, including hemolytic anemia, acute renal failure, and venous thromboembolism. These complications are relatively uncommon but highlight the pathogen's capacity to affect multiple organ systems. Here, we present a rare and complex case of M. pneumoniae infection complicated by hemolytic anemia, renal failure, and venous thromboembolism in an adult patient. Case Presentation: A 58-year-old man with no prior comorbidities presented to the emergency department (ED) with complaints of fever for 12 days, cough, shortness of breath, and generalized fatigue for 10 days. On examination, he was icteric and exhibited coarse breath sounds, and his urine was dark in colour. Despite an initial treatment regimen consisting of ceftriaxone, doxycycline, and methylprednisolone, the patient's condition deteriorated. Investigations revealed pneumonia, hemolytic anemia, and acute renal failure. A respiratory panel identified mycoplasma pneumoniae leading to a diagnosis of complicated mycoplasma pneumonia; his antibiotic regimen was subsequently to azithromycin. The patient was discharged after a week but returned the same day with symptoms indicative of venous thromboembolism. Further evaluation revealed bilateral venous thrombosis and bilateral acute pulmonary embolism, necessitating heparin anticoagulation and a subsequent transition to oral apixaban therapy. The patient was stabilized and discharged, with no complications noted at follow-up. Discussion This case underscores the rare but potentially severe extrapulmonary manifestations of M. pneumoniae infection. Hemolytic anemia associated with this pathogen is believed to be due to cold agglutinin antibodies targeting erythrocyte antigens, while renal failure may result from acute tubular injury secondary to hemolysis. Venous thromboembolism, although rare, is increasingly recognized as a complication of M. pneumoniae, particularly in cases where vascular endothelium is directly affected or systemic hypercoagulability is induced. Conclusion This case illustrates the complexity of diagnosing and managing severe complications of M. pneumoniae infection, including hemolytic anemia, renal failure, and venous thromboembolism. Early recognition and appropriate management of these complications are crucial to improving patient outcomes and avoiding fatal sequelae.