Title

Beyond the Lungs: A Case of Legionella-Induced Rhabdomyolysis and AKI


Authors

Byczynski, Aaron DO1, Green, Alex MD1, Szczygielski, Julie MS42, Garcia, Jasmine MS42, Fathima, Aquila MD1

1. Division of General Internal Medicine, Medical College of Wisconsin, 8701 W. Watertown Plank Rd, Milwaukee, WI 53226, USA

2. Medical College of Wisconsin, 8701 W. Watertown Plank Rd, Milwaukee, WI 53226, USA


Introduction

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide. (1) Its clinical presentation is variable, including fever, productive cough, respiratory failure, and sepsis. Legionella species are an uncommon cause of atypical pneumonia that can present with severe extra-respiratory complications. (1,2,3,4) We present a case of rhabdomyolysis-associated acute tubular necrosis (ATN) due to CAP from legionella pneumophila.


Case Presentation

This is the case of a 39-year-old woman who initially presented to the emergency department with nausea, vomiting, diarrhea, exertional dyspnea, and a productive cough. She also described subjective fever, chills, and myalgias. Initial vital signs were only significant for hypotension. The physical exam was only remarkable for diffuse respiratory crackles. Initial labs were significant for sodium 130 mmol/L, serum creatinine (sCr) 1.04 mg/dL, and lactic acid 2.5 mmol/L. Notably, there was no leukocytosis. Chest radiograph showed no acute consolidations. Initial treatment was 500 mg azithromycin, 1 g ceftriaxone, and adequate volume resuscitation before admission to the general medicine floor for management of distributive shock due to sepsis from a presumed respiratory source. A thorough infectious workup was completed and only resulted in legionella urine antigen positivity for legionella pneumophilia serogroup 1. Treatment for pneumonia was switched to Moxifloxacin for 5 days and she clinically improved. Before positive legionella testing, she developed acute kidney injury (AKI) with a serum creatine elevation from 1.0 to 4.5 mg/dL in 24 hours. Workup for AKI included renal ultrasound, urine electrolytes, and creatinine kinase (CK) due to suspected ATN. She also became anuric despite a diuretic challenge with Bumex and Metolazone. Workup revealed CK elevation to 226,572 U/L and peaked at 257,763 U/L. The sCr peaked at 8.30 mg/dL. Due to worsening AKI and anuria for 48 hours, she was transferred to the Intensive Care Unit for continuous renal replacement therapy (CRRT). After 48 hours of CRRT, she was transferred back to the medicine floor. Due to continued oliguria, she required outpatient hemodialysis upon discharge. After 4 weeks of dialysis, she returned to her pre-hospitalization state of health.


Discussion

Legionella pneumonia, a severe form of pneumonia, can lead to significant complications beyond respiratory symptoms. Rhabdomyolysis, a potentially life-threatening condition characterized by muscle breakdown, has been identified as a mechanism of AKI in patients with Legionella pneumonia. (1,2,3,4) The exact pathophysiology remains unclear, but several factors may contribute. These proposed mechanisms include direct toxic effects of Legionella on muscle cells, endothelial injury leading to reduced muscle blood flow, and immune-mediated muscle damage, which leads to muscle breakdown, elevation of creatine kinase, and potentially renal failure. (1) In this case, the patient developed pigment nephropathy, a rhabdomyolysis complication characterized by myoglobin deposition in the renal tubules. Early recognition of elevated creatine kinase levels and prompt initiation of supportive care, including aggressive hydration and renal replacement therapy, are crucial in managing rhabdomyolysis and preventing severe AKI. (1) This case highlights the importance of considering extrapulmonary manifestations, such as rhabdomyolysis and AKI, in patients with Legionella pneumonia as early intervention can significantly improve patient outcomes.


References

  1. Soni, A. J., & Peter, A. (2019). Established association of legionella with rhabdomyolysis and renal failure: A review of the literature. Respir Med Case Rep, 28.
  2. Brivet, F., Pham, T., Petitpretz, P., & Delfraissy, J. F. (1984). Rhabdomyolysis, acute renal failure and Legionnaires’ disease. Chest, 86. https://doi.org/10.1378/chest.86.6.943-a
  3. Giannoglou, G. D., Chatzizisis, Y. S., & Misirli, G. (2007). The syndrome of rhabdomyolysis: pathophysiology and diagnosis. Eur J Intern Med, 18. https://doi.org/10.1016/j.ejim.2006.09.020
  4. Rodriguez, E. E., Woods, K. L., Deno, R. E., Wallin, J. D., & O’Neill, W. M. (1983). Rhabdomyolysis-induced acute renal failure in Legionnaires’ disease. South Med J, 76. https://doi.org/10.1097/00007611-198310000-00041