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Published on: June 4, 2012
Purulent pericarditis caused by methicillin-sensitive Staphylococcus aureus bacteriuria
Lorraine Mascarenhas1, Dzhalal Agakishiev2, Morgan Freeman3
1Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, USA. masca014@umn.edu.
Background:
Purulent pericarditis (PP)- a purulent infection involving the pericardial space-requires a high index of suspicion for diagnosis as it often lacks characteristic signs of pericarditis and carries a mortality rate as high as 40% even with treatment. Common risk factors include immunosuppression, diabetes mellitus, thoracic surgery, malignancy, and uremia. Most reported cases of PP occur in individuals with predisposing risk factors, such as immunosuppression, and result from more commonly observed preceding infections, such as pneumonia, osteomyelitis, and meningitis. We report a case of PP due to asymptomatic bacteriuria in a previously immunocompetent individual on a short course of high-dose steroids.
Case Presentation:
An 81-year-old male presented for severe epigastric pain that worsened with inspiration. He had been on high-dose prednisone for presumed inflammatory hip pain. History was notable for urinary retention requiring intermittent self-catheterization and asymptomatic bacteriuria and urinary tract infections due to methicillin-sensitive Staphylococcus aureus (MSSA). During the index admission he was found to have a moderate pericardial effusion. Pericardial fluid cultures grew MSSA that had an identical antibiogram to that of the urine cultures. A diagnosis of purulent pericarditis was made.
Conclusion:
PP requires a high index of suspicion, especially in hosts with atypical risk factors. This is the second case of PP occurring as a result of asymptomatic MSSA bacteriuria. Through reporting this case we hope to highlight the importance of early recognition of PP and the clinical implications of asymptomatic MSSA bacteriuria in the setting of urinary instrumentation and steroid use.
Insights
Purulent pericarditis (PP) can arise from asymptomatic bacteriuria, even in immunocompetent patients using steroids. Early recognition is crucial for this serious infection, often presenting with atypical symptoms.
Area of Science:
- Infectious Diseases
- Cardiology
- Nephrology
Background:
- Purulent pericarditis (PP) is a serious pericardial infection with high mortality.
- Typical risk factors include immunosuppression, diabetes, and malignancy.
- PP often lacks classic signs, necessitating a high index of suspicion.
Observation:
- An 81-year-old male on high-dose steroids presented with epigastric pain.
- He had a history of urinary retention and asymptomatic bacteriuria (MSSA).
- A pericardial effusion was identified, with fluid cultures positive for MSSA.
Findings:
- The pericardial fluid MSSA strain matched the urine isolate.
- A diagnosis of purulent pericarditis secondary to asymptomatic bacteriuria was made.
- This case highlights an atypical presentation of PP in an immunocompetent patient.
Implications:
- Emphasizes the importance of considering PP in patients with atypical risk factors.
- Suggests asymptomatic bacteriuria, especially with urinary instrumentation and steroid use, can lead to PP.
- Underscores the need for early diagnosis and management of PP.
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