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A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection
Published on: February 20, 2020
The Shadows of Normal Flora on Minor Wounds: A Case Report of an Uncommon Pathogen With Potentially Lethal
Khurram Arshad1, Farman Ali2, Yazan Alamro3
1Internal Medicine, Corewell Health East Dearborn, Dearborn, USA.
Abstract:
Staphylococcus lugdunensis is a gram-positive, coagulase-negative organism, typically found in the normal skin flora, predominantly colonizing the perineal region. It has gained recognition as an opportunistic pathogen capable of causing severe infections. This manuscript presents a case study of a 75-year-old female with multiple comorbidities, including hypertension, hyperlipidemia, atrial fibrillation on Xarelto, type 2 diabetes mellitus, hypothyroidism, and a bioprosthetic aortic valve. The patient exhibited symptoms of fever, chills, and lethargy following a dog scratch that resulted in wounds on the left lower extremity. Despite initial negative findings in the drug screen and unremarkable workup for other infectious etiologies, the patient's clinical course revealed the presence of S. lugdunensis in the blood cultures. Timely intervention with broad-spectrum intravenous antibiotics and a six-week course of cefazolin led to significant improvement without recurrence. Staphylococcus lugdunensis, previously considered a relatively benign microorganism, has become a significant player in infectious diseases, particularly causing skin and soft tissue infections and infective endocarditis (IE). It is considered an aggressive pathogen, especially in chronic immunocompromised personnel, with a high potential for morbidity and mortality. S. lugdunensis was found to be the fourth most common cause of IE. The manuscript discusses the epidemiology, clinical presentation, and management of S. lugdunensis infections, emphasizing the importance of early recognition and treatment to prevent potentially fatal outcomes.
Insights
Staphylococcus lugdunensis, a skin bacterium, can cause severe infections. Early antibiotic treatment is crucial for recovery, as shown in a case of a patient with multiple health issues.
Area of Science:
- Microbiology
- Infectious Diseases
- Clinical Medicine
Background:
- Staphylococcus lugdunensis, a coagulase-negative Staphylococcus species, is part of normal skin flora.
- It is increasingly recognized as an opportunistic pathogen causing severe infections, including infective endocarditis.
Observation:
- A 75-year-old female with multiple comorbidities presented with fever, chills, and lethargy after a dog scratch.
- Blood cultures revealed Staphylococcus lugdunensis despite initial negative workup for other infections.
Findings:
- The patient received broad-spectrum intravenous antibiotics followed by a six-week course of cefazolin.
- Significant clinical improvement was observed without recurrence of infection.
Implications:
- Staphylococcus lugdunensis infections require prompt diagnosis and management.
- Early recognition and treatment are vital to prevent severe morbidity and mortality associated with S. lugdunensis, especially in immunocompromised individuals.
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