What is phlegmon (inflammation of soft tissue)?

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From the Guidelines

Phlegmon should be treated with broad-spectrum antibiotics, such as amoxicillin-clavulanate or clindamycin, for 7-14 days, and supportive measures including rest, elevation, and pain management, as it represents a diffuse inflammatory process that can progress to abscesses or systemic infection if left untreated. A phlegmon is an inflammatory mass or swelling in soft tissue, characterized by diffuse inflammation without a well-defined border or collection of pus, and it typically occurs as a result of bacterial infection spreading through tissue planes 1. The management of skin and soft-tissue infections, including phlegmon, involves classifying the infection based on its necrotizing or non-necrotizing character, anatomical extension, and clinical condition of the patient 1.

Classification and Treatment

The classification of skin and soft-tissue infections can be done using various systems, including the 2018 WSES/SIS-E consensus conference recommendations, which suggest assessing the necrotizing or non-necrotizing character of the infection, the anatomical extension, and the clinical condition of the patient 1. The treatment of phlegmon generally involves antibiotics targeting the likely causative organisms, often broad-spectrum coverage for both aerobic and anaerobic bacteria. Common antibiotic choices include:

  • Amoxicillin-clavulanate (875/125 mg twice daily)
  • Clindamycin (300-450 mg four times daily)
  • A combination of a cephalosporin with metronidazole for 7-14 days depending on clinical response

Supportive Measures

Supportive measures for phlegmon include:

  • Rest
  • Elevation of the affected area if possible
  • Warm compresses
  • Pain management with acetaminophen or NSAIDs Unlike abscesses, phlegmons typically don't require surgical drainage unless they evolve into an abscess or fail to respond to antibiotics 1. Prompt treatment is important as phlegmons can progress to form abscesses, cause tissue necrosis, or lead to systemic infection if left untreated. The Infectious Diseases Society of America (IDSA) updated practice guidelines for the diagnosis and management of skin and soft-tissue infections in 2014, which divided infections by purulent and non-purulent, severity (mild, moderate, and severe), and tissue necrosis (necrotizing versus non-necrotizing) 1.

From the Research

Definition and Diagnosis of Phlegmon

  • Phlegmon is a rare disease associated with high risk of mortality, often deriving from different structures of the head and neck area, and can be odontogenic 2.
  • Imaging studies, especially computerized tomography, play a crucial role in the diagnosis of phlegmons 2.
  • Laboratory results and imaging results are essential in analyzing the course of the disease 2.

Treatment of Phlegmon

  • The treatment of phlegmon is based on surgical incision and drainage, as well as analgesia 2.
  • Antibiotics, such as streptococci and staphylococci, are effective in treating phlegmons 2.
  • Two types of surgical procedures can be performed: common abscess incision or broad incision along the sternocleidomastoid muscle 2.

Comparison with Other Conditions

  • Phlegmon can be compared to other conditions such as liver abscess, where empirical antimicrobial therapy with or without percutaneous aspiration or drainage is therapeutic 3.
  • The treatment of complicated appendicitis associated with abscess or phlegmon can vary from immediate appendectomy versus non-operative management with antibiotics and possible interval appendectomy 4.
  • Acute diverticulitis can be managed with antibiotics, intravenous fluid resuscitation, and intravenous antibiotics, and in some cases, surgical intervention may be required 5.

Antibiotic Treatment

  • Ciprofloxacin is a broad-spectrum antibacterial drug that can be effective in treating various infections, including those caused by Gram-negative and Gram-positive bacteria 6.
  • Ciprofloxacin can be used as an empirical oral antimicrobial regimen for the treatment of uncomplicated liver abscess, along with prompt percutaneous drainage or aspiration 3.

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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