| Download the amazing global Makindo app: Android | Apple | |
|---|---|
| MEDICAL DISCLAIMER: Educational use only. Not for diagnosis or management. See below for full disclaimer. |
Prevotella (Bacteroides) melaninogenica
Related Subjects: |Pasteurella Multocida |Capnocytophaga canimorsus |Snake Bites |Dog Bites |Tetanus
📖 About
- Prevotella melaninogenica (formerly Bacteroides melaninogenica) → Gram-negative, anaerobic bacterium.
- Part of the normal oral, GI, and genital flora but opportunistic in disease.
- Produces melanin → black-pigmented colonies on culture media.
🔬 Characteristics
- Gram-negative, strict anaerobe.
- Melanin production → diagnostic black pigmentation in vitro.
- Opportunistic pathogen → pathogenic if barriers disrupted.
🏠 Source
- Normal flora of oral cavity, GI tract, and genital tract.
- Becomes pathogenic in wounds (esp. human bites 👄), trauma, or aspiration events.
⚠️ Pathogenicity
- Human bite wound infections: Common due to its oral flora reservoir.
- Chest infections: Aspiration pneumonia, lung abscesses, empyema → esp. in poor dental hygiene or immunocompromised patients.
- Periodontal disease: Contributes to gum disease and oral abscesses.
- UTIs: Rare, usually linked to instrumentation or comorbidities.
🧬 Antibiotic Resistance
- Beta-lactamase production → resistance to many penicillins ❌.
- Macrolide (e.g. erythromycin) and clindamycin resistance reported in some strains.
💊 Management
- Antibiotics:
- Metronidazole → highly effective against anaerobes.
- Amoxicillin–clavulanate → overcomes beta-lactamase resistance.
- Carbapenems → reserved for severe or resistant cases.
- Surgery: Drainage or debridement if abscess or wound infection present.
⚠️ Exam pearl: Think Prevotella melaninogenica in human bite wound infections and aspiration pneumonia with black-pigmented anaerobes. Management = metronidazole ± surgical drainage.
| The content on this website is provided for educational and informational purposes only to support exam preparation (e.g., MLA, MRCP, USMLE) and learning. This is NOT medical advice, diagnosis, treatment, or professional guidance. It does not replace consultation with a qualified healthcare professional, official guidelines (e.g., NICE, GMC, BNF), or supervised clinical practice. Always verify information with current, authoritative sources. Makindo and its contributors accept no liability for any reliance on this content, including errors, omissions, or any resulting harm, loss, or consequences. By using this site, you agree to these terms. |
|
|
Categories
- A Level
- About
- Acute Medicine
- Anaesthetics and Critical Care
- Anatomy
- Anatomy and Physiology
- Biochemistry
- Book
- Cardiology
- Collections
- CompSci
- Crib Sheets
- Dental
- Dermatology
- Differentials
- Drugs
- ENT
- Education
- Electrocardiogram
- Embryology
- Emergency Medicine
- Endocrinology
- Ethics
- Foundation Doctors
- GCSE
- Gastroenterology
- General Practice
- Genetics
- Geriatric Medicine
- Guidelines
- Gynaecology
- Haematology
- Hepatology
- Immunology
- Infectious Diseases
- Infographic
- Investigations
- Lists
- Mandatory Training
- Medical Students
- Microbiology
- Nephrology
- Neu
- Neurology
- Neurosurgery
- Nutrition
- OSCE
- OSCEs
- Obstetrics
- Obstetrics Gynaecology
- Oncology
- Ophthalmology
- Oral Medicine and Dentistry
- Orthopaedics
- Paediatrics
- Palliative
- Pathology
- Pharmacology
- Physiology
- Procedures
- Psychiatry
- Public Health
- Radiology
- Renal
- Respiratory
- Resuscitation
- Revision
- Rheumatology
- Statistics and Research
- Stroke
- Surgery
- Toxicology
- Trauma and Orthopaedics
- USMLE
- Urology
- Vascular Surgery