Related Experiment Videos

Septic arthritis in a native joint due to Anaerococcus prevotii

S Jain1, V Bui, C Spencer

  • 1Department of Microbiology, Mid Staffordshire General Hospital, Weston Road, Stafford, UK. sangita.jain@msgh-tr.wmids.nhs.uk

Journal of Clinical Pathology
|March 18, 2008
PubMed

Insights

Anaerococcus prevotii, a rare anaerobic streptococcus, caused septic arthritis in an injecting drug user. Prompt identification and metronidazole treatment led to patient recovery, highlighting the importance of considering rare pathogens.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Rheumatology

Background:

  • Septic arthritis is a serious joint infection often caused by Staphylococcus aureus.
  • Injecting drug use is a significant risk factor for developing septic arthritis.
  • Standard antibiotic treatments may not be effective against less common pathogens.

Observation:

  • A 37-year-old male injecting drug user presented with symptoms of septic arthritis.
  • Initial blood cultures grew Staphylococcus aureus, but treatment with flucloxacillin and fusidic acid was ineffective.
  • Knee aspirate culture, after a prolonged incubation period, identified Anaerococcus prevotii.

Findings:

  • Anaerococcus prevotii was the causative agent of septic arthritis in this case.
  • A large thigh abscess containing Anaerococcus prevotii was drained.
  • The patient's condition improved significantly after the addition of metronidazole to the treatment regimen.

Implications:

  • This case underscores the importance of considering rare anaerobic bacteria, such as Anaerococcus prevotii, in the differential diagnosis of septic arthritis, especially in high-risk individuals.
  • Extended incubation times for cultures may be necessary for identifying fastidious organisms.
  • Successful treatment involved a combination of surgical drainage, appropriate antibiotics (including metronidazole), and addressing the underlying risk factor (drug use).

Related Concept Videos

Endocarditis I: Introduction01:25

Endocarditis I: Introduction

Introduction:Endocarditis is the infection of the endocardium, the inner lining of the heart and its valves. When the heart muscle is involved, the condition is termed myocarditis, while an infection of the outer lining is called pericarditis. Infective endocarditis (IE) primarily affects the endocardium, where pathogens adhere to the valves or lining, forming vegetation that can lead to severe complications. Infective endocarditis occurs when microorganisms, usually bacteria from other body...
Bacterial Meningitis01:24

Bacterial Meningitis

Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
Bacterial Meningitis I: Introduction01:22

Bacterial Meningitis I: Introduction

Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
Staphylococcal Skin Infections01:29

Staphylococcal Skin Infections

Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
Streptococcal Pharyngitis01:27

Streptococcal Pharyngitis

Streptococcal pharyngitis, commonly known as “strep throat,” is an acute infection of the oropharyngeal tissues caused by the Gram‑positive Group A Streptococcus (Streptococcus pyogenes). Transmission occurs primarily through respiratory droplets expelled during coughing, sneezing, or talking.Mechanisms of Host Entry and Immune EvasionUpon entering the host, S. pyogenes adheres to the mucosal epithelial cells of the pharynx via surface proteins, notably lipoteichoic acid and the antiphagocytic...
Bacterial Meningitis II: Pathophysiology01:26

Bacterial Meningitis II: Pathophysiology

Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...