This document discusses septic arthritis, which is a joint infection caused by bacteria, viruses, or other microorganisms invading the joint space. Common causes include bloodstream dissemination from a distant infection, adjacent soft tissue infection, or trauma. Symptoms include intense joint pain, swelling, and inability to move the joint. Diagnosis involves joint fluid analysis showing inflammatory cells. Treatment requires appropriate antibiotics based on culture results as well as surgical drainage of the joint in some cases. Risk factors include diabetes, rheumatoid arthritis, or immunosuppression. Prompt diagnosis and treatment are important to prevent joint destruction and systemic infection.

2. Septic Arthritis
 Septic arthritis, also known as infectious arthritis,
represents a direct invasion of joint space by various
microorganisms, most commonly caused by a variety
of bacteria, viruses, mycobacteria and fungi

4.  Dissemination of pathogens via the blood, from distant site….
(Most common)
 Dissemination from an acute osteomylitic focus
 Dissemination from adjacent soft tissue infection,
 Entry via penetrating trauma
 Entry via iatrogenic means

6. On entering the joint space, the bacteria initially deposit
in the synovial membrane and produce an inflammatory
reaction.
Synovial membrane hyperplasia develops in 5 to 7 days,
and the release of cytokines leads to hydrolysis of
proteoglycans and collagen, cartilage destruction, and
eventually bone loss.
Direct pressure necrosis due to large synovial effusion
results in further cartilage damage

7. Non Gonococcal
Bacterial Arthritis

8.  Usually related with underlying abnormality
 Bacteremia (IVDA, Endocarditis, Infections at other sites )
 Damaged or prosthetic joints
 Compromised immunity (DM, CKD, Alcoholism, Cirrhosis,
Immunosuppressive Rx )
 Loss of skin integrity

9.  Staphylococcus Aureus—50%
 Streptococcal species, such as Streptococcus viridans,
S Pneumoniae & group B streptococci
 Gram-negative bacilli -- 10% --
E.coli & Psudomonas -More common

10. Sites:
Monoarticular involvement -- 85 %
Knee– Most common
Other
Hip, Wrist, Shoulder & Ankle
Sternoclavicular and Sacroiliac joint – IVDA

11. Symptoms and Signs :
Acute Onset
• Intense joint pain .
• Joint swelling .
• Joint redness .
• Unable to move the limb with the infected joint .
• Low-grade fever.
• Chills

12.  Investigations :
 Non specific features of acute inflammation-
leucocytosis, ESR,CRP-are suggestive but not
diagnostic
 Joint fluid analysis
(Cell Type, Count, Gram stain, Culture +ve in 70-90 %)
 Blood Culture--- 50% Positive

14. Imaging –
Xray, CT, MRI --------less helpful in diagnosis
Can demonstrate
• Joint effusion
• Synovial thickening
• Perisynovial edema
• Cartilage destruction
• Bone destruction
• Bursitis, tenosynovitis

15. Treatment:
 General Measures:
The first priority is to aspirate the joint and examine the
fluid, treatment is then started without further delay.
• Analgesics and splinting of the involved joint in the
position of maximal comfort to alleviate pain.
• Fluid replacement and nutritional support may be
required.
• Other foci of infection and any coexisting medical
conditions must be identified and treated appropriately

16. Treatment:
Appropriate Antibiotics & Drainage of affected joint
Empiric Abx:
Oxacillin + 3rd Gen Cephalosporin
Replace Oxacillin with Vancomycin if MRSA suspected
Alter Abx based on culture results
Duration of Rx: 6 weeks

17. Drainage of Joint :
Consider Ortho Consult
Arthroscopic Lavage , Debridement & Drain placement
Open surgical Drainage

18. Drainage:
Indication of Surgical Drainage:
1-Joints that do not respond to antimicrobial therapy and
daily arthrocentesis
2-. Any joint with limited accessibility, including the
sternoclavicular or the hip joint
3-Patients with underlying disease, including diabetes,
rheumatoid arthritis, immunosuppression, or other systemic
symptoms, should be treated more aggressively with earlier
surgical intervention

19. Factor include
•Health of Patient
•Organism
•How quickly Rx is started
Mortality rate – 30% in Polyarticular type of Septic
arthritis

20. Gonococcal
Arthritis

21.  Usually in otherwise healthy individuals
 Sexually active
 More common in Women than Men
 Congenital Complement component deficiency

22.  Migratory Polyarthralgias– Wrist, Knee, Ankle or Elbow
 Tenosynovitis –Wrist, fingers, Ankles, or toes (60%)
Tenosynovitis is inflammation of the synovium (protective sheath that covers tendons)
 Purulent Monarthritis –Knee, Wrist, Ankle , Elbow –(40%)
 Charcteristic skin lesion – 2 to 10 small nacrotic pustules on palms and
soles
 Fever

24.  Investigations :
 Non specific features of acute inflammation-
leucocytosis, ESR,CRP-are suggestive but not
diagnostic
 Joint fluid analysis
Cell Type Count, Gram stain, Culture +ve in <50%)
 Blood Culture--- 40% Positive
 Urethral, Throat & Rectal cultures

25. Imaging –
X-ray, CT, MRI less helpful in diagnosis—Normal
Can demonstrate joint effusion Soft tissue swelling

26. Hospitalization
Empiric Abx – 3rd Gen Cephalosporin

27. More favorable prognosis as compared to
Non Gonococcal Septic Arthritis
Dramatic response to Abx in 24 to 48 Hr

28. Gout--
Pseudogout--
Lyme Arthritis--
Haemarthrosis--
Bursitis--
Reactive arthritis--
Rheumatic Fever– Migratory polyarthritis

29.  Acute monoarthritis should be evaluated emergently to
rule out the possibility of septic arthritis.
 Untreated septic arthritis can lead to rapid joint space
destruction and systemic sepsis, so early diagnosis is
imperative.
 Consider septic arthritis in patients with underlying
inflammatory arthritis if one joint is more acutely inflamed
than others.

30.  Aspiration of the involved joint is critical to identifying the
organism.
 Therapy with empirical antibiotics should immediately
follow aspiration, with subsequent narrower coverage only
after culture results are obtained.
 Risk factors including old age, trauma, limb ulceration,
and prior hospitalization can predict the likely organism
infecting the joint.

31.  Patients receiving immunosuppressive medications,
steroids, and chemotherapy are at greater risk for
developing septic arthritis.
 Treatment includes appropriate joint drainage and
surgical options depending on the joint involved.

32.  Case:
 A 55-year-old man is hospitalized for a 2-day history of left knee pain. He has a history
of type 2 diabetes mellitus and hyperlipidemia. Medications are glipizide, simvastatin,
and low-dose aspirin.
 On physical examination, temperature is 38.3 ° C (100.9 ° F), pulse rate is 98/min,
respiration rate is 18/min, and blood pressure is 145/92 mm Hg. The left knee is
erythematous, warm, swollen, and tender to touch. The patient resists movement of the
left knee. The remainder of the musculoskeletal examination is unremarkable.
 The leukocyte count is 12,000/μL (12 × 109/L). The hemoglobin level, serum metabolic
panel, uric acid level, and urinalysis are normal.
 Arthrocentesis of the left knee joint yields cloudy yellow synovial fluid with a leukocyte
count of 105,000/μL (105 × 109/L) (97% polymorphonuclear cells). Gram's stain of the
fluid reveals gram-positive cocci in chains. Polarized light microscopy shows no
crystals.
 In addition to daily aspiration of the knee, which of the following is the
most appropriate next step in this patient's treatment?
 A Naproxen
 B Intravenous imipenem
 C Oral dicloxacillin
 D Intravenous ceftriaxone
 E Intra-articular cefazolin

33.  Correct Answer: D ------- Intravenous ceftriaxone
 Gram-positive cocci in chains

34. Questions ?

35. Thank you

36. Thank you