Bone and Joint Infections PPT by dr.bp.pptx

includes all bone and joint infection

1. Bone and Joint Infections DR.BHARTI PAWAR (PT)

2. OSTEOMYELITIS 1) Definition : Osteomyelitis is an infection of the bone. Osteomyelitis is classified as either acute or chronic

3. OSTEOMYELITIS 2) Pathophysiology The most common mode by which organisms reach the bone is by Hematogenous spread (i.e., either bacteremia or fungemia ) from a distant site. Mycobacterial and fungal osteomyelitis often arise from the initial site of infection in the lung. direct extension from an infected contiguous site such as a skin or soft tissue infection. It also can occur following trauma that results in an open fracture and direct contamination of the bone. Many sources are undetected.

4. OSTEOMYELITIS Site of bone infection In children, hematogenous spread tends to result in osteomyelitis located at the end of long bones (at the metaphyses ) that are richly endowed with blood vessels. In adults, hematogenous spread results most commonly in vertebral osteomyelitis and discitis, not osteomyelitis of the long bones.

5. OSTEOMYELITIS Chronic osteomyelitis tends to occur in the lower extremity, especially in diabetics who often have vascular insufficiency. They are predisposed to skin and soft tissue infections that extend into the bone

6. OSTEOMYELITIS 4) Clinical Manifestations a) The most characteristic clinical manifestations are bone pain and localized tenderness at the site of infection. b) Most patients also have constitutional symptoms such as fever, night sweats, and fatigue. c) Limited range of motion of an affected site is seen.

7. Difference between acute and chronic osteomyelitis acute osteomyelitis chronic osteomyelitis Onset of symptoms the symptoms occur abruptly and progress rapidly the course is more indolent Relapses Less frequent More frequent Necrosis of the bone, and a sequestrum formation (an avascular piece of infected bone) Less frequent More frequent remove sequestra , is important to minimize the risk of relapse

8. Fig1:Chronic osteomyelitis.. White arrow points to draining fistula at site of chronic osteomyelitis Fig2: White arrow points to necrotic bone caused by chronic osteomyelitis

9. OSTEOMYELITIS TABLE 1: Organisms Causing Osteomyelitis with Various Predisposing Factors . Viruses, protozoa, and helminths do not cause osteomyelitis Viruses, protozoa, and helminths do not cause osteomyelitis

10. OSTEOMYELITIS Diagnosis A) A microbiologic diagnosis of acute osteomyelitis is most consistently made by 1) Culture of a specimen of the bone lesion. 2) Blood cultures are positive in approximately half of cases. B) Radiologic diagnosis in acute osteomyelitis 1) Defect in the bone accompanied by periosteal elevation Early in the disease, X-rays and even computed tomography (CT) scans may be negative . Magnetic resonance imaging (MRI) scans are the most sensitive radiologic tests for diagnosis of osteomyelitis

11. Periosteal elevation (in acute osteomyelitis of the tibia.

12. OSTEOMYELITIS Treatment Empiric therapy for acute osteomyelitis should include drugs that are bactericidal, penetrate well into bone, and include coverage for S. aureus . Vancomycin, nafcillin , or cephalexin administered parenterally can be used. Vancomycin is often used until the culture results and the sensitivity of the organism are known.

13. OSTEOMYELITIS If methicillin-resistant S. aureus (MRSA) is the cause then either vancomycin, daptomycin , or linezolid can be used. If gram-negative rods are the cause, then either ceftriaxone, ceftazidime, or cefipime can be used. The duration of therapy ranges from 3 to 6 weeks or longer. Surgical debridement of chronic osteomyelitis lesions is often necessary.

14. Prevention 1) There is no vaccine effective against the common causes of osteomyelitis. 2) Chemoprophylaxis is typically not employed. Generally speaking, prophylactic antibiotics are not recommended prior to dental procedures to prevent prosthetic joint infection. 3)Proper foot care in diabetics can prevent osteomyelitis.

15. INFECTIOUS (SEPTIC) ARTHRITIS Definition Infectious (septic) arthritis is an infection of the joints. The terms infectious and septic are used to distinguish these infections from immune-mediated arthritis, such as rheumatoid arthritis.

16. Pathophysiology 1) Organisms typically reach the joint via the bloodstream 2) Less frequently, organisms enter the joints through penetrating trauma, medical procedures such as arthroscopy, or a contiguous osteomyelitis. Patients with long-standing rheumatoid arthritis and those with prosthetic hips and knees are predisposed to infectious arthritis.

17. Organisms Causing Infectious Arthritis

18. Organisms Causing Infectious Arthritis Bacteria, especially S. aureus , cause the vast majority of cases of infectious (septic) arthritis. Monoarticular involvement of a large weight-bearing joint, such as the hip or knee, is the most common presentation

19. Clinical Manifestations The acute onset of an inflamed joint, typically a large weight bearing joint such as the hip or knee, is the typical manifestation Fever is often present. On physical examination, the affected joint is red, warm, and swollen, and a joint effusion is typically present, limitation of joint movmenta joint, especially in a child, may be a sign of infectious arthritis

20. FIGURE 3:Septic arthritis of knee. Note swollen and inflamed left knee..

21. Diagnosis of infectious arthritis 1) Lab diagnosis Culture of a specimen of the joint fluid. Blood cultures are positive in less than 30% of cases. Synovial Fluid Analysis Analysis of synovial fluid aspirated from a swollen joint plays an important role in the diagnosis of arthritis.

22. Table1 : Synovial Fluid Findings in Arthritis

23. Diagnosis of infectious arthritis 2)Radiologic diagnosis infectious arthritis : Soft tissue swelling. Evidence of joint destruction can be seen if the infection progresses

24. Treatment Untreated infectious arthritis can lead to joint destruction and loss of mobility, so prompt antibiotic treatment is required for optimal recovery . 1) Empiric therapy for infectious arthritis should include drugs such as vancomycin, nafcillin , or cefazolin that are bactericidal against S. aureus . 2) Ceftriaxone should be used if there is evidence that N. gonorrhoeae is the cause. 3) Removal of joint fluid via arthrocentesis and/or surgical drainage is an important adjunct to antibiotics.

25. VIRAL (IMMUNE COMPLEX) ARTHRITIS Viral arthritis is often called immune complex arthritis because the virus does not infect the joint but rather, the virus forms immune complexes with antiviral antibody that is deposited in joints and elicits an inflammatory response.

26. VIRAL (IMMUNE COMPLEX) ARTHRITIS The clinical features of viral arthritis 1) Arthralgia (painful joints but without visible inflammation) 2) Or frank arthritis in which inflammation is apparent. 3) Most cases of viral arthritis are of short duration and resolve spontaneously, but chronic arthritis may occur. 4) The small joints of the hands are most often affected, but large joints can also be involved.

27. VIRAL (IMMUNE COMPLEX) ARTHRITIS Causative agents of viral arthritis viral arthritis occurs during the course of infection by several viruses. Rubella virus, Parvovirus B19(is an important cause in that the lesions resemble those of rheumatoid arthritis), hepatitis C virus also resemble rheumatoid arthritis, hepatitis B virus and dengue virus. There is no antiviral treatment for viral arthritis

28. REACTIVE ARTHRITIS Reactive arthritis: is the term used to describe arthritis that occurs following infection by several bacteria that infect the gastrointestinal or genitourinary tract. The bacteria do not infect the joints. Rather, the arthritis is a result of the immune response to the bacterial infection. People who are HLA-B27 positive are predisposed to reactive arthritis. The bacteria commonly associated with this arthritis are Campylobacter , Shigella , Salmonella , Yersinia , and Chlamydia

29. Clinical manifestation of reactive arthritis The main clinical manifestation is an asymmetric arthritis of the knee or ankle accompanied by fever. It typically resolves within a few days or weeks, but chronic arthritis may occur. Recurrences are common. Culture of synovial fluid is negative. Reactive arthritis accompanied by conjunctivitis and urethritis is called Reiter’s syndrome.

30. Treatment of reactive arthritis Nonsteroidal anti-inflammatory drugs are considered first-line therapy. Antibiotics have no effect on reactive arthritis .

31. RHEUMATIC FEVER Rheumatic fever is an immune-mediated, poststreptococcal disease that affects the joints, heart, brain, and skin. It follows pharyngitis caused by Streptococcus pyogenes (group A Streptococcus ). It typically occurs in children ages 5 to 15 years.

32. Clinical picture Rheumatic fever typically begins with a migratory polyarthritis involving the large joints approximately 2 to 3 weeks after the pharyngitis. Carditis often occurs and is the main, life-threatening component of rheumatic fever.

33. the diagnosis. Two major manifestations or one major plus two minor manifestations suggest the diagnosis (the Jones criteria) The diagnosis. Two major manifestations or one major plus two minor manifestations suggest the diagnosis. In addition, laboratory evidence of prior infection by S. pyogenes is needed. This consists of either (1) a positive throat culture or positive rapid streptococcal antigen test or (2) a rising anti– streptolysin O antibody titer

34. Treatment The drug of choice is aspirin to reduce the inflammation. Antibiotics such as penicillin G have no effect on the course of the disease but can be given to reduce carriage of streptococci in the pharynx.

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