Infections of the Bone

Question 1

Give 3 RFs for Septic Arthriti.

Answer 1

• Pre-existing joint disease – RA/OA
• Prosthetic joint
• IVDU
• Immunosuppressed
• Diabetes mellitus
• PMHx of IA corticosteroid injections/surgery

Question 2

A 37 year old man presents with joint pain. The pain is localised in his knee which is severe, 8/10, began suddenly two days ago and is relieved by analgesia. He has had a fever and a headache.

He takes no drugs, has NKDA, PMHx of diabetes and steroid injections for his OA.

He works as a labourer and smokes 30 a day, with a pack years of 40. He drinks 18 units of alcohol per week.

Give your likely DDx

Answer 2

Septic Arthritis

Question 3

37 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus.

His arthrocentesis shows a pathogen present; FBC shows leukocytosis and CRP elevated.

Give your DDx and Management.

Answer 3

Septic Arthritis

• ABX: Ceftriaxone (Meningococcal)/ Ceftriaxone + Azithromycin (Gonococcal)/ ∑ Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (TB)
-> Pathogen-guided (Empirical)
±
• Surgery: Joint aspiration
±
• Analgesia: Paracetamol/ Ibuprofen/ Diclofenac

Question 4

37 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus.

His arthrocentesis shows a pathogen present - gram negative diplococci; FBC shows leukocytosis and CRP elevated.

Give your likely DDx and the management

Answer 4

• ABX: Ceftriaxone (Meningococcal)/ Ceftriaxone + Azithromycin (Gonococcal)/ ∑ Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (TB)
-> Pathogen-guided (Empirical)
±
• Surgery: Joint aspiration
±
• Analgesia: Paracetamol/ Ibuprofen/ Diclofenac

Question 5

37 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus.

His arthrocentesis shows a pathogen present - gram positive cocci in irregular clusters; FBC shows leukocytosis and CRP elevated.

Give your likely DDx and the management

Answer 5

Septic Arthritis

Vancomycin

Question 6

37 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus and Tuberculosis. He has recently travelled to Egypt and came back with a recent cough too.

His arthrocentesis shows a pathogen present - rod-shaped bacteria which is weakly gram positive; FBC shows leukocytosis and CRP elevated.

Give your DDx and Tx

Answer 6

Septic arthritis

RIPPE

Question 7

37 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus. He has recently had 4 sexual partners.

His arthrocentesis shows a pathogen present - gram negative diplococci; FBC shows leukocytosis and CRP elevated.

Give your DDx and Tx

Answer 7

Septic Arthritis

• ABX: Ceftriaxone (Meningococcal)/ Ceftriaxone + Azithromycin (Gonococcal)/ ∑ Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (TB)/ Vancomycin (Gram Positive)
–> Pathogen-guided (Empirical)
±
• Surgery: Joint aspiration
±
• Analgesia: Paracetamol/ Ibuprofen/ Diclofenac

Question 8

47 year old diabetic presents with acute onset joint pain, recent fever and has a PMHx of Diabetes Mellitus and OA for which he had a unilateral TKR 3 years ago. He has recently had 4 sexual partners.

His arthrocentesis shows a pathogen present - gram negative diplococci; FBC shows leukocytosis and CRP elevated.

Give your DDx and Tx

Answer 8

Septic arthritis

• ABX: Ceftriaxone (Meningococcal)/ Ceftriaxone + Azithromycin (Gonococcal)/ ∑ Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (TB)/ Vancomycin (Gram Positive)
-> Pathogen-guided (Empirical)
±
• Surgery: TKR
±
• Analgesia: Paracetamol/ Ibuprofen/ Diclofenac

Question 9

State the most common pathogen to cause Osteomyelitis.

Answer 9

S. aureus

Question 10

How do you categorise Osteomyelitis? Give the categories.

Answer 10

• I: Medullary and endosteal
• II: superficial
• III: Medullary and cortical involvement
• IV: Diffuse involvement of entire circumference of bone

Question 11

State 3 pathogens which may cause Osteomyelitis

Answer 11

• S aureus
• S pyogenes
• H influenzae
• Group B streptococci
• Candida spp.
• P aeruginosa

Question 12

A patient presents with pain, fever and malaise. Additionally there is a reduced range of movement in the MCP join which is inflammed, tender and hot.

XR shows periosteal reaction, involucrum, sequestrum and cloacae.

Give your DDx and Tx

Answer 12

Osteomyelitis

• Supportive: Analgesia/ Immobilisation/ Mobilisation/ Specialist referral
+
• ABX