Arthrology and Infections

Arthrology and Infections Indian Medical PG Question 1: A 12 year old girl was brought with fever, malaise, and migrating polyarthritis. She had a history of recurrent throat infections in the past. Elevated erythrocyte sedimentation rate is noted. Which among the following is NOT a major Jones criteria for diagnosis of acute rheumatic fever?

• A. Raised ESR (Correct Answer)
• B. Chorea
• C. Arthritis
• D. Carditis

Arthrology and Infections Explanation: ***Raised ESR*** - **Elevated erythrocyte sedimentation rate (ESR)** is a **minor criterion** in the Jones Criteria for acute rheumatic fever, indicating inflammation but not specific enough to be a major criterion. - While it supports the diagnosis, it is a non-specific inflammatory marker rather than a distinct clinical manifestation of the disease. *Chorea* - **Sydenham's chorea** (St. Vitus' dance) is a **major manifestation** of acute rheumatic fever, characterized by involuntary, purposeless movements. - It results from central nervous system involvement and is a highly diagnostic sign, often appearing late in the disease course. *Arthritis* - **Migratory polyarthritis** is a **major criterion** for acute rheumatic fever, typically affecting large joints in a sequential pattern. - This symptom is often the presenting complaint and is highly responsive to anti-inflammatory treatment. *Carditis* - **Carditis**, involving inflammation of the heart muscle, pericardium, or endocardium, is a **major criterion** and the most serious manifestation of acute rheumatic fever. - It can lead to long-term valvular damage, particularly affecting the mitral and aortic valves.

Arthrology and Infections Indian Medical PG Question 2: Tom-smith arthritis results from

• A. Staphylococcus aureus infection (Correct Answer)
• B. Streptococcus pyogenes infection
• C. Haemophilus influenzae infection
• D. Escherichia coli infection

Arthrology and Infections Explanation: ***Staphylococcus aureus infection*** - **Tom-smith arthritis** (more commonly known as **septic arthritis** or infectious arthritis) is most frequently caused by **Staphylococcus aureus**, especially in adults and older children [1]. - The bacteria can enter the joint directly via trauma, surgery, or spread hematogenously from a distant infection, leading to rapid joint destruction if untreated [1]. *Streptococcus pyogenes infection* - While **Streptococcus pyogenes** can cause infectious arthritis, it is a less common cause than **Staphylococcus aureus** [1]. - It is more classically associated with **rheumatic fever** following pharyngitis, which involves migratory polyarthritis but is an immunologically mediated process, not direct bacterial infection of the joint in the same way. *Haemophilus influenzae infection* - **Haemophilus influenzae type b (Hib)** was once a common cause of septic arthritis in unvaccinated children but is now rare due to widespread vaccination. - In adults, other bacterial causes are more prevalent for septic arthritis. *Escherichia coli infection* - **Escherichia coli** can cause septic arthritis, particularly in neonates, immunocompromised individuals, or following genitourinary tract infections or intra-abdominal sepsis. - However, it is less common than **Staphylococcus aureus** as the primary cause of acute septic arthritis in otherwise healthy adults.

Arthrology and Infections Indian Medical PG Question 3: What is the most cost-effective screening strategy for STIs in resource-limited settings according to WHO guidelines?

• A. Risk-based screening
• B. Periodic mass treatment
• C. Syndromic management (Correct Answer)
• D. Universal screening

Arthrology and Infections Explanation: ***Syndromic management*** - This approach involves diagnosing and treating STIs based on the **clinical symptoms** presented by the patient, without the need for expensive laboratory tests. - It is highly cost-effective in resource-limited settings as it reduces the need for costly diagnostics while ensuring prompt treatment to prevent complications and onward transmission. *Risk-based screening* - While helpful, identifying high-risk individuals and conducting targeted screening still requires some level of diagnostic testing, which can be **expensive** or **unavailable** in resource-limited settings. - It may miss STIs in individuals who do not fit predefined risk categories but are still infected. *Periodic mass treatment* - This strategy involves treating a large population group for STIs regardless of their symptom status, which can lead to **antimicrobial resistance** and is not specifically recommended by WHO for routine STI control. - It is generally **inefficient** and potentially wasteful of resources, as many individuals treated may not be infected. *Universal screening* - This approach involves comprehensive diagnostic testing for all individuals, which is highly effective but **prohibitively expensive** and logistically challenging for resource-limited settings. - It requires significant infrastructure for laboratory testing and follow-up, which is often lacking where resources are scarce.

Arthrology and Infections Indian Medical PG Question 4: Which one of the following is the antibiotic of choice for the prevention of Rheumatic Heart Disease?

• A. Benzathine Benzyl Penicillin (Correct Answer)
• B. Doxycycline
• C. Procaine Penicillin
• D. Ciprofloxacin

Arthrology and Infections Explanation: ***Benzathine Benzyl Penicillin*** - It is the antibiotic of choice for the **prevention of Rheumatic Heart Disease (RHD)** due to its **long-acting nature** and effectiveness against **Group A Streptococcus (GAS)**. - A single intramuscular injection provides **sustained therapeutic levels** for several weeks, crucial for preventing recurrent GAS infections that lead to RHD. *Doxycycline* - Not effective for **primary prevention of Rheumatic Fever** or RHD as it is not a first-line agent against **Group A Streptococcus**. - Mainly used for **atypical bacteria** and certain parasitic infections. *Procaine Penicillin* - It has a shorter duration of action compared to **benzathine penicillin**. - Requires more frequent injections, making it less suitable for **long-term prophylaxis** in RHD prevention. *Ciprofloxacin* - This is a **fluoroquinolone antibiotic** and is not the antibiotic of choice for **Group A Streptococcus infections**. - Its use in this context could contribute to **antibiotic resistance** without providing effective prophylaxis for RHD.

Arthrology and Infections Indian Medical PG Question 5: When do we have to start antibiotics to prevent post-operative infection?

• A. 1 week before surgery
• B. 2 days before surgery
• C. After surgery
• D. 30-60 minutes before incision (up to 24 hours post-op) (Correct Answer)

Arthrology and Infections Explanation: ***30-60 minutes before incision (up to 24 hours post-op)*** - Surgical antibiotic prophylaxis (SAP) should be administered **30-60 minutes before surgical incision** to ensure adequate tissue and serum concentrations at the time of incision. - This timing allows optimal drug distribution to surgical tissues, which is crucial for preventing surgical site infections (SSIs). - For most clean and clean-contaminated surgeries, prophylaxis should be limited to a **single dose** or continued for **maximum 24 hours post-operatively** as per WHO and CDC guidelines. - Prolonged post-operative antibiotics beyond 24 hours do **not** reduce infection rates and increase the risk of **antibiotic resistance** and **adverse effects**. *1 week before surgery* - Administering antibiotics this far in advance is **unnecessary** and **ineffective** for surgical prophylaxis. - It increases the risk of **antibiotic resistance** and does not guarantee adequate drug levels at the time of incision. - Pre-operative antibiotic use should be avoided unless treating an active infection. *2 days before surgery* - This timeframe is too early to achieve prophylactic benefit during the surgical procedure. - Prolonged pre-operative use promotes **bacterial resistance** without providing additional protection. - Drug levels will not be optimal at the time of incision due to metabolism and excretion. *After surgery* - Starting antibiotics **after surgical incision** is **too late** for prophylaxis as contamination has already occurred. - Post-operative initiation is considered **therapeutic treatment** for established infection, not prevention. - The critical window for prophylaxis is the period from skin incision to wound closure.

Arthrology and Infections Flashcard 1 of 5

Question: Septic arthritis needs to be treated immediately to prevent the destruction of _____.

Answer: articular cartilage

Arthrology and Infections Flashcard 2 of 5

Question: _____ is the most common cause of septic arthritis in adults

Answer: Staphylococcus aureus

Arthrology and Infections Flashcard 3 of 5

Question: A patient with an effusion in the hip joint is most comfortable in _____ and abducted position.

Answer: flexed

Arthrology and Infections Flashcard 4 of 5

Question: _____ knee is also known as infrapatellar bursitis

Answer: Clergyman's

Arthrology and Infections Flashcard 5 of 5

Question: Patients with psoas abscesses frequently position themselves to minimize psoas stretching and discomfort by engaging hip _____ and positioning into lumbar lordosis

Answer: flexion