A 9-year-old boy with sickle cell disease presents with fever and severe pain over the mid-diaphysis of the tibia for 5 days. WBC 16,000, ESR 80. MRI confirms acute osteomyelitis. Which organism is MOST likely responsible, and what is the recommended first-line antibiotic?

• A Staphylococcus aureus; cloxacillin or flucloxacillin
• B Streptococcus pneumoniae; penicillin G
• C Salmonella species; ciprofloxacin or co-trimoxazole ✓
• D Pseudomonas aeruginosa; piperacillin-tazobactam

Explanation

While Staphylococcus aureus remains the most common cause of osteomyelitis overall, in sickle cell disease Salmonella species (especially Salmonella typhi and paratyphi) are the MOST COMMON cause — the functional asplenia and impaired opsonisation in sickle cell patients create susceptibility to encapsulated and intracellular pathogens like Salmonella. Treatment is with ciprofloxacin or co-trimoxazole. Staph. aureus is still possible but second in frequency in this specific context, and this distinction is repeatedly tested in NEET PG.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.