What's the Diagnosis? By Dr. Michael Tom

A 61 yo F w/ a history of schizophrenia presents to the ED w/R middle finger pain. She reports pain and swelling to that digit for 6 months, but both have worsened over the last 2 days and now there is associated redness. An x-ray is obtained. What's the diagnosis?  (scroll down for answer)

 

Answer: Osteomyelitis of R third digit

  • Most cases of osteomyelitits present via contiguous (~80%) or hematogenous (~20%) spread
  • Occurs w/ co-existing septic arthritis in ~15% cases
  • Risk factors include: diabetes, IV drug use, sickle cell diease, recent surgery, bite wounds or extremes of age (pediatrics/elderly)
  • Plain films may be normal early in course, but later will show periosteal elevation, bone demineralization and lytic lesions
  • MRI is 95% sensitive
  • Bone biopsy provides definitive diagnosis
  • Empiric antibiotic coverage should cover for s.aureus (most common causative agent)
  • If patient nontoxic, can discuss with consultant holding antibiotics until culture/biopsy obtained