TUBERCULOSIS, AN IMPORTANT DIFFERENTIAL DIAGNOSIS IN PROSTHETIC HIP INFECTION

Abstract

Introduction: The incidence of tuberculosis has increased by almost 30% annually in the UK. Orthopaedic surgeons are more likely to encounter patients affected with Mycobacterium tuberculosis [MTB]. We have reviewed the surgical and medical management of cases of MTB infecting prosthetic hip joints in patients without previous tuberculosis.

Report: A 59 year old Caucasian woman presented to us with apparent osteoarthritis hip. X-rays confirmed osteoarthritis but also revealed a lytic lesion in the greater trochanter and erosion of the superior cortex of the femoral neck. The patient had no prior history of exposure to tuberculosis and no evidence of pulmonary or osteoarticular tuberculosis. The patient was investigated preoperatively with blood tests, bone scan, CT scan, CT guided FNAC, and core biopsy. None of these showed any specific diagnostic features. She underwent a total hip replacement and was asymptomatic up to 15 months post-op when she presented with pain in the joint with an abscess over the gluteal region. The abscess was drained and special media culture grew MTB. We used 4-drug therapy for 12 months with retention of the prosthesis and a good functional result.

Discussion: Infected total hip replacement presents a management challenge and surgeons should have a high index of suspicion for Tuberculosis in recalcitrant infections where smears from infected joints are negative. The infection of a total hip replacement with MTB in patients without previous tuberculosis is very uncommon. Only 12 cases have been reported in a search of English language literature from 1966–2005.

We have analysed the wide variation in the management of these cases. The majority of authors in our review resected or revised the infected prosthesis. We are of the opinion that if the infection is clinically under control and the prosthesis is stable, medical treatment alone should suffice.