FINAL DIAGNOSIS:
The culture results suggested that the patient's infection was due to M. bovis. Since the patient had had BCG therapy for a bladder neoplasm after the implantation of his prosthesis, the most likely cause of the patient's present infection was dissemination of BCG. Primary
DISCUSSION:
BCG is an attenuated strain of Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex. Albert Calmette and Camille Guerin developed BCG from a virulent strain of
Complications from BCG instillation are uncommon but potentially severe and fatal. These include: fever, granulomatous prostatitis, BCG pneumonitis, BCG hepatitis, hematuria, skin rash, skin abscess, ureteral obstruction, epididymo-orchitis, bladder contracture, hypotension and cytopenia [1,5]. However, 95% of patients have no serious side effects [5]. Arthritis complicating BCG instillation is uncommon (incidence of 0.5% to 3%) [1.9] but well recognized [3,4]. It occurs more frequently in patients expressing HLA B27 [4,6].
Systemic BCG infection may result from traumatic catheterization or treatment following extensive tumor resection [1]. BCG related deaths have occurred following immunization for tuberculosis and following intralesional administration in the treatment of malignancy [1]. Intravesical instillation has also been implicated in BCG related deaths with an estimated mortality of 1 per 12,500 patients [5].
Complications arising from intravesical BCG administration respond well to treatment with anti-tuberculous drugs. Having had exposure to farm animals in Greece and household contact with tuberculosis, this patient may have had any of three possible etiological mycobacterial agents: Mycobacterium tuberculosis, wild type
The first is a multiplex PCR design based on the RD1 region which has been shown to be present in
The other method used is "spoligotyping", or spacer oligotyping, which uses DNA polymorphisms within the chromosomal direct repeat locus of M tuberculosis complex organisms. This region consists of multiple well-conserved 36 bp direct repeat sequences separated by 34 to 41 bp long non-repetitive spacers. The number of direct repeats and presence or absence of certain spacers show strain variation and can identify
This "spoligotyping" method allows for simultaneous detection and strain differentiation of M tuberculosis from clinical samples and can reduce the time for diagnosis and strain differentiation from month(s) to a few days. Previous testing for strain differentiation used DNA-RFLP, but this method is limited by the necessity to culture the organism and is technically demanding.
BCG immunotherapy is the treatment of choice for superficial bladder carcinomas [1,4,5]. Complications arising from its use are numerous and potentially serious.
This case illustrates an example of BCG induced arthritis in a knee prosthesis following immunotherapy for bladder carcinoma. PCR based identification was able to confirm this.
REFERENCES:
Contributed by R Persad, MD, JC Dunn, MD, J Driscoll, MD and W Pasculle, MD