Mycobacterium thermoresistibile Infection following Knee-Replacement Surgery

Abstract

We report a case of Mycobacterium thermoresistibile as a cause of infection following total knee replacement. This infection was masked by the prior isolation of a vancomycin-resistant enterococcus. The infection was resolved with long-term therapy using moxifloxacin and doxycycline. CASE REPORTA 73-year-old female patient who underwent a bilateral total knee replacement developed pain and swelling in the left knee and fevers 2 months after surgery. She was seen 1 week prior to admission at another facility, where material draining from the incision site was cultured. These cultures grew a vancomycin-resistant Enterococcus faecium isolate (VRE). The patient was placed on linezolid and transferred to our hospital for removal of the infected prosthetic joint.On admission the patient appeared well, with a tender left knee with a decreased range of motion and drainage from the incision site. The patient has a history of diabetes mellitus. Her laboratory values were significant only for a white blood cell count of 11.1/l, a platelet count of 619/l, an erythrocyte sedimentation rate of 90 mm/h, and a C-reactive protein level of 16.3 mg/liter. The patient was taken to the operating room for removal of the prosthetic joint. A washout of the left knee was also performed at this time. Linezolid therapy was withheld prior to surgery but restarted immediately after the procedure was performed. Tissue sections obtained perioperatively were sent for pathological examination and for bacteriological, mycological, and mycobacterial culture. Pathological examination of synovial tissue revealed chronically inflamed granulomatous tissue with fibrinous exudates, tissue necrosis, and acute inflammation. Special stains for acid-fast bacilli were negative. Gram and acid-fast stains prepared from the specimens sent for microbiological culture were negative. Routine bacteriology and mycology cultures were negative. The patient was discharged on a 6-week course of linezolid for a presumed VRE infection. After 3 weeks of incubation at 35°C, the Lowenstein-Jensen agar slant showed scant growth of a chromogenic acid-fast bacillus. This was followed by the detection of growth in the VersaTREK Myco bottle (Trek Diagnostic Systems, Cleveland, OH) a short time later. The resulting growth from the Myco bottle was identified using the Sherlock MIDI high-performance liquid chromatography system (MIDI, Newark, DE) as Mycobacterium thermoresistibile.The identification was confirmed using biochemical tests and the ability of the isolate to grow at 52°C. This isolate was positive for nitrate reduction and negative for both tellurite reduction and iron uptake.Susceptibility tests were performed utilizing Sensititre microtiter plates (Trek Diagnostic Systems) with Middlebrook 7H9 broth incubated at 42°C. For this method, a 0.5 McFarland standard suspension of the isolate is made and the manufacturer's instructions are followed depending on the panel type utilized, with 7H9 broth used in place of Mueller-Hinton broth. The resulting MICs were as follows: m...

Mycobacterium barrassiae sp. nov., a Mycobacterium moriokaense Group Species Associated with Chronic Pneumonia

“…Among the rapidly growing mycobacteria (RGM), the species most commonly recovered from patients belong to the Mycobacterium chelonae-Mycobacterium abscessus, Mycobacterium mucogenicum, Mycobacterium fortuitum, Mycobacterium mageritense, Mycobacterium wolinskyi, and Mycobacterium smegmatis groups (1,2,3,4,5,6,7,10,11,31,43,44). Rarely encountered species include Mycobacterium novocastrense, which is responsible for cutaneous infections (33); Mycobacterium hodleri, which causes opportunistic infections in the course of rheumatoid arthritis (40); Mycobacterium neoaurum, which was isolated from a patient with catheter-related bacteremia (46); Mycobacterium flavescens, which caused a disseminated infection in a probable case of chronic granulomatous disease (8); and Mycobacterium thermoresistible, which was responsible for an infection following kneereplacement surgery (20). Other species were isolated from human samples, such as Mycobacterium hassiacum from urine (32); Mycobacterium elephantis from the sputum and granulomatous tissue of an axillary lymph node (26,37,39); Mycobacterium doricum from cerebrospinal fluid (38); Mycobacterium brumae from sputum and a case of catheter-related bacteremia (21,22); Mycobacterium brisbanense from the antral sinus (31); Mycobacterium confluentis from sputum (17); Mycobacterium holsaticum from sputum, urine, and gastric fluid (28); Mycobacterium cosmeticum from a footbath drain and a granulomatous subdermal lesion in a female patient who was undergoing mesotherapy (12); and Mycobacterium canariasense from the blood of a patient with febrile syndrome (15).…”

Infection Due to Mycobacterium thermoresistibile: a Case Associated with an Orthopedic Device

“…Previously, only one case of M. thermoresistibile infection related to an orthopedic device had been reported (Table 1) (13). The treatment included the removal of the prosthesis and longterm antibiotics, as in our case (13).…”

“…The treatment included the removal of the prosthesis and longterm antibiotics, as in our case (13). While no guidelines existed for the treatment of M. thermoresistibile infections, our choice of antibiotics was based on susceptibility testing and on ATS guidelines for NTM infections (14).…”

Mycobacterium Thermoresistibile: Case Report of a Rarely Isolated Mycobacterium From Europe and Review of Literature

“…On the contrary, in cases of cutaneous specimens, laboratories usually incubate specimens at 30 o C on media capable of growing M. haemophilum as well as other pathogens typically associated with skin infections. [16] Another reason for its rare isolation is that identifying M. thermoresistibile, based on its phenotypic and biochemical profile, is difficult as it shares common features with other mycobacteria such as M. phlei, M. flavescens or M. gordonae (not an RGM). [14,15] Moreover, the currently available commercial diagnostic kits do not include species-specific probes for M. thermoresistibile.…”

“…[16] The infection was masked by prior isolation of a vancomycinresistant enterococcus. M. thermoresistibile was identified with biochemical tests and HPLC.…”