An 87-year-old Swiss man with German ethnic origin suffered from symptoms of osteoarthritis of the knee. We present the first described case of periprosthetic joint infection after total knee arthroplasty by both Mycobacterium bovis and Candida guilliermondii in the context of a zoonosis with 14 months of follow-up. The infection was presumed to originate more than 55 years earlier when these infectious agents were still present in cattle in Switzerland. After the diagnosis of the pathogens, our patient was successfully treated with tuberculostatic and mycocide medication, and a two-stage revision knee arthroplasty was performed. The medication was given for 1 year. The postoperative course was normal and he achieved ambulant musculoskeletal rehabilitation. After 14 months of follow-up, no further complication emerged. At all routine consultations, there were no indications for joint inflammation, wound healing was normal, and the range of motion was flexion/extension 110/0/0°.
An 87-year-old man from Switzerland with German ethnic origin suffered from symptoms of osteoarthritis of the knee. Preoperatively, there was no suspicion of infectious arthritis. The typical symptoms of osteoarthritis of the knee were present. A routine laboratory test regarding infection parameters (leukocytes, erythrocyte sedimentation rate, C-reactive protein) was without pathological findings. He is a farmer. He grew up on a farm and lived there all his life. He had consumed raw (unpasteurized) milk for years. There was daily contact with animals including cattle. A history of BCG vaccinations was negative. A trip abroad during which an infection could have occurred could be excluded.
The diagnosis was clinically and radiologically confirmed. He had a chronic obstructive pulmonary disease (COPD) stage II and atrial fibrillation and was diagnosed as having deep vein thrombosis some years earlier. No malignant disease or immunodeficiency was known. In November 2014, a TKA was performed: implant, Mathys (Bettlach, Switzerland) balanSys®, Femur D (cemented), Tibia 80 (cemented), Polyinlay 8 mm MB rotating. The initial postoperative course was normal. Our patient was discharged from the hospital after 8 days.
We observed persistent swelling of the knee and persistent wound scab. Aspiration was performed in February 2015, the routine culture was sterile. Two superficial wound debridements were performed in March and April 2015. Following the second debridement, Staphylococcus epidermidis and Corynebacterium were identified. Antibiotic therapy with co-trimoxazole was initiated, there is no antibiotic-free interval. Due to ongoing wound secretion, third wound debridement was performed in May 2015. A defect of the joint capsule was found. We assumed a prosthetic joint infection starting from the wound healing disorder and undertook a one-stage knee replacement. Intraoperatively, there was no osteolytic bone lesion. Taking into account the expected bacterium and considering existing prosthetic material, antibiotic therapy with vancomycin was started.
Tissue samples were obtained and prosthesis sonication was performed. Coagulase-negative staphylococci were detected, and rifampicin (RMP) and clindamycin were given for 3 months. The wound healed after another superficial revision. Eventually, a subcutaneous seroma occurred. Several aspirations were performed, yielding high cell counts (up to 13,000/ml, ≥ 85% neutrophil granulocytes), while routine culture was sterile. Because of the persisting effusion and inflammation, scintigraphy was performed, which demonstrated enhancement in his distal femur.
Because of the persistent inflammation, we decided to perform a knee replacement arthroplasty in two stages. The prosthesis removal was successful and a usual gentamycin Palacos® spacer was implanted in September 2016. We performed tissue sampling and sonication of all implant parts. The materials taken intraoperatively were among others cultured in a liquid medium (BACTEC™ MGIT 960) and on solid media (Löwenstein-Jensen, Middlebrook 7H10-Selective 7H11). The cultures were incubated for 8 to 16 weeks. M. bovis was detected in tissue samples.
A resistance test was performed for the mycostatic drugs isoniazid (INH), RMP, ethambutol (EMB), and pyrazinamide (PZA). Moreover, C. guilliermondii was found by implant sonication. Consequently, the antibiotic therapy was adapted and our patient received RMP, INH, and EMB for 3 months, together with fluconazole for 6 weeks because of the Candida infection. After implant removal, he developed a wound healing disorder, with a fistula anterolateral to the operational area. Therefore, we performed coverage by a pedicled gastrocnemius flap using a split-skin graft. During the above-indicated defect coverage, tissue samples were again collected. Neither Mycobacteria nor Candida was detected.
Ten weeks after prosthesis removal, reimplantation was performed (Fig. 1d) under ongoing antimycobacterial drugs, involving revision TKA: Mathys (Bettlach, Switzerland) balanSys® REVISION, Tibia Stem 140 mm 18 mm Offset 4/11, Tibia Plateau size 75, PE Inlay 18, Femur Stem 140 mm 20 mm, Size C, REV Augmentation 10 medial. We stopped antimycotic treatment after negative culture results. The duration of tuberculostatic therapy was maintained 1 year from revision with RMP, INH, and EMB.
The postoperative course was normal and he achieved ambulant musculoskeletal rehabilitation. After 14 months of follow-up, no further complication emerged. At routine follow-up consultations, there were no indications for joint inflammation, wound healing was normal, and the range of motion was flexion/extension 110/0/0°.