Synergism of imatinib mesylate and everolimus in attenuation of bronchiolitis obliterans after rat LTX

Bronchiolitis obliterans (BO) is a progressive and fatal disease after lung transplantation (LTX). Dysregulated growth factor-induced proliferation of myofibroblasts seems to be responsible for the development of BO. The aim was to confirm the efficacy of both inhibitors of receptor tyrosine kinases (RTKI) and of mammalian target of rapamycin (mTORI) after rat LTX. We used a rat model of left lung allo-transplantation (F344-to-WKY) to evaluate the effect of imatinib (RTKI; 20 mg/kg/day; postoperative day (POD) 0-100) alone or in combination with everolimus (mTORI; 2.5 mg/kg/day; POD 14-100). Non-treated animals were the reference. In non-treated rats, acute rejection (AR) peaked between POD 20 and 30 (19/19) and ended in chronic rejection (CR) on POD 60/100 (12/12). Imatinib alone did not prevent AR (6/6), but attenuated the degree of degenerated bronchioles on POD 30 (non-treated, 57%; imatinib, 4%), and increased the allografts free of CR on POD 60/100 (3/12). A combination of imatinib and everolimus significantly reduced AR, attenuated fibrotic degenerated bronchioles (5%) and vessels (non-treated, 24%; combination therapy, 11%) on POD 30, and reduced fibrotic degenerated vessels (non-treated, 97%; combination therapy, 43%) and bronchioles (non-treated, 88%; combination therapy, 34%) on POD 60/100. Fifty percent of the animals were completely free of BO and vasculopathy. In conclusion, co-application of RTKI and mTORI attenuated the development of BO and vasculopathy. Thus, imatinib might be an interesting therapeutic approach after LTX.

[Extravertebral cement drainage with occlusion of the extradural venous plexus into the vena cava after vertebrobplasty. Case report and review of the literature]

This paper presents the case report of an 88 year old female who came to hospital suffering from a severe lower back pain. Ten days before, she had undergone a vertebroplasty with injection of cement into lumbar vertebra 3 because of an osteoporotic fracture. This treatment did not result in a reduction of the lower back pain, which was the main reason for the procedure. However, the patient claimed to have increasing pain radiating to her left leg. Furthermore, she suffered from numbness of her left leg. Clinical examination showed a lack of power in this leg according to hip flexion with a degree of 3/5. X-ray examinations showed paravertebral cement particles and led to the suspicion that the paravertebral cement had caused nerve root compression. MRI and CT myelography showed that the cement had drained into the intraspinal, extradural venous plexus (Batson's plexus). The plexus was filled out with cement between L2 and L5 on both sides. There was nearly no cement in the fractured vertebra L3, but cement had also run onto the paravertebral veins up to the vena cava, which was also involved. The cemented veins had led to a stenosis of the neuroforamina L2 and L3 on the left side. The result was compression of left L3 nerve root. After consulting with our vascular surgeons, we decided on a non-operative treatment. We prescribed a lumbar brace as external stabilisation and as an antithrombotic treatment we gave the patient weight adapted low molecular weight heparin.