The posterior approach for repair of popliteal artery aneurysms.

OBJECTIVES: Ligation and bypass is the most commonly performed surgical treatment for popliteal artery aneurysm. This approach can be complicated by persistent collateral flow to the excluded aneurysm sac, which may lead to aneurysm growth, the development of compressive symptoms, and in some cases, rupture. Repair of popliteal aneurysms by posterior endoaneurysmorrhaphy and reconstruction with a short prosthetic interposition graft avoids these complications because patent collaterals communicating with the aneurysm sac are oversewn at the time of surgery. We report the early and mid-term outcomes of popliteal artery aneurysm repair using this posterior approach. METHODS: The records of all patients operated on for popliteal artery aneurysm from December 1981 to June 2003 were retrospectively reviewed. Patients who underwent popliteal artery aneurysm repair with a posterior approach were included in the study. RESULTS: From 1981 to 2003, 30 popliteal aneurysms (mean diameter, 3.2 cm; range, 1.9 to 6.2 cm) were repaired in 24 patients using a posterior approach with interposition prosthetic grafting. The median follow up was 21.5 months. Primary patency, primary assisted patency, and secondary patency were 92.2%, 95.8%, and 95.8%, respectively, at 1 and 2 years. The limb salvage rate was 100%. CONCLUSIONS: Popliteal endoaneurysmorrhaphy using a posterior approach with interposition prosthetic grafting is simple, safe, and effective. The patency and limb salvage rates are equivalent to those obtained with ligation and vein bypass. In addition, the posterior approach eliminates the postoperative complications associated with persistent collateral flow into the aneurysm sac.

Bilateral lower extremity gangrene requiring amputation associated with heparin-induced thrombocytopenia--a case report.

Heparin use, both prophylactically and therapeutically, is prevalent among hospitalized patients. Patients on heparin may develop a thrombocytopenia that is self-limited. Fewer patients develop a heparin-induced thrombocytopenia that can cause severe bleeding and thrombosis owing to intravascular platelet aggregation. The authors present a case report of heparin-induced thrombocytopenia in a patient who underwent aortic arch and aortic valve replacement that resulted in bilateral above-knee amputations. The patient developed limb ischemia related to heparin-associated thrombosis, but had a delay in antibody seroconversion. Early and accurate diagnosis of heparin-induced thrombocytopenia requires a high clinical suspicion and may be present despite the absence of serum antibodies.

Renal artery aneurysm secondary to fibromuscular dysplasia in a young patient.

An 8-year-old male was found on routine physical examination to have a blood pressure of 220/110. Renal angiography demonstrated bilateral renal artery stenosis and an aneurysm of the distal left renal artery with branch involvement. At operation, the left renal artery stenosis and aneurysm was repaired by ex vivo arterial reconstruction and autotransplantation of the kidney. Pathologic evaluation of the resected aneurysm confirmed the diagnosis of fibromuscular dysplasia. Fibromuscular dysplasia is the most common cause of renal artery stenosis in children over 1 year of age and can in rare cases be associated with the development of renal artery aneurysms. In complex cases of renal artery stenosis with involvement of renal artery branches, ex vivo repair and orthotopic autotransplantation is an excellent approach for surgical management.

Interleukin-4 receptor cytotoxin as therapy for human malignant pleural mesothelioma xenografts.

BACKGROUND: Malignant pleural mesothelioma (MPM) is an uncommon but highly fatal neoplasm for which only limited treatment is available. METHODS: Immunohistochemical analysis was used to determine the expression of interleukin-4 receptors (IL-4R) on mesothelioma cell lines and resected mesothelioma tumors. Radioreceptor binding assays were used to show that these IL-4R were high-affinity receptors. Previously, we had shown that a chimeric protein composed of a circularly permuted IL-4 molecule fused to a truncated form of Pseudomonas exotoxin A, IL-4(38-37)-PE38KDEL, could be used to kill IL-4R-bearing tumor cells in vitro. The toxicity of this molecule to mesothelioma cell lines was tested using a protein synthesis inhibition assay. A human mesothelioma xenograft model was then developed to assess the efficacy of this molecule in vivo. RESULTS: All MPM cell lines tested were found to express high-affinity cell-surface IL-4R. Immunohistochemical analysis of resected mesothelioma tumor specimens from 13 patients revealed that all tumors expressed moderate-to-high levels of IL-4R. Coculture of malignant mesothelioma cell lines with IL-4(38-37)-PE38KDEL resulted in a dose-dependent inhibition of tumor cell protein synthesis through an interaction with cell-surface IL-4R. In a nude mouse xenograft model of human MPM, intratumoral administration of IL-4(38-37)-PE38KDEL mediated a dose-dependent decrease in tumor volume and a dose-dependent increase in survival. CONCLUSIONS: The chimeric protein, IL-4(38-37)-PE38KDEL, has potent antitumor effects against MPM both in vitro and in vivo.