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Successful treatment of a tuberculous vertebral osteomyelitis eroding the thoracoabdominal aorta: A case report

2005; Elsevier BV; Volume: 42; Issue: 5 Linguagem: Inglês

10.1016/j.jvs.2005.07.011

1097-6809

Juergen Falkensammer, H. Behensky, Hannes Gruber, Wolfgang M. Prodinger, Gustav Fraedrich,

Infective Endocarditis Diagnosis and Management

Mycotic aortic aneurysms are rare complications of systemic tuberculosis that affect very few patients. We report a case of a false aneurysm of the visceral segment of the aorta that was associated with tuberculous vertebral osteomyelitis. Both conditions were successfully treated with antituberculous chemotherapy and a combined surgical procedure, ie, aneurysm resection and homograft implantation, followed by orthopedic stabilization of the spine. Mycotic aortic aneurysms are rare complications of systemic tuberculosis that affect very few patients. We report a case of a false aneurysm of the visceral segment of the aorta that was associated with tuberculous vertebral osteomyelitis. Both conditions were successfully treated with antituberculous chemotherapy and a combined surgical procedure, ie, aneurysm resection and homograft implantation, followed by orthopedic stabilization of the spine. The incidence of infections with Mycobacterium tuberculosis has been increasing worldwide during the last decade. In Western Europe and the United States, current threats from tuberculosis (TB) have basically resulted from three factors: (1) migration from countries with a high TB incidence, (2) the appearance of M tuberculosis strains resistant to the commonly used chemotherapeutic agents, and (3) the continuing increase of the human immunodeficiency epidemic.1Barnes P.F. Barrows S.A. Tuberculosis in the 1990s.Ann Intern Med. 1993; 119: 400-410Crossref PubMed Scopus (207) Google Scholar, 2Raviglione M.C. Snider D.E.J. Kochi A. Global epidemiology of tuberculosis morbidity and mortality of a worldwide epidemic.JAMA. 1995; 273: 220-226Crossref PubMed Scopus (1494) Google Scholar An affection of the spine, also termed Pott disease, occurs in less than 1% of all TB cases.3Rezai A.R. Lee M. Cooper P.R. Errico T.J. Koslow M. Modern management of spinal tuberculosis.Neurosurgery. 1995; 36: 87-98Crossref PubMed Scopus (169) Google Scholar Between 1945 and 2004, only 56 cases of tuberculous aortic aneurysms were published.4Long R. Guzman R. Greenberg H. Safneck J. Hershfield E. Tuberculous mycotic aneurysm of the aorta.Chest. 1999; 115: 522-531Crossref PubMed Scopus (184) Google Scholar, 5Forbes T.L. Harris J.R. Nie R.G. Lawlor D.K. Tuberculous aneurysm of the supraceliac aorta.Vasc Endovasc Surg. 2004; 38: 93-97Crossref PubMed Scopus (11) Google Scholar Accordingly, a combination of both entities is extremely rare. A 61-year-old white man presented at a primary care hospital with a 6-month history of recurrent fever. His disease was diagnosed as miliary TB. A computed tomography (CT) scan revealed spondylodiscitis and a contiguous false aneurysm of the paravisceral aorta, with a maximum diameter of 6.7 cm (Fig 1, Fig 2).Fig 2Computed tomographic scan displaying the aneurysm eroding T11 (*maximum transverse diameter, 67 mm; **maximum sagittal diameter, 55 mm).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Antituberculous chemotherapy was initiated with ethambutol, rifampin, isoniazid, and pyrazinamide. The occurrence of paraparesis on the fifth day after admission indicated the necessity to decompress and stabilize the spine. However, the risk of intraoperative rupture of the contiguous false aneurysm was high. A synchronous repair of both pathologic entities was considered to be adequate treatment. Initially, a temporal extracorporeal left axillofemoral bypass was installed to allow retrograde perfusion of the lower abdominal aorta during the expected prolonged clamping time. A posterolateral thoracoabdominal exposure was performed via an incision along the left ninth intercostal space. After incision of the diaphragm, the descending and suprarenal aorta was isolated, clamped, and incised laterally below the celiac trunk. The false aneurysm arose from a 3 × 4-cm defect in the posterior wall of the aorta. The affected vessel segment was resected, and this left the superior mesenteric artery together with the renal arteries and the celiac trunk on alternate ends of the remaining aortic segments. Reconstruction was performed by using an aortic homograft that had been taken from a donor 15 days earlier and stored at 4°C in a solution for organ preservation (Via Span; Bristol-Myers Squibb GmbH, Regensburg, Germany) containing penicillin G 200,000 U/L. The orthopedic procedure included a subtotal corporectomy of the 11th and 12th thoracic vertebrae and the 1st lumbar vertebra, followed by a partial resection of the posterior walls and meticulous removal of the inflammatory tissue in the spinal canal. Anterior stabilization was performed by use of a titanium mesh cage filled with bone cement, followed by anterior instrumentation of T11 to L2 using a double-screw, double-rod system. The patient was discharged 12 weeks after surgery. A mild weakness of the extensor muscles of the lower extremities remained as a residual neurologic symptom, with normal sensory functions. Antituberculous chemotherapy consisted of pyrazinamide (2 months), isoniazid, rifampin, and ethambutol. Because of bilateral optic neuritis and progressive peripheral neuropathy, antituberculous chemotherapy was discontinued after 5 months. However, magnetic resonance tomography of the spine performed 4 weeks later revealed discitis between the spinal segments T2 and T3 with infiltration of the peridural space. No pathogen could be cultivated from material obtained by CT-guided biopsies. On clinical grounds, antibiotic treatment was restarted with rifampin and pyrazinamide and was terminated after a full course of 12 months. A CT scan performed 15 months after surgery confirmed a regular homograft function with normal perfusion of the enteric and renal arteries. The orthopedic reconstruction had mended and was stable. The focus at the upper thoracic spine was fibrosed and revealed no sign of spinal compression or active inflammation. The visual functions had recovered, but a peripheral neurologic deficit remained. Spinal TB most frequently involves the vertebral bodies of the thoracolumbar spine and the intervening disk spaces.1Barnes P.F. Barrows S.A. Tuberculosis in the 1990s.Ann Intern Med. 1993; 119: 400-410Crossref PubMed Scopus (207) Google Scholar Symptoms are usually slowly progressive and nonspecific and include fatigue, weight loss, fever, and chronic back pain. Neurologic symptoms are found on presentation in 75% of cases and include reduced sensual functions, paraparesis, and impaired vegetative regulation of organ functions. Because symptoms are unspecific and because spinal TB is a rare cause of spinal cord compression, diagnosis is often delayed. Imaging examinations include plain radiographs to visualize the vertebral alignment and major bony destructions. CT scans allow examination of the precise extent of bone involvement. Granulomatous processes within the spinal canal can be visualized by myelography or magnetic resonance imaging.3Rezai A.R. Lee M. Cooper P.R. Errico T.J. Koslow M. Modern management of spinal tuberculosis.Neurosurgery. 1995; 36: 87-98Crossref PubMed Scopus (169) Google Scholar CT-guided needle biopsy and microbiologic identification of M tuberculosis may confirm the diagnosis.3Rezai A.R. Lee M. Cooper P.R. Errico T.J. Koslow M. Modern management of spinal tuberculosis.Neurosurgery. 1995; 36: 87-98Crossref PubMed Scopus (169) Google Scholar For tuberculous spondylodiscitis, therapeutic options include antituberculous medication and external bracing. In the case of even mild neurologic symptoms, marked collapse of the vertebral body, or narrowing of the spinal canal, surgical intervention is recommended.3Rezai A.R. Lee M. Cooper P.R. Errico T.J. Koslow M. Modern management of spinal tuberculosis.Neurosurgery. 1995; 36: 87-98Crossref PubMed Scopus (169) Google Scholar, 6A 10-year assessment of a controlled trial comparing debridement and anterior spinal fusion in the management of tuberculosis of the spine in patients on standard chemotherapy in Hong Kong. Eighth Report of the Medical Research Council Working Party on Tuberculosis of the Spine.J Bone Joint Surg Br. 1982; 64: 393-398PubMed Google Scholar After penetration of the anterior longitudinal ligaments, microbial pathogens may travel along natural tissue plains to infect neighboring structures and organs, including the thoracoabdominal aorta. As a surgical approach, in situ repair, including meticulous surgical debridement, is generally preferred. Primary suture of the pseudoaneurysm and synthetic patch closure have also been performed successfully.4Long R. Guzman R. Greenberg H. Safneck J. Hershfield E. Tuberculous mycotic aneurysm of the aorta.Chest. 1999; 115: 522-531Crossref PubMed Scopus (184) Google Scholar, 5Forbes T.L. Harris J.R. Nie R.G. Lawlor D.K. Tuberculous aneurysm of the supraceliac aorta.Vasc Endovasc Surg. 2004; 38: 93-97Crossref PubMed Scopus (11) Google Scholar Successful endovascular treatment of tuberculous aortic aneurysms has been reported7Liu W.C. Kwak B.K. Kim K.N. Kim S.Y. Woo J.J. Chung D.J. et al.Tuberculous aneurysm of the abdominal aorta endovascular repair using stent grafts in two cases.Korean J Radiol. 2000; 1: 215-218Crossref PubMed Scopus (56) Google Scholar; however, we do favor open surgery, which facilitates debridement of the infected tissue. Debate continues concerning the type of graft material that should be used in infected sites. Experimental studies have shown the advantage of antibiotic-soaked grafts over silver-coated and untreated material.8Hernandez-Richter T. Schardey H.M. Wittmann F. Mayr S. Schmitt-Sody M. Blasenbreu S. et al.Rifampin and Triclosan but not silver is effective in preventing bacterial infection of vascular Dacron graft material.Eur J Vasc Endovasc Surg. 2003; 26: 550-557Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar, 9Ghiselli R. Giacometti A. Goffi L. Cirioni O. Mocchegiani F. Orlando F. et al.Prophylaxis against Staphylococcus aureus vascular graft infection with mupirocin-soaked, collagen-sealed Dacron.J Surg Res. 2001; 99: 316-320Abstract Full Text PDF PubMed Scopus (16) Google Scholar, 10Vicaretti M. Hawthorne W. Ao P.Y. Fletcher J.P. Does in situ replacement of a staphylococcal infected vascular graft with a rifampicin impregnated gelatin sealed Dacron graft reduce the incidence of subsequent infection?.Int Angiol. 2000; 19: 158-165PubMed Google Scholar Vascular allografts have been used for aortic reconstruction in infected areas with good short- and long-term results; they decrease the risk of graft infection compared with untreated vascular prostheses.11Vogt P.R. Brunner-La Rocca H.P. Carrel T. von Segesser L.K. Ruef C. Debatin J. et al.Cryopreserved arterial allografts in the treatment of major vascular infection a comparison with conventional surgical techniques.J Thorac Cardiovasc Surg. 1998; 116: 965-967Abstract Full Text Full Text PDF PubMed Scopus (117) Google Scholar, 12Vogt P.R. von Segesser L.K. Goffin Y. Pasic M. Turina M.I. Cryopreserved arterial homografts for in situ reconstruction of mycotic aneurysms and prosthetic graft infection.Eur J Cardiothorac Surg. 1995; 9: 502-506Crossref PubMed Scopus (71) Google Scholar, 13Knosalla C. Weng Y. Yankah A.C. Hofmeister J. Hetzer R. Using aortic allograft material to treat mycotic aneurysms of the thoracic aorta.Ann Thorac Surg. 1996; 61: 1146-1152Abstract Full Text PDF PubMed Scopus (69) Google Scholar However, no data exist comparing long-term results of homografts vs antibiotic-bonded vascular prostheses. Our results using homografts that are stored for a maximum of 4 weeks at 4°C in a solution for organ preservation are excellent. Because of the high numbers of organ transplantations performed at our institution, vascular homografts are frequently available for the treatment of graft infections and mycotic aneurysms (unpublished data). After surgery, patients receive bacteriogram-guided antibiotic treatment for 6 to 12 weeks. In the case of pulmonary and extrapulmonary TB caused by a fully susceptible pathogen, a 6-month combination therapy consisting of isoniazid, rifampin, ethambutol, and pyrazinamide for the initial 2 months and another 4 months with isoniazid and rifampin is currently recommended.14Blumberg H.M. Burman W.J. Chaisson R.E. Daley C.L. Etkind S.C. Friedman L.N. et al.American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America treatment of tuberculosis.Am J Respir Crit Care Med. 2003; 167: 603-662Crossref PubMed Scopus (1647) Google Scholar The prolonged application of antituberculous medication for 12 months was indicated by the recurrence that we encountered in this case. Tuberculous aortic aneurysms are a rare but potentially devastating complication of infections with M tuberculosis. In this case of a patient with a combined tuberculous spondylodiscitis and tuberculous aortic aneurysm, an aortic reconstruction using homograft material followed by debridement and stabilization of the spine and adequate antimicrobial chemotherapy was successfully performed.