□ CASE REPORT □

A Rare but Potentially Lethal Case of Tuberculous Aortic Presenting with Repeated Attacks of Abdominal Pain

Yao-Min Hung 1-3, Yun-Te Chang 1-3, Jyh-Seng Wang 2,4, Paul Yung-Pou Wang 5 and Shue-Ren Wann 1-3

Abstract

Tuberculous is an extremely rare disease with a high mortality rate. The clinical features of this condition are highly variable, ranging from asymptomatic with or without constitutional symptoms, abdominal pain to frank rupture, bleeding and shock. We herein report the case of a 56-year-old man with a large tuberculous mycotic aneurysm in the abdominal with an initial presentation of repeated attacks of abdominal pain lasting for several months. Due to the vague nature of the initial symptoms, tuberculous aor- tic may take several months to diagnose. This case highlights the importance of having a high in- dex of suspicion and providing timely surgery for this rare but potentially lethal disease.

Key words: abdominal aortic aneurysm, abdominal pain, aneurysm, aorta, mycotic aneurysm, tuberculosis

(Intern Med 54: 1145-1148, 2015) (DOI: 10.2169/internalmedicine.54.3620)

a 56-year-old man who presented to the ED with repeated Introduction attacks of abdominal pain. Following a preoperative evalu- ation, including clinical and radiological assessments, he un- Tuberculosis (TB) remains a major global health problem. derwent successful repair of a mycotic aneurysm in the ab- This disease causes ill-health in millions of people each year dominal aorta with excision and replacement of the diseased and ranks as the second leading cause of death from infec- aorta. A postoperative biopsy showed a tuberculous aortic tious disease. The latest estimates from the World Health aneurysm, and he was started on antituberculous chemother- Organization include 8.6 million new TB cases and 1.3 mil- apy based on the histological findings. lion TB deaths worldwide in 2012 (1). TB may have a wide range of clinical presentations due to its disseminative prop- Case Report erties, with both contiguous and hematogenous routes. Aor- tic involvement secondary to TB is exceedingly rare and A 56-year-old man was brought to our ED with abdomi- may occur in the form of or aneurysm forma- nal pain lasting for 10 days. He had a history of hyperten- tion (2, 3). Whether by direct extension or via the blood sion under medication control. According to his statement, stream, a focus of aortitis becomes established, and the aor- he had no previous tuberculous exposure. He also denied tic wall experiences destruction (2). Symptomatic tubercu- any possibility of relevant household contact, eating habits lous mycotic aneurysm is an extremely rare but uniformly or ownership of unusual pets, such as reptiles. He had vis- fatal lesion if not diagnosed promptly (3, 4). Abdominal ited several clinics and local hospitals for help within the pain is a common chief complaint among patients who visit past two to three months, receiving various diagnoses. He the emergency department (ED).We herein report the case of had also been treated by general practitioners, but never had

１Department of Emergency Medicine, Kaohsiung Veterans General Hospital, Taiwan, ２School of Medicine, National Yang-Ming University, Taiwan, ３Yuhing Junior College of Health Care and Management, Taiwan, ４Department of Pathology, Kaohsiung Veterans General Hospital, Taiwan and ５Division of Nephrology, Kaiser Permanente Baldwin Park Medical Center, U.S.A. Received for publication July 7, 2014; Accepted for publication September 15, 2014 Correspondence to Dr. Shue-Ren Wann, [email protected]

1145 Intern Med 54: 1145-1148, 2015 DOI: 10.2169/internalmedicine.54.3620

Table. Results of the Patient’s Laboratory Data on Admission

Variable Patient’s results Normal range WBC (/mm3) 9,590 4,000-9,900 Neutrophils (% ) 88 41-73 Hb (g%) 14.4 12-15 PLT(×1000 /mm3) 275 150- 450 GPT (U/L) 18 0-40 ALP (U/L) 85 42-128 BUN(mg/dL) 14 7- 20 Serum creatnine(mg/dL) 0.7 0.5- 1.5 Sodium (mEq/L) 140 135-147 Potassium(mEq/L) 4.0 3.4- 4.7 Glucose (mg/dL) 193 65- 200 CRP (mg/dL) 11.5 <0.8 WBC: White blood cells, Hb: Hemoglobin, PLT: platelet count, GPT: glutamic pyruvate transaminase, GOT: glutamic oxaloacetic acid transaminase, ALP: alkaline phosphatase, Figure 1. Abdominal computed tomography showing a sac- BUN: blood urea nitrogen, and CRP: C-reactive protein cular mycotic aneurysm involving the abdominal aorta, infra- renal type, with a mural hematoma (sagittal view).

Figure 2. Abdominal computed tomography showing a sac- Figure 3. Histopathology of the aortic aneurysm showing cular mycotic aneurysm involving the abdominal aorta, infra- features of granulomatous and focal caseous ne- renal type, with a mural hematoma (transverse view). crosis (Hematoxylin and Eosin staining, ×200). a complete workup. His vital signs were as follows: blood quent rupture, a potentially lethal complication. Therefore, pressure= 168/98 mmHg, rate= 75 beats per minute, the patient underwent surgery, and a biopsy showed features respirations= 16 per minute and body temperature= 37.5°C. of chronic granulomatous inflammation and focal caseous A physical examination of the chest was normal, and the ab- necrosis, consistent with TB infection, which confirmed the domen was soft and mildly tender diffusely with no evi- diagnosis (Fig. 3, 4). He was thus started on a four-drug an- dence of rebound or guarding. A rectal examination revealed tituberculous regimen (isoniazid, rifampin, ethambutol, hard stools, but no masses or . The laboratory pyrazinamide), and the aneurysm cultures eventually grew data obtained on admission are shown in Table; only in- mycobacterium TB resistant to isoniazid. He has since been creased an C-reactive protein (CRP) level was found. A rou- followed up regularly at our outpatient department. Further tine urinalysis was negative, and an electrocardiogram CT scans showed negative findings. showed a normal sinus rhythm at 87 beats/min. Chest and abdomen roentgenograms showed no abnormalities; how- Discussion ever, abdominal computed tomography (CT) revealed a 6- cm mycotic aneurysm involving the abdominal aorta, infra- Aneurysms are a very rare complication of TB. With re- renal type (Fig. 1, 2). As typical organisms, such as the Sal- spect to extrapulmonary TB, tuberculous aortic aneurysm monella species or Staphylococcus aureus, were suspected at formation is considered a rare form of TB. The largest series the time, the patient received empirical intravenous antibiot- review from 1945 to 1999 found only a total of 39 cases in ics and was admitted to the intensive care unit. the published literature (3), and Kamen first reported this There was evidence of a significant mycotic aneurysm on devastating complication of TB in 1858 (5). Volini et al. a CT scan of the abdomen, with the possibility of subse- later described the pathophysiology of aortic TB, in which a

1146 Intern Med 54: 1145-1148, 2015 DOI: 10.2169/internalmedicine.54.3620

infected mycotic aneurysms, such as invasive infections with Salmonella species or Staphylococcus aureus. Tuberculous aortic aneurysms are diagnosed based on the detection of the growth of organisms in culture or histologi- cal features or both. TB has already been diagnosed at pres- entation in 63% of patients, and disseminated TB is present in 46% of cases (3). Our patient had no history of TB, and CXR findings were negative. The only hint to the presence of an aneurysm was the persistence of abdominal pain last- ing for 10 days. Due to the varied presentation and often nonspecific nature of the signs and symptoms of aortitis, the index of suspicion must be high in order to establish an ac- Figure 4. Histopathology of the aortic aneurysm showing curate diagnosis in a timely fashion. In particular, the differ- positive staining for acid-fast bacilli (Hematoxylin and Eosin ential diagnosis includes various infected mycotic aneurysms staining, ×1,000). that should be ruled out before surgery. In addition, the di- agnosis of tuberculous aortitis is very difficult to establish, as the disorder is exceedingly rare and can mimic Takayasu primary tuberculous focus in the lungs involves periaortic arteritis (11). For these reasons, the diagnosis may be de- structures in the first pathologic stage, subsequently causing layed and the patients may be treated with immunosuppres- lymphadenitis, pericarditis, empyema, spondylitis and/or sive therapy before the diagnosis of TB is established. paravertebral abscesses. Later, tubercle bacilli may invade Therefore, the possibility of tuberculous aortitis should be the aortic wall. The second pathway involves hematogenous considered in patients with aortitis or atypical aortic aneu- dissemination. Whether by direct extension or via the blood rysms who have a history of pulmonary or extrapulmonary stream, a focus of aortitis becomes established and the aortic TB and/or chronic immunosuppression (8). In the current wall exhibits destruction (6). The speed of progression var- case, a definitive diagnosis was not obtained before surgery, ies (2), and treating this condition is challenging due to at and infection with typical organisms, such as Salmonella least two factors. First, great imitators of TB are common, species or Staphylococcus aureus, was favored based on our and second, tuberculous aortic aneurysms are prone to previous experience. In addition, in a past case report, the abrupt rupture and underdiagnosis is possible until post- rapid progression of bacterial aortitis to an ascending aortic mortem pathology findings can be obtained. mycotic aneurysm was documented on transesophageal The syndromic diagnosis in this case may be called echocardiography within six days (12). “chronic periaortitis,” which is characterized by the presence Managing tuberculous aortic aneurysms is challenging, of inflammation and fibrosis surrounding the aorta and typi- and the standard therapeutic strategy has not yet been estab- cally involves the infrarenal portion of the abdominal lished (13). Open aortic reconstructive surgery is generally aorta (7). This disease is rare, usually occurring in middle- considered to be the standard of treatment for aortic aneu- aged men. In the current case, the patient noted the initial rysms associated with aortitis, although endovascular tech- presentation of repeated attacks of abdominal pain for sev- niques have recently been employed, with early reported eral months. In addition, there was no past history of TB, successes (13-15). While endovascular treatment has the and chest X-ray (CXR) was negative. Furthermore, the in- theoretical advantage of avoiding extensive manipulation of itial laboratory abnormality was increased CRP, which is inflamed aortic tissue, thus preventing the morbidity and nonspecific. Abdominal CT favored a diagnosis of an aortic mortality associated with open surgery, there are downsides mycotic aneurysm. One of the important differential diagno- in patients with TB-infected aneurysms. In such cases, de- ses within this disease spectrum is retroperitoneal fibrosis, spite placement of the stent graft at the site of primary in- which may be idiopathic or secondary to other causes. fection, prospective complications include persistent bactere- Chronic periaortitis also includes inflammatory abdominal mia, reinfection, delayed rupture, paraplegia, distal emboli aortic aneurysms and perianeurysmal retroperitoneal fibrosis. and surgical conversion. Some authors maintain that endo- These entities are grouped together due to their similar clini- vascular stenting is feasible if antibiotic suppression results cal and histologic characteristics. An imaging appearance in negative blood cultures before the intervention (16). similar to that of retroperitoneal fibrosis is often observed in Hence, the use of endovascular repair remains controver- cases of abdominal aortic aneurysms, with tumors inducing sial (13), and there have been no head-to-head trials of the a desmoplastic response, including lymphomas, sarcomas optimal strategy for managing aortic aneurysms in patients and pancreatic carcinomas (7-10). These important differen- with aortitis. tial diagnoses should be considered and ruled out before Infectious aortitis is a rare clinical entity most often asso- surgery. Our patient initially also received empirical intrave- ciated with abdominal aortic aneurysms. However, very few nous antibiotics and was admitted to the intensive care unit, cases of tuberculous aortic aneurysm have been reported; to as the differential diagnosis also included several kinds of our knowledge, there are only 75 cases in the English lan-

1147 Intern Med 54: 1145-1148, 2015 DOI: 10.2169/internalmedicine.54.3620 guage literature on PubMed from 1945 to 2011 (13). An- sis: still an enigma. Presenting as mycotic aneurysm of aorta. BMJ other point deserving attention is there are two extremes in Case Rep (in press). 5. Kamen L. Aortenruptur auf tuberculouer Grundlage. Beitr Pathol the disease presentation: initial nonaneurysmal aortitis and Anat 17: 416-419, 1895. mycotic aneurysms (17). It is unclear how long patients de- 6. Volini FI, Olfield RC Jr, Thompson JR, Kent G. Tuberculosis of velop tuberculous aortic aneurysms after the initial onset of the aorta. JAMA 181: 78-83, 1962. possible nonaneurysmal aortitis. Nevertheless, the small 7. Vaglio A, Buzio C. Chronic periaortitis: a spectrum of diseases. number of cases of nonaneurysmal infectious aortitis re- Curr Opin Rheumatol 17: 34-40, 2005. ported in the literature and rarity of the disease in patients 8. Gornik HL, Creager MA. Aortitis. Circulation 117: 3039-3051, 2008. with TB can be attributed to underdiagnosis and delayed di- 9. Vaglio A, Salvarani C, Buzio C. Retroperitoneal fibrosis. Lancet agnosis. 367: 241-251, 2006. It is very important to establish an early diagnosis of in- 10. Scheel PJ Jr, Feeley N. Retroperitoneal fibrosis: the clinical, labo- fectious aortitis using adequate image studies in patients ratory, and radiographic presentation. Medicine (Baltimore) 88: presenting with unexplained and repeated attacks of 202-207, 2009. 11. Gajaraj A, Victor S. Tuberculous aortoarteritis. Clin Radiol 32: abdominal pain. The pathophysiology of this disease sug- 461-466, 1981. gests that infectious aortitis and mycotic aneurysms repre- 12. Wein M, Bartel T, Kabatnik M, Sadony V, Dirsch O, Erbel R. sent extremes along the spectrum of the same disease. Al- Rapid progression of bacterial aortitis to an ascending aortic my- though establishing a diagnosis of aortic infection before cotic aneurysm documented by transesophageal echocardiography. aneurysm formation or rupture is very difficult, it is essen- J Am Soc Echocardiogr 14: 646-649, 2001. 13. Wang Y, Zhang J, Yin MD, Wang SY, Duan ZQ, Xin SJ. Endo- tial for preventing devastating complications. vascular repair of a tuberculous aneurysm of descending thoracic aorta. Chin Med J (Engl) 124: 2228-2230, 2011. The authors state that they havenoConflictofInterest(COI). 14. Labrousse L, Montaudon M, Le Guyader A, Choukroun E, Laurent F, Deville C. Endovascular treatment of a tuberculous in- fected aneurysm of the descending thoracic aorta: a word of cau- References tion. J Vasc Surg 46: 786-788, 2007. 15. Liu WC, Kwak BK, Kim KN, et al. Tuberculous aneurysm of the 1. WHO. Tuberculosis (TB). Geneva; World Health Organization, abdominal aorta: endovascular repair using stent grafts in two 2013. GLOBAL TUBERCULOSIS REPORT 2013. [Internet]. cases. Korean J Radiol 1: 215-218, 2000. [cited 2014 Mar 18]. Available from: https:www.who.int/tb/publica 16. Celia R, Colin B, Ravul J, Nicholas C, Mohamad H. Endovascular tions/global_report/gtbr12_main.pdf stenting of peripheral infected aneurysms: a temporary measure or 2. Volini FI, Olfield RC Jr, Thompson JR, Kent G. Tuberculosis of a definitive solution in high-risk patients. Cardiovasc Intervent Ra- the aorta. JAMA 181: 78-83, 1962. diol 31: 1228-1235, 2008. 3. Long R, Guzman R, Greenberg H, Safneck J, Hershfield E. Tuber- 17. Lopes RJ, Almeida J, Dias PJ, Pinho P, Maciel MJ. Infectious tho- culous mycotic aneurysm of the aorta. Chest 115: 522-531, 1999. racic aortitis: a literature review. Clin Cardiol 32: 488-490, 2009. 4. Kolhari VB, Bhairappa S, Prasad NM, Manjunath CN. Tuberculo-

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