A 84-year old man of Greek origin, retired farmer and former smoker, with a possible history of tuberculosis in his childhood, was admitted to hospital with low-grade fever and febrile episodes up to 38.5  C, with concomitant weight loss of about 12Kg during the last 3 months. The clinical examination did not reveal any focal symptoms, while the chest radiograph was normal. Apart from an ESR of 100mm/1h, no remarkable findings resulted from the rest of the laboratory and imaging tests. Blood cultures were negative for bacteria and the virological control was also negative (RPR, EBV, CMV, TOXO, HIV, HBV, HCV, echo virus, coxsackie, parvo B19). Immunological tests (ANA, ANCA, RF, C3, C4, immunoglobulins) did not provide any abnormal findings.
In order to investigate the patient's fever, a chest CT scan was performed, which did not reveal significant findings in the lungs, apart from fibrous tissue in both apices (Fig. 1a and b) while an abdominal CT scan revealed a sacciform aneurysm of the abdominal aorta and soft tissue at the level of the left renal artery. No vertebral infection was detected and the differential diagnosis included mass, abscess and inflammatory lesion. The patient was then submitted to placement of intraluminal stent, during which no biopsy was performed.
Transesophageal echocardiography, fundoscopy, temporal artery biopsy and the thyroid gland biopsy were all normal. Moreover, a radioisotopic study performed with labeled autologous leukocytes did not detect any focus of abnormal concentration around the stent in the abdominal aorta, suggesting absence of inflammation in the area. Finally, the mantoux skin test was measured at 17mm. The patient received piperacillin/tazobactam and teicoplanin and then imipenem for a cumulative period of 20 days, and afterwards he was discharged from the hospital without being totally aferile.
One and a half months later he was readmitted suffering from fever up to 39  C for ten days and cough with mild expectoration. He showed signs of weakness and enfeeblement as well as mild confusion and disorientation in time and space. New chest X-ray and CT-scans were performed, the findings of which indicated miliary tuberculosis and presence of opacities in both upper lobes (Fig. 1c and d). A new abdominal CT scan revealed increased size of the soft tissue in 3.5 x 2.4 x 5 cm and expansion to the ipsilateral psoas muscle (Fig. 2a and b). The head CT scan was normal and the patient did not consent to lumbar puncture.
On the basis of the new imaging findings, tuberculosis was strongly suspected and the patient was transferred to the Pulmonary Department. The patient underwent bronchoscopy, but the Ziehl-Neelsen stain, the molecular test for M. tuberculosis of the bronchial lavage, as well as sputum and urine samples, were negative. However, 10 days later the liquid culture (Bactec Mgit) of bronchial lavage proved positive for M. tuberculosis and the patient was started on a 4-drug regimen with rifampicin, isoniazid, ethambutol and pyrazinamide.
A few days later a needle biopsy of the mass located behind the aortic aneurysm was performed under CT guidance. The biopsy showed no signs of granulation tissue. However, the molecular test for M. tuberculosis rRNA was in the gray zone and the Lowenstein-Jensen culture of the tissue block eventually proved positive. The strain was sensitive to all first-line anti-tuberculosis drugs.
The patient received anti-tuberculosis treatment for 9 months (2 months rifampicin - isoniazid - ethambutol - pyrazinamide & 7 months rifampicin - isoniazid) which he completed without experiencing any side effects. During treatment he showed an impressive improvement of his clinical condition. Fever remitted completely, he regained his body weight (about 10Kg in 9 months), became functional and fully oriented. The final ESR decreased to 35mm/1hr. A significant improvement in his chest and abdominal CT scans was also noted (Fig. 1, Fig. 2c and d).