Tuberculosis in the abdominal lymph nodes: evaluation with contrast-enhanced magnetic resonance imaging

Coeliac lymph node abscess: A case report of a rare manifestation of extrapulmonary tuberculosis

Tuberculosis is a leading cause of death worldwide, especially in developing countries. It can affect any site in the body and have a myriad of presentations making diagnosis challenging. Tuberculous lymphadenitis in the abdomen is rare. We present a case of a 42-year-old man who presented with non-specific abdominal symptoms and was found to have an intraabdominal abscess on computed tomography scan of the abdomen. Endoscopic ultrasound-guided aspiration was performed, and tuberculosis was confirmed. This case highlights the importance of having a high clinical suspicion of tuberculosis even with vague symptoms in tuberculosis endemic countries. This would prevent unnecessary surgery as tuberculosis is responsive to anti-tuberculosis drugs.

Diffusion-weighted magnetic resonance imaging of abdominal tuberculosis: a new take on an old disease

Abdominal tuberculosis is a major cause of mortality and morbidity in developing countries also re-emerging in western world due to the AIDS epidemic and population migration. Large proportion of the patients are young and hence radiation exposure is of concern. In addition, in some patients, contrast may be contraindicated or repeat studies may be required, where MR especially DWI may be useful. The aim of the study is to describe MRI features in abdominal tuberculosis including DWI in the involved bowel, lymphadenopathy, omental, and peritoneal thickening. Nodes being especially easy to appreciate on DWI, thus DWI in conjunction with routine noncontrast MR sequence can be useful technique to identify abdominal tubercular lesions in patients with contraindication to contrast.

Comparison of Silicosis and Tuberculosis Involving Mediastinal Lymph Nodes Based on Contrast-Enhanced Multidetector-Row Computed Tomography

PURPOSE

To investigate the different imaging features of contrast-enhanced multidetector-row-computed tomography (MDCT) for distinguishing between silicosis and tuberculosis involving the mediastinal lymph nodes.

METHODS

86 silicosis patients and 61 tuberculosis patients with mediastinal lymphadenopathy based on contrast-enhanced MDCT were included. The enhanced patterns, anatomical distribution and calcification features of the enlarged lymph nodes were retrospectively compared between the groups using the Pearson chi-square test or Fisher's exact test.

RESULTS

Homogeneous enhancement of the mediastinal lymph nodes was more commonly observed in silicosis (94.2%, 81/86) than in tuberculosis (19.7%, 12/61). Peripheral enhancement was more frequent in tuberculosis (n = 44, 72.1%) than in silicosis involving the mediastinal lymph nodes (n = 1, 1.2%), and multilocular appearance was more frequent in TB than in silicosis. Tuberculosis was more likely to affect regions 1R, 2R, 2L, 3A, 5 and 6 than silicosis (all p < 0.05), especially region 2R. Calcification of the lymph nodes was more common in the silicosis group than in tuberculosis group. The sensitivity, specificity, and accuracy of silicosis with lymphadenopathy with homogeneous enhanced pattern were 94.2%, 80.3% and 88.4%, respectively. The sensitivity, specificity, and accuracy of tuberculosis lymphadenopathy with peripheral enhanced pattern were 72.1%, 98.8%, and 87.7%, respectively.

CONCLUSION

The predominant enhanced patterns, anatomical distribution, and calcification features of mediastinal lymph nodes were different between tuberculosis and silicosis. These radiographic features might help differentiate tuberculosis from silicosis, which provides imaging information for the differential diagnosis of the two diseases in a clinical setting.

Value of apparent diffusion coefficient for differentiating peripancreatic tuberculous lymphadenopathy from metastatic lymphadenopathy

PURPOSE

To evaluate effectiveness of the apparent diffusion coefficient (ADC) values of the peripancreatic lymphadenopathy to differentiate tuberculous lymphadenopathy from metastatic lymphadenopathy.

MATERIALS AND METHODS

Twenty-nine patients with 65 peripancreatic necrotic tuberculous lymphadenopathy and 31 patients with 47 peripancreatic necrotic metastatic lymphadenopathy from pancreatic ductal adenocarcinoma, who underwent magnetic resonance imaging (MRI), were included in this study. MRI features in the T1-weighted image (WI), T2WI, and diffusion-weighted image were analyzed. The ADC values of necrotic and non-necrotic portions of the lymph nodes were measured and compared using t test. Receiver operating characteristic analysis was performed to obtain the optimal ADC threshold value and diagnostic accuracy for differentiating tuberculous lymphadenopathy from metastatic lymphadenopathy.

RESULTS

On T2WI, the signal intensity of necrotic portions was variable in tuberculous lymphadenopathy, but was mostly high in metastatic lymphadenopathy. The mean ADCs of necrotic portions of tuberculous lymphadenopathy were significantly lower than those of metastatic lymphadenopathy ([0.919 ± 0.272] × 10^-3 mm²/s vs. [1.553 ± 0.406] × 10^-3 mm²/s, p < 0.001). Receiver operating characteristic analysis for differentiating tuberculous from metastatic lymphadenopathy demonstrated an area under the curve for the ADC values of necrotic portions of 0.929 (95% CI, 0.865-0.969) with an ADC threshold of 1.022. The sensitivity and specificity for the differentiation of tuberculous from metastatic lymphadenopathy were 80.0% and 97.8%, respectively.

CONCLUSION

The ADC values of necrotic portions of peripancreatic lymphadenopathy may be useful for differentiating tuberculous from metastatic lymphadenopathy.

Intestinal tuberculosis: a diagnostic challenge

OBJECTIVE

To describe characteristics, presentation, time to diagnosis and diagnostic findings of patients with intestinal tuberculosis (ITB) in a low-burden country.

METHOD

Retrospective study of 61 consecutive ITB patients diagnosed between 2008 and 2014 at a large East London hospital.

RESULTS

Forty of sixty-one patients were male. Mean age was 34.6 years. 93% of patients were born abroad, mostly from TB-endemic areas (Indian subcontinent: 88%, Africa: 9%). 25% had concomitant pulmonary TB. Median time from symptom onset to ITB diagnosis was 13 weeks (IQR 3-26 weeks). Ten patients were initially treated for IBD, although patients had ITB. The main sites of ITB involvement were the ileocaecum (44%) or small bowel (34%). Five patients had isolated perianal disease. Colonoscopy confirmed a diagnosis of ITB in 77% of those performed. 42 of 61 patients had a diagnosis of ITB confirmed on positive histology and/or microbiology.

CONCLUSION

Diagnosis of ITB is often delayed, which may result in significant morbidity. ITB should be excluded in patients with abdominal complaints who come from TB-endemic areas to establish prompt diagnosis and treatment. Diagnosis is challenging but aided by axial imaging, colonoscopy and tissue biopsy for TB culture and histology.