Abdominal tuberculous lymphadenopathy: MR imaging findings

Tuberculosis of abdominal lymph nodes, peritoneum, and GI tract: a malignancy mimic

OBJECTIVE

The purpose is to discuss abdominal tuberculosis mimicking malignancy involving the lymph nodes, peritoneum, and the GI tract.

CONCLUSION

Awareness of the pathophysiology and imaging appearance on various modalities of abdominal tuberculosis involving the lymph nodes, peritoneum, and the GI tract that may simulate malignancy can aid differentiation, diagnosis, and therapy, particularly in areas where tuberculosis is endemic.

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.

Perihepatic lymphadenopathy in children with chronic viral hepatitis

Objective

To assess whether lymph node enlargement in the hepatoduodenal ligament occurs in children with chronic viral hepatitis B and C in comparison to healthy controls.

Subject and methods

In 49 patients with chronic viral hepatitis (38 with chronic hepatitis B, 11 with chronic hepatitis C, 31 male, 18 female; age range 1 to 17 years), and in 51 healthy controls (25 male, 26 female; age range 4 to 16 years), the total perihepatic lymph node volume was assessed using transabdominal ultrasonography as previously described in adult patients.

Results

Adequate visualization of the liver hilum was achieved in 46/49 (94%) pediatric patients with chronic viral hepatitis and in 46/51 (90%) pediatric healthy controls. In patients with adequate liver hilum visualization, enlarged perihepatic lymph nodes (longitudinal diameter >14 mm) were detected in 32/46 (70%) patients with chronic viral hepatitis and in 5/46 (11%) healthy controls. The total perihepatic lymph nodes volume [mean ± SD] was 1.0 ± 1.2 mL (0.1–5.4 mL) in patients with chronic viral hepatitis and 0.1 ± 0.1 mL (0.0–0.4 mL) in healthy controls (p < 0.05). A maximal lymph node diameter >14 mm identified patients with chronic viral hepatitis with 70% sensitivity and 89% specificity.

Conclusion

Transabdominal ultrasound can detect lymph nodes within the hepatoduodenal ligament not only in adults but also in children. Paediatric patients with chronic viral hepatitis have significantly enlarged perihepatic lymph nodes compared to controls. Therefore, sonographic assessment of perihepatic lymphadenopathy might be a non-invasive diagnostic tool to screen paediatric patients for chronic viral hepatitis.

Differentiation between tuberculosis and leukemia in abdominal and pelvic lymph nodes: evaluation with contrast-enhanced multidetector computed tomography

PURPOSE

To compare the characteristics of tubercular vs. leukemic involvement of abdominopelvic lymph nodes using multidetector computed tomography (CT).

MATERIALS AND METHODS

We retrospectively reviewed multidetector computed tomography features including lymph node size, shape, enhancement patterns, and anatomical distribution, in 106 consecutive patients with newly diagnosed, untreated tuberculosis (55 patients; 52%) or leukemia (51 patients; 48%). In patients with leukemia, 32 (62.7%) had chronic lymphocytic leukemia, and 19 (37.3%) had acute leukemias; of these, 10 (19.6%) had acute myeloid leukemia, and 9 (17.6%) had acute lymphocytic leukemia.

RESULTS

The lower para-aortic (30.9% for tuberculosis, 63.2% for acute leukemias and 87.5% for chronic lymphocytic leukemia) and inguinal (9.1% for tuberculosis, 57.9% for acute leukemias and 53.1% for chronic lymphocytic leukemia) lymph nodes were involved more frequently in the three types of leukemia than in tuberculosis (both with p <0.017). Tuberculosis showed peripheral enhancement, frequently with a multilocular appearance, in 43 (78.2%) patients, whereas patients with leukemia (78.9% for acute myeloid leukemia and acute lymphocytic leukemia, 87.5% for chronic lymphocytic leukemia) demonstrated predominantly homogeneous enhancement (both with p <0.017). For the diagnosis of tuberculosis, the analysis showed that a peripheral enhancement pattern had a sensitivity of 78.2%, a specificity of 100%, and an accuracy of 88.7%. For the diagnosis of leukemia, the analysis showed that a homogeneous enhancement pattern was associated with a sensitivity of 84.3%, a specificity of 94.5%, and an accuracy of 89.6%.

CONCLUSION

Our findings indicate that the anatomical distribution and enhancement patterns of lymphadenopathy seen on multidetector computed tomography are useful for differentiating between untreated tuberculosis and leukemia of the abdominopelvic lymph nodes.

Abdominal tuberculosis with periportal lymph node involvement mimicking pancreatic malignancy in an immunocompetent adolescent

Abdominal tuberculosis manifesting as isolated lymphadenopathy is rare, particularly in children. Tuberculous involvement of the pancreatic head and peripancreatic area can simulate a neoplasm of the pancreatic head. To our knowledge, obstructive jaundice caused by tuberculous lymphadenopathy has not been reported in children or adolescents. Here we present radiologic findings in a case of tuberculous lymphadenopathy that mimicked malignancy of the pancreatic head and caused obstructive jaundice in an immunocompetent adolescent.

Tuberculosis versus lymphoma in the abdominal lymph nodes: a comparative study using contrast-enhanced MRI

PURPOSE

The purpose of this study was to determine the differential characteristics on MRI between tuberculosis and lymphoma in abdominal lymph nodes.

MATERIALS AND METHODS

We conducted a retrospective analysis for the counter, size, signal intensity, enhancement patterns, and anatomic distribution of lymph nodes in 57 consecutive patients with documented tuberculosis (28 patients; 49.1%) and newly diagnosed, untreated lymphoma (29 patients; 50.9%).

RESULTS

Twenty-four cases (85.7%) in the tuberculosis group were hyperintense on T2-weighted images and either hypointense or isointense on T1-weighted images with respect to the abdominal wall muscle. All cases in the lymphoma group were hyperintense on T2-weighted images and isointense on T1-weighted images with respect to the abdominal wall muscle. Concerning the main anatomic distribution of lymph nodes, the lymph nodes in the lower paraaortic region were more frequently involved in the lymphoma group (48.3%) than in tuberculosis (17.9%, p<0.05). Moreover, mesenteric lymph nodes were more often involved in tuberculosis (32.1%) than in lymphoma (6.9%, p<0.05). Tuberculous lymphadenopathy showed predominantly peripheral enhancement, frequently with a multilocular appearance; whereas lymphomatous adenopathy often demonstrated uniform homogeneous enhancement (all p<0.001).

CONCLUSION

Contrast-enhanced MRI can be useful in differentiation between these two entities.

Neoplasm-like abdominal nonhematogenous disseminated tuberculous lymphadenopathy: CT evaluation of 12 cases and literature review

AIM: To assess the diagnostic value of computed tomography (CT) imaging in screening for abdominal nonhematogenous disseminated tuberculous lymphadenopathy (TL).

METHODS: The CT scans of 12 patients with abdominal nonhematogenous disseminated TL suggestive of neoplasm were retrospectively analyzed in this review. The final diagnoses were confirmed by lymph node pathology for seven patients and by laparoscopic surgery for five patients. All of the patients were treated at our institution between April 1995 and August 2009.

RESULTS: The sites of involvement were the periportal (n = 6), peripancreatic (n = 3), periaortic (n = 3), and mesenteric (n = 2) regions. On the plain CT scan, the lymphadenopathy showed a heterogeneous isodensity or hypodensity in 11 patients and a low density in one patient. Peripheral enhancement was observed on the dynamic contrast-enhanced CT scans for all patients. In two cases, scans were more revealing during the portal venous and delayed phases.

CONCLUSION: Abdominal lymphadenopathy with predominant peripheral rim-like enhancement on the dynamic contrast-enhanced CT scan may suggest a diagnosis of TL.

Isolated periportal tuberculosis: characteristic findings of clinical imaging

Isolated periportal tuberculous lymphadenopathy is a rare clinical entity. This report describes a 56-year-old woman with the disease, who showed characteristic findings on clinical imaging studies. Computed tomography showed a low-density mass with peripheral enhancement and calcification, adjacent to the pancreatic head and caudate lobe of the liver. 2-[Fluorine 18]fluoro-2-deoxy-D-glucose positron emission tomography imaging co-registered with computed tomography showed slightly increased uptake along the periphery of the lesion. The diagnosis was confirmed at laparotomy. The manifestation of the disease is nonspecific, and preoperative differential diagnosis from neoplastic disease is often difficult. Its clinical and radiological features are briefly reviewed.

Review article: the diagnosis and management of Crohn's disease in populations with high-risk rates for tuberculosis

BACKGROUND

Distinguishing Crohn's disease from intestinal tuberculosis in endemic areas is challenging as both conditions have overlapping clinical, radiological, endoscopic and histological characteristics. Furthermore, high rates of latent tuberculosis confer a considerable risk of reactivation once therapy for established Crohn's disease is started.

AIM

To review current strategies in differentiating these two conditions, and in managing Crohn's disease, in populations with high rates of tuberculosis.

METHODS

Literature review and clinical experience.

RESULTS

While various clinical, radiological, endoscopic and histological parameters may aid in differentiating Crohn's disease from intestinal tuberculosis, these remain imperfect and as treatment options differ misdiagnosis has grave consequences. We propose a diagnostic algorithm, based on currently available evidence and experience, to aid in this dilemma. We also discuss approaches to the management of Crohn's disease, including agents targeting tumour necrosis factor-alpha, in patients at risk of developing tuberculosis.

CONCLUSIONS

A diagnosis of Crohn's disease in individuals at risk for tuberculosis should only be made after careful interpretation of clinical signs, abdominal imaging and systematic endoscopic and histological assessment. Newer techniques for the diagnosis of latent tuberculosis still need to be validated in this environment, and guidelines on the treatment of latent tuberculosis in this setting require clarification.

[Imaging of pancreatic and hepatic tuberculosis in an infant presenting with jaundice]

The incidence of abdominal tuberculosis has increased over the last decade and can mimic any other disease. Pancreatic involvement is an uncommon cause of jaundice in children. A case of obstructive jaundice due to pancreatic tuberculosis in an infant, with hepatic involvement is reported. The sonographic and computed-tomographic features are described.

La tuberculose hépato-splénique chez l’enfant

Isolated tuberculous involvement of the liver and spleen is infrequent. We report such a case in a child. The differential diagnosis of isolated multi-nodular diseases of the liver and spleen is reviewed.

Vascular involvement secondary to tuberculosis of the abdomen

Although involvement of the abdomen is a common site of extrapulmonary tuberculosis, involvement of abdominal vessels with complications is rare after infections with Mycobacterium tuberculosis (M. tuberculosis). Vascular complications may result from direct involvement by M. tuberculosis of the vascular wall or may occur as a consequence of local spreading from a tuberculous mass. We describe the imaging findings in two patients with proven tuberculosis of the abdomen and significant vascular complications. In one patient, "dry plastic" peritonitis and tuberculous lymphadenopathy at the level of the porta hepatis with subsequent encasement and compression of the portal vein resulted in prestenotic dilatation and varicose formation in the upper abdomen. In the other patient, bulky necrotic tuberculous lymphadenopathy, located at the splenic hilum, resulted in encasement with stenosis of the splenic vessels and subsequent splenic infarction.

Abdominal tuberculous lymphadenopathy: MRI features

The aim of this study was to describe the MRI features of abdominal tuberculous lymphadenopathy. MRI studies of 13 patients with abdominal tuberculous lymphadenopathy were reviewed with regard to anatomic distribution and size. Signal intensities, in relation to abdominal wall muscle, on unenhanced T1- and T2-weighted images and patterns of contrast enhancement of lymphadenopathy were evaluated in each patient. In each patient, the largest lymph node with the same imaging characteristic was evaluated. The upper paraaortic region was the most common site of involvement (n=12 patients), followed by the lesser omentum (n=10 patients), the anterior pararenal space (n=9 patients), the lower paraaortic area (n=8 patients), the small bowel mesentery (n=6 patients), the greater omentum (n=2 patients) and the originating site of the inferior mesenteric artery (n=2 patients). The mean lymph node size was 1.8 cm (range 0.5-5 cm). The overall mean lymph node number per patient was 16 (range 2-50). A total of 41 lymph nodes were evaluated in 13 patients. On T2-weighted images, 40 lesions were hyperintense and one lesion was isointense. Nine hyperintense lesions showed a hypointense peripheral rim and seven internal heterogeneïty. Perinodal T2-hyperintensity was present in 23 lesions. The latter finding was valid for all patients. On T1-weighted images, 30 lesions were hypointense and 11 isointense. Nine hypointense lesions demonstrated a hyperintense peripheral rim, and six were heterogeneous. Contrast-enhanced fat-suppressed T1-weighted images demonstrated predominant peripheral enhancement in 28 lesions: (1) peripheral uniform, thin (n=19); (2) thick irregular, complete (n=3); and (3) conglomerate group of nodes showing peripheral and central areas of rim enhancement (n=6). Heterogeneous and homogeneous enhancement was present in ten and three lesions, respectively. Combinations of enhancing patterns in the same nodal group and different nodal groups were seen in eight and nine patients, respectively. Abdominal tuberculous lymphadenopathy may show a variety of signal intensities and patterns of contrast enhancement on MRI. Lymphadenopathy, hypointense on T1-weighted, hyperintense on T2-weighted images with perinodal hyperintensity, and predominant peripheral rimlike enhancement may suggest the diagnosis of tuberculosis.

Abdominal lymphadenopathy in beta-thalassemia: MRI features and correlation with liver iron overload and posttransfusion chronic hepatitis C

OBJECTIVE

The objective of our study was to describe the MRI features of abdominal lymphadenopathy in patients with beta-thalassemia major and investigate the relation of abdominal lymphadenopathy with the severity of iron overload and posttransfusion chronic hepatitis C.

MATERIALS AND METHODS

Abdominal MRI studies of 60 consecutive patients with beta-thalassemia major, performed for quantification of liver iron overload at a single institution, were retrospectively studied for the presence of lymph nodes and their distribution, size, and number. The signal intensity ratios of liver, spleen, and the largest lymph node to the right paraspinous muscle (L/M, S/M, and LN/M, respectively) were calculated on T1-weighted gradient-echo images. MRI findings for the lymph nodes were compared with the histologically assigned activity level of chronic hepatitis C that was available in 17 patients who had undergone liver biopsy within 1 month of the MRI examination.

RESULTS

Hypointense abdominal lymph nodes larger than 7 mm were seen in 19 (32%) of 60 thalassemic patients in perihepatic and paraortic distributions. Lymphadenopathy was related to both the severity of hepatic siderosis, as expressed by the L/M values, and the presence of chronic hepatitis C, given that 18 (95%) of the 19 thalassemic patients with lymphadenopathy had chronic hepatitis C. Moreover, thalassemic patients with a moderate or severe level of hepatic inflammation presented with abdominal lymphadenopathy more frequently than those with mild hepatic inflammation.

CONCLUSION

The development of hypointense abdominal lymphadenopathy in patients with beta-thalassemia major who have received multiple transfusions depends both on the severity of liver iron overload and on the presence and the activity level of coexistent chronic hepatitis C.

Pancreatic Castleman's disease: MR findings

Castleman's disease can involve a number of organs/tissues but generally affects the mediastinum. Occurrence of Castleman's disease in the pancreas in either form of the disease, the hyaline vascular or the plasma-cell type, is very rare, with only a few case reports in which the imaging findings were described. The MR imaging of pancreatic Castleman's disease has not been previously reported, to our knowledge. We submit the MRI findings in a patient with the plasma-cell-type of Castleman's disease, which presented as an isolated smoothly marginated pancreatic mass, hypointense on T1-weighted fat-suppressed images, isointense on T2-weighted sequences, and that after contrast material injection showed peripheral rim enhancement during the arterial phase.

Chronic hepatitis C activity: correlation with lymphadenopathy on MR imaging

OBJECTIVE

To study the MR appearance of lymph nodes in relation to activity of chronic active hepatitis C, we correlated the findings on MR imaging with a histologic grading of the activity level.

MATERIALS AND METHODS

Fifty patients with chronic active hepatitis C, who had MR imaging examinations and a related histology report from a liver biopsy obtained within 1 month of the MR imaging were chosen from our radiology database and studied retrospectively. All patients were examined over a 4-year period at a single institution to detect cirrhosis or hepatocellular carcinoma. We divided the 50 patients into the mild, moderate, or severe activity groups, according to their histology reports. Two radiologists, unaware of the histologic classifications, individually reviewed the MR images to observe the perihepatic locations, number, size (defined as the sum of the length-by-width products of the largest three nodes), and intensity of the lymph nodes relative to the spleen. The clinical records of the patients were reviewed to check the results of their liver function tests. The lymph node findings on MR imaging were compared with the histologically confirmed activity level of chronic hepatitis C.

RESULTS

Forty-four (88.0%) of 50 patients had perihepatic lymph nodes larger than 5 mm on MR images, including 64.2% (9/14) of the patients with mild activity, 96.3% (26/27) of the patients with moderate activity, and 100% (9/9) of the patients with severe activity (p = 0.0034). The average number +/- the standard deviation (SD) of perihepatic lymph nodes was 2.5 +/- 1.8 in patients with mild activity, 5.6 +/- 2.2 in patients with moderate activity, and 8.3 +/- 3.5 in patients with severe activity (p = 0.0001). The average size (+/- SD) of the lymph nodes was 151.0 +/- 104.9 mm(2) in the mild activity group, 366.8 +/- 143.0 mm(2) in the moderate activity group, and 488.2 +/- 244.8 mm(2) in the severe activity group (p = 0.0001). On fat-saturated fast spin-echo T2-weighted MR images, the average number (+/- SD) of hyperintense nodes was 0.17 +/- 0.25 in the mild activity group, 1.7 +/- 0.80 in the moderate activity group, and 2.4 +/- 0.60 nodes in the severe activity group (p = 0.0001). No relationship between histologic activity and results from liver function tests was found.

CONCLUSION

MR imaging depicts perihepatic lymph nodes in most patients with chronic hepatitis C. Lymph node number, size, and hyperintensity were related to the activity of chronic hepatitis C, but the results of liver function tests were not.