Imaging of tuberculosis. II. Abdominal manifestations in 112 patients

Computed tomographic features of abdominal tuberculosis: unmask the impersonator!

PURPOSE

Abdominal tuberculosis (ATB) mimics various infectious, inflammatory, and neoplastic conditions and hence requires a high index of suspicion for accurate diagnosis, especially in low prevalence areas. It is difficult to consistently establish a histopathological diagnosis of ATB which underlines the importance of supportive evidences for institution of prompt empirical therapy to prevent associated morbidity and mortality.

METHODS

We retrospectively evaluated clinical and imaging features of 105 ATB cases and classified their CT findings based on peritoneal, lymph node, bowel, and solid organ involvement. Concomitant pulmonary and extra-pulmonary involvement was assessed.

RESULTS

Abdominal pain (78.1%) followed by fever (42.9%) were the commonest presenting symptoms. Peritoneal TB (77.14%) most commonly presented with a mix of ascites (49.38%), peritoneal (28.40%), and omental involvement (27.16%). Lymphadenopathy (57.1%) most commonly presented as necrotic nodes (81.67%) at mesenteric, peripancreatic, periportal, and upper paraaortic regions. Commonest site of bowel involvement (cumulative of 62.85%) was ileocecal region, with the commonest pattern of involvement being circumferential bowel wall thickening without bowel stratification with mild luminal narrowing. Hepatic (13.33%) and splenic (16.2%) involvement predominantly presented as multiple microabscesses. Adrenal and pancreatic involvement was noted in 4.7% and 1.9% of patients, respectively. 38.1% patients showed concomitant pulmonary and extra-pulmonary TB.

CONCLUSION

ATB has varied radiological features; however, peritoneal involvement in the form of mild ascites, smooth peritoneal thickening, smudgy omentum, multi-focal bowel involvement, necrotic nodes, and multiple visceral microabscesses point towards a diagnosis of ATB in appropriate clinical setting.

Tuberculosis of the Liver, Biliary Tract, and Pancreas

Tuberculosis of the liver, biliary tract, and pancreas is discussed. In addition, tuberculosis in the setting of HIV-AIDS and liver transplantation is explored. Drug-induced liver injury secondary to antituberculosis medication and monitoring and prophylactic treatment for such injury is also considered.

Role of routine abdominal ultrasonography in intensified tuberculosis case finding algorithms at HIV clinics in high TB burden settings

Background

High proportion of TB in people living with HIV (PLHIV) is undiagnosed. Due to this active TB case finding is recommended for HIV clinics in high TB burden countries. Presently sputum examination and chest radiography are frontline tests recommended for HIV infected TB presumptives. Abdominal TB which occurs frequently in PLHIV may be missed even by existing programmatic intensified case finding protocols. This study evaluated the routine use of ultrasonography (USG) for active case finding of abdominal TB in HIV clinics.

Methods

Retrospective analysis of eight years’ data from an HIV Clinic in a TB hospital in India. Patients underwent chest x-ray, sputum examination, USG abdomen and routine blood tests at entry to HIV care. Case forms were scrutinized for diagnosis of TB, USG findings and CD4 cell counts. Abdominal TB was classified as probable or possible TB. Probable TB was based on presence of two major USG (abdomen) findings suggestive of active TB, or one major USG finding with at least two minor USG findings or at least two symptoms, or any USG finding with microbiologically confirmed active TB at another site. Possible TB was based on the presence of one major USG finding, or the presence of two minor USG findings with at least two symptoms. Bacteriological confirmation was not obtained.

Results

Eight hundred and eighty-nine people PLHIV underwent a baseline USG abdomen. One hundred and thirteen of 340 cases already diagnosed with TB and 87 of the 91 newly diagnosed with TB at time of HIV clinic registration had abdominal TB. Non-abdominal symptoms like weight loss, fever and cough were seen in 53% and 22% cases had no symptoms at all. Enlarged abdominal lymph nodes with central caseation, ascitis, splenic microabsesses, bowel thickening and hepatosplenomegaly were the USG findings in these cases.

Conclusions

Abdominal TB is a frequent TB site in PLHIV presenting with non-abdominal symptoms. It can be easily detected on basis of features seen on a simple abdominal ultrasound. Abdominal USG should be essential part of intensified TB case finding algorithms for HIV infected people living in high TB burden settings.

Accuracy of computed tomographic features in differentiating intestinal tuberculosis from Crohn's disease: a systematic review with meta-analysis

Abdominal computed tomography (CT) can noninvasively image the entire gastrointestinal tract and assess extraintestinal features that are important in differentiating Crohn's disease (CD) and intestinal tuberculosis (ITB). The present meta-analysis pooled the results of all studies on the role of CT abdomen in differentiating between CD and ITB. We searched PubMed and Embase for all publications in English that analyzed the features differentiating between CD and ITB on abdominal CT. The features included comb sign, necrotic lymph nodes, asymmetric bowel wall thickening, skip lesions, fibrofatty proliferation, mural stratification, ileocaecal area, long segment, and left colonic involvements. Sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (DOR) were calculated for all the features. Symmetric receiver operating characteristic curve was plotted for features present in >3 studies. Heterogeneity and publication bias was assessed and sensitivity analysis was performed by excluding studies that compared features on conventional abdominal CT instead of CT enterography (CTE). We included 6 studies (4 CTE, 1 conventional abdominal CT, and 1 CTE+conventional abdominal CT) involving 417 and 195 patients with CD and ITB, respectively. Necrotic lymph nodes had the highest diagnostic accuracy (sensitivity, 23%; specificity, 100%; DOR, 30.2) for ITB diagnosis, and comb sign (sensitivity, 82%; specificity, 81%; DOR, 21.5) followed by skip lesions (sensitivity, 86%; specificity, 74%; DOR, 16.5) had the highest diagnostic accuracy for CD diagnosis. On sensitivity analysis, the diagnostic accuracy of other features excluding asymmetric bowel wall thickening remained similar. Necrotic lymph nodes and comb sign on abdominal CT had the best diagnostic accuracy in differentiating CD and ITB.

Capsule endoscopy in small bowel Crohn’s disease and Tuberculosis

Differentiation of small bowel tuberculosis (SBTB) from Crohn’s disease (CD) is a diagnostic challenge. We studied 52 patients with suspected SBTB or CD with terminal ileal involvement, who were prospectively enrolled. After confirming patency of the gastrointestinal tract, 26 patients underwent capsule endoscopy (CE). A final diagnosis of CD was found in 18 patients and SBTB in eight patients. All SBTB patients had involvment of the ileocecal valve (ICV) with large (n = 6) and aphthous (n = 2) ulcers in the ileal segment. In CD, ICV involvement was seen in five (33%) patients. Large and aphthous ulcers were observed in seven (47%) and 15 (100%) patients, respectively. On comparison with CD, patients with SBTB had increased frequency of ICV involvement ( P = 0.002) and lesser frequency of aphthous ulcers ( P = 0.007). CE can help in differentiating CD from SBTB by the position of its involvement and the type of ulcers present.

Intestinal tuberculosis versus crohn's disease: Clinical and radiological recommendations

Intestinal tuberculosis is a common clinical problem in India. The clinical features of this disease are nonspecific and can be very similar to Crohn's disease. Radiological evaluation of the small bowel has undergone a paradigm shift in the last decade. This long tubular organ that has traditionally been difficult to evaluate can now be well-visualized by some innovative imaging and endoscopic techniques. This article highlights the state-of-the-art evaluation of ulceroconstrictive diseases of the bowel and provides recommendations for the differentiation of intestinal tuberculosis from Crohn's disease.

Evaluation of intestinal tuberculosis by multi-slice computed tomography enterography

BACKGROUND

Multi-slice computed tomography enterography (MSCTE) is now widely used to diagnose and monitor intestinal disease. Preliminary studies suggest that MSCTE may be useful in detecting intestinal tuberculosis (ITB). We sought to assess the use of MSCTE for the diagnosis of ITB in our medical center.

METHODS

In this retrospective study, 15 patients (11 males and 4 females, 6 to 65 years old) were enrolled and diagnosed with ITB by MSCTE. Diagnosis were confirmed by pathology or clinical criteria. Two experienced abdominal radiologists evaluated the images and defined the location, number, shape, edge, surrounding tissue alterations of ITB and other associated changes in the peritoneum, mesentery and solid abdominal organs.

RESULTS

The interval between the onset of symptoms and diagnosis varied from 20 days to 10 years. The most common symptom was abdominal pain (80 %). The ileocecum was the most common site affected by ITB (87 %). Morphological MSCTE findings were variable and included multi-segmental symmetric intestinal mural thickening found in 6 patients (40 %), solid masses found in 9 patients (60 %), and enlarged lymph nodes (LNs) found in 13 (87 %) patients. Non-enhancing central necrosis and rim enhancement were noted in 10 patients (67 %).

CONCLUSIONS

Characteristic MSCTE findings of ITB include solid mass or multi-segmental symmetric mural thickening involving the ileocecal area and rim enhanced LNs. Knowledge of these features in combination with a high index of suspicion can be useful in early diagnosis of ITB.

Tuberculous peritonitis

Tuberculous peritonitis is a serious condition with rising prevalence in recent years. It is especially common in those patients with risk factors such as an immunocompromised state, chronic kidney disease, or cirrhosis/liver disease. Spread is typically hematogenous from pulmonary foci. We report on a 34-year-old man who presented with initial complaints of cough, low-grade fevers, abdominal pain, and nausea/vomiting. Chest x-ray showed a cluster of nodular opacities on the right upper lobe, and a CT scan showed diffuse thickening and nodularity of the omentum with prominent mesenteric lymph nodes, consistent with tuberculous peritonitis.

Mapping the epidemiology and trends of extra-pulmonary tuberculosis in Saudi Arabia

An extra-pulmonary tuberculosis (EPTB) infection rate of 30% in Saudi Arabia remains above the global rate. A variable rate of infection in each province has been reported and the involvement of most organs has been cited. Nationwide collective data on the current trends of infection are scarce and the factors behind the increased rate of EPTB are perplexing. This review endeavors to shed light into the epidemiology of EPTB, various types of infections sites, geographical differences in the infection rate, known risk factors, and challenges in the diagnosis and management of EPTB in Saudi Arabia.

Splenic tuberculosis presenting as fever of unknown origin with severe neutropenia

Fever of undetermined origin always poses a challenging problem to the physician. Tuberculosis is an important health problem in developing countries. It is mostly seen in immune-compromised patients. And it is one of the common causes of fever of unknown origin. I am reporting a case of a splenic tuberculosis in 48 years old male who is not known of any immune deficiency state, he was presented with 3 weeks history of fever and found to have severe neutropenia and with negative work up for all hematological, rheumatological and malignant causes. A computerized tomography scan of the abdomen confirmed splenic enlargement with multiples hypo dense lesions consist with either splenic infection or splenic lymphoma so exploratory splenectomy was performed. Histological examination revealed granulomatouse inflammation with numerous acid fast bacilli consist with tuberculosis. He was started on four anti-tuberculouse drugs. in less than one week his fever subside with normalization of his neutrophilic count

Differentiation of Crohn’s disease from intestinal tuberculosis in India in 2010

Differentiating intestinal tuberculosis from Crohn’s disease (CD) is an important clinical challenge of considerable therapeutic significance. The problem is of greatest magnitude in countries where tuberculosis continues to be highly prevalent, and where the incidence of CD is increasing. The final clinical diagnosis is based on a combination of the clinical history with endoscopic studies, culture and polymerase chain reaction for Mycobacterium tuberculosis, biopsy pathology, radiological investigations and response to therapy. In a subset of patients, surgery is required and intraoperative findings with pathological study of the resected bowel provide a definitive diagnosis. Awareness of the parameters useful in distinguishing these two disorders in each of the different diagnostic modalities is crucial to accurate decision making. Newer techniques, such as capsule endoscopy, small bowel enteroscopy and immunological assays for Mycobacterium tuberculosis, have a role to play in the differentiation of intestinal tuberculosis and CD. This review presents currently available evidence regarding the usefulness and limitations of all these different modalities available for the evaluation of these two disorders.

Pancreatic tuberculosis: a clinical and imaging review of 32 cases

BACKGROUND

Tuberculosis of the pancreas is a rare entity, and anecdotal reports describing imaging features of pancreatic tuberculosis have been described in medical literature. The imaging features including computed tomography (CT) and ultrasonography in diagnosed cases of tubercular involvement of the pancreas are described, with an overview of clinical features and laboratory investigations.

MATERIALS AND METHODS

We analyzed records of 384 patients of diagnosed cases of abdominal tuberculosis for involvement of pancreas and detected 32 patients (8.33%) who had pancreatic involvement. This included 22 men and 10 women with an age range of 19 to 64 years (mean age of 42.5 years), who were detected to have pancreatic tuberculosis from 1999 to 2004 in our institute. We reviewed the clinical, radiologic (ultrasonographic and CT features), and laboratory findings of all patients. The criteria for diagnosis of tuberculosis were based on ascitic fluid adenosine deaminase level in 14 patients, fine-needle aspiration cytology of lymph nodes in 9 patients, and presence of pulmonary tuberculosis on chest radiograph, which was found in 9 patients. On follow-up, 6 months after antituberculous treatment, 25 patients showed response to anti-Koch's treatment, 3 patients had drug-resistant tuberculosis, 2 patients died, and 2 patients were lost to follow-up.

RESULTS

The male/female ratio was 2.2:1. The maximum number of patients was in the fourth decade (30-39 years). The duration of symptoms was spanning between 2 and 11 months, with a mean duration of 6 months. The most common symptom was abdominal pain localized to the epigastrium. Sixteen patients were seropositive for HIV-1 infection. Fourteen patients had history of tuberculosis of the lungs, whereas 18 patients had pancreatic and peripancreatic involvement as the primary manifestation. Ultrasonography showed bulky inhomogenous pancreas in 5 patients; solitary or multiple hypoechoic collections were observed in all 7 and 20 patients, respectively. CT findings demonstrated hypodense collections within the pancreas associated with peripancreatic lymphadenopathy in 29 patients. Three patients had a complex pancreatic mass lesion.

CONCLUSIONS

Pancreatic tuberculosis can present with a variable spectrum of imaging findings. Tuberculosis of the pancreas should be considered as a diagnostic possibility in patients who present with a pancreatic space occupying lesion associated with peripancreatic lymphadenopathy.

Clinical review of 23 patients with tuberculous peritonitis: presenting features and diagnosis

OBJECTIVE

To better identify which clinical, laboratory, radiological and invasive procedures were most useful in diagnosing tuberculous peritonitis and to assess the methods in order to reach the diagnosis in future cases.

METHODS

Tuberculous peritonitis cases diagnosed between 2000 and 2006 were reviewed retrospectively. Their clinical presentation, physical examination, laboratory and diagnostic methods were evaluated.

RESULTS

Twenty-three cases oftuberculous peritonitis were diagnosed. The mean age of the patients were 30 +/- 11 years and 16 were women. The mean duration of symptoms prior to diagnosis was 3.6 months. All patients presented with abdominal pain. Abdominal swelling (91.3%), loss of appetite (87%) and weight loss (82.6%) were the other commonest symptoms. The major physical findings were ascites (78.3%) and fever (60.9%). The serum ascites albumin gradient was < 1.1 g/dL in all. An ascites fast bacilli smear was positive in 12 (52.2%) patients. Skin tests with purified protein derivative, adenosine deaminase and polymerase chain reaction were performed in seven, four and five patients, respectively. The tuberculous culture was positive in only two. The most common radiological findings were ascites (100%) and omental involvement (65.2%). A laparoscopy was performed in nine of 23 patients. A total of 22 patients completed anti-tuberculous therapy successfully and were cured, except one with cirrhosis.

CONCLUSION

Tuberculous peritonitis may be fatal but is medically cured if diagnosed in a timely fashion. Although both non-invasive and invasive tests have additional benefits, clinician suspicion is still the first step for the diagnosis of tuberculous peritonitis.

Systematic review: tuberculous peritonitis--presenting features, diagnostic strategies and treatment

The peritoneum is one of the most common extrapulmonary sites of tuberculous infection. Peritoneal tuberculosis remains a significant problem in parts of the world where tuberculosis is prevalent. Increasing population migration, usage of more potent immunosuppressant therapy and the acquired immunodeficiency syndrome epidemic has contributed to a resurgence of this disease in regions where it had previously been largely controlled. Tuberculous peritonitis frequently complicates patients with underlying end-stage renal or liver disease that further adds to the diagnostic difficulty. The diagnosis of this disease, however, remains a challenge because of its insidious nature, the variability of its presentation and the limitations of available diagnostic tests. A high index of suspicion is needed whenever confronted with unexplained ascites, particularly in high-risk patients. Based on a systematic review of the literature, we recommend: tuberculous peritonitis should be considered in the differential diagnosis of all patients presenting with unexplained lymphocytic ascites and those with a serum-ascites albumin gradient (SAAG) of <11 g/L; culture growth of Mycobacterium of the ascitic fluid or peritoneal biopsy as the gold standard test; further studies to determine the role of polymerase chain reaction, ascitic adenosine deaminase and the BACTEC radiometric system for acceleration of mycobacterial identification as means of improving the diagnostic yield; increasing utilization of ultrasound and computerized tomographic scan for the diagnosis and as a guidance to obtain peritoneal biopsies; low threshold for diagnostic laparoscopy; treatment for 6 months with the first-line antituberculous drugs (isoniazid, rifampicin, ethambutol and pyrazinamide) in uncomplicated cases.

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.

Clinical and radiological deterioration in a patient with AIDS

Paradoxical clinical deterioration of miliary tuberculosis, characterized by pulmonary and abdominal manifestations, is reported in a patient with the acquired immunodeficiency syndrome, after initiation of treatment with highly active antiretroviral therapy. Paradoxical reaction was attributed to partial restoration of cell-mediated immunity related to highly effective antiretroviral therapy. Because tuberculosis has a high prevalence in HIV patients and tuberculosis is often characterized by miliary spreading of disease in these patients, it is important to recognize this phenomenon.

Colorectal tuberculosis

Our objective was to evaluate the incidence of colorectal tuberculosis in our series and to study its radiological spectrum. A total of 684 cases of proven gastrointestinal tuberculosis with positive barium contrast findings seen over a period of more than one decade were evaluated. The study did not include cases where colon was involved in direct contiguity with ileo-caecal tuberculosis. Seventy-four patients (10.8%) had colorectal tuberculosis. Commonest site involved was transverse colon, closely followed by rectum and ascending colon. Radiological findings observed were in the form of strictures (54%), colitis (39%) and polypoid lesions (7%). Complications noted were in the form of perforations and fistulae in 18.9% of cases. Colorectal tuberculosis is a very common site for gastrointestinal tuberculosis. Typical findings of colorectal tuberculosis are strictures, signs of colitis and polypoid lesions. Common complications are perforation and fistulae.

Gastrointestinal tuberculosis

Gastrointestinal tuberculosis is defined as infection of the peritoneum, hollow or solid abdominal organs, and abdominal lymphatics with Mycobacterium tuberculosis organisms. Gastrointestinal tuberculosis is relatively rare in the United States and is the sixth most common extrapulmonary location. Populations at risk include immigrants to the United States, the homeless, prisoners, residents of long-term care facilities, and the immunocompromised. The peritoneum and the ileocecal region are the most likely sites of infection and are involved in the majority of cases by hematogenous spread or through swallowing of infected sputum from primary pulmonary tuberculosis. Pulmonary tuberculosis is apparent in less than half of patients. Patients usually present with abdominal pain, weight loss, fever, anorexia, change in bowel habits, nausea, and vomiting. The diagnosis is often delayed and is usually made through a combination of radiologic, endoscopic, microbiologic, histologic, and molecular techniques. Antimicrobial treatment is the same as for pulmonary tuberculosis. Surgery is occasionally required.

A clinical dilemma: abdominal tuberculosis

AIM: To evaluate the clinical, radiological and microbiological properties of abdominal tuberculosis (TB) and to discuss methods needed to get the diagnosis.

METHODS: Thirty-one patients diagnosed as abdominal TB between March 1998 and December 2001 at the Gastroenterology Department of Kartal State Hospital, Istanbul, Turkey were evaluated prospectively. Complete physical examination, medical and family history, blood count erythrocyte sedimentation rate, routine biochemical tests, Mantoux skin test, chest X-ray and abdominal ultrasonography (USG) were performed in all cases, whereas microbiological examination of ascites, upper gastrointestinal endoscopy, colonoscopy or barium enema, abdominal tomography, mediastinoscopy, laparoscopy or laparotomy were done when needed.

RESULTS: The median age of patients (14 females, 17 males) was 34.2 years (range 15-65 years). The most frequent symptoms were abdominal pain and weight loss. Eleven patients had active pulmonary TB. The most common abdominal USG findings were ascites and hepatomegaly. Ascitic fluid analysis performed in 13 patients was found to be exudative and acid resistant bacilli were present in smear and cultured only in one patient with BacTec (3.2%). Upper gastrointestinal endoscopy yielded nonspecific findings in 16 patients. Colonoscopy performed in 20 patients showed ulcers in 9 (45%), nodules in 2 (10%) and, stricture, polypoid lesions, granulomatous findings in terminal ileum and rectal fistula each in one patient (5%). Laparoscopy on 4 patients showed dilated bowel loops, thickening in the mesentery, multiple ulcers and tubercles on the peritoneum. Patients with abdominal TB were divided into three groups according to the type of involvement. Fifteen patients (48%) had intestinal TB, 11 patients (35.2%) had tuberculous peritonitis and 5 (16.8%) tuberculous lymphadenitis. The diagnosis of abdominal TB was confirmed microbiologically in 5 (16%) and histo-pathologically in 19 patients (60.8%). The remaining nine patients (28.8%) had been diagnosed by a positive response to antituberculous treatment.

CONCLUSION: Neither clinical signs, laboratory, radiological and endoscopic methods nor bacteriological and histopathological findings provide a gold standard by themselves in the diagnosis of abdominal TB. However, an algorithm of these diagnostic methods leads to considerably higher precision in the diagnosis of this insidious disease which primarily necessitate a clinical awareness of this serious health problem.

CT features in abdominal tuberculosis: 20 years experience

BACKGROUND: Abdominal tuberculosis (TB) is endemic in the developing world and is reemerging in the West. Since computed tomography (CT) has the ability to demonstrate changes in the peritonium, mesentry, lymphnodes, bowel and solid organs and is being increasingly used for primary evaluation of abdominal conditions, it is important to be familiar with the CT features of the disease. METHODS: CT findings were retrospectively analysed in 49 patients with proved abdominal TB. Patients with genitourinary TB and with AIDS/HIV were not included in the study. RESULTS: Peritoneal involvement was the most common feature (77.5%) with ascites (wet peritonitis) seen in more than half the cases (55.2%). The rest showed peritoneal, mesenteric or omental thickening or mass formation but no ascites (dry peritonitis). Other findings included lymphadenopathy (46.9% mainly of diffuse nature, bowel wall thickening (38%) and solid organ involvement (20.4%). CONCLUSIONS: CT reliably demonstrates the entire range of findings which need interpretation in the light of clinical and laboratory data.

Mycobacterial infections: still a millennium bug--the imaging features of mycobacterial infections

Mycobacterial infection is re-emerging as a major health care concern. Although Mycobacterium tuberculosis(MTB) is still the most important pathogen, atypical mycobacterium (AMB) infections are becoming increasingly common. We present a pictorial review of the imaging features of these infections in the chest, abdomen, brain and musculoskeletal system. Imaging similarities and differences between the normal and the immunocompromised host will be highlighted.

Abdominal tuberculosis

Tuberculosis has staged a global comeback and forms a dangerous combination with AIDS. The abdomen is one of the common sites of extrapulmonary involvement. Patients with abdominal tuberculosis have a wide range and spectrum of symptoms and signs; the disease is therefore a great mimic. Diagnosis, mainly radiological and supported by endoscopy, is difficult to make and laparotomy is required in a large number of patient. Management involves judicious combination of antitubercular therapy and surgery which may be required to treat complications such as intestinal obstruction and perforation. The disease, though potentially curable, carries a significant morbidity and mortality.

Imaging of tuberculosis--experience from 503 patients. I. Tuberculosis of the chest

PURPOSE

To give an overview of 503 patients with tuberculosis (TB) and to describe the radiologic findings of chest TB.

MATERIAL AND METHODS

A total of 503 patients with proven TB were reviewed; 266 had chest involvement.

RESULTS

Lung lesions were demonstrated in 214 patients. Infiltrates in the basal parts of the lungs or pleural effusion were often primarily mistaken for viral or bacterial infections. Consolidations within the lungs and pleural thickening were sometimes indistinguishable from malignancy. Positive culture of the sputum without lung lesions was encountered in 12 cases. Enlarged mediastinal lymph nodes were demonstrated in 67 cases, 35 without lesions in the lungs. The lymphadenopathy could be extensive, and both clinically and radiologically indistinguishable from lymphoma.

CONCLUSION

Due to the present increase in incidence of TB and the fact that TB can mimic many other conditions, it is important that both clinicians and radiologists have TB high on the list for differential diagnoses.