Controversies in classification of peritoneal tuberculosis and a proposal for clinico-radiological classification

Clinical and Radiological Parameters to Discriminate Tuberculous Peritonitis and Peritoneal Carcinomatosis

It is challenging to differentiate between tuberculous peritonitis and peritoneal carcinomatosis due to their insidious nature and intersecting symptoms. Computed tomography (CT) is the modality of choice in evaluating diffuse peritoneal disease. We conducted an ambispective analysis of patients suspected as having tuberculous peritonitis or peritoneal tuberculosis between Jan 2020 to Dec 2021. The study aimed to identify the clinical and radiological features differentiating the two entities. We included 44 cases of tuberculous peritonitis and 45 cases of peritoneal carcinomatosis, with a median age of 31.5 (23.5-40) and 52 (46-61) years, respectively (p ≤ 0.001). Fever, past history of tuberculosis, and loss of weight were significantly associated with tuberculous peritonitis (p ≤ 0.001, p = 0.038 and p = 0.001). Pain in the abdomen and history of malignancy were significantly associated with peritoneal carcinomatosis (p = 0.038 and p ≤ 0.001). Ascites was the most common radiological finding. Loculated ascites, splenomegaly and conglomeration of lymph nodes predicted tuberculous peritonitis significantly (p ≤ 0.001, p = 0.010, p = 0.038). Focal liver lesion(s) and nodular omental involvement were significantly associated with peritoneal carcinomatosis (p = 0.011, p = 0.029). The use of clinical features in conjunction with radiological findings provide better diagnostic yields because of overlapping imaging findings.

Frequency, outcomes, and need for intervention in stricturing gastrointestinal tuberculosis: a systematic review and meta-analysis

BACKGROUND

Gastrointestinal strictures impact clinical presentation in abdominal tuberculosis and are associated with significant morbidity.

AIM

To conduct a systematic review of the prevalence of stricturing disease in abdominal and gastrointestinal tuberculosis and response to antitubercular therapy (ATT).

METHODS

We searched Pubmed and Embase on 13th January 2022, for papers reporting on the frequency and outcomes of stricturing gastrointestinal tuberculosis. The data were extracted, and pooled prevalence of stricturing disease was estimated in abdominal tuberculosis and gastrointestinal (intestinal) tuberculosis. The pooled clinical response and stricture resolution (endoscopic or radiologic) rates were also estimated. Publication bias was assessed using the Funnel plot and Egger test. The risk of bias assessment was done using a modified Newcastle Ottawa Scale.

RESULTS

Thirty-three studies reporting about 1969 patients were included. The pooled prevalence of intestinal strictures in abdominal tuberculosis and gastrointestinal TB was 0.12 (95%CI 0.07-0.20, I² = 89%) and 0.27 (95% CI 0.21-0.33, I² = 85%), respectively. The pooled clinical response of stricturing gastrointestinal tuberculosis to antitubercular therapy was 0.77 (95%CI 0.65-0.86, I² = 74%). The pooled stricture response rate (endoscopic or radiological) was 0.66 (95%CI 0.40-0.85, I² = 91%). The pooled rate of need for surgical intervention was 0.21 (95%CI 0.13-0.32, I² = 70%), while endoscopic dilatation was 0.14 (95%CI 0.09-0.21, I² = 0%).

CONCLUSION

Stricturing gastrointestinal tuberculosis occurs in around a quarter of patients with gastrointestinal tuberculosis, and around two-thirds of patients have a clinical response with antitubercular therapy. A subset of patients may need endoscopic or surgical intervention. The estimates for the pooled prevalence of stricturing disease and response to ATT had significant heterogeneity.

Abdominal Tuberculosis Presenting as an Umbilical Sinus: A Case Report

Abdominal tuberculosis, a form of extrapulmonary tuberculosis is common in developing countries like India. Manifestations of abdominal tuberculosis are widely variable. Its incidence is high among human immunodeficiency virus (HIV) infected patients in the adult population. Here, we report a 26-year-old male, initially treated in a private clinic for abdominal distention, loss of appetite, and loss of weight for one month. Magnetic resonance imaging (MRI) of the abdomen showed a large loculated fluid collection. Computed tomography (CT) of the chest showed signs of pulmonary tuberculosis. The patient was started on anti-tuberculosis therapy (ATT) and discharged. Ten days later, the patient presented to our hospital with foul-smelling pus discharging from the umbilicus and necrosis of the surrounding tissue. Abdominal examination revealed a tense, distended, and tender abdomen. The patient was referred for emergency laparotomy. The intraoperative findings showed features that were a combination of plastic fibrous type and encysted loculated type of peritoneal tuberculosis. The above-mentioned case describes a very uncommon presentation of abdominal tuberculosis. A high degree of suspicion is required for diagnosing such conditions, especially in immunocompromised individuals. The case report also highlights the difficulties in the diagnosis of abdominal tuberculosis.

ASCITIC AND SERUM LEVELS OF TUMOR BIOMARKERS (CA 72-4, CA 19-9, CEA AND CA 125) IN DISCRIMINATION OF CAUSE OF ASCITES: A PROSPECTIVE STUDY

BACKGROUND

The role of ascitic and serum levels of various tumour biomarkers in the discrimination of cause of ascites is not well established.

OBJECTIVE

To evaluate the role of serum and ascitic levels of tumor biomarkers (CA 72-4, CA 19-9, CEA and CA 125) in discrimination of cause of ascites.

METHODS

A prospective study was conducted in consecutive patients presenting with ascites. Serum and ascitic levels of CA 19-9, CA 125, CA 72-4 and carcinoembryonic antigen (CEA) were determined at the presentation. The patients with cirrhotic ascites, tuberculous peritonitis (TBP) and peritoneal carcinomatosis (PC) were eventually included in analysis.

RESULTS

Of the 93 patients (58 males, mean age 47 years) included, the underlying cause was cirrhosis in 31, PC in 42 and peritoneal tuberculosis in 20. The best cutoff for discriminating benign and malignant ascites for serum CEA, CA 19-9 and CA 72-4 were 6.7 ng/mL, 108 IU/mL and 8.9 IU/mL, respectively. The best cutoff for discriminating benign and malignant ascites for ascitic CA 125, CEA, CA 19-9 and CA 72-4 were 623 IU/mL, 8.7 ng/mL, 33.2 IU/mL and 7 IU/mL, respectively.

CONCLUSION

The performance of single biomarker for the prediction of underlying PC is low but a combination of serum CA 19-9 and CA 72-4 best predicted the presence of peritoneal carcinomatosis.

Clinical, laboratory and evolutionary features of abdominal tuberculosis in comparison with other forms of extrapulmonary tuberculosis

BACKGROUND/OBJECTIVES

Tuberculosis is a multisystem disease that might affect any organ. Abdominal tuberculosis (ABT) represents 5-17% from all extrapulmonary tuberculosis (EPT) sites. We aimed to study the clinical, laboratory and evolutionary features of ABT cases and to identify predictive factors associated with ABT.

METHODS

We conducted a retrospective study including all patients hospitalized in the infectious diseases department for EPT between 1991 and 2019. We studied the characteristics of ABT cases, and we compared them with other EPT cases.

RESULTS

We identified 519 patients with EPT, among whom 86 (16.6%) patients had ABT. There were 58 females (67.4%). Peritoneal tuberculosis was the most common clinical form of ABT (68.6%), followed by intestinal tuberculosis (18.6%). Patients aged 60 years and above were significantly less affected with ABT (odds ratio (OR) = 0.2; p = 0.001). The revealing systemic symptoms including fever (OR = 2.04; p = 0.006), weight loss (OR = 2.5; p < 0.001) and anorexia (OR = 1.7; p = 0.021) were significantly more frequent among ABT patients. Inflammatory markers including C-reactive protein levels (37 [10-89] mg/l vs 10 [4-57] mg/l; p < 0.001) and erythrocyte sedimentation rates (43 [15-95] mm/h vs 27 [15-60] mm/h; p = 0.044) were significantly higher among ABT cases. Multivariate logistic regression analysis showed that anorexia (adjusted OR (AOR) = 1.9; p = 0.015) and pulmonary involvement (AOR = 3.3; p = 0.002) were independent predictors of higher rate of ABT. Concomitant involvement of neuro-meningeal (AOR = 0.18; p = 0.001) and osteo-articular (AOR = 0.2; p = 0.01) sites, 40-59 (AOR = 0.2; p < 0.001) and ≥60 (AOR = 0.2; p < 0.001) age groups as well as hemoglobin rate (AOR = 0.7; p < 0.001) were independently associated with lower rate of ABT.

CONCLUSIONS

Anorexia and pulmonary involvement were independent predictors of higher rate of ABT. Concomitant involvement of neuro-meningeal and osteo-articular sites, 40-59 and ≥60 age groups and hemoglobin rate were independently associated with lower rate of ABT.

Recent updates in diagnosis of abdominal tuberculosis with emphasis on nucleic acid amplification tests

INTRODUCTION

Abdominal tuberculosis (TB) is a common epitome of extrapulmonary TB (EPTB), wherein peritoneal and intestinal TB are the most prevalent forms. Diagnosis of abdominal TB is a daunting challenge owing to variable anatomical locations, paucibacillary nature of specimens and atypical clinical presentations that mimic other abdominal diseases, such as Crohn's disease and malignancies. In this review, we made a comprehensive study on the diagnosis of abdominal TB.

AREA COVERED

Various modalities employed for abdominal TB diagnosis include clinical features, imaging, bacteriological tests (smear/culture), histopathological/cytological observations, interferon-gamma release assays and nucleic acid amplification tests (NAATs). Among NAATs, loop-mediated isothermal amplification assay, PCR, multiplex-PCR, nested PCR, real-time PCR and GeneXpert® MTB/RIF were discussed. Identification of circulating Mycobacterium tuberculosis cell-free DNA by real-time PCR within ascitic fluids is another useful approach.

EXPERT OPINION

Several novel molecular/immunological methods, such as GeneXpert Ultra, aptamer-linked immobilized sorbent assay, immuno-PCR (I-PCR) and nanoparticle-based I-PCR have recently been developed for detecting pulmonary TB and several EPTB types, which may also be explored for abdominal TB diagnosis. Precise and prompt diagnosis of abdominal TB may initiate an early therapy so as to reduce the complications, i.e. abdominal pain, ascites, abdominal distension, intestinal obstruction/perforation, etc., and avoid surgical involvement.Plain Language SummaryAbdominal tuberculosis (TB) is a manifestation of extrapulmonary TB (EPTB), where peritoneal and intestinal TB are two major forms. Diagnosis of abdominal TB is difficult owing to low bacterial load present in clinical samples and non-specific clinical presentations as it mimics other diseases such as inflammatory bowel diseases, abdominal malignancies, etc. Bacteriological tests (smear/culture) almost fail owing to poor sensitivities and it is not always possible to get representative tissue samples for histopathological and cytological observations. In recent years, molecular tests i.e. nucleic acid amplification tests (NAATs), such as PCR/multiplex-PCR (M-PCR), nested PCR and GeneXpert are widely employed. Markedly, PCR/M-PCR and nested PCR exhibited reasonable good sensitivities/specificities, while GeneXpert revealed low sensitivity in most of the studies but high specificity, thus it could assist in differential diagnosis of intestinal TB and Crohn's disease. Further, novel molecular/immunological tests employed for pulmonary TB and other EPTB types were described and those tests can also be utilized to diagnose abdominal TB. Reliable and rapid diagnosis of abdominal TB would initiate an early start of anti-tubercular therapy and reduce the severe complications.

Angioplasty With Stent Implantation for Portal Venous Stenosis Caused by Abdominal Tuberculosis: A Case Report and Literature Review

Abdominal tuberculosis is one of common forms of extra-pulmonary tuberculosis. However, portal vein involvement leading to portal venous stenosis and portal hypertension is a rare complication in abdominal tuberculosis. Because of the non-specific presentations and insensitive response to anti-tuberculosis therapy of the lesions involving portal vein, it continues to be both a diagnostic and treatment challenge. We have reported a 22-year-old woman presented with massive ascites and pleural effusion, which was proved to be TB infection by pleural biopsy. After standard anti-tuberculosis therapy, her systemic symptoms completely resolved while ascites worsened with serum-ascites albumin gradient >11 g/L. Contrast-enhanced computed tomography and portal venography showed severe main portal vein stenosis from compression by multiple calcified hilar lymph nodes. Finally, the patient was diagnosed with portal venous stenosis due to lymphadenopathy after abdominal tuberculosis infection. Portal venous angioplasty by balloon dilation with stent implantation was performed and continued anti-tuberculosis therapy were administrated after discharge. The ascites resolved promptly with no recurrence occurred during the six-month follow-up. Refractory ascites due to portal venous stenosis is an uncommon vascular complication of abdominal tuberculosis. Portal venous angioplasty with stent placement could be a safe and effective treatment for irreversible vascular lesions after anti-tuberculosis therapy.

Locally advanced gallbladder cancer: a review of the criteria and role of imaging

Gallbladder carcinoma (GBC) is among one of the gastrointestinal malignancies with extremely dismal prognosis. This is due to the advanced stage at presentation. Majority of the patients with GBC are not considered candidates for surgery because of the locally advanced disease or metastases. However, with the accumulating evidence regarding the role of neoadjuvant chemotherapy, there is a need to correctly identify a subset of patients with locally advanced GBC who will benefit maximally from neoadjuvant chemotherapy and will be successfully downstaged to receive curative (R0) surgery. In this context, there is a lack of consensus and different groups have resorted to criteria for locally advanced disease eligible for neoadjuvant chemotherapy based on personal or institutional experiences. Imaging plays a critical role in the evaluation of patients with GBC as it helps stratify patients into resectable and unresectable. Imaging also has the potential to identify patients with locally advanced GBC and hence facilitate neoadjuvant chemotherapy and improve outcomes. In this review, we evaluate the various criteria for locally advanced GBC and the role of imaging in this scenario.

Diagnostic accuracy of the Xpert MTB/RIF assay for abdominal tuberculosis: a systematic review and meta-analysis

BACKGROUND

We performed a meta-analysis to determine diagnostic accuracy of Xpert MTB/RIF for diagnosis of abdominal (intestinal or peritoneal) tuberculosis (TB) in various tissues (intestinal, omental/peritoneal tissue or ascitic fluid).

METHODS

Electronic databases were searched for observational studies on use of Xpert MTB/RIF in ascitic fluid, peritoneal, or omental tissue for diagnosis of peritoneal and intestinal TB. We calculated the pooled sensitivity, specificity and diagnostic odds ratio of Xpert MTB/RIF for diagnosis of peritoneal TB in comparison to composite reference standard (CRS) and culture, and in comparison to CRS for intestinal TB.

RESULTS

Twenty-five observational studies were included. The pooled sensitivity and specificity as assessed with peritoneal culture from ascites as an Index test was 64% (95% Confidence Interval [C.I.] 49-76%) and 97% (95% C.I., 95-99%) respectively and with peritoneal CRS was 30% (95% C.I., 22-40%) and 100% (95% C.I., 98-100%) respectively. In the intestinal group, the pooled sensitivity and specificity of Xpert MTB/RIF was 23% (95% C.I., 16-32%) and 100% (95% C.I., 52-100%). The AUC of peritoneal culture and intestinal tissue was 0.935 and 0.499.

CONCLUSION

Xpert MTB/RIF has modest sensitivity for diagnosis of peritoneal and intestinal tuberculosis but has a good specificity.

PROSPERO REGISTRATION

CRD42020140545.

Diagnostic performance of CT for differentiating peritoneal tuberculosis from peritoneal carcinomatosis: a systematic review and meta-analysis

AIM

To undertake a systematic review and meta-analysis of the diagnostic performance of CT for differentiating peritoneal tuberculosis (PTB) from peritoneal carcinomatosis (PC).

MATERIAL AND METHODS

PubMed, Embase, the Web of Science, and the Cochrane Library were searched for papers published before 23 July 2019. The methodological quality of the studies was analysed. Overlapping descriptors used in different studies to denote the same image finding were subsumed under a single CT feature. Sensitivity, specificity, and positive and negative likelihood ratios were pooled. A summary receiver operating characteristic curve (sROC) was constructed and the area under the curve (AUC) of the included studies was calculated when possible.

RESULTS

Six studies were included and 17 CT features were analysed. The pooled sensitivity and specificity of smooth peritoneal thickening were 59% (95% CI: 52-66%) and 84% (95% CI: 79-88%), respectively. The AUC of smooth peritoneal thickening was 0.83. Omentum line/rim, lymph node necrosis or calcification, and mesenteric macro nodules had a pooled specificity ranging from 95% to 100% and a pooled sensitivity ranging from 12% to 67%. The other 12 signs had a pooled sensitivity ranging from 21% to 79% and a pooled specificity ranging from 19% to 81%. Omentum involvement (cake-like pattern) showed a threshold-effect, so only the AUC (=0.70) was calculated.

CONCLUSIONS

Smooth peritoneal thickening shows fairly good diagnostic accuracy, while omentum rim/line, lymph nodes necrosis or calcification, mesenteric macro nodules have good specificity but limited sensitivity. The informative features summarised in this study may aid clinical practice and future studies.